Colostrum is the most important meal a calf will ever have. Colostrum is referred to as “first milk”, but this is actually much more similar to blood than milk. Colostrum contains 22 percent solids, compared to 12 percent solids in normal whole cow’s milk. Besides being very high in immunoglobulns (Ig) for disease and infection prevention, it is a source of energy, vitamins, white blood cells and growth factors.
A calf’s immune system is not fully developed at birth. The immunity a calf attains by consuming colostrum is called passive immunity. Passive immunity is that which is received passively from an outside source; conversely. The calf must rely on colostrum from the cow until its own active immune system is totally functional (about 1 to 2 months of age). Continue reading