Analysis of the antitrypsin activity and immunoglobulin G concentration in equine colostrum and milk

Antitrypsin activity in equine colostrum is highest immediately postpartum, particularly in nulliparous mares, and is closely associated with IgG concentrations. These results suggest that antitrypsin activity contributes to the protection of IgG during intestinal absorption and should be considered when assessing colostrum quality for neonatal care.