ISOLATION AND IDENTIFICATION OF PATHOGENS FROM PNEUMONIC LUNGS OF SHEEP AND THEIR HISTOPATHOLOGICAL CHANGES IN DIFFERENT AREAS OF SYLHET CITY

Abstract

The important feature of the present study was investigated the pneumonic lungs of sheep and their pathological conditions after slaughtered in different slaughter houses/places of Sylhet city another things isolation and identification of causal agents, antibiotic sensitivity test of were commonly used antibiotics in veterinary practices in our country. During the period from January to June 2016, a total of 300 lungs of slaughtered sheep were examined individually and out of which 80 (15.0%) become affected and lungs were collected for histopathology and bacterial isolation respectively. The gross examination of lungs showed that 40% (120 out of 300 lungs examined) were found positive for pneumonic sheep lungs. The lesions were categorized into (a) hemorrhages 40% (b) congesion 26% (c) hemorrhage with congestion 20% (d) fibrosis of lungs 7% and (e) hepatization in lungs 7%. In histopathological examination, lesions were categorized into (a) bronchopneumonia 26% (acute catarrhal bronchopneumonia 18% and purulent bronchopneumonia 8%), (b) interstitial pneumonia 20%, (c) broncho-interstisial pneumonia 25%, (d) fibrinous pneumonia 22% (e) verminous pneumonia 7%. The highest prevalence of pneumonic lungs was found in bronchopneumonia (26%) and then bronchointerstitial pneumonia (25%) and fibrinous pneumonia (22%). The organisms isolated from the affected lungs were E. coli. (20%), Staphylococcus sp. (25%), Streptococcus sp. 15%, Salmonella sp. 15%, Pasteurella sp. 25%. Finally antibiotics sensitivity test was performed on isolated bacteria. The isolates of Streptococcus sp. and Staphylococcus sp. were highly sensitive to Erythromycin, Ceftriaxone, Nalidixic acid, Penicillin, Chloramphenicol and Gentamycin. On the other hand, antibiotic sensitivity pattern of isolated Escherichia coli and Salmonella sp. were highly sensitive to erythromycin, ceftriaxone, Cefalexine, Nalidixic acid, Gentamycin. The Pasteurella sp. were highly sensitive to Nalidixic acid, Erythromycin, Co-Trimoxazole, Gentamycin, Ceftriaxone, Chloramphenicol & resistant to Penicillin, Ampicillin and Bacitracin. In consideration of the most effective antimicrobial agents against all the tested isolates, Gentamycin, Ceftriaxone, Erythromycin and Nalidixic acid are the drugs of choice for the treatment of pneumonic sheep