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Wednesday, 11 February 2015


Swine management could be described as the sum total of what the farmer do not do which affect the profitability of swine operation.
Even the poorest swine operation could be made successful with good management. Conversely, the very best swine operation could become unprofitable with poor management. It is for this reason that management has been said to be the key to profitable swine operation. The management which is contributed to a swine operation is a key factor in the success of the Feeding Program.
Knowledge of feeding swine is important from an economic standpoint because feeds account for approximately 65-75% of the total cost of producing pork. For this reason every swine producer would endeavour to provide a ration that is both satisfactory and inexpensive.
Therefore, since the modern swine producer is interested in maximum performance, a good feeding program and excellent management is of great importance.
The information contained in this publication does not cover all the details involved in pig rearing. The intention is to provide certain guides towards proper and profitable pig husbandry.
One of, the first considerations in pig farming is System Planning. The first principle of planning is to consider the whole operation.
As you plan, keep in mind the expansion 5-15 years ahead or longer.  Consider the flow patterns of three major products -feed, pigs and wash, and handle each with a minimum of labour and expense; bearing in mind that the system must provide optimal environmental considerations for efficient pig growth, and operation comfort.

Breed of Swine

All breeds of swine originated from two genera:-
(a) European wild boar           Sus scrofa
(b) East Indian pig                  Sus vitatus /domesticus

Zoological classification and comparison of certain domestic species. (Plimpton, R. F., and J. F Stephens, Animals and Science for Man: A Study Guide, 2nd edition, Burgess Publishing Company, 1979)

Some pigs perform better than others, even with the same feeding and management; they will produce more off-spring, grow faster, produce less fat and have less health problems.  Feeding and management has the most direct influence on production and the success of the business, but the kind of breeding stock you have can limit what good feeding and management can do.
Pigs like other animals inherit bad or good characteristics from their parents and ancestors.  In herds where stock has been carefully selected for good traits (eg) over several generations there is a greater chance of finding gilts or a boar that are better than average.
Good breeding stocks with superior traits are essential to the pig industry.  The major breeds of swine are classified into two groups – Bacon type and Meat type.

Bacon Type                                                     Meat type
Yorkshire/ Large White                                  Hampshire
Landrace                                                          Duroc
Lacombe                                                          Spotted Poland China
                                                                        Chester White
The breeds commonly found in Jamaica are Duroc, Hampshire, landrace, large white.
Large white and Land-race are more likely than other breeds to have excellent productive traits such as litter size, milking ability and conception rate, but unless careful selection is practiced t o prevent weak feet and legs, and lower quality of pork cuts.
Duroc and Hampshire are more likely than other breeds to have a high rate of gain, strong feet and legs. Lean, low fat pork cuts but poor productive traits.
A brief description of the more successful breeds in the industry in Jamaica is as follows:

1.         Large White/Yorkshire
The Large White or Yorkshire is one of the older English breeds which was introduced locally many years ago. It is white in colour (occasionally one or two black spots) and therefore like all other white breeds is susceptible to sun scald. Other identifying features are its erect ears, and long face. It is of medium body length and the flashing is quite firm. It is reputed to have good mothering ability although individuals have been observed locally to develop a lack of milk at farrowing. It is generally accepted as a good breed for crossing in a market hog operation.

2.         Landrace
This is another breed which is white in colour but can be distinguished from other breeds by its extremely long length (it has more ribs than other breeds), its flopped ears and deep sides. The pig originated in Denmark for bacon production several years ago. It has been used in several parts of the world for cross - breeding to take advantage of those feature already mentioned. The land-race has less fat on average than other breeds -a feature which can be usefully incorporated in a programme to produce hogs for meat production.

                        3.         Hampshire
   This breed has a more recent history than either of the two, breeds mentioned earlier and was developed in the U.S. especially for the meat market. It is readily distinguished from other breeds being black in colour with a characteristic white band which encircles the body at the shoulder region. Sometimes this white belt includes the front feet. The ham are more rounded and filled than other breeds, the flesh is very firm and the proportion of
meat to fat is extremely high -a feature which the males are capable of passing to their offspring very faithfully. Again, individuals of this breed make excellent crosses for market-hog operations.

4.         Duroc           
 Individuals of this breed are readily identified by their red colour. The breed is most widely known for the ability to put on weight rapidly (good growth rate). The face is short with short ears which flop over the eyes. Because of the rapid rate of gain, many farmers utilize the breed in crossing with other breeds. Others prefer to maintain them in pure strain. .
Other Breeds
There are several newer breeds which have been developed to take advantages of "hybrid vigour", that is the beneficial effect of crossing inbred lines. However before the farmer attempts to utilize any of these new breeds, he should first obtain information on the particular breed in which he has an interest.

Production Systems

Factors favouring Swine Production
1. Swine excel all other animals except broilers in feed conversion. 3.50: 1 vs. 2.50: 1
2. Swine are prolific. Sows produce up to 12 pigs per litter.
3. Swine excel in dressing percentage 65-80% of live weight, Broilers 80-90% cow 50-60%.
     sheep 55-65%
4. Pork is nutritious. (A 3-oz serving of cooked, lean pork will supply the following nutrients in a 2,200 calorie diet. Protein 50 %, phosphorus 25 %, Fe 6 %, Zn 20 % , Riboflavin 22 %, Thiamine 67 %, B12 32 %, Niacin 30 %, Calories 8 %, F 11 %.) (Damron pp460)
5. Pigs are efficient converters of waste and by-product into pork.
6. Since swine are well adapted to the practice of self-feeders, labour is kept to a minimum.
7. Swine require a small investment for buildings and equipment.
8. The pig is adapted to both diversified and intensified agriculture.
9. The initial investment in getting into the business is small and the returns come quickly.
10. The spread in price in market hog is .relatively small.
11. Pigs are unexcelled as a source of farm meat.
12. The pig excels all other farm animals in fat storing ability.
Factors unfavourable to swine production
  1. Because of the nature of their diet and their rapid growth rates, pigs are extremely sensitive to unfavourable rations and to careless management.
  2. Because of the nature of the digestive tract a pig must be fed a maximum of concentrates and a minimum of roughage.
  3. Swine are susceptible to numerous diseases and parasites.
  4. Fence of a more expensive kind are necessary in pig raising.
  5. Sows need skilled attention at farrowing time.
  6. Because of their ‘rooting’ and close grazing habits, pigs are hard on pastures.

 Production Systems
There are several alternatives available to a farmer who wishes to enter pig production. Some of which are:
1. Production of Breeding Stock
2. Production of Weaners (feeder pigs)
3. Production of Fatteners or feeder pigs
4. Farrow to finish operation.
5. Integrated Corporate Production

Production for Breeding Stock
This is a highly specialized system that is geared to produce genetically superior breeding stock. (Purebred or controlled crossbred primary products are breeding boars & gilts or show pigs) Success of this type of enterprise is largely dependent on the ability of the operator, to apply the latest selection and breeding techniques that would result in herd improvement.

Production of Weaners
This is a production system where weaned pigs are generally sold at 8 to 12 weeks of age, when they weigh 35- 50 lbs. this type of enterprise is recommended for the farmer who:
  1. Can provide dry, warm facilities for farrowing.
  2. Has adequate and competent labour who can handle the important detetai1s of breeding, farrowing and record keeping.
  3. Is sanitation minded, 1ikes to work with and properly care for sows and nursing pigs.
  4. Has limited feed available.
  5. Realizes this type of enterprise can be profitable but only if top quality pigs are produced consistently, and at a high level of production per sow.

Production of Fatteners (Feeder pigs finishing)  
This involves feeding weaners to market weight (220-260lb). The source of weaners is very important because the health and performance of the pigs will largely determine the profitability of this type of enterprise. This type of system lends itself to automation and is recommended for the farmer who:-
1. Likes to feed and manage pigs of this size and age.
2. Has sufficient feed available to feed pigs through to market.
3. Has a good knowledge of nutritional requirements and good feeding practices.

Farrow to Finish Operation
This involves keeping a herd of sows and feeding the offspring to market weight. This type of operation is very desirable because control over diseases and carcass quality can be more rewarding and set backs in growth due to moving pigs from farm-to farm are minimized. However a combination of the skills required for the previous two systems' is necessary to maximize profits.

Integrated Corporate Production: This is the only growing (expanding) segment of the swine industry. Integrated operations can generally be described as farrow to finish and most often have their own seed stock production as well. The different phases of the operation are usually located on different sites. For instance several brood sows may be found in close proximity to each other, but far enough apart that biosecurity measures between the facilities are easily handled. Nursery facilities for just weaned pigs are commonly found on the same site or at a site close by. However, when the pigs are ready for finishing for market, they are taken to another site, which may be company owned facility or a contractor. (Damron pp440)


Select gilts to be retained for the breeding herd at five to six months of age or when they weigh 200 lb or more. Separate from the market herd and grow them out on 4 to 6 lb of a balanced 14% to 15% protein ration.


Gilts selected for herd replacements should meet the following criteria:

(1) Select gilts that do not have any hereditary defects or from lines that do not have a history of hereditary defects.

(2) Twelve or more prominent teats and from sow lines that are noted milkers.

(3) From lines and or families with high fertility rate noted for large litters and early sexual maturity.

(4) Large frame, structurally correct individuals, with quality bone and proper set to feet and legs.

(5) Healthy individuals from healthy good sows.

(6) Gilts should indicate a rapid rate of gain and have good feed efficiency.

(7) Lean with ample muscling.

(8) Where possible, utilize litter mate and sire records.
Gilts should be fed a balanced ration such that they will meet their genetic potential at breeding time and weigh approximately 220 to 280 lb without being overly fat (6 to 8 months of age).
Breed gilts during their second or third heat period (6 to 8 months). They should be bred on first day heat is observed and rebred 12 to 24 hours later if possible.
(1) In a commercial herd, double mating (best to use two different boars) may be employed. Research indicates an increase in litter size by approximately 1 to 1 1/2 pigs per litter by following the practice of breeding a second time 12-24 hours after the first service.
(2) In a purebred herd, use the same sire for the second breeding.
(3) Sows can be bred in the post weaning heat if pigs are weaned at 3 weeks of age or older and the sow is not in too thin a condition.
(4) Boars should be approximately seven to eight months old before being used in a breeding herd. The boar is considered to be mature (senior) at 15 months of age or older. The suggested maximum number of services / boar are listed in Table 1.
(5) It is recommended that boars be kept in thin, thrifty condition so that they are able to breed gilts and sows. The weight of boars is controlled by the amount of feed fed. In some cases this may vary from 2 to 6 lb per day.

Traits                           Standards
Litter size                    10 or more farrowed 8 or more weaned
Underline                    12 or more fully developed, well-spaced teats
Feet & legs                  wide stance front & rear; free in movement; good cushion to both front & rear legs; equal size toes.
Age at 230 lbs             155 days or less

Feed /gain, boar basis  240 lb of feed /100 lb of gain or less (60-230 lbs)
Daily gain (60-230 lb)             2.0lb / day or more
Back fat ultrasound                0.8 in or less (adjusted to 230 lb)

 1. Snout            5. Cheek          10. Fore leg                  15. Loin            20. Rump
2. Face              6. Jowl             11. Dew claw                 16. Side            21. Ham
3. Eye                7. Poll              12. Pastern                   17. Belly           22. Rear leg
4. Ear                8. Neck            13. Toes                       18. Fore flank     23. Tail
9. Shoulder       14. Back           19. Rear flank


There is no one best system of breeding or secret of success for any and all conditions. Each breeding program is an individual case. The choice of the system of breeding should be determined primarily by the size and quality of the herd, equipment available, finances and skill of the producer and by his ultimate goal.
Purebreeding - A purebred animal is defined as a member of breed which possesses a common ancestry and distinctive characteristics and is either registered or eligible for registration in that breed. Purebreeding is the mating of two purebred animals of the same breed. The purebred producer has the responsibility of producing genetically superior animals for the commercial producer.
Inbreeding - Inbreeding is the system of breeding in which closely related animals are mated. This includes (1) sire to daughter (2) son to dam and (3) brother to sister. Inbreeding is suggested for only highly qualified operators who are making an effort to stabilize important traits in a given set of animals. Intensive selection is needed to reduce the risk of producing undesirable traits in breeding stock when inbreeding is practiced.
Linebreeding - Linebreeding is a mild form of inbreeding in which the degree of relationship is less intense than in intensive inbreeding and is usually directed towards keeping the offspring related to some highly prized ancestor. The degree of relationship is not closer than half-brother half-sister matings or cousin matings, etc. Line breeding is practiced to conserve desirable traits of an outstanding boar or sow line.
Outbreeding- This is the opposite of inbreeding include crossbreeding, species cross, Grading up and outcrossing (more common form) (Cunningham, Taylor and Field)
Outcrossing - Outcrossing is the mating of unrelated animals (4-6 generations Cunningham pp385) of the same breed. The gene pairs are primary heterozygous, although there is a slight increase in homozygosity over time. Homozygosity for several breeds has been estimated at between 10 & 20 %.   .
Crossbreeding - Crossbreeding is the mating of two animals which are members of different breeds. There are two primary reasons for practicing crossbreeding (1) Breed complementation (Crossing breeding so their strength and weaknesses complement one another. There is no one breed that is superior in all desired production characteristics there planned crossbreeding programs that used breed complementation can significantly increased herd productivity)  (2) heterosis (hybrid vigor) (This is the increased in productivity in the crossed bred progeny above the average of the breed or lines that are crossed (parents). This system is being practiced by the majority of commercial swine producers because of the resulting hybrid vigor which makes possible improved production efficiency. Swine producers can use Duroc boar to increase prolificacy, a landrace boar to increase length or a spotted boar to increase muscling. Other breeds might also used to provide these traits. (Cunningham p 389) NB; Crossbreeding improves many of the traits that have low heritability. Table 2 lists the expected advantages of Crossbreds over Purebreds.
Species cross – Crossing of animals of different species example mule resulted from crossing the Jack of the ass species and the mare of the horse species (Equus assinus* Equus caballus). The hinny is the reciprocal cross of the mule. Goats and sheep have been crossed even though they have different genus (Capra, Ovis) classification. Fertilization occurs but embryos dies in early gestation.
Grading Up:   This refers to the continuous use of purebred sires of the same breed in a grade herd or flock. In this situation, grading up is similar to out crossing. The accumulated percentage of inheritance of the desired purebred is 50% (half), 75 % (three-fourth) 84.5 % (seven eight) and 94 % (fifteen sixteen) for four generations. The fourth generation resembles the purebred sires so closely in genetic composition that it approximates the purebred level.
Crisscrossing or two breed rotation - Boars of two different breeds are used in alternate generations. Crossbred sows resulting from this mating are bred back to the breed of the grandsire on the dam side. An example would be cross a Hampshire x Yorkshire sow, Yorkshire boar x crossbred Hampshire x York sow, Hampshire boar x crossbred Yorkshire x Hampshire sows, etc.
Another system of crisscrossing that might be followed would be Hampshire boar x Yorkshire sows - breed 1/2 Hamp 1/2 York sows to another Hamp boar producing 3/4 Hamp gilts which are crossed back to York boars. Boar rotation in this system - 2 Hamps 1 York.
Three breed rotation or triple crossing - This system involves the use of boars of several breeds attempting to capitalize on the strong traits within each breed. An illustration: Hampshire x Yorkshire producing crossbred Hampshire x York gilts crossed with a Duroc boar. The three way cross gilt in turn would be crossed back to a Yorkshire boar and then repeat the system. The attempt here is to capitalize on the muscling traits of the Hampshire, mothering ability of the York and the growth ability of the Duroc or any such combination of breeds which suits the producer's need.


