Abstract: Coccidia oocysts existed in the small intestine in a clinical died chicken were collected using saturation saline floatation method. After sporulation of oocysts, single oocyst was separated by 2% agarose. Seven 5-day-old chickens were inoculated with the single oocyst. After two times of passage, Eimeria maxima oocysts identified by morphology were again infected to ten 10-day-old chickens, with 1.0×10⁴ oocysts per bird. Thus, numbers of pure oocysts were obtained. The present result suggested that the single oocyst separating technique that used a blade cutting agar plate was a simple and convenient method, which had a higher success rate of single oocyst infection. Therefore, it is useful to amplify the pure oocysts.

Key words: E.maxima; single oocyst; chicken