Abstract:

This study was aimed to explore the pathogenesis of calf diarrhea in a large scale dairy farm in Shanxi province and the correspond comprehensive prevention and control measures. By investigating the incidence of calf diarrhea in the field, rotavirus, coronavirus,E. coli F5 (K99),Cryptosporidium parvum, coccidia and Salmonella were detected through experimental diagnosis, and the suspicious pathogenic bacteria was isolated and cultivated,which was identified with morphology and serology, simultaneously sensitive antibiotics were screened according to the antibiotic susceptibility tests, which contained 18 kinds of common antibiotics. The results showed that the clinical diagnosis and laboratory tests basically ruled out the possibility of E. coli F5 (K99), rotavirus, coronavirus, Cryptosporidium parvumand coccidia infection, and the isolated suspected bacteria had Salmonella colony characteristics and bacterial morphology, which showed positive reaction to Salmonella O polyvalent A-F serum, so we had identified that it was Salmonella diarrhea.The antibiotic susceptibility tests results showed that Salmonella was highly sensitive to ceftriaxone, gentamicin, cephradine and amikacin, which could be recommended for clinical treatment. Above all, this study proposed the specific prevention and treatment of the disease, and better control effect was achieved. This study initially provided a reference for the diagnosis and treatment of Salmonella of calf diarrhea, with great clinical significance in the early diagnosis and treatment of pathogens of calf diarrhea.

Key words: calf diarrhea; Salmonella; diagnosis and treatment