Hand or individual mating of boars, sows and gilts is recommended over field mating where feasible. If pasture mating is practiced, it is recommended that the following be done:

(1) Divide the sow or gilt herd so as to have one boar per group.

(2) Alternate boars in the sow or gilt herd. Use one boar or set of boars one day and another boar or set of boars the next day.

(3) Boars of the same size and age can be run together during the off season. Boars of different ages should not be run together. Holding lots for boars should be constructed out of strong material that will restrain the animal adequately. Build pens narrow and long. To encourage exercise, feed at one end and water at the other. Furnish adequate shade and shelter for inclement weather.

(4) It is recommended that gilts and sows be kept separate during the gestation period.

(5) Sows and gilts may be either hand-fed or allowed access to a self-feeder every third day during the gestation period. Feeding can be controlled by:

(1) Feeding commercial cubes or shelled corn and supplement scattered out over the pasture to prevent boss sows from getting more than their share,
(2) Furnishing individual feeding stalls for greater control, or
(3) By practicing every third day feeding.
When every third day feeding is practiced, one feeder hole per sow should be allowed. Give them access to feed for 2 to 6 hours (depending on sow condition) in every 72 hour period.
Gilts should be acclimated to every third day feeding by starting every other day for a period of ten days and then moving to a third day basis. Gilts should be allowed 2 to 6 hours on a self-feeder out of each 72 hour period. Depending on condition, allow one feeder hole per animal with round type feeders being the most desirable.
The use of individual feeding stalls offers the best opportunity for:
(a) Feeding each sow or gilt to meet their needs.
(b) Elimination of "boss sow" effects.
(c) Reduction in feed wastage.
(d) Close observation of individual animals.

Table 3. Swine Gestation Table (115 Days).


Table1. Maximum Number of Services Per Boar

Hand Mating
Pen Mating
Per Month

Per Day
Per Week
Per Month
Mature Boar

Junior Boar

Table 2. Expected Advantage of Crossbreds Over Purebreds

First Cross
Multiple Cross

Litter size at farrowing

Litter size at weaning

Weight of ind. pigs at 154 days
Total litter wt. at 154 days

N.C.S.U. Experiment Station Bulletin 432, May 1967
Table:3. Swine Gestation Table (115 Days), If Bred Jan. 1 - April 30
If Bred
Will Farrow
If Bred
Will Farrow
If Bred
Will Farrow
If Bred
Will Farrow
Jan 1
Apr 26
Feb 1
May 27
Mar 1
Jun 24
Apr 1
Jul 25
Jan 2
Apr 27
Feb 2
May 28
Mar 2
Jun 25
Apr 2
Jul 26
Jan 3
Apr 28
Feb 3
May 29
Mar 3
Jun 26
Apr 3
Jul 27
Jan 4
Apr 29
Feb 4
May 30
Mar 4
Jun 27
Apr 4
Jul 28
Jan 5
Apr 30
Feb 5
May 31
Mar 5
Jun 28
Apr 5
Jul 29
Jan 6
May 1
Feb 6
Jun 1
Mar 6
Jun 29
Apr 6
Jul 30
Jan 7
May 2
Feb 7
Jun 2
Mar 7
Jun 30
Apr 7
Jul 31
Jan 8
May 3
Feb 8
Jun 3
Mar 8
Jul 1
Apr 8
Aug 1
Jan 9
May 4
Feb 9
Jun 4
Mar 9
Jul 2
Apr 9
Aug 2
Jan 10
May 5
Feb 10
Jun 5
Mar 10
Jul 3
Apr 10
Aug 3

Jan 11
May 6
Feb 11
Jun 6
Mar 11
Jul 4
Apr 11
Aug 4
Jan 12
May 7
Feb 12
Jun 7
Mar 12
Jul 5
Apr 12
Aug 5
Jan 13
May 8
Feb 13
Jun 8
Mar 13
Jul 6
Apr 13
Aug 6
Jan 14
May 9
Feb 14
Jun 9
Mar 14
Jul 7
Apr 14
Aug 7
Jan 15
May 10
Feb 15
Jun 10
Mar 15
Jul 8
Apr 15
Aug 8
Jan 16
May 11
Feb 16
Jun 11
Mar 16
Jul 9
Apr 16
Aug 9
Jan 17
May 12
Feb 17
Jun 12
Mar 17
Jul 10
Apr 17
Aug 10
Jan 18
May 13
Feb 18
Jun 13
Mar 18
Jul 11
Apr 18
Aug 11
Jan 19
May 14
Feb 19
Jun 14
Mar 19
Jul 12
Apr 19
Aug 12

Selection Criteria contd
  1. Improve growth and efficiency by selecting gilts and boars with fast rates of growth.
  2. Improve carcass grades by selecting gilts and boars with low back fat thickness.
  3. Replace 30 to 40% of the female herd per year. This means that the female herd will turn over every 2 to 2 1/2 years.
(a) Failure to conceive after 3 mating or 7 weeks in the breeding pen.
(b) The development of unsoundness or disease problems that indicate they cannot survive.
(c) Two consecutive litters in which litter size is below average.
(d) Age -cull all sows after 8 litters if litter number is below average.
  1. Purchase outside stock from herds with a high healthy status.
  2. Keep records on key f actors
  3. Use records in making selection decision, animals should be ranked and selected on the basis of net merit in performance unless a visual appraisal shows unsoundness that will dearly handicap reproductive performance or limit reproductive life. A pig should also show evidence of good health and should be docile in temperament.

Commercial Breeding Program
To build a profitable herd it is good to aim at weaning 10 pig/litter/sow, 2.25 litters/sow/year, 160/170 days market (boar/gilt). Efficient housing, high health standards, balanced ration, and sound breeding will result in excellence in reproduction, growth efficiency and good carcass grades.
The most suitable system to adopt is a system of cross breeding and selection.

 Production of Seed Stock  
 Seed stock refers to stock that will be used for breeding. The seed stock producer aims for a higher level of merit in the herd so that a commercial producer who buys stock from him is assured of getting quality animals which he will eventually use to make crosses f or market hog production.
The seed stock producer accomplishes this high merit with the aim of testing and selection based on record of performance. He maintains accurate records on all his stock.
From time to time it becomes necessary to purchase from outside herds to avoid a too high proportion of inbreeding. However, in the purchase from outside herds he does so only on the basis of the records of such a herd and of course, after he is satisfied that the breed is pure.

Breeding Systems for Commercial Production
The best breeding system for commercial production differ from those suited to seed stock production. As previously mentioned mating of unrelated individuals results in more vigour and greater thrift in the off-spring than the mating of related individuals. While there are many modifications available to commercial producer for running operations these modifications are all based on out- breeding and cross-breeding.
Generally, two or three breeds at most are used. The following generalized example will illustrate:

PLAN 1 -Two breeds
Breed A          -           Good body conformation
Breed B           -           Good body length

Breed A can used as the male line and Breed B may be used as the female line.
The cross may result in offspring manifesting desirable traits –of both parents. However the producer should also do the reverse type of cross because the reverse may result in a better type of offspring.
The plan can be shown as follows:
Male                            Female
A               x                B
B               x                A

PLAN 11 -Three Breeds
The producer may find that the single cross as outlined in Plan 1 results in offspring which manifest desirable characteristic of both parents. He may also wish to improve a trait for example, litter size. In this, case, it may be beneficial to introduce a third breed. Breed C may be introduced for this purpose. The plan may now be illustrated as follows:-

Male                            Female
A                x               B
A B     offspring
The third breed (i.e. Breed C) will then be crossed with females of the AB type as follows: -
Male                            Female
C                x               AB
CAB     offspring
This type of offspring is referred to as a three-breed cross because it is the result of crossing three different breeds i.e. Breed A, Breed B and Breed C.
However, this may not always result in the type which the producer desires. He may in fact, find that although he has improved his litter size, he may have lost some of the original desirable characteristics of good conformation which you will recall inherited from Breed A.
Therefore, rather than introducing a new breed, there is an alternative. This would entail the use of an individual of the same breed as one of the parents. This can be illustrated by the following example:
Male                            Female
A               x                B
AB offspring
Next, an individual of Breed A from which good conformation may be inherited, is mated with the cross-breed AB offspring as follows:-
Male                            Female
A                x               AB
AAB   offspring
This type of offspring is referred to as a back-cross. It is the result of mating a cross-bred individual with another individual of the same breed as one of the parents. In other words the breeder has back to one of the original breeds.
It is extremely important that the producer maintains complete and accurate records on the performance of every individual pig. It is the records together with keen observations which give the final answer. It has been found that: especially in swine, one can obtain exceptional results from specific crosses which combine well together .Therefore, the records and observations on the farm is the only answer to the producer who is on the alert for rapid improvement.
There are two methods of mating practiced in swine production - natural (hand or pen mating) and artificial insemination. Hand mating involves bringing the female and the boar together for mating. Under pen or pasture mating system a single female or group of females are penned with the boar for breeding for 3 up to 15 weeks depending on dry, bred sow facilities.
Mating is a prolonged process in swine, varying from 3 to 25 minutes, in which waves of high and low sperm concentration exists in the flow of the ejaculate. For this reason, it is important that copulation takes place without disturbance. 
Estrus in Swine
Importance of Estrus
Understanding and managing estrus in swine is important because estrus may be thought of as the starting point of the swine herd life cycle. Behavioral estrus lasts 2-3 days and ovulation occurs near the end of behavioral estrus. Knowing when estrus will occur, detecting it, and inseminating the female 12-26 hours after onset of standing heat (estrus) so that the sperm are deposited before ovulation will ensure high conception rates and low repeat breeders.
Effect of time of breeding on pregnancy rate in sows.

Managing the Basics
Estrus Synchronization Estrus onset is influenced by energy balance and nutrition during lactation. Weaning is used as an estrus synchronizing event in swine. When sows go into heat together, and conceive together, they will farrow their piglets together in groups which make all in/all out flow possible.
Signs of Estrus
  • The most definitive behavioural sign of oestrus is standing (primary) to be mounted by the boar. 
  • Sows in oestrus will often assume this rigid stance, called the lordosis reflex, when pressure is applied on the rump ("back-pressure") by the herdsman.
  • The group-housed sow actively seeks out the boar. 
  • The vulva lips are swollen and red with a thin, mucous discharge. 
  • Other signs (secondary) of oestrus include: depressed appetite, restlessness, alertness, pacing, grunting, and chomping of the jaws.
Estrus Detection Deficient estrus detection is the most important cause of infertility in breeding herds using hand-mating or artificial insemination (AI) systems. Typically, sows are checked for estrus once a day and gilts twice a day. In herds with estrus detection problems, heat checking sows twice a day is recommended. Estrus detection can be improved by observing sow behavior while the boar is given direct contact with the sow.
Refractory Sows However, sows and gilts will become fatigued and refractory to boar contact in less than one hour, even if they are in heat. This is due in part to the extreme exertion (isometric contraction) associated with standing heat. Thus, best estrus detection systems do not allow constant boar contact. For estrus detection in the absence of a boar, response to the "back-pressure" test can be potentiated (increase the effectiveness) by sex-odor sprays (ex. Boar-mate) or tape recordings of a boar.

Factors affecting Litter Size
There is a great deal of variability in the litter size occurring within and between sow herds. These factors are grouped under ovulation rate, fertilization and embryo mortality.
A.        Ovulation rate
  1. Breed- Yorkshire, Landrace ovulate more eggs.
  2. Heritability- Low estimates for litter size.
  3. Cross-breeding
  4. Puberty- Gilts will ovulate/shed more eggs at the second heat.
  5. Age of sow- increase in litter size at fifth litter.
  6. Flushing
  7. Hormonal control
B.        Fertilization Rate
  1. Estrus of breeding sow after weaning.
  2. Time of insemination. The life of sperm is an average of 24 hours and the life of the egg 6 hours. (See capacitation) If a sow is inseminated too early, the eggs might not be fertilized.
  3. Housing- sows and gilts should be grouped according to size and age.
  4. Boar. (heat exposure, overweight or over conditioned)

C.        Embryonic Mortality (Period of maximal mortality 8-16 days of gestation)
  1. Embryo mortality due to uterine disorder.
  2. Inbreeding
  3. Feed intake. (Too much feed immediately after service)
  4. Increasing maternal age
  5.  Reproductive diseases eg. Leptospirosis, bangs of brucellosis
  6. Overcrowding
  7. High environmental temperature
(Hafez p270 & other sources)

Causes of Pig Losses before Weaning            Percentages

General weakness                                           26.9
 Crushing                                                         19.2
Scours                                                                         14.2
Paralysis                                                          10.1
Rickets                                                                        5.3
Abnormalities                                                  4.0
Pneumonia                                                      3.3
Anaemia                                                          1.1
Other causes                                                    15.9

Heritability Estimates for Swine  (See Taylor p245
Important economic factors such as growth rate, feed conversion, litter size and carcass merit must be taken into consideration when selecting breeding stock. Not all characteristics are inherited to the same degree. Therefore select for characteristics which are fairly highly heritable. Improve the less heritable characteristics by improving your management.
This table illustrates heritability estimates of swine for some of these economically important traits.

