Cell-Mediated Immunity in the Neonatal Calf

Abstract

Bovine colostrum contains viable leukocytes. The phenotypes and biologic responsiveness as well as clinical significance of colostral lymphocytes will be reviewed. From the reviewed data, possible functions of these cells will be discussed. In addition, new data that describes absorption, viability, activation states and the repertoire expression of T-lymphocytes will be presented. Information of the kinetics of lymphocyte absorption, positive and negative selection, and function in the immune system of neonatal calves will also be presented. Maternally derived lymphocytes probably have a major role in the initiation, maturation and regulation of immune responses in the newborn calf.