A calf is born without the necessary antibodies to resist viral and bacterial infections, which can cause high mortality rates within the first week of life. Acquired passive immunity from receiving colostrum is critical for the survival and subsequent growth of the newborn calf. We've studied colostrum in dairy cattle because in western states, 'chugging calves' has been going on for years. There is a tremendous increase in demand for milk in the early fall when school begins. For dairy farmers around the state to meet these demands, cows need to begin calving during the late summer and early fall.
Cows suffer from heat stress just as some humans do.
The cow is exhausted after laboring and then giving birth, which makes it difficult for her to stand up and allow the calf to nurse. The calf is also stressed from the difficult labor process and is often too weak to stand and nurse. Without receiving high doses of colostrum from the mother's milk, the calf doesn't receive high levels of antibodies for immunity. It has been estimated that 60 percent of calves that are allowed to nurse do not receive enough antibodies, as they are too weak at birth to vigorously nurse. Immunoglobulins found in colostrum are very large protein molecules.