Heritability Estimates for Swine

Heritability Percent

Loin eye area
Back fat thickness
Percent of ham
Percent lean cuts
No. of pigs farrowed
No. of pigs weaned
Weaning weight of litter
Post weaning gain
Feed efficiency
Birth weight


 (Cunningham and Taylor 349 & 246 respt)

Carcass characteristics are highly heritable. This means that a high percentage of superiority of one animal over another is transferred to its offspring. It also means that if you can identify the superior animal you can make fairly rapid progress towards improving these characteristics.
Feed efficiency and weight for age are only moderately heritable characteristics (low 0- 20%, moderate 20-40 %, high > 40%) (Cunningham pp348). You should not expect to make progress as rapidly in these characteristics as in highly heritable ones. Characteristics which measure a sow's performance, such as litter size, birth weight and weaning weight are less readily heritable. Improvement of these characteristics can most easily be secured by improving management practices. PS: H E varies among species example in beef and dairy cattle H E for birth weight is approximately 40% and sheep is 30 %

Artificial Insemination
This is a process by which semen is collected from the male specie processed, stored and then placed in the female’s reproductive tract by unnatural means.
  Artificial insemination offers the best of both worlds: It gives the producer the possibility to use the best boars while decreasing the amount of time spent breeding sows, thus allowing more effective use of the producer’s time. With a decrease in the number of boars on the farm, more space and food become available for sows without additional investments.
AI improves the genetic evaluation of the boars making their EBVs more reliable. It has also been demonstrated that AI cuts more than half the average time required to mate a sow or a gilt. As well, it also reduces the manipulations of the boars, which can sometimes be dangerous for the animal handler. Mating with AI is often easier on gilts and young sows that might be intimidated, especially by large boars.
The semen itself must be treated as any other perishable product. Soon after collection, semen quality starts decreasing. Insemination centers prepare the semen in such a way that an excellent quality can be maintained for a few days. The most important rules to follow for semen preservation are:

  1. Semen should be kept at 16 to 18 degrees Celsius until used.
  2. Avoid any temperature variation during preservation.
  3. Gently agitate the samples once or twice daily to prevent the sperm cells from accumulating at the bottom.
In these conditions, semen can usually be kept for 2 to 4 days without a major drop in insemination results.
No matter how good the semen is, no matter how well it is preserved, a sow can only conceive if she is inseminated at the right time. Thus, it is of utmost importance for the success of AI to have proper techniques of heat detection. Most new AI users improve their results in the first three months after introducing AI into the herd, mainly because they get better at detecting sows in heat. The best indicator of heat is the immobilization of the sow to back pressure.

1.      Maximum use is made of a valuable boar.
2.      It makes group farrowing possible without an increase in the number of boars. 
3.      Older boars may be used to breed gilts, because gilts are not required to hold up a heavy boar at breeding time.
4.      The useful life of boars may be extended as a heavy, aged boar will continue to work effectively on a dummy sow after he has become too large and awkward for natural breeding.
5.      There is a considerable saving of time if a large number of sows are to be bred (synchronization). 
6.      Introduction of new blood line without introduction of disease.
7.      Wide selection of high quality boars of all breed are available for improvement and cross breeding.
8.      Closed herd operation is possible.

Species           Average volume (ml)      Millions of sperm/ML    Potential # of mating / ejaculate
Bulls (Cattle)            2-10                                                          300-2,000                             100-600
Ram (Sheep)            0.7-2.0                                                      2,000-5,000                          40-100
Buck (Goat)             0.6-1.0                                                      2,000-3,500                          15-40
Boar (Swine)          150-500                                                     25-300                                   15-20
Cock (Chicken)      0.2-1.5                                                       0.5-60                                    8-12
Tom (Turkey)       0.2-0.8                                                        0.7                                          30          
(Source Cunningham pp269)

Great emphasis should be placed on the feeding and management of Breeding Gilts as these are the intended replacement sows that are expected to form a part of a profitable enterprise. In order to obtain maximum profits emphasis should be placed on reducing energy, and protein intake of breeding gilts. The potential to maximize profit in a farrowing operation may be interfered with by excessive feeding of gilts during pre-breeding, breeding and gestation periods. Gilts that are over fed immediately after breeding or throughout the gestation period suffer greater embryonic mortality, encounter more difficulties at farrowing, and will lose more weight during lactation than properly fed gilts.
Young gilts also need feed to grow and become mature sows. If the ration is inadequate, the sows will be ineffective in maintaining themselves and in producing strong litters. Weak pigs may result. Young sows may remain small or stunted in growth and be poor milkers. The feeding of a balanced ration in adequate amount during pregnancy is a must in profitable pork production.
Therefore, in order to realize maximum profits from a farrowing operation, it will be necessary to feed the gilts in such a manner as to reduce embryo mortality improved condition of the sow in the breeding herd, and assure no harmful effects on offspring development.

Feeding and Management
The age and condition of the gilt determine the amount and kind of a ration which she should receive. Thin gilts (body condition score 1&2) require more feed than do gilts in good flesh (B.C S 3-4). Large gilts need more feed than do small gilts, and young gilts must have more feed per hundred pounds of live weight than mature sows. The state of pregnancy also must be considered. .
Most gilt are full fed a 16% growing and/or a 14% finishing ration up to a weight of 180 to 220 pounds. The amount of grain desired during the gestation period varies with the age and condition of the animal. At this time gilts should be weighed and probed and the superior gilts selected as replacement breeding stock.
The amount of feed required by sows during the pregnancy period varies with the age, condition, and stage of pregnancy. Gilts should be put on a restricted daily ration after selection. A 12% dry sow ration should be limit fed at the rate of approximately 4-5 pounds per gilt daily during breeding and gestation. This ration will supply adequate protein for the developing gilt during this period. Tests conducted in Iowa, Illinois, Ohio, and South Dakota indicate that about 4 pounds of feed per day will result in maximum birth and weaning weights of pig. Ohio tests indicate that sows fed 5 pounds per day became fat. Those fed 3 pounds per day became weak and skinny. The amount of feed necessary will, however, vary with quality of ration, temperature, and condition of the sow or gilt.
The ration best suited to a particular farm must be based upon the kinds of feeds and forages available and the prices of feeds in the community. The key to feed efficiency is the use of high quality, cheap farm-grown feeds, properly supplemented with proteins, minerals, vitamins, and antibiotics.
During gestation gilts can make very effective use of good pasture of such plants as clover and alfalfa or other locally grow crops. Foraging on pastures will also provide some means of exercise that is desirable during the early stages of gestation. Breeding gilts need exercise as inactive, fat gilts rarely produce and raise good litters.
Gilts should have free access to water at all times. Plenty of water should be fed to gilts during pregnancy either in the form of slop feeds, in troughs twice daily, or in automatic waterers. Water is especially important during the summer when the temperature is high.
During the summer months pregnant gilts need shelter to protect them from sun and rain. This shelter should be dry and free from drafts and dust. bred gilts should have 11 to 14 square feet of shelter per head in cold weather and 15 to 22 square feet of shade per head in warm weather.

Age and Weight of Breeding
A farmer may decide that the small litters produced are due to the lack of prolificness in his breeding stock. Usually he is wrong in making this assumption. Small litters are very often a direct result of carelessness in the feeding and management of the herd at breeding time.
Gilts should be bred to farrow when they 7 1/2 -8 months of age if they have been well grown out. The maturity of the gilt is more important than its age. Most gilts which have done well reach puberty and came in heat when they are 5 to 6 months of age, while others may be at 11 to 13 months of age. Therefore the age to breed will undoubtedly depend on the breed of the gilt and other factors affecting its maturity.
Research studies with Yorkshires and Lacombe have shown that 80% of these gilts have regular heat cycle by 7 months of age and that the number of ova released remains constant for at least the first five heats. Producers should attempt to have gilts grown to 240 pounds by 6 1/2 months and breed on the first heat after that time. There would appear to be little justification for allowing mature well-grown gilts to have 2 or 3 heats before breeding in hopes of getting a larger litter. Thus, most gilt will have .produced their first 1itter before they are one year old.
It is better to breed the gilt during the first or second day of the heat period than during the last day (See diagram page 17). Larger litter may result from two services 24 hours apart.
Once gilts are bred, reduce daily feed intake to approximately 4 pounds of 12% dry sow ration until 40 days before farrowing. .At this time increase daily feed intake to 5 ½ lbs. of 14% dry sow ration or nursing sow ration daily.

The nutrients fed the pregnant sow must first take care of the usual maintenance needs. If the gilt is not fully mature, nutrients are required for maternal growth as well as for growth of the foetus. Quality and quantity of proteins, minerals, and vitamins become particularly important in the ration of young pregnant gilts, for their requirements are much greater and more exacting than those of the mature sow.  The aim is to keep the sow fit, not fat.
The gestation feed intake depends on the environmental temperature in which gestation occurs. The most meaningful way of expressing such a requirement is in terms of minimal level of gestation weight gain necessary for optimum reproductive performance.
The amount of gain desired during the gestation period varies with the age and condition of the animal. A gain of 70 to 90 pounds in gilts during pregnancy will allow for the growth of the gilt and her litter. Mature sows should gain from 60 to 80 pounds during gestation. These figures can be reduced somewhat if the litter is to be weaned when from one to three weeks of age. Pregnant first litter gilts gain about twice as fast as pregnant second litter sows. At farrowing first litter gilts will have a weight loss of approximately 35 pounds (weight of litter after birth, fluids).Second- litter sows will lose 40 pounds at birth. Nursing weight loss for 3 week weaning will be approximately 10 pounds on first litter gilts and 30 pounds on second litter sows.
Today more sows are raised under total confinement. Under confinement conditions different systems and types of feed are used. It also makes it easier to control feed intake and there is less injury to the sow due to fighting. The ration fed the sow has much to do with the type of litter which she will farrow. The ration best suited to your farm must be based upon the kinds of feeds and forages available and the prices of these feeds in your community. The key to feed efficiency is the use of high quality cheap farm grown feed, properly supplemented with proteins, minerals, vitamins, and antibiotic.

Feed Requirements during Gestation Period
The amount of feed required by sows during the pregnancy period varies with the age, condition, and stage of pregnancy. Normally the sow will be bred on the first oestrus cycle after weaning. Breed the sow when standing heat is first observed and again 24 hours later. This will result in a better conception rate. Record the breeding date (gestation period 115 days) .At breeding, the sow should be receiving approximately 5 pounds of 14% nursing sow ration daily.
Tests conducted in Iowa, Illinois, Ohio, and South Dakota indicate that about 4 pounds of feed per day will result in maximum birth and weaning weights of pigs. Ohio tests indicated that sows fed 5 pounds per day became fat. Those fed 3 pounds per day became skinny and weak. Limited feeding is recommended especially when environmental temperature is at 50 degrees or above. It is important that the condition of dry sows should be regulated so that they are neither to fat nor too thin at farrowing time. Overly fat sows may have difficulty in farrowing and give birth to weak or dead pigs. Sows that are too thin at farrowing tend to become suckled down during lactation. Thus, one way or another, limited feeding is a must for pregnant gilts and sows. This may be accomplished by adding sufficient bulk; by interval feeding; by group hand-feeding; or by individual feeding. In hand feeding the animal can be fed by hand the right amount of feed daily or self-fed a bulky ration. Either method may be used successfully.
The self-feeding method requires less labour, while hand-feeding usually takes less feed. In self -feeding the proportion of bulky feeds in the ration must be governed by the condition of the sows. Pregnant sows and gilts should receive about 1/2 to 3/4 pound of crude protein each day. It may be hand-fed in supplement or supplied in the self -fed ration. Plenty of water should be fed to sows during pregnancy. Water is especially important during the high temperature.
First 75 Days of Gestation Period
Breeding stock should be given a sow -weaner type feed. 'Slop' feeding is recommended. After breeding, feed intake should be restricted to approximately 4-5 pounds of 12% dry sow ration daily. This ration should be a high energy ration (TDN 75%).Once a day feeding is adequate for bred gilts and sows. Diet can be regulated by using individual feeding stalls or sow tie stalls.
During the early stage of gestation it is desirable to have the sows forage in the pasture. Brood sows need exercise, and if they do not rustle out into the fields themselves, they should be fed at a distance. Exercise is essential to avoid sows becoming fat. Inactive, fat sows f1rrow smaller litters and crush more pigs. Exercise also helps to prevent constipation in Sows at farrowing time. If some of the sows, are in poor fleshing, or if weather, conditions are cold, feed intake will have to be increased. Sows must be relatively free from parasites and be kept under suitable environmental conditions. Sows should be washed with insecticide to remove lice and mites. Gilts and sows should be kept in an area, where the temperature does not fall below 50°F. They also need shade, to protect them from the sun and rain. The house should be dry and, free from drafts and dust.

40 Days Before Farrowing
Approximately two -thirds of' the growth of' the foetus is made during the last month of the gestation period; therefore, this is when the nutrient needs of the sow are the greatest. Again, the increased needs are primarily for proteins, vitamins, and minerals. During gestation, it is also necessary that body reserves be stored for subsequent use during lactation with a large litter and a sow that is a heavy milker,  the demand for milk production are generally greater than can be supplied by the ration fed at the time of lactation. Therefore, the daily feed intake should be increased from 4 pounds to approximately 51/2 pounds of 14% dry sow ration, 40 days before farrowing.

3 to 4 Weeks Prior to Farrowing
Vaccines against E. coli scours could be useful if available. This could be given at least 4 weeks before farrowing to ensure the presence of antibodies in colostrums to protect piglets. The breeding stock should also be vaccinated against Swine Erysipelas and Pasteurella annually. Stocks should have a routine warming 3 to 4 weeks prior to farrowing. This will allow the sow to be free of worms prior to entering the farrowing quarters. Faecal examination should be done to determine the amount and kind of worm infestation in the herd.
One-Week Prior to Farrowing
Sows and Gilts should be placed in farrowing quarters one week before she is due to farrow. Farrowing quarters must be properly disinfected before sows and gilts are introduced. The sow and pen should be washed regularly to keep her and the surrounding clean. Spray or dust the sow for external parasites such as lice and mites if necessary.
It is considered a good practice to feed lightly and with bulky laxative feeds from 4 to 5 days before and after farrowing. Dilute gestation ration with 25% bran or oats, one week prior to farrowing. The bran or oats helps avoid constipation problems in the sow at farrowing, feed 51/4 pounds of this ration daily. The animals may be watered at frequent internals before or after farrowing, but in no event should she be allowed to gorge.

