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Objective: Isolation of Histophilus somni (Haemophilus somnus) from pneumonic lesions in cattle.
Animals: Fifty - two samples of pneumonic lungs from slaughtered cattle.
Procedure: During a six -month period, 52 lung samples with pneumonia were collected from slaughterhouses in suburbs of Tehran for isolation of H. somni. Samples were cultured by standard bacteriological methods and isolated bacteria were identified according to Carter and Cole method by biochemical and enzymatic examinations. Antibiotic sensitivity test was performed on H. somni isolates.
Results: H. somni was isolated alone or with other bacteria from 4 (7.69 %) lungs with pneumonia. Antibiotic sensitivity test showed that the isolated bacteria were sensitive to Ceftioufur (Exenel) and Enrofloxacine but resistant to Trimethoprim, Penicillin and Streptomycin.
Conclusion: To the authors' knowledge this is the first report of H. somni isolation from respiratory system of cattle in Iran and further research is necessary about it].Fac. Vet. Med. Univ. Tehran.59,4:391-394,2004.