A healthy well-fed sow will be able to rear at least 20 piglets each year.If the sow has too many piglets to feed, or if a sow dies, the young can be fostered or hand reared.
A sow should have at least fourteen teats which should be long and thin enough for the piglet to grasp. Each piglet suckles from its own teat feeding every hour. The first born and stronger piglets use the teats nearest the sow's head which produce most milk. As a sow gets older and has more lifters the teats can become large making it difficult for the piglet to suckle. Sometimes the back teats do not produce much milk. A sow may be unable to feed all her young and is no longer fit for breeding.
A sow can suffer from mastitis which may develop as a result of damage to the teats caused by the piglet’s teeth. Clipping the teeth of the piglet prevents cuts to the teats.
Not all of the piglets will grow at the same rate, some will be born smaller than the others. They fight for feed and the smaller piglets will grow at a slower rate and even die. You can expect to see a difference in weight gain and growth between the members of any litter, but if all of the piglets do not grow well and there are no obvious signs of disease you should suspect poor milk production by the mother. This is often the case with old sows. It can become necessary to foster the piglets, i.e. put them with a different sow for feeding.
It is essential for all piglets to take colostrum from the mother. They will take the first feed within 1 hour of being born.
If a sow dies during farrowing her lifter can be fostered to another. The orphans should be mixed in with the sow's own litter so that she will accept them. However, the foster mother will not be able to feed both lifters at the same time and it will be necessary to use several foster mothers to feed the orphans.
A sow may die and there is no foster mother available. The litter can be reared by hand feeding. To hand rear a litter the following will be needed:
source : Pashu Sakhi Handbook