3 Days Prior to Farrowing
Sows and gilts should be washed with warm water and soap and rinse with a mild disinfectant.  In washing the animals particular care should be taken to remove the small plug of dirt that may be on the end of the teats. Sows and gilts should be placed in farrowing crates or pens to permit them to become adjusted prior to farrowing. The farrowing quarters, should be thoroughly cleaned, disinfected, and allowed to stand idle for approximately 10 days to help break the disease cycle. The farrowing quarters should be free of drafts and warm (55 to 70oF} .A newborn pig chills easily. The use of a heat lamp will overcome this problem.

Farrowing Day
Although most sows do not need assistance at farrowing time it is a good policy to be on hand .Sows become nervous as they approach farrowing time and pile up bedding materials. Most sows farrow within 24 hours after milk develops in the nipples.
The sow requires no feed for 12 hours after farrowing. Provide warm (50 to 60°F) clean water only.
The gestation -lactation period is a critical one in swine nutrition. It is now known that the feed and care accorded the broad sow materially affects conception, reproduction, and lactation.  The successful producer plans carefully for the practice which will be followed during each of these periods.  If he fails to care for the sows properly during any one of the periods, serious losses may result

A critical element of successful swine reproduction is managing sows so they do not gain or lose too much weight or body condition between parities. Maintaining sows in proper body condition throughout their lives can lead to more consistent reproductive performance, but inadequate control of sow body weight and condition can lead to farrowing difficulties, poor rebreeding performance, and high culling rates. In addition, the direct economic impact on annual feed costs of underfeeding or overfeeding sows can be substantial.
Individual operations vary in terms of animal genetics, environmental conditions, and management. Therefore, it is important to monitor sows on individual farms to determine the adequacy of current feeding management practices.
 This scoring system can  be used to determine individual gestation feeding levels to achieve a target condition score at farrowing.

Sow Body Condition Scoring System

This scoring system uses finger or hand pressure at key reference points on the sow’s body to arrive at a number, or score hence the name sow body condition score. The points used on the sows body are those areas where the only tissue between the skin and bones is fat tissue. These areas on the sow include the ribs, back bone, H bones, and pin bones (Figure 1). By assessing the ease or difficulty of feeling these bones, you can estimate the fat stores of the sow. It is important to rely on more than one of these areas when assessing body condition. Different animals may deposit fat in differing degrees at different locations.
A condition score from 1 to 5 is assigned to each sow, based on the ease or difficulty of detecting bones at various pressure points. Figure 2 illustrates the physical appearance of sows for each condition score and describes the ease or difficulty of detecting the bones for each score. An approximate level of back fat associated with each condition score is given in Table 1. The goal is for sows to attain a condition score of 3 by mid-to-late gestation and to maintain that score until farrowing. Sows with a condition score of 3 at farrowing will enter the farrowing crate with adequate fat reserves to withstand a heavy lactation, but they will not be so overconditioned that they will experience farrowing difficulties or reductions in lactation feed intake. Sows entering the farrowing house with a condition score of 3 should eat well, milk well, and have a condition score of 2.5 at weaning, resulting in a prompt return to estrus. A realistic goal is to have all sows in a farrowing group with condition scores between 2.5 and 3 at farrowing, with 80% scoring 3.

Table 1. Relationship between condition score and back fat level.
Condition Score
Approximate Level of Back Fat (Inches)
< 0.6
0.6 - 0.7
0.7 - 0.8
0.8 - 0.9
> 0.9

Frequency of Condition Scoring Sows

For best results, sows should be condition scored at mating and at least two additional times between breeding and farrowing. It is often convenient to combine condition scoring with other routine activities, such as pregnancy checking and vaccinations, to save time. A typical procedure is to score sows at mating, on day 30 post-mating when sows are pregnancy checked, and about 80 days after breeding. Condition scores will be more accurate if two people score the sows and the resulting two scores are averaged. When this team approach is used, the same individuals should always score the sows so scoring will be consistent.
It is important to record condition scores so that monitoring the sows progress is possible. One convenient way to document a sows condition score is to record the score on her information card. Another option is to develop a card similar to that shown in Figure 3 and simply circle the drawing that best represents the sows condition at the time of evaluation.

Number of Sows to Condition Score

It is generally best to condition score each sow individually, especially in herds with no recorded history of condition scoring, those in which sow condition is poor, and in herds that are experiencing reproductive difficulties. Once sow body condition within a herd has stabilized at a desirable level or a feeding management strategy has proven satisfactory, it may be sufficient to establish a condition score monitoring program rather than continuing to score all sows in the herd. For a monitoring program, at least 15 to 20% of the sows in each farrowing group should be condition scored.

Using Condition Scores to Adjust Feed Intake

When using body condition scores to adjust feeding levels for sows, it is important to define an operations base feeding rate. A base feeding rate represents the amount of feed which will allow a sow to gain the proper amount of weight and condition during gestation, assuming she has a condition score of 2.5 at mating and is not subjected to extreme environmental conditions. For most operations, a base feeding rate during gestation of 4.5 to 5 pounds per day of a corn-soybean meal diet is adequate.
During lactation, some sows may lose considerable body weight and condition, resulting in a condition score of lower than 2.5 at weaning. These sows will need more feed than the base feeding rate to achieve proper condition by the next farrowing. Other sows may be over-conditioned at the time of weaning and will need less feed than the base feeding rate to achieve the desired body condition score by the next farrowing.
It is best to identify at the time of mating sows that will require more or less feed than the base feeding level in order to reach the target condition score by farrowing. The advantage of identifying these sows early in gestation is that ample time will be available to get them into proper condition. In general, it is best to condition sows during the first half to two-thirds of gestation so that large adjustments in feeding rates are not necessary close to farrowing.
Table 2 shows some guidelines that can be used to adjust the daily feed allowances of gestating sows based on their body condition score. Keep in mind that these adjustments are only guidelines. Animals on different farms may require more or less feed to achieve target condition scores based on their genetics, environmental conditions, and farm management practices.
Table 2. Guidelines for adjusting gestation feeding level based on condition score.
Condition Score
Feeding Level (Pounds)
Base feeding level + 2.0
Base feeding level + 1.0
Base feeding level
Base feeding level - 0.5
Base feeding level - 1.0

Farrowing Facilities

These litters are less than 1 hour old. Note the blue bars running across the sows' sides. The side bars on these crates exert inward tension, so that the female must use her weight to push them apart in order to lie down. This helps prevent the sow from flopping down on the piglets. In addition, the bars must be spaced to ensure access to the udder for the piglets.

Farrowing almost always (all in all out) AIAO so sows are grouped to farrow on the same day. Rooms are sized to accommodate 1 group. The number of rooms is dictated by:
  • frequency of farrowing (weekly, semi-weekly, bi-weekly, monthly)
  • weaning age.
 The number of farrowing groups is dictated by:
  • frequency of farrowing
  • farrowing interval

This sow is alert and sitting up. She was moved into the farrowing room about one day before her due date. Note the heat lamp in the crate behind her; the neighbouring sow already has a newborn litter.

Care and Management During and After Farrowing
Some producers maintain that the care of the sow during gestation and the care of the pigs through the first few days of life account for more than one-half the job of raising pigs.
Normally, healthy sows will usually farrow without trouble. If possible, someone should be on hand at farrowing to offer any needed assistance, that is, preventing pigs from chilling by placing them under the heat lamp, or starting breathing in apparently lifeless pigs by removing the membranes from the nose and applying gentle rhythmic pressure over the ribs in an attempt to get the pig breathing.
Some sows will farrow very quickly while there are sows that will take a much longer time. The farrowing of a good sized litter can be completed in about 60 minutes. A long farrowing period will cause more pigs to die or be weakened during farrowing.
Oxytocin may be used to speed up farrowing. However, there are several precautions which should be observed.
  1. Oxytocin should not be given until the cervix is relaxed. As soon as one pig is born, then the cervix is relaxed. If oxytocin is given before this it could cause the uterus to be torn.
  2. If several pigs have been born, farrowing may be stopped by a pig stuck in the birth canal. The procedure is to reach into the birth canal, after proper cleaning of your arm and feel if it is open. If one pig has been born and the birth canal is open, the drug oxytocin can then be used to speed up farrowing and save more pigs. A person should not enter a sow unless he has been instructed on how to do so properly. The possibility of introducing infections into the sow at this time is great.
Unskilled persons should rely on the assistance of others who know how to do so properly. If there appear to be complications in farrowing, a veterinarian should be contacted. When farrowing is complete, the afterbirth and fluid should be removed immediately from farrowing quarters. The hindquarters and udder of the sow should be wiped clean again immediately after farrowing, if the sow had become dirty with blood, fluids, etc, during farrowing. A clean sow is less likely to infect newborn pigs.
A weight loss of 5 to 10 pounds during the first three weeks of lactation is acceptable for the first- litter gilts. Second- litter sows may lose 25- 30 pounds during the same period. The larger the litter nursed, the greater the weight loss. The normal temperature of the sow is 101o +1 for the week prior to farrowing.
The temperature can increase to 102.7°F + 1.3° just before farrowing, and for 2 or 3 days after farrowing. Normal healthy sows can have a temperature of 104°F during 48 hours immediately after farrowing and no treatment should be initiated on the basis of a high temperature alone. If other signs such as reduced appetite, abnormal milk flow or abnormal discharge from the vulva are present, treatment is indicated. M.M.A. Syndrome (Metritis Mastitis, Agalactia) may occur 1-2, or more days after farrowing. A veterinarian can best advise no treatment. A rectal thermometer can reveal abnormal temperatures.
Farrowing is the most critical time in pig production. The importance of good sanitation, along with common sense and alertness by the operator, is obvious.
Feeding during the Nursing Period  
On day of farrowing, sow will eat very little. Normally the sow will be receiving approximately 5 1/2 pounds of 14% dry sow ration containing 25% bran, one week prior to farrowing.
After farrowing, provide the sow with a 14% nursing sow ration. This ration can be fed to appetite in two one -hour feeding per day or self fed. The sow may be fed the same ration the three days after farrowing as the three days before. It is usually best to feed about a half -ration the first day and increase the ration gradually- until she is on full feed. Heavy milking sows should be hand fed for the first week after farrowing. Other sows may be self -fed. Nursing sows can consume 10 to 15 pounds of 14% nursing sow ration daily. As weaning time approaches, feed intake can be cut back to reduce milk flow. Adequate water should be provided at all times. A nursing sow may consume 40 to 50 pounds (4 to 5 gallons) of water daily. There are several problems which may arise during the management of nursing sows. Some sows may fail to produce milk. This may be due to a number of causes such as, run down condition at farrowing time, inadequate diet, or inherited traits. Again mastitis or udder oedema might be present. This leads to tenderness of the udder with a tendency for the sow to prevent the pigs from sucking. The milk supply later dries up. Fatty deposits in the udder, a consequence of faulty feeding during pregnancy can also impede the secretion of milk.
Diets consisting of mainly corn, banana, potato or other root crops, which are too high in carbohydrates and too low in protein will lead to milk shortage. A good lactating sow will produce an average of about one gallon of milk daily during her suckling period. A sow's milk is also richer than cow's milk in all nutrients, especially in fat. Thus, sows suckling litters need a liberal allowance of concentrates rich in protein, calcium, phosphorus, and vitamins.
Sometimes a sow refuses to own her litter, due most frequently to pain or irritation; it is more common in young gilts at first farrow. When this occurs the pigs should be removed for a few hours. Then a few should be placed outside the gate of the pen. Their squealing and desire to suckle might attract the attention of the mother and if she comes to the gate and shows interest, they might be placed with her. If she lies down and let and lets them suckle, the other piglets can be placed with her. However she should be watched for some time until she appears to have completely accepted them. Injectable tranquilizers are available to calm excited animals.
Sometimes a sow will kill her pigs as they are born. This could be due to pain or a deficiency in the diet during pregnancy, such as a shortage of animal’s protein in the ration. It is advisable to fatten such sows for slaughter instead of keeping them in the breeding herd.

Re-breeding Sows
Generally sows will come into heat 5 to 7 days after weaning occurs. Depending on the intensity of the farrowing schedule, sows can be re-bred on the first heat period, or can be passed over to the next period 18 to 24 days later. Sows should be bred when standing heat is observed and again 24 hours later. This will result in better conception rates.  

Farrowing Day
An attendant should be present, if possible, when farrowing occurs. Quick, confident attention will save pigs. Young pigs are sometimes born with mucus membranes or mucus covering their nostrils. This should be removed quickly to ensure breathing. If the newborn pig is not breathing, gentle rhythmic pressure over the ribs may start the breathing process. Shock treatment -immersing the newborn in cold water to start it breathing is also used by some swine producers.
The newborn pig chills easily, coming from womb temperature of 102°F to barn temperature of 70°F or less. The newborn pig should be able to get under heat as soon as possible after birth.
Thorough sanitation must be maintained in the farrowing pen. All soiled bedding and dirt should be removed and replaced with fresh clean bedding. It is important to keep the area dry and clean.
Bleeding Navel
If this is a problem, tie navel. Sometimes the navel cord is long and it is impossible for the pig to move about freely. If necessary, tie the navel cord and cut off about two inches from the body. Then dip the end that has been cut in tincture of iodine solution. The navel should be examined and treated regardless of the length of the cord. It may be necessary to tie the cord if bleeding continues.
Check vitamin K level of sow feed. Feed should contain a minimum of 2 grams of added vitamin K per ton of complete feed.

Navel and Joint Infection
Normally the infection settles in joints, and causes swelling. Prevent infection entering the body through the navel by dipping navel in mild disinfectant. If infection enters the body through skinned knees from the nursing process, check floors for roughness. A rubber mat may help. Some producers use an antibiotic injection to counteract infection from navel and/or skin abrasions.
The newborn pig should be encouraged to nurse as soon as possible to enable it to build up antibodies for greater resistance to infection. Colostrum, the first milk after farrowing, is a good source of antibodies and protein. Each teat should be stripped out to clean the teat canal of foreign matter before pigs are allowed to nurse. This can be done when the sow starts to farrow.

