A recent review has shown that leukocytes in colostrum have a major role in immunity in calves. It has long been known that immunoglobulins (antibodies) in colostrum pass on immediate protection, but this communication talks about the latest evidence that leukocytes (white blood cells) from the mother’s colostrum are ingested in the first feed. They pass into the gut of the calf within 12-24 hours and appear in the circulation. They then disappear from circulation within 36 hours. This implies that they are actively migrating to, or interacting with the immune system of the calf (reference of Reber, 2006). Monocytes migrate to lymph nodes in order to pass on information to the long-term, acquired immune system and this may help to strengthen the calf’s immune health.
This review from Mike van Amburgh at Cornell University, looks at papers supporting the theory that maternal cells play an important role in the “memory” of the calf’s immune system. It goes on to look at the effect of amounts and freezing of colostrum and its impact on the immune health of the calf.