Milk may be absent because it has failed to let down or because the dam is not producing milk.
Failure of Milk to Let Down
Most mothers instinctively encourage their puppies to suckle soon after delivery. Suckling stimulates the release of oxytocin from the pituitary gland. Oxytocin is responsible for milk letdown. A nervous, frightened, or stressed mother may discourage her puppies from suckling, or may release a hormone (epinephrine) that blocks the action of oxytocin.
This condition, which resembles galactostasis, should be suspected if the mammary glands are firm and swollen but no milk is found in the teat canals. Puppies who are not receiving milk should be supplemented. Between supplements, it is important to encourage suckling to continue breast stimulation. Once the milk comes down, the dam usually accepts her puppies.
Treatment: Examine all the nipples to be sure they are open, fully formed, and erect. A deformed nipple may cause difficulty in suckling. A recessed nipple can be improved by massaging it to stimulate the flow of milk and then putting a vigorous suckler directly on that nipple.
The problem can be solved by giving oxytocin. It may be necessary to repeat the oxytocin during the first 48 hours.
Failure to Produce Enough Milk
True agalactia can be suspected if the bitch’s breasts do not develop in late pregnancy. This condition may have a genetic basis. These puppies must be hand fed using artificial bitch’s milk.
Occasionally, a dam with a large litter is incapable of producing enough milk to satisfy all her puppies. The most common cause of insufficient milk production is failure to feed the mother an adequate number of calories, especially during the second and third weeks after whelping, when nursing demands are greatest. This problem is entirely preventable (see Feeding a Nursing Dam).
Treatment: There is no way to make a bitch produce more milk. If the mother is constitutionally unable to produce enough milk, her puppies should be supplemented with artificial bitch’s milk.