A review on major bacterial causes of calf diarrhea and its diagnostic method

Abstract

Calf diarrheic diseases result from complex interactions of the environment. Infectious agents and the calf itself are the major constraints for raising replacement stock. Calf diarrhea is a multi factorial disease entity that can have serious financial and animal welfare implications in both dairy and beef sucker herds and is one of the most common diseases reported in calves up to 3 months old. Among the bacterial causes of diarrhea in neonatal food animals, Escherichia coli and Salmonella species are the most common and economically important ones. Clostridium perfringens and Campylobacter species have also been identified as causes of enteric diseases in calf diarrhea other, Non-infectious factors, such as insufficient uptake of colostrum, poor sanitation, stress, overcrowding in the calf pens and cold weather, could cause neonatal calf diarrhea. The most prominent virulence factors identified in bacterial diarrhea are expression of fimbrial (pili) antigens that enables the bacteria to adhere and to colonize the luminal surface of the small bowel and elaboration of one or more enterotoxins that influence intestinal secretion of fluids. Various laboratory methods have been applied for the detection of infectious agents of calf diarrhea in fecal sample such as, bacterial culture, electron microscopy, molecular based techniques (PCR, DNA microarray) and serological techniques (enzyme-linked immunosorbent assay, latex agglutination test). Accurate and rapid early confirmation of the etiology in the disease outbreak as well as improving the various management factors are advised, for effective control and prevention of enteric disease in newborn calves. Treatment with rehydration solutions and provision of dry and warm conditions are vital in the treatment of calf diarrhoea.