Abstract: One chicken farmer sent me ten diseased chickens of 17day old. I was told there are altogether 5,100 chickens in the farm. The disease occurred from 2 days old. A few died on the third day. Death of chickens increased during 6 to 7 days period. About 20 died each day. More chickens died among the 12day old, with about 100 each day. The clinical signs are: progressive ataxia to paralysis, tremor of the head and neck, legs sitting on hocks and falling onto its side, and chirming. In order to further confirm and find out more efficient cure methods, the author anatomized chickens of this case, and applied methods of specimen, serology, and pathology, etc. Considering factors of dates of disease, clinical signs, pathological changes, and ELISA tests, the author diagnosed that the blood serum sample from delivered chickens are avian encephalomyelitis. 

Key words: encephalomyelitis; pathology; ELISA; serology