Needle Teeth
Needle or black teeth should\be removed at birth. The c1ipping of needle teeth is a controversial issue. Some producers do not clip the teeth because they believe that the mouth and gums may be injured, allowing infections organisms to enter the body. However, the practice, if done properly, will not cause disease infections. It may even prevent them, because, when fighting, pigs will not be able to inflict wounds upon each other's faces that often permit necrotic and rhinitis organisms to enter the body. If the needle teeth are not removed the pigs will also cut the sow's udder and thus providing sites for possible infection.  Clipping should be done with a pair of cutters in such a way that there is a clean, smooth break with no injury to the gums and no jagged edges. Side-cutter pliers should be clean and disinfected before use. 

Ear -notching
Breeders of purebred hogs, and many commercial producers make a practice of notching the pigs' ears at farrowing time. It is the most practical method of identifying the pigs of a litter so that the productiveness of a sow can be determined and considered in the selection of breeding stock. All sow -testing programs begin with ear- notching of the pigs. Most producers number the litters in the order in which they are farrowed. The notches may be made using a notching instrument or scissors.
Purebred breeders and swine research specialists may wish to make each pig so that it can be identified by litter number or by number within litter.

Treating Tails
The tails of young pigs may become wet and chapped. Mange or other infections may enter the breaks in the skin and cause the loss of the tails. Although, hogs without tails or with short tails bring the same price at the packing plant as do pigs with tails, buyers of purebreds and exhibitors of pigs prefer animals with tails. The loss of tails can be avoided by keeping the bedding quarters dry, warm and free from drafts, and by coating the tails with vaseline or a medicated salve.

Transfer of Nursing Pigs
Pigs may be transferred to even -up litters. Pigs must receive colostrum milk before transfer is made. Transfer the strongest pigs from the large litters to the small litters. Very small and weak piglets, under 2 pounds in weight, should be killed at birth. A desirable birth weight is from 2 1/2 to 4 pounds.

Anaemia Prevention
Injectable Iron
Usually 1 to 2 cc of injectable iron given in the ham at 2 or 3 days of age will prevent anaemia (follow manufacturers direction).
Oral Iron
10% ferrous sulphate added to a simplified starter in the meal from 1ounce ferrous sulphate and 9 pounds starter can be used to prevent anaemia.
One -half pound of ferrous sulphate starter meal is placed on the floor in the creep area when pigs are 4 days old and twice per week thereafter until pigs are 3 weeks old or can consume dry feed. Newborn pigs obtain an average of 47 mg of iron and require 7 mg daily for normal growth. The sow’s milk contains an average of 1 mg per litter. Therefore it is recommended that the diet of body pigs contain a minimum of 80 mg.

Docking of Tails
Tail Docking reduces the problems of tail biting. Approximately one inch of the tail should be removed with a pair of side cutter pliers when the baby pigs are 2 to 3 days old. Removing only the tip of the tail, or insensitive portion, seems to eliminate tail biting in most herd, although some pork producers prefer to remove the tail close to the body.

Male pigs should be castrated at 7 to 10 days of age. Castration at this age keeps stress to a minimum. The later they are castrated, the greater the set-back. Under no condition should the pigs be castrated, wormed, vaccinated, or weaned at the same time. These operations should be spaced at two -week intervals.
Unless heat is provided by the use of brooders or heat lamps, pigs should be castrated when the weather is warm. The pen and hog house should be clean, dry, and well bedded.
Before castration begins the scrotum should be washed with a mild antiseptic solution or with soap and water. The sharp knife used in castration and the operator's hands or rubber gloves should be carefully cleaned and disinfected. Usually after the operation disinfectant (iodine) is applied to the area.
At castration time replacements should be identified. Also look out for abnormalities that might disappear as pigs grow older.

Vaccination and  Deworming
Vaccination of pigs for cholera has been a common and necessary practice for years. At 6 to 8 weeks inoculate pigs against Swine fever and at 8 weeks against Erysipelas. Additional vaccines are available against E. coli scours, pasteurella, pneumonia and atrophic rhinitis. At 6 to 8 weeks, piglets are wormed and weaned.

Controlling Internal Parasites in Swine

Whether pigs are raised in confinement or on pasture, controlling internal parasites is essential to the overall herd health program. (Recent studies by Tom Kennedy of Research, Inc, Waunakee, WI,) have shown that worm infestation is prevalent on both a farm and individual pig basis. Of the farms examined, 91 percent raised pigs on concrete, wire or slotted floors, but more than 90 percent of all farms were infested with one or more kinds of worms.
Worms reduce growth rate and feed efficiency, and damage tissues, predisposing pigs to infection by other diseases. Economic loss also will be incurred when affected tissues are condemned at the slaughter plant.
 Eggs of (Large Roundworms) Ascaris suum are small-about the diameter of a human hair and almost invisible. Eggs can withstand severe cold, dryness, most chemical disinfectants and can live at least seven years in soil. The eggs pass from pigs in manure. When they leave the body with the feces, they are in an early stage of development and are infective. Within a few weeks a tiny larva develops inside the egg.
Pigs become infested by consuming food and water contaminated with infective worm eggs. When a pig swallows ascarid eggs, the shells rupture in the intestine and larvae are liberated. The larvae burrow through the intestinal wall and enter the blood stream, which carries them to the liver. From the liver, larvae travel in the blood through the heart to the lungs where they burrow through lung tissue and enter large air passages. The pig coughs and forces worms into the throat where they are swallowed and passed into the small intestine--this time to mature and grow to adults. It takes about four days for larvae to reach the liver, nine days to reach the lungs and 15 days to complete the trip to the intestine. Worms grow to egg-laying adults in about 60 days.
Clinical signs of roundworm infestation are primarily associated with larval migration through the lungs. Pigs have a dry cough, loss of appetite and weight, rough hair coat, increased temperature, and an increased rate of respiration.
Both young and adult worms cause damage. Young worms destroy liver tissue, causing abscesses and scars. In the lungs they penetrate blood vessels, destroy tissue and plug smaller air passages. Damage to the integrity of the lung tissue predisposes pigs to pneumonia. Adult worms in the intestine rob the pig of food, block the gut and excrete substances which interfere with digestion.
Diagnosis is made by microscopic identification of eggs in the feces. Adult worms in the intestine and scars in the liver are seen on postmortem examination.


Trichuris suis, is called the whipworm because it is shaped like a whip. A mature whipworm is 1 1/2 to 2 inches long. It has one of the simplest life cycles known. Eggs are laid in the large intestine and pass from the body in manure. They develop into infective larvae in 21 days. After being swallowed by a pig, the young larvae burrow into the wall of the large intestine. Within a few days, the young worms emerge, attach to the lining of the large intestine and grow to maturity. A life cycle lasts 70-90 days.
Whipworms cause considerable inflammation and irritation of the intestine. Whipworm infestation is characterized by loose stools which in many cases progresses rapidly to a severe, bloody diarrhea. Diagnosis is made by finding worm eggs in the feces or by recovering worms at necropsy (examination after death). If sexually immature worms are causing the damage, eggs may not be found in the feces.


There are three species of Metastrongylus or lungworms. Lungworms are thread-like, white worms up to 2 1/2 inches long. Female lungworms live in air passages in the lungs where they produce large numbers of thick-shelled eggs, which the infected pig coughs up, swallows and passes in manure. Earthworms swallow the eggs, which hatch in the earthworm's intestine and become infective in three to four weeks.
Pigs become infested by eating earthworms which harbor the infective larvae. Lungworm infestation causes coughing and shallow breathing. Hemorrhages occur on the surface of the pig's lungs during early stages of lungworm invasion. Constant irritation by lungworms can bring about consolidation of lung tissue around sites occupied by worms. Tips of lungs become grayish or whitish and very hard in some cases. Secondary pneumonias are common. Pigs infected with lungworms tend to go off feed, become unthrifty and fail to grow.
Diagnosis is made by isolating eggs or larvae from feces or by demonstrating larvae in nasal secretions. Frothy mucus may be found at necropsy. When it is collected in a dish containing water and examined microscopically, the worms are easily observed.
Prevent lungworm infestation by keeping pigs in lots where they cannot contract earthworms. Earthworms thrive in old hog lots in which manure and litter have accumulated, or on permanent pastures and in low fields that receive drainage from higher ground.

Nodular Worms

The nodular worm, Oesophagostomum dentatum, is a small, whitish worm about 1/3 to 1/2 inch long that lives in the large intestine. Worm eggs pass from the pig in manure and under favorable conditions of moisture and temperature, develop to form infective larvae in three to seven days. These larvae can survive up to 10 months in mild climates but will die in cold temperatures. These parasites survive by wintering in breeding stock. The pig will eat infective larvae with feed or water. The worms encyst in the lining of the large intestine and cause nodules to form. This condition is called "pimply gut". Within six to 10 days after infection, the young worms emerge from the nodules and grow to maturity. The life cycle requires 50 to 53 days.
These immature worms can cause loss of appetite, diarrhea or constipation, and anemia. Diagnosis is made by microscopically identifying the characteristic worm eggs in the feces, or by recovery and identification of adult worms at necropsy.

Anthelmintics for Swine

When selecting a dewormer for swine, consider these five factors: (i) efficacy of compound (ii) spectrum of activity (iii)  mode of administration (iv) margin of safety (v)  cost of treatment. The spectrum of anthelmintic activity determines the number of species affected by the dewormer. Certain swine anthelmintic drugs are highly effective against only one species. If the herd problem involves several species of parasites, use a dewormer that effectively removes many species.

Prevention and Control

Since moisture favors the development of worm eggs into larvae and dryness kills them, reduce moisture to decrease parasitic contamination. Pastures should be well drained and feeding areas should be raised above ground. Many worm eggs can survive for long periods in dirt. Research has shown that ascarid eggs on unplowed pasture lots remained infective for seven years--whipworm eggs can remain infective up to six years. Rotating hog lots will help prevent infestation.
Worm eggs are easily carried by the wind or water and have been recovered from soil on roofs, window sills, and sides of buildings.

Table II. Approved claims of principle dewormers (listed alphabetically by trade name)

Types of worms controlled

Atgard (dichlorvos)
  • Mixed in feed and fed
    for 1 to several days,
    according to directions,
    to pigs of any age
  • Top dressed on feed for 1 day to sows, boars, gilts
Banminth (pyrantel tartrate)
  • Continuous use in feed,
    96 g/ton, or a 1 day treatment in feed at 800 g/ton
L3, L4
  • 3 day treatment 96 g/ton
Hygromycin B
  • 12 g/ton continuous
    in feed
Ivomec (ivermectin)
  • Subcutaneous injection
    300 µg/kg
L3, L4
Levasole, Tramisol (levamisole)
  • 1 day treatment in feed,
    water, or oral gel
  • 50 mg/lb body weight
    1 day, in water or feed
Safe-Guard (fenbendazole)
  • 1.36 mg/lb body weight in feed/day, 3 to 12 day treatment
L3, L4
L3, L4
L3, L4
TBZ (Thiabendazole)
  • Fed continuous 45.4 to
    908 g/ton
on dose
TBZ paste (Thiabendazole)


L3 = Third stage larvae are those that migrate (liver, lungs or within tissue)
L4 = Fourth stage larvae are those immediately preceding adulthood (in the gastrointestinal tract)
Atgard is a product of Fermenta Animal Health; Banminth is a registered trademark of Pfizer, Inc; Ivomec and TBZ are registered trademarks of Merck and Co.; Levasole is a registered trademark of IMC/Pitm
Provide a source of clean water when pigs are approximately 5 days old. They will drink a considerable quantity of drinking water during this period (1- 3 weeks old). Ensure that water has not become stale or taken on pen odours.

Creep Feed
Baby pigs should have access to a creep feed beginning at 7 to 10 days of age. Nursing pigs consume very little creep feed before they are 3 weeks old. A small quantity (approximately 1/2 pound) of 20% creep feed should be provided on the floor in the creep area. Increase the feed as consumption increases. A quantity of the creep feed should not remain in the creep area for more than 24 hours. If feed has taken on pen odours or has become rancid it is not palatable to the young pig.
Feed approximately 5 pounds of creep feed per pig, if pigs are weaned at 6 weeks of age. If early weaning (3 weeks) is practiced, pigs are fed creep feed until they reach a weight of approximately 25 pounds and are then changed gradually to a starter feed. Total consumption of creep feed with early weaning is approximately 20 pounds per pig.

Starter Feeds
Pigs should be gradually changed to starter ration after pigs have consumed most of the creep feed, 5 pounds or 25 pounds (early weaning). Pigs are generally fed a starter ration until after the weaning process has been completed, and weight is approximately 50 pounds. At this time they are gradually introduced to a 16% grower ration.
Some swine producers feed growing pigs a 16% all purpose ration from birth to market. If this ration is a high energy ration, such as corn as a grain source, performance has been satisfactory.

Early Weaning
Weaning should not be done at 3 weeks, unless sows can be re-bred within one week of weaning. Early weaning normally requires superior facilities and management practices.
With the use of fortified pre-starter, starter, and grower rations, it is possible to wean the pigs in advance of the usual age of eight weeks. Swine specialists are convinced that early weaning of pigs will reduce loss by death of pigs, prevent large losses in weight of the sows and permit earlier re-breeding of the sows. They also think that early weaning will reduce the number of runts, prevent spread of disease from the sow to the pigs, economize on feed for the sows, and save labour. Also, less floor space is required when pigs ere weaned early.
Early weaning of pigs requires special, rations which must be carefully formulated. These rations are expensive end not all pig producers are willing to buy or mix these highly fortified feeds. When they try to wean early and feed ordinary rations, the results are shocking, good management is essential to successful early weaning of pigs. Man must assume full responsibility when the sow is removed from the litter. Early weaning require better than average management. The sow may be able to do a fair job of raising the litter even with inadequate equipment.
The feed intake of the sow should be reduced approximately 7 days prior to weaning, when 4 to 5 week weaning is done. This reduces the sow's milk flow and nursing pigs consume more dry feed. Remove sow from pigs if possible to reduce weaning stress.

