Infectious Diseases of the Bovine Lower Gastrointestinal Tract and the Immune Response

Abstract

Of what significance is modern-day immunology with its T and B lymphocytes, various immunoglobulin classes and subclasses, transfer factor, suppressor cells, immunosuppressive factors, and immunodeficiency diseases to everyday bovine practice? The amount of talent being devoted to continuing education in this area might suggest that it is grossly over-rated. However, when we consider that the control, diagnosis and prevention of some of the major disease problems of cattle, namely, tuberculosis, brucellosis, blackleg, virus diarrhea, infectious bovine rhinotracheitis and vibriosis, to name a few, are being conducted principally with immunological tools, possibly it is not over-rated. If we further accept that a major portion of our practice problems are related to infectious diseases of epithelial surfaces, namely the respiratory, digestive, reproductive system and mammary gland; that failure of immunity in its broadest context, whether of animal origin or management-induced, plays an important role in infectious disease, the onus is on us as veterinarians to understand the immune system so that we may use it to our best advantage.