DETERMINATION OF LETHAL EFFECT OF TOXIN EXTRACTED FROM STAPHYLOCOCCAL INFECTION IN COMMERCIAL BROILER FLOCK WITH ISOLATION, IDENTIFICATION AND ANTIBIOGRAM STUDY OF IDENTIFIED FIELD ISOLATE

Abstract

The present research work was carried out to the study of isolation and identification of the etiological agent of Staphylococcal infection in commercial broiler flock having typical symptoms with antibiogram study and extraction of toxin from field isolate and determination of lethal effect of toxin in day old chicks. The sample (pus/fluid) were collected from the suspected birds and shifted aseptically to the Bacteriology laboratory of the Department of Microbiology, Hajee Mohammed Danesh Science and Technology University, Dinajpur. The samples were subjected to bacteriological examination for isolation and characterization of bacteria. Locally available antibiotic discs were used for determining the degree of drug sensitivity against the Staphylococcus isolates. The study shown that the highest percentage of occurrence (52.17%) of Staphylococcus aureus was obtained from group A followed by group B (41.67%) and group C (20.0%). Prevalence of toxicity in case of day old chick those were given toxin orally was 30% and in case of chicks those were inoculated subcutaneously was 10%. Out of 30 day old chicks 04 died and average prevalence of toxicity is 20%. In postmortem examination it was found that tenosynovitis, most commonly in the plantar area of the foot or just above the hock joint. This was progress to abscess formation in these areas. Infected joints had clear exudate with fibrin clots. The abdomen felt soft, mushy, flabby and enlarged. Lesions associated with heavy challenge of infection generally consist of congestion of internal organs, including the liver, spleen, kidneys, and lungs, accompanied by areas of tissue death. The staphylococcus aureus highly sensitive to different antimicrobial agents such as 100% sensitive to Ciprofloxacin, Doxycycline, Penicillin, Gentamicin; 70% sensitive to Nitrofurantoin; 60% sensitive to Azithromicin and resistance to Cephradine, Ampicillin, Amoxicillin, Sulfomithoxazole X Trimethoprim.