After Weaning is Complete
Treat for mange and lice if necessary. Worm pigs if necessary. If after -weaning scours is common in the herd, preventative medication should be employed.

From the production stand point, the period from weaning to market is an important one since more than twice as much capital is involved in growing out pigs as is involved in producing weaning pigs. The efficient pig raiser plans carefully his production program. He provides adequate rations and feeds them in the proper amounts. He uses the methods of feeding best suited to his farm situation. He provides pasture of good quality in the desired amount. He is efficient in housing his pigs and in controlling disease and parasites. The profit from the enterprise is determined by the cost of production and by the selling price. Usually he can influence the cost of production more easily than he can the selling price.
The Digestive System of the Young Pig
Birth to Three Weeks
The very young pig, up to three weeks of age, has a limited ability to readi1y digest carbohydrates found in cereal grains. The young pig is mainly able to digest milk products. If the young pig consumes a large quantity of carbohydrates these pass into the large intestine and bacterial fermentation occurs resulting in scours. Creep or starter feds used during this period should contain some milk products, such as skim milk and/or whey.
Four weeks of Age
Between three and by four weeks of age, a mature digestive system develops, capable of digesting corn, other grains and soyabean.
Baby Pigs Scours
The gut of the normal pig contains strains of Escheria coli bacteria, as well as other bacteria. These bacteria live on the food that is eaten by pigs. The E.coli bacteria releases toxins which can irritate or damage the walls of the intestine if produced in large enough amount. Changes in can feed lead to an increased production of the bacterial toxins. This indigestion reaches a peak 7 to 10 days after weaning or after a change in feed. The end result is diarrhoea or scouring.
Therefore to prevent scouring, the feed change should be made gradually (3-4 days). The feed intake should be restricted and the pigs kept slightly hungry at weaning. The initial reduction in growth rate is more than compensated for later on. Some producers tend to over-feed newly purchased weanlings. Where feed cannot be restricted, some pig producers dose with Epsom salts (at a rate of 2 ounces per gallon of drinking water) the day after weaning and again 5 to 7 days later. This flushes out bacteria and toxic products. Antibiotics and/or lactic acid are used to reduce bacteria.
Reducing Weaning Stress
Weaning on most farms at 4 to 5 weeks of age seems the most practical. This will result in 2.25 litters per sow per year. Some producers are successfully weaning at earlier ages. This practice however, depends on the condition of the pigs and the quality of husbandry. If possible the sow should be removed at weaning, allowing the weaned pigs to remain in familiar surroundings for a few days.

Space Requirement
Two litters comprising of approximately 20 pigs may be allowed to run together for about one week prior to weaning. This group however, is not mixed with other pigs throughout the growing and finishing period. They can be put in 16 by 5 foot pen in the farrowing and finishing barn to a weight of 110 pounds (4 sq ft each). At this time half of the group, the males or borrows can be put in a pen of similar size to market weight (8-9 sq ft each). Boars will gain 10 % faster than gilts & 5% faster than borrows, and normally will be marketed before gilts of the same age.  

Temperature and Ventilation
Room temperatures from weaning to approximately eight weeks of age should be maintained at 700 to 850 F. The ventilation system should be adequate to provide fresh air whi1e maintaining suggested temperatures. Pigs can be removed to feeder barn at eight weeks or at a weight of approximately 50 pounds.  

Feeding Program
Age Two Weeks
The young piglets should be fed an 18% creep or starter ration (containing some milk products) when they are about 3 weeks old. Usually a small amount is spread on the floor of the creep area daily. The quantity of the feed should be increased gradually. Old feed should be removed every 24 hours so that it will not be consumed. Clean adequate water should be provided.
Age Four to Five Weeks
At four to five weeks the piglets can be weaned. For approximately 10 days after weaning they should continue to receive the 18% starter ration. The appetite should be kept keen by restricting the feed intake slightly at weaning.
Age Six Weeks.
Pigs can be gradually changed to a 16% grower ration approximately 10 days after weaning. The change should be made gradually to reduce digestive problems.

Selling of Weaner Pigs
In farrowing operations weaners are normally sold at eight weeks of age, weighing 45 to 50 pounds. If weaners can move directly from the farrowing operation to the feeder operation, stress is reduced. If the purchaser of weanlings knows how the weaners have been handled, type of feed used, etc, he can adopt similar feeding practices, and reduce weaning stress.
Eight Weeks to Market
Due to the relatively high cost off grains and protein pigs may be fed on lower protein level rations. Different protein sequences can be used to produce a market hog, 180 pounds carcass at least possible cost. Research has indicated the following:-
top unloading silos one to two inches during the summer months to prevent spoilage.

Tail Biting
Tail biting may occur when pigs are under stress. Some causes of stress are overcrowding, limit feeding, changes in ration, unpalatable feed, unbalanced rations, shortage of water, hot and/or cold temperatures, poor ventilation, etc. Generally, although tail biting can be considered an alarm system, indicating that something is wrong with management practices, it can occur where conditions are excellent. Some producers dock tails at 2 or 3 days of age.
Management practices should be checked and corrected if an outbreak of tail biting occurs. In some cases, one hog of a vicious nature may initiate tail biting. If possible, the hog should be removed from the pen and placed in a separate or stronger pen.

Regrouping Hogs
It is normally impossible to market all hogs from a pen at one time. Lighter hogs from one pen can be regrouped with hogs from another pen if they are all put together in a strange pen. This procedure will tend to reduce fighting. If hogs are grouped by sex at 110 pounds, the pen will tend to empty more evenly than if sexes are mixed.

Marketing Hogs
Normally hogs should be marketed as close as possible to a carcass weight of 180 pounds. Where carcass is dressed over 180 pounds the index is automatically dropped to 91. However, hogs may be marketed at heavier weights. Hogs will dress approximately 78%. A live hog weighing 225 pounds should dress at approximately 176 pounds.
Housing for Swine
We have looked very briefly at the general principles of breeding and selection. In this section we shall consider in a general way, some aspects of housing for swine production.
The pig, like most other farm animals strives best when provided with comfortable housing conditions. Under local conditions our principal aims should be low-cost and efficiency. It .must be remember that the standard of housing may have a considerable influence on the profitability of the enterprise but this in no way means that elaborate housing could substitute for good management.

1.     Planning
Housing must be geared to the system of management to be practiced. It is absolutely essential therefore, that the prospective pig farmer has clear in his mind (preferably on paper} the type of operation he wishes to undertake.
The very first step, after consideration is given to the type of operation, is the selection of a site. The criteria are as follows:
i.          Accessibility of the area, i.e. ability to move supplies, feed and stock readily to and from the farm;
ii.         Availability of water and electricity;
iii.        Suitability for the layout and construction of the buildings;
iv.        Manure handling and disposal;
v.         Feed handling and marketing of pigs.
It is useful to visit as many units as possible to observe management of stock under existing conditions. Information on designs and costs should also be studied before making any actual expenditure.
  1. Costs
The cost of buildings will be considerably influenced by the system to be adopted. In this connection, two systems are open for consideration:
(a) Completely Indoor or Total Confinement
(b) Semi-outdoors or Partial Confinement with access to pasture.
Whatever the system selected, buildings may be designed to last for as long as 20 or 25 years. Innovations in management systems together with rapid scientific advances require that buildings should be depreciated over an eight year period. It must also be remembered that costs should include site preparation, the provision of services eq. water, electricity, roads as well as the actual estimated cost of construction.
 Types of Housing
The type and scale of operation would be the principal factors determining the specific housing to be provided. Special consideration should be given to the fo11owing:
(a} Farrowing
(b) Rearing
(c} Weaning and growing
(d} Finishing

(a)        Farrowing stalls
Farrowing stalls are essentially stalls which have been modified for operations associated with the birth of baby pigs. .The modifications entail provision of an individual crate for the sow which provides the optimum space requirement for sleeping, feeding and watering. Generally, the space is about 22 to 26 inches wide and 7 to 8 feet long. In addition, allocation of space for separate creep areas is provided such that while the piglets have access to the sow for nursing, the sow in turn is denied access to these areas. Recommended space for an average litter (about 10 piglets) is 18 inches wide, on each side of the farrowing crate. The length will of course be the same as that provided for the sow.
Many modifications to these basic requirements are possible. Among them are features such as moveable sides for the sow’s crate. This facilitates adaptation of the stall for rearing following weaning.

(b)        Rearing or Growing Stalls
 As previously mentioned farrowing stalls may be adapted to rearing by having movable sides for the crates. This would permit the entire litter to be reared for the entire growing phase (up to about 110 lbs. live-weight) in the original stall. However in the case of a producer who is not involved in breeding. Rearing pens may be designed to accommodate 30 to 40 uniform weaners.
In such a case, he would allow 4 sq. ft. for each individual until it attains 110 lbs. live-weight. Therefore the requirement will increase to about 8 sq. ft. per individual at 200 lbs. live-weight. A convenient pen size is one that measures 8 ft. wide and 16 ft. long. Thirty two weaners could be reared up to 110 lb live weight. Therefore the number is reduced to sixteen.

(c)        Finishing Stalls
 Finishing Stalls are very similar in design to the growing stalls. As suggested earlier if stalls are 16' X 8' then about sixteen animals could be finished in this area. The most important aspect about finishing stalls which should be borne in mind is that adequate trough space is provided. It is recommended that each individual must have a minimum of 20 inches of trough space when animals are dry fed.
Design may vary such that one extreme, each of these operations is treated as a specialized unit. Farrowing and rearing are usually combined in one unit and post-weaning and finishing in another. .
Because the final structure can have a high cost, attention should be paid to the occupancy rate of individual pens. For this reason a schedule of operation is absolutely essential. In doing so a minimum two-week rest period between successive uses of a pen is recommended and should be included in the schedule of operations. This simple routine facilitates disease control because individual stalls could be disinfected or limed and during the period. Housing facilities for sows and boars are equally important. The provision of adequate floor space, feeding trough space and dry sleeping areas, preferably away from their water supply are primary considerations for the comfort and well being of all stock.
At one extreme, a simple shed to provide shelter from the weather with dry bedding and access to pastures constitute a minimal requirement. In contrast, individual stalls with individual feeders and waterers together with automatic manure disposal units constitute a more elaborate alternative. Both systems as well as a number of intermediary systems have been used with varying degrees of success.

Spacing Requirements
Design and layout will influence the allocation or space. Recommendations may be varied for specific systems of management. Presented below are some guidelines for the space requirement of the various classes of stock;

TYPE OF SYSTEM                                                   RECOMMENDATIONS      
(i)         Full confinement on solid                               4 sq. ft from weaning up to 110 lb. and
            slatted or partially slatted floors                     8 sq. ft.110- 200 lbs. for each individual
(ii)        Individual Stalls –                                           dry sows 2 ft. 2 inc. x 7 ft.
(iii)       Farrowing Stalls                                              2 ft. x 7 -8 ft. and two creep areas (one
on each side) 1 ½ ft x 7 - 8 ft.
(iv)       Community Pens                                            20 – 35 sq. ft. per individual in groups of
6 – 10 sow with 20 inches though trough space/ sow.

5.         Handling of Materials
(a) Specialized equipment for handling, storage and distribution may, be justified only where it represents the most economical method of performing these tasks. Work routines for labour should be such as to facilitate the most efficient use of labour.
An important provision to be made in the planning of a swine unit is for feed storage. The following considerations must be taken into account:
(i)         Location of feed storage room – it must be easily accessible to the feed delivery truck and at the same time convenient for labour in the distribution of feed to animal.
(ii)        Size of storage room -it must be sufficiently large to accommodate the anticipated maximum feed requirements. The maximum feed requirement is calculated on the basis of the total feed consumed between deliveries together with a two week reserve.
(iii)       Protection from Pests, etc. while the feed room must be secure and provision must be made for air circulation, protection from rats and other pests must be provided. Mesh wire can be used for this purpose and wooden pallets can be used to keep feed bags away from floor level.

(b)        Manure and waste Disposal
The disposal of manure and other wastes should always receive careful consideration in planning a swine unit: fully mechanized and specialized equipment is available for manure and waste disposal. As obtained for feed storage and distribution equipment this expenditure can only be justified where it will result in the most economical method of accomplishing the task.
The simplest form of manure and waste disposal is the graded floor leading to a simple drain. Consideration must however be given to disposal of solids and the outlets for such drains. Where adequate provision is not made the area could soon become clogged and a nuisance and health hazard quickly develops.
Another very useful method by which provision is made for waste disposal is the slatted floor design. This design in its simplest form can be raised wooden slatted platform placed about 12 -18 ft above a graded floor. It may be more elaborate with slats over a disposal canal. Mechanism, solids are scraped into a slump while the liquid drains into a tank; alternatively slats may be movable to facilitate manual cleaning.

Sanitation and Disease Protection
Diagnoses and treatment of diseases require specialized training, knowledge and experience and therefore in all suspected cases of diseases, a Veterinarian should be consulted. It is however useful to point out that preventive measures may be undertaken to protect animals from diseases. As previously pointed out sound sanitation practices are the best insurance against disease problems. In spite of the effort of the farmer, from time to time some problems may arise. A few of these are described and some indications given as to preventive measures which may be taken.

(i)      Scours
'This is usually caused by bacterial infection in the stomach and is more commonly observed in young piglets prior to weaning. Indications of the infection are diarrhoea, vomiting and a rise in body temperature. Usually treated with a proprietary antibiotic will clean up the condition in a few days. However, it should be noted that there are various forms of the infection and it is advisable that al Veterinarian be consulted to avoid excessive loss. Good sanitation practices e.g. clean pens and better bedding -free from moisture; adequate fly control will go a long way into preventing an outbreak of the disease the disease. Attention to water supply to avoid contamination is also very helpful.
(ii)        Piglets Anaemia
As the name suggests, this is a disease of piglets. Piglets kept in confinement on concrete will generally suffer from iron deficiency. This deficiency results in the condition referred to as piglet anaemia. This condition may be prevented by the administration of iron either in an injectable form or sometimes orally.

(iii)       Hog Cholera or Swine Erysipelas
This is an acute highly infectious disease of swine. It comes on suddenly and pigs will develop a high body temperature in a short time. The disease is caused by a virus and because it is one of the most serious diseases of swine, all pigs should be vaccinated against this disease. This is a notifiable disease and the Veterinary Officer or Extension Officer must be contacted if the disease suspected.

