الفهرس | Only 14 pages are availabe for public view |
Abstract The analysis was based on collecting about 110 diseased and freshly dead broiler chickens (aged from 1 to 45 days old) and 65 dead in shell chicken embryos. 1-The clinical signs and PM lesions of the naturally infected birds were described and discussed. 2-Bacteriological examination was conducted in order to isolate Enterococcus bacteria. • Then the positive colonies on KF streptococcal agar were cultured onto bile esculine azide agar and 6.5% NaCl broth and incubated at 37°C for 24 hours. The results were as follows:- • the percent of isolated Enterococcus spp. from bile esculine test & 6.5% NaCl broth culture represent about (61.8%) in liver,spleen & heart, (57.3% )in intestine, (10% ) in joint,( 8.2%) in brain and 34 from 65 samples(52%) dead in shell chicken embryos. • Enterococcus isolates were also cultured on MacConky agar No.2 and Sheep blood agar and incubated at 37°C for 24 hours. • All the Enterococcus isolates were having the ability to grow at 10 and 45°C and the biochemical reactions revealed that the isolated organism was catalase-negative and positive for gelatin hydrolysis and the organism was non- motile, positive to starch hydrolysis and litmus milk test,no pigment production and no hemolysis. 3- Classification of Enterococcus isolates according to biochemical tests as follow: • E. hirae was isolated from liver, spleen and heart (66.2%), intestine (66.7%), joint ( 81.8%),brain (66.7%) and dead in shell chicken embryos (44.1%). • E. durans was isolated from liver, spleen and heart (22%), intestine (14.2%), joint (18.1%), brain (33.3%) and dead in shell embryos (41.2%). • E.fecalis was isolated from liver, spleen and heart (11.8%),intestine (19%) and dead in shell chicken embryos (14.7%) and did not isolated from joint or brain. 4- The pathogenicity test: • E.hirae isolate and 4-day-old cobb broiler chicks were used in this experiment. • Clinical signs,pm lesions,deaths and mortality rates were reported and discussed. • In an attempt to re-isolate E.hirae from the inoculated chicks and contact chicks, the organism was reisolated from internal organs and biochemically tested. 5- Antimicrobial sensitivity test: E.hirae isolates were resistance to oxytetracycline, co-trimoxazole, enrofloxacin, oxacillin, tetracycline, erythromycin and doxycycline, also sensitive to ampicillin and neomycin, intermediate to amoxicillin and penicillin g. |