RESUMEN
90 samples from [liver, spleen and brain] of freshly dead and sick 4-7 days old balady chicks [with depression and mild nervous signs] were collected from different farms at Assiut Governorate. Also 120 dead in shell chicken embryos were collected from different hatcheries. Enterococcus durans was isolated at a rate of 66.6% from livers and spleens of chicks and at a rate of 27.7% from brains. The organism was isolated from dead in shell chicken embryos at a rate of 70.8% from livers and spleens and from brain at a rate of 20.8%.This indicates that the organism is transmitted through contaminated eggs from mothers or through contamination with faecal matter containing the organism. Experimental infection of healthy l day old balady chicks subeutaneously, intramuscularly and intraperitoneally with the isolated organism resulted in depression, some nervous signs and septiceamia in all chicks. Mortality rate reached to 80%, 60% and 50% in chicks which infected intraperitoneally, intramuscularly and subcutaneously respectively. Gross lesions revealed congestion and enlargement of livers and spleens, enlargement of gallbladder, petechial haemorrhages in the brains, enteritis, Congestions and enlargement of kidneys with precipitation of uric acid in the ureters. Reisolation of the organism from experimentally infected chicks was succeeded. In vitro sensitivity test revealed that the gemtamycin, ampiciilin and naladixic acid were the most effective drugs