(iv)  Swine Erysipelas
Generally, this disease is not very common in Trinidad and Tobago. It can however appear from time to time. It can appear in different forms but often it can show up as diamond shaped skin blotched accompanied by high body temperatures.
Vaccination of all pigs over 8 weeks of age provides protection from this disease. Again sound sanitation practices together with severe culling of carrier animals offers some measure of protection from this disease.

Slaughter Method
Preparation of Animals for Slaughter


Pigs are usually slaughtered after 4-7 months. Pigs intended for pork are usually slaughtered 1-2 months younger than pigs for bacon. The pigs are transported with trucks that have compartments with an individual capacity of 12-15 pigs. On arrival, they are unloaded and driven in lairage pens having a capacity equivalent to a truck compartment. The pigs are held there for 24 hours to recover from fatigue and stress; and they are provided with enough water to flush out intestinal pathogenic bacteria. Moreover, health inspections can be held during that holding period. The live animals are weighed prior to processing so that yield can be accurately determined.
Under ideal conditions animals should be kept for some while before slaughter (soft bedding).
Factors Affecting Ideal Conditions
1. Climate conditions (extremes of temperature and humidity)
2. Condition of animal (age, health, sex etc.)
3. Distance travelled
4. Method of transport (how animal is restrained in transit)
Time necessary under ideal conditions for pigs 12- 24 hours; under extreme conditions may be as long as three days, cattle and sheep 12 -14 hours, lack of food but presence of water is not necessarily stressful.
The Effect on Animal Condition
Poor Bleeding
If the heart stops pumping; very little blood comes out (if the animal is easily stressed stunning can kill it) supermarket meat should contains no blood, blood is a very good medium for bacterial growth, therefore blood decreases keeping time.
If animal is fatigued it may use all its glycogen before death therefore no lactate is formed after death pH therefore does not drop, pH determines the ease with which bacteria can proliferate in meat a high pH quick spoilage also, there is a dark colour, meat also loses its normal juiciness.
But cells cover themselves with a protective layer of skin. Under stressful condition bacteria can move across gut wall into blood stream and then on to meat.

Three Methods of Stunning
1. Mechanical -concussion i.e. Use of captive bolt gun, pole axe, knocking hammer.
2. Chemical -asphyxiation -Use of carbon dioxide gas
3. Electrocution -Use of an electric probe apply to the head from one to four seconds 
    depending upon the weight of the hog.
Before slaughtering, pigs undergo electrical or carbon dioxide stunning. In the first case, they are stunned using high frequency (50 Hz), low voltage electric current applied by means of two electrodes, which are placed on either side of the brine using tongs. The current induces a state of immediate epilepsy in the brain during which time the animal is unconscious. In the later case, the pigs are passed through a well with a CO2 and air atmosphere. Legally a minimum of a 70 % concentration of CO2 by volume is required, but a 90 % concentration is recommended. The pigs are again rendered unconscious due to the acidification of the cerebrospinal fluid upon inhalation of the CO2. With the CO2 method “blood splashing” is eliminated, and it also removes the human element required in the electrical stunning.
During their state of unconsciousness, the pigs are hoisted onto an overhead rail for slaughtering.

Sticking & bleeding

In a state of surgical anesthesia, the pigs are shackled and hoisted for exsanguinations. The stunned animals undergo exsanguinations (sticking) with blood collected through a special floor drain or collected in large funneled vats or barrels and sent to a rendering facility for further processing.
The carotid artery and jugular vein are cut to drain out blood and to get the muscles relaxed for easy dehairing. Pigs should be allowed to bleed for about 5 minutes.
A five to seven seconds interval between stunning and sticking is advisable.
The advantage of any of the above methods, aside from the human factor are the elimination of excitement fewer internal ham bruises, safer and better working conditions, more economical operation and an improved product.

Scalding, Scraping/ dehairing  and Eviscerating
A safe scalding temperature is 150 -160°F but water up to 180°F can be used if the operator removes the hog as soon as the hair slips easily.
A bell-type scraper that is fairly sharp is an important factor in the effective removal of the scurf or hair.  
Pig carcasses are not skinned after exsanguinations (bleeding). Instead, the carcasses are dropped into scalding water which loosens the hair for subsequent removal. The carcasses should be kept under water and continually moved and turned for uniform scalding. In large plants, carcasses enter the scalding tub and are carried through the tub by a conveyer moving at the proper speed to allow the proper scalding time. During the hard-hair season (September-November), the water temperature should be 59° to 60°C and the immersion period 4 to 4,5 minutes, while in the easy-hair season (February-March), a temperature of 58°C for 4 minutes is preferable. In small plants without automation, hair condition is checked periodically during the scalding period. The dehairing process is begun with a dehairing machine, which uses one or more cylinders with metal tipped rubber beaters to scour the outside of the carcasses. Hot water (60°C) is sprayed on the carcasses as they pass through the dehairer moving toward the discharge end. The carcasses are removed from this machine, hand scraped, then hoisted again, hind quarters up. The carcasses are hand-scraped again from the top (hind quarters) down. Any remaining hairs can be removed by singeing with a propane or similar torch. Once the remaining hairs have been singed, the carcasses are scraped a final time and washed thoroughly from the hind feet to the head. Some plants pass the carcasses through a singeing through gas flames.

Splitting the Pelvis
The cut is made mid-way between the two hams, following the white tissue leads to the fusion point of the pelvis which is cartilaginous in nature. Take a good grip on the knife and give a sharp thrust towards the backbone. The hand will prevent the knife from cutting the bung gut.


After scalding and dehairing, singeing, or skinning, the head is severed from the backbone at the atlas joint, and the cut is continued through the windpipe and esophagus. The head is inspected, the tongue is dropped, and the head is removed from the carcass. The head is cleaned, washed, and an inspection stamp is applied. Following heading, the carcass is eviscerated. The hams are separated, the sternum is split, the ventral side is opened down the entire length of the carcass, and the abdominal organs are removed. These viscera are received in a moving gut pan to segregate edible (heart, liver) and non edible offal. Intestines are cleaned for sausage casings. The thoracic organs are then freed. Non edible offal is discarded into a barrel to be shipped to the rendering plant.


The carcass is cut into two halves.
Washing: The carcass is then washed from the top down to remove any bone dust, blood, or bacterial contamination. A mild salt solution (0.1 M KCl) weakens bacterial attachment to the carcass and makes the bacteria more susceptible to the sanitization procedure, especially if the sanitizing solution is applied promptly. Dilute organic acids (2 percent lactic acid and 3 percent acetic acid) are good sanitizers. In large operations, carcass washing is automated. As the carcass passes through booths on the slaughter line, the proper solutions are applied at the most effective pressure.


Cutting and deboning are easier to carry out at lower temperature. Therefore, the carcasses are transferred to chill tunnels and chill rooms to cool them down to 0-1°C with air velocity typically 5 to 15 mph, equating to –5°C wind chill, for a 24-hour chill period. For thorough chilling, the inside temperature of the ham should reach at least 3°C. With accelerated (hot) processing, the carcass may be held (tempered) at an intermediate temperature of 16°C for several hours, or be boned immediately. When large numbers of warm carcasses are handled, the chill room is normally pre-cooled to a temperature several degrees below freezing –3°C, bringing the wind chill to –9°C to compensate for the heat from the carcasses

Cutting into smaller pieces

The carcasses are processed into 5 primal cuts of meat (Picnic shoulder, Boston But, Ham, Loin & Side). During further cutting into smaller pieces, the slaughters are assisted in their work by automated transport trays and conveyors. They help in cutting and sorting meat and bone. The products are finally efficiently packaged and stored at low temperature prior to further processing.   

As in beef, economically important carcass and live traits are considered in swine and are as follows:(1) live weight; (2) dressing percent; (3) fatness; (4) carcass length; (5) muscling; (6) USDA grade;  (7) percent muscle.
Live Weight – Market hogs do not vary in live weight as much as beef cattle and can be subjectively estimated with more accuracy.
                Normal Range:  190 – 270 lbs.
                Average:   245 lbs.
Dressing Percent – Dressing percent is highest of the three meat animal species. Due to the fact that pigs are only monogastrics. Dressing percent of market hogs with adequate condition should grade choice.
                Normal Range:  68 – 77%
                Average:   72%
Fat Depth – Last rib fat depth is measured at the last rib, and is the primary factor in determining carcass grade. Tenth rib fat is measured between the 10th and the 11th and is also used in calculating percent muscle.
Muscling – The degree of muscling of a hog is considered when grading market hogs and pork carcasses. Three degrees of pork carcass muscling are recognized in the pork grading standards.
                Muscle Score #1 – Thin (Inferior)
                Muscle Score #2 – Average
                Muscle Score #3 – Thick (Superior)
Loin eye area is also another estimate of carcass muscle and is used in the percent muscle equation. Loin eye area is measured between the 10th and 11th ribs on pork carcasses and is highly correlated to carcass muscle.
                Normal Range:  3.5 – 7.0 in2
                Average:   4.8 in2
USDA Grade – USDA Grade is determined based on quality indicating characteristics of the lean and expected yield of the four lean cuts (ham, loin, picnic shoulder and Boston butt). The following equation is used to estimate the grade of barrow or gilt carcasses.
USDA Grade = (4.0 x Last Rib Back-fat Thickness, in.) – 1.0 x muscle score)
The muscle scores in this equation are: thin = 1.0; average = 2.0; and thick = 3.0. Exceptions to this equations are that carcasses with thin muscling cannot grade U.S. No. 1 regardless of last rib fat depth (LRFD) and carcasses with 1.75 in. or more of LRFD cannot be graded as U.S. No. 3 regardless of muscling.
Examples of USDA Quality Grades
Percent Muscle – A more accurate and precise method of assessing differences in carcass yield of lean red meat. The factors used to predict percent muscle include hot carcass weight (HCW), loin eye area (LEA), and tenth rib fat depth (10RFD). The following is an equation used to estimate pounds of muscle containing 5% fat:
   Lb. of muscle containing 5% fat = 7.231 + (.437 x HCW) + (3.877 + LEA) – (18.746 x 10RFT)
Percent muscle can then be calculated as follows:
        % muscle = Pounds of muscle x 100
                           Hot carcass weight

Friday 24 November 2006

castrated male swine
uncastrated male swine
Boar effect
boar exposure to gilts causes earlier onset of puberty with some synchronization
Boar power
boar use efficiency
Breeding Herd
includes boars and females in stages of gestation, breeding, and farrowing
Breeding Soundness Evaluation (male)
assessment of libido, mating ability, and capacity to produce and ejaculate normal semen
Bulbo-urethral glands
located at ischiatic arch under penile crura and secrete the tick gel portion of the ejaculate
Bacteroides succinogenes  & Ruminococcus flavefaciens: 2 bacterias found in intestines of sows that are capable of breaking down fiber
10 to 20cm long with transverse folds which are continuous with the vaginal mucous membrane. Transverse folds form a "corkscrew."
Continuous farrowing
sows (and gilts) grouped in weekly batches, use all in/all out, practiced by larger operations (see periodic farrowing)

Ductus deferens
lacks an ampulla, empties directly into pelvic urethra at seminal colliculus; microscopically, glandular tissue is present in ampullary area
difficulty giving birth

tail: dorsal/ head: ventral/ body: cranial + medial making it difficult to palpate due to location
readiness to mate
Evaporative cooling
cooling of the body by loss of the heat required to convert water liquid to vapor

Farrowing or Feeder pig operation
most intensive breeding system; producer has no grow/finish floor and sells feeder pigs
Feeder pig operation
breeder sells his grower pigs to a finishing operation to grow them out to market weight
Finishing operation
buys feeder pigs and feeds them to 240 to 250 lbs
increasing energy intake 10 to 14 days prior to estrus to increase number of ova ovulated
practice of placing piglets from dams with too many piglets to feed adequately to mothers with extra udder space, should occur in first few days after birth
young female swine, up to and including primiparous (1st litter) females; about 6 months old and 200 to 220lbs
Grower pig
pig being grown out to market weight, usually takes about 16 weeks

Hand mating
boar is brought to individual female for servicing
generic term, usually applied to growing swine

Female's external lips of the vulva, characteristically become hyperaemic(engorged with blood) and swollen at estrus (or under the influence of exogenous estrogen.)
Limit Feeding
Feeding strategy in which pigs are fed a specific amount of food in a time period. Contrast with free-feeding for a specific time period.
Market weight
240 to 250 lbs
breeding a sow or gilt after the onset of estrus and before ovulation, may include repeated servicings and servicings by multiple boars and still be considered one mating
Meat breeds
used in boar lines in cross-breeding schemes; include: Hampshire, Duroc, Poland China, and Pietrain (pronounced Peé-a-trin)
Mother Breeds
used in maternal lines in cross-breeding schemes; include: Yorkshire, English Large White, Landrace, and Chester White

Non-productive Sow Days
days a sow is not lactating or gestating

oval shape, mulberry-like appearance due to the multiple follicles/CL's present

giving birth; specific term for swine is "farrowing"
Pen mating
boar is placed with group of sows for servicing (see hand mating and AI)
fibro-elastic with no glans penis; the distal 5-6cm has a counter-clockwise coil which "locks" into the cervix of the female; the urethral orifice is a small slit 1 cm from the distal end of the penis; the sigmoid flexure is located cranial to the scrotum
Periodic farrowing
twice per year farrowing practiced by smaller operations (see continuous farrowing)
generic term, usually applied to immature swine
Pig constipation
pig production exceeds the capabilities of the facility
Pork producer
integrated swine producer and meat packer
a dorsal prepucial diverticulum is present; has been incriminated in infectious processes (but without proof)
disseminate portion surrounds urethra, the body lies ventral to the vesicular glands
time at which first estrus occurs in females, usually at 6 months of age, but depends on breed, environment and season of the year. Puberty is more gradual in boars progressing over 5 to 18 months of age from onset to full maturity.

Segregated early weaning
SEW, removal of pigs from mother at 10 to 4 days of age in order to facilitate disease management
deposition of semen into the cervix of a sow or gilt. may be by "natural" boar or artificial insemination
archaic term, usually applied to growing swine
adult female swine
Standing Heat
when a sow or gilt is ready to be bred, she will assume a rigid stance and maintain it throughout the servicing

heritable trait; the number and spacing of teats on boar and sow are important
large and symmetrical; orientation is long axis vertical/oblique

The uterine horns are short and convoluted when non-pregnant and up to 1.8 m (6ft) in length during pregnancy. The uterine body is short, about 5cm long.

