As promised, here’s a selection and breeding programme that can be used on a small-scale farm with 20 or fewer breeding sows.
Selection: A healthy boar should weigh 90kg before he is 140 days old. To grow from 30kg to 90kg, he will require a maximum of 3kg of feed to gain 1kg in weight. Buy boars at least four weeks before putting them to the sows for the first time. This will allow you to keep them in quarantine and give the boars a chance to adapt to their new environment.
Training: Make sure the young boars don’t hurt themselves or the sows when serving for the first time. The boar must be at least eight months old, and he and the sow should be about the same size. A small sow and not a gilt (young female) should be used to ‘train’ the boar. The boar should serve the sow in his own pen. Make sure the floor is not slippery and that all obstructions are removed.
How to train the boar:
Stand in the pen with a large piece of hardboard or something similar to separate the animals if they harass each other. Don’t hurry the boar; let him work at his own speed. If need be, direct him gently to the rear of the sow. Be patient with both animals. If the sow is on heat, she won’t move around the pen too much. Help the boar by allowing the sow to stand with her head towards the corner of the pen.
After service, allow the boar to spend a few minutes nuzzling the sow, but do not allow him to remount. If a young boar doesn’t serve the sow the first time, repeat these steps every two to three days if possible. A young boar should not be used more than twice a week until he is one year old. Older boars can be used three times a week, but preferably not on consecutive days.
If you have about 20 breeding sows, keep at least two boars – a young boar to serve gilts that come on heat for the first time, and a mature boar to serve older and heavier sows. It’s also advisable to have a spare boar available, if possible.
Finally, keep a record of the dates when the boar has served a sow, as well as the number of the sow that has been served. In this way, you can identify and cull infertile boars and boars that give small litters.
Boars usually have a maximum working life of 18 to 24 months. This means they should be replaced when they are 30 to 36 months old.
The gilts should have strong, straight legs with large, even-sized claws. They must have a well-formed vulva and six well-shaped, prominent teats on each side of the belly. These should start well forward and be spaced evenly to allow adequate suckling space for the piglets.
Make sure you have enough gilts available to keep your breeding programme on track. If need be, buy extra animals – ideally from the same farm where the boars come from, as the owner can advise you on your breeding programme.
Gilts are usually selected for breeding at five to six months. Pigs not chosen can be sold as baconers at a live weight of about 90kg. Rear your breeding gilts until they weigh between 120kg and 130kg (seven-and-a-half to eight months). They are then ready to be served by a boar for the first time.
Gilts have to be in a good condition to produce large litters (eight to 10 or more healthy piglets) and should not be too fat when they’re ready for mating. To get them to the right weight, feed them about 2kg of meal per day from the time of selection until mating. This will also ensure they stay in good condition after weaning their first litter.
There are several reasons for removing sows from the herd: failure to conceive; not coming on heat; abortions; lameness; small litters; old age; and lack of milk. After removing the sows, do not try to feed them up before selling them – it does not pay. As soon as the sow’s udder has returned to normal after weaning, send her to the abattoir. A replacement gilt can then be brought into the herd immediately.
Sows that farrow regularly, rear large litters (nine or more piglets) and are free of other problems and diseases should be allowed to rear six or even more litters before culling.
Sources: Farming with Pigs (compiled by the Western Cape department of agriculture); Guide to Small-Scale Pig Farming (department of agriculture) by EH Kemm; the South African Pork Producers’ Association (www.sapork.com).