Nursing puppies place huge demands on their mother's body. For several weeks, she's at their constant beck and call for feeding. If the weaning process takes place gradually, that's the best outcome for both mother and offspring. She gradually produces less milk as the puppies rely more on solid foods. By the time the puppies are completely weaned, she should be "dry."
From pregnancy through weaning, feed the mother dog a high-calorie diet, allowing her to adequately nourish herself and the growing puppies. When the puppies are newborns, the first milk the mother produces is colostrum, the rich first milk packed with antibodies that confer the mother's immunity on the babies. Within 24 hours, the colostrum is replaced by the milk that will continue to nourish the litter until weaning.
When her puppies are about 3 weeks old, the mother dog's milk is at peak production. Depending on the number of puppies and the breed, the mother eats almost four times her normal amount of food, divided into several feedings. As always, she needs a constant supply of clean water, but she's likely to drink more than normal. By 4 weeks old, you start giving the puppies some solid food, so a gradual weaning process begins.
At about 4 weeks, the weaning process begins. As the puppies' teeth develop, their sucking hurts the mother; she's less inclined to let them nurse. The puppies become more independent, spending less time with Mom and more time playing and exploring their environment. By 6 weeks, weaning should be complete. You can send puppies to their new homes after the age of 8 weeks.
As the puppies nurse less, gradually reduce the mother's food. Once the pups are weaned, unless your vet tells you otherwise, mother dog resumes her pre-pregnancy feeding. If the mother continues to produce milk after weaning, discuss it with your vet. She might advise withholding food and water for 24 hours, along with applying hot compresses and massaging the area around the teats.
After the puppies are born, the mother might experience issues with her milk production or nipples. If any of her nipples become swollen or hard, causing her pain, she might have a mammary gland infection. Call your vet if your dog has any mammary issues.
Because of constant nursing demands, the mother dog could suffer from low blood calcium, which can cause a potentially fatal disease known as eclampsia, or milk fever. Symptoms include muscle twitching, excessive panting and loss of coordination. In a worst-case scenario, the mother dog experiences seizures. Stop all nursing at once and take the mother dog to an emergency veterinary hospital immediately if you see any symptoms of milk fever. You will have to feed the puppies a commercial milk replacer until either the mother dog recovers enough to resume nursing or the litter is ready for weaning. Consult your veterinarian before allowing the mother to resume nursing.