Blood leukocytes, neutrophil phagocytosis, and plasma corticosteroids in colostrum-fed and colostrum-deprived calves.

Blood leukocyte patterns, neutrophil phagocytosis of killed Escherichia coli in vitro, and plasma corticosteroids were studied in colostrum-fed (CF) and colostrum-deprived (CD) calves during the 1st 144 hours after birth. There was a marked increase in neutrophil numbers between 6 and 12 hours in CF but not CD calves, apparently as a result of colostrum ingestion. Phagocytosis was inactive at birth but increased quickly thereafter. Phagocytosis was more efficient in CF than in CD calves. Plasma corticosteroid concentrations were high at birth and decreased quickly thereafter in both groups of calves.