The degree of cornification of the epithelium changes with the cycle and pregnancy status, but it is not as dramatic as in the bitch, and thus not reliable for determining stage of cycle.
Vesicular glands
large,paired lobulated glands that occupy the major portion of the pelvic inlet and empty into the pelvic urethra at seminal colliculus

Weaner pig
from weaning up to about 40 lbs


       1. Cunningham, Acker Animal Science and Industry, 6th edition
2.  Bundy, Clarence E and Ronald V. Diggins. 1970. Swine production, 3rd Edition,    
      Prentice –Hall, Inc., Englewood Cliffs – New Jersey.
3.   Bunn, A.J., 1972-1974- Ontario
      Fact sheet Order No.   72-046, 74-063, 72-045, 74-034, 74-069
4.   Jamaica Livestock Association Limited, 1983, Livestock Manual for the tropics. J.L.A. – Jamaica.
5. Boggs D. L & Merkel R .A 1993. Live Animal Carcass Evaluation and selection 
6.   Damron W. Stephen: An Introduction to Animal Science, Gobal, Biological Social & Industry Perspective.
7.   Hafez E.S E. Reproduction in Farm Animals
8.   MERCKS & CO .INC. The Mercks Veterinary Manual.
9.   Muchette,   A. J. Pig Production
10. Taylor. R.E. Thomas. G. F. Scientific Farm Animal Production.


Methods to reduce PSE and bloodsplash

Observations by the author at slaughter plants and farms all over the United States, Canada, Europe, and Australia indicate that producers are responsible for about 50% of the pale, soft, and exudative (PSE) pork on the market, and packers are responsible for the other 50%. Surveys conducted in slaughter plants in two different countries indicated that PSE levels varied over 100% between different producers.
Genetics is probably the single most important factor contributing to the prevalence of PSE pork today. Some pork-grading systems motivate producers to breed pigs that carry the stress gene. These animals have maximum lean and weight gain (Aalhus et al .,1991). Unfortunately, they also have high levels of PSE. Some of the highest levels of PSE were recorded in hybrid pigs, which had been selected for leanness and rapid growth. The breeding companies have recognized the problem and have taken steps to produce lines that will have lower levels of PSE. DNA testing methods will enable the PSS (porcine stress syndrome) gene to be eliminated (Sellers, 1993).
At one plant, a certain line of commercially available hybrid pigs constituted 10% of the pigs received each day. Ninety percent of the pigs that were dead on arrival or died in the yards came from these hybrids. Genetics has a large effect on death losses (Murray et al., 1998). Genetics is not the sole explanation for differences between producers. A survey conducted at a vertically integrated operation indicated that PSE levels varied 5-10 percentage points among producers who raised identical pigs in identical buildings. Handling, management, and transport also had an effect. Several surveys have shown that pigs transported a short distance will have more PSE compared to pigs transported a longer distance. Observations by the author have indicated that pigs hauled very short distances for under 30 minutes are often more stubborn and difficult to drive at the plant compared to pigs hauled longer distances (Grandin, 1993a). Pigs hauled long distances are more likely to have DFD (dark firm dry) meat because glycogen stores become depleted.
PSE can be reduced by fasting pigs 12 to 24 hours prior to slaughter (Warris and Bevis, 1987; Eikelenboom et al.,1990). Pigs should have access to water at all times. To reduce the possibility of carcass weight loss, a shorter fasting period of 12 hours prior to stunning and slaughter is recommended (Grandin, 1993).

Excitable pigs
There are problems with excitable pigs. The leanest animals with large muscles often have the worst excitability problems. Shea-Moore (1998) found that high lean pigs were more fearful. These pigs often have the worst meat quality problems. Pork from stress gene pigs which are grown to heavy weights is tougher and drier than pork from pigs which are stress gene free (Monin et al., 1999). Excitable pigs are very difficult to handle at the slaughter plant. This creates both meat quality and welfare problems. Handling excitable pigs at 1000 per hour in a single file race is difficult to do quietly. Some plants have installed two stunners to improve handling. Fortunately some of the vertically integrated companies have removed the stress gene from their herds. This has resulted in calmer pigs which are easier to handle. They are now breeding pigs for quality instead of quantity.
Handling of pigs can also be improved by installing a system which eliminates the single file races. The Danes have developed a CO2 stunning system where pigs are stunned in groups. Cattle move very easily through a single file race because their natural behavior while walking from pasture to pasture is to move in single file. Pigs do not have the instinct to walk in single file. When pig excitability increased, problems with single file races increased. When pig excitability is reduced single file races will have fewer problems.
Many excitable pigs are animals that have been raised in confinement (Grandin, 1993). Genetics is a major factor. Observations by the author in identical pig confinement buildings and in the same slaughter plant indicated that changing genetics improved handling. Pigs with a calmer temperament were easier to handle and PSE was reduced. There is a definite need for breeding companies to select pigs for temperament. This is especially important for pigs raised in confinement.
In confinement buildings, producers must provide pigs with more environmental stimulation. Providing confinement pigs with additional environmental enrichment, such as toys and people entering the pens, produced calmer pigs that were easier to drive (Grandin,1989; Pederen,1993). Producers need to eliminate practices such as keeping pigs in darkened rooms. Playing a radio in the building can help get pigs accustomed to sounds. Pigs that have been finished in a pen with a radio playing at a reasonable volume are less likely to be startled by sudden noises.
Producers should walk in the finishing pens every day to get the pigs accustomed to handling. The person should quielty walk through each pen in a different random direction each day to teach the pigs to quietly flow around them. The person should not stand in the pen and allow pigs to chew on their clothes. This trains the pigs to approach and chew instead of driving. Geverink et al (1998) reported that confinement pigs which have been driven in the aisle during finishing were easier to handle. Moving pigs out of their finishing pen one month prior to slaughter improved their willingness to move (Abbott et al., 1997)
Observations by the author have also indicated that raising finishing pigs on plastic or metal floors produces animals that are hard to drive because they do not know how to walk on concrete. Plastic or metal floors work well for young pigs, but during the final finishing phase, confinement pigs should be raised on a concrete surface. Producers must also avoid producing pigs with a high incidence of either hernias or spraddle legs. Both of these conditions have a strong genetic component.
Slaughter plant factors
After pigs arrive at the plant, handling and chilling practices will have a large effect on the incidence of PSE. I estimate that handling practices account for 10%-15% of the variation in PSE, and chilling practices account 20%-40%.
Improvements in handling practices have enabled several plants to ship 10% more pork to Japan. These handling procedures will reduce PSE:
  • Schedule trucks to prevent delays during unloading. Heat builds up rapidly in a stationary truck. Do not overload trucks.
  • Rest pigs for 2-4 hours prior to slaughter (Malmfors, 1982; Milligan et al., 1996). Trucks must be scheduled to allow adequate resting time.
  • Shower with cool water during hot weather (Smulders et al.,1983).
  • Handle gently in the stunning chute. Rough handling during the last 5 minutes prior to slaughter increases PSE, because pigs become overheated. Handlers must be taught behavioral principles of pig handling. Over-exertion and excitement shortly prior to stunning increases PSE in stress-resistant pigs that do not have the stress gene (Sayre, 1963; Barton-Gade, 1985).
  • Reduce or eliminate electric prods in the stunning area. Stressful handling shortly before slaughter will damage meat quality (Warriss et al., 1990; D'Souza et al., 1998; Van der Wal, 1997).
  • Reduced squealing in the stunning area will help reduce both PSE and bloodsplash. Squealing is associated with increased stress and lower meat quality (Warriss et al, 1994). The last five to ten minutes prior to stunning is most critical for reducing PSE.
  • Fill the crowd (forcing) pen which leads up to the single file race only half full. Move small groups fo pigs. In group stunning systems the staging areas that leads into the stunning areas should be filled half full. Pigs need room to turn.
  • Replace electric prods with other driving aids such as flags, panels, or paddles.
  • Eliminate distractions which make pigs balk and refuse to move such as air drafts blowing in their faces, sparkling reflections on the floor, shadows or small moving objects such as chains. If pigs constantly back up, the distraction that is scaring them must be removed (Grandin, 2000, 1996). 
Lower temperature
Gentle handling, rest, and showering helps lower body temperature. Pigs that are overheated are more likely to have PSE or DFD meat (Gariepy, 1989). Heat damages the meat, both in live pigs and shortly after slaughter, making proper chilling important. Sometimes carcasses are jammed together or there is insufficient refrigeration. Some managers make the mistake of maximizing pig numbers by overloading the cooler. They are saving a few pennies on numbers and throwing dollar bills away in carcass shrink losses. It is easier to quantify pigs per hour and person hours than shrink loss and customer dissatisfaction. The industry needs to change its mind set and eliminate the "ram and jam" mentality. To succeed in the marketplace of tomorrow, quality must come first and quantity second.
Segmented market
A segmented market causes losses to be passed from the producer to the next person in the marketing chain. A producer who sells pigs live-weight has no motivation to improve quality. Live-weight selling or a carcass marketing system that fails to reward quality are the major causes of quality problems. The producer gets the wrong economic incentives. Some grading systems reward lean, highly muscled pigs with high levels of PSE. The electronic probes currently being used by the packing plants measure fat thickness and the size of the loin, but there is no PSE measurement. This motivates the producer to select breeding stock for rapid gain, leanness, and muscle growth. These selection pressures have resulted in high levels of PSE because pigs carrying the stress gene are kept as breeding stock. The swine industry needs to use an accurate method for measuring PSE so that a PSE measurement can be added to the fat and loin eye size measurements. The producer must be financially rewarded for producing lean pigs with low levels of PSE. Changing the carcass measurement and payment system to include PSE measurement will motivate producers to reduce the incidence of the stress gene in their herds. The bottom line is that the producer has to be financially rewarded for producing quality pork instead of maximum tonnage.
Bloodsplash is damage to the meat caused by either small pinpoint haemorrhages or large blood clots in the meat. It is a severe cosmetic defect that affects the appearance of the meat. Haemorrhage problems are mainly caused by problems inside the plant, but nutritional factors such as low levels of selenium and vitamin E may possibly contribute to it by weakening capillary walls. Lean pigs often have more problems with bloodsplash.
These procedures have effectively reduced bloodsplash in many plants which use electric stunning:
  • For electric stunning, use an amperage power supply where the amperage remains constant and voltage varies with pig resistance. Old fashioned voltage-regulated stunners allow amperage spikes that damage the meat. Some plants have built their own electronic constant amperage power supplies. These units can lower bloodsplash over 100%. To ensure good animal welfare, a minimum of 1.25 amps must be used to reliably induce a grand mal seizure and produce instantaneous unconsciousness (Hoenderken, 1983). For large market pigs, a minimum of 300 volts should be used and slightly lower voltages can be used for lighter market pigs (Hoenderken, 1983; Gregory, 1988). Some plants have attempted to reduce bloodsplash by reducing amperage to 0.5 amps. This must never be permitted because scientific research has shown that low amperages or frequencies over 800 Hz fail to induce instantaneous unconsciousness.
  • Bleeding a pig within 10 seconds after stunning will reduce bloodsplash. Prone sticking systems accomplish this, but older, hanging sticking systems sometimes have intervals of over 30 seconds. Quick bleeding also improves animal welfare because it reduces the possibility of an animal reviving (Hoenderken, 1983; Blackmore and Newhook, 1981).
  • The operator must be careful to avoid double stunning and causing the pig to contract more than once (Grandin, 1985/86). Double stunning can be caused by allowing the stunning applicator to slide during the stun or turning on the electricity before the applicator is pressed firmly against the pig. The pig should not squeal when the stunner is applied.
  • Worn cords and switches should be replaced. Slight disruptions in electrical continuity will cause bloodsplash. Wet cords can also cause problems.
  • Reduce electric prod usage. In a research trial, elimination of electric prods reduced bloodsplash (Calkins et al.,1980).
  • CO2 stunning will reduce bloodsplash (Velarde et al., 1999). The disadvantage is that it is expensive to operate and it requires well trained maintenance technicians.
Other Factors
Both PSE and bloodsplash will fluctuate with weather changes. Observations by the author indicate that PSE levels may double during the first 4 hot days of spring. Bloodsplash tends to worsen when temperatures fluctuate. It is very important to take weather into account when new methods for reducing PSE or bloodsplash are being tested. In one study, the amount of bloodsplash reduction benefit provided by new handling and stunning procedures greatly fluctuated, depending on the weather (Grandin, 1988). On some days, it provided great reductions in bloodsplash and on other days, almost no reduction. The procedures must be tested over a period of weeks to eliminate confounding effects of weather.
Bloodsplash can be reduced by the use of CO2 stunning (Velarde et al., 1999). Recent observations in a plant equipped with both state-of-the-art CO2 and constant amperage electrical stunning equipment indicated that PSE and bloodsplash levels were almost identical. CO2 definitely reduces bloodsplash compared to old-fashioned voltage regulated electrical stunning equipment. New CO2 stunning systems could provide handling advantages by eliminating the need to line pigs up in single-file chutes. However, there have been concerns about humaneness (Hoenderken, 1983). Some genetic lines of pigs react very well to CO2 and others may possibly be stressed. The Yorkshire breed reacts very well (Forslid, 1987), but stress-susceptible pigs may possibly be conscious during the initial excitation phase (Troeger and Waltersdorf, 1991). Therefore, CO2 may be an excellent method in a vertically integrated system where pig genetics could be controlled, but animal welfare may be poor for certain genetic types of pigs.
The biggest problem facing some segments of the industry is the emphasis on quantity rather than quality. Producers need to be provided with a marketing system that provides economic incentives to improve pork quality rather than just grow heavier pigs. In the 90's the "mind set" of a large segment of the United States pork industry was commodity based. The entire mind set of the industry needs to change from commodity-based to consumer-based. When this occurs, new procedures will be developed quickly. Fortunately, the industry has become more quality oriented and this has resulted in improvements in pig handling and changes in genetics.
Until this happens, nobody will be motivated to invest the time or the money to change systems.