Bacteriological studies on calves affected with respiratory manifestations

Bovine respiratory disease (BRD) is the most common and costly disease affecting beef cattle calves in the world. The objectives of this study were to put a high light on epidemiology of P. multocida and M. haemolytica as important causes of bovine respiratory disease (BRD) in Egypt Governorates; Giza, El-Fayoum, BeniSuef, Assiut and Sohag. A total number of 406 deep nasal swabs and blood samples were collected from 406 bovine calves suffered from respiratory manifestations reared in different Governorates in Egypt. Bacteriological examination was achieved and isolation of P. multocida and M. haemolytica were attained. The overall prevalence of both P. multocida and M. haemolytica was of 26.6%; 18.2% for P. multocida and 8.4%for M. haemolytica. EL-Fayoum Governorate showed the highest prevalences while Beni-Suef Governorate showed the lowest prevalences. P. multocida was singly isolated from 4.9% of cases. While it was mixed with S. aureus, E. coli, Streptococcus spp., both S. aureus and E. coli, both S. aureus and Streptococcus spp. and both E. coli and Streptococcus spp. with percentages of 4%, 1.2%, 2.2%, 1.7%, 3.2% and 1.0%, respectively. Meanwhile, M. haemolytica was isolated as a single isolate from 1.7% of cases while it was mixed with S.aureus, Streptococcus spp., both S. aureus and Streptococcus spp. and both E. coli and Streptococcus spp. with percentages of 2.7%, 1.2%, 2.5% and 0.2%, respectively. In conclusion respiratory manifestations are very important disorders in bovine calves. P. multocida and M. haemolytica are the most common bacteria causing infection.