Immunological Dysfunction in Periparturient Cow

Abstract

Periparturient cows are immunosuppressed. Critical neutrophil functions (egress and phagocytic activities) and lymphocyte functions (immunoglobulin and cytokine secretion) are all impaired during this time. Exact causes ofperiparturient immunosuppression are not known but tremendous fluxes in endocrine factors undoubtedly effect changes in immunological competence. Periparturient cows experience large changes in plasma concentrations of vitamins and also are adjusting to the calcium, energy and protein demands necessary for lactation. The end of gestation appears to induce a progressive suppression of immune function. There appears to be a teleological basis for suppression of antigen specific immunity in the periparturient female. Development of immunity against self and paternal antigens released into the cow as a consequence of tissue damage associated with parturition would serve little useful purpose. However, as a result of this suppression, innate immune function is also impaired (perhaps inadvertently) and opportunistic infections such as mastitis and metritis occur with increased frequency in postpartum cows.