日本のブロイラー産業におけるコクシジウム感染の調査 : 1973年秋と冬, および綜合成績

抄録

Field surveys on coccidial infection in Japanese broilers were performed with 210 fecal samples collected from 24 prefectures in September (as autumn season) and December (as winter season) in 1973. Oocysts were detected from 61% of the samples tested in September. Single and mixed infection with the acervulina type oocysts were found in 59% of the samples tested, or in 96% of the oocyst-positive samples. Those with the tenella type oocysts were detected in 16% or in 26% and those with the maxima type oocysts in 15% or in 25%, respectively. No brunetti type oocysts were detected. Similar results were obtained from a survey conducted in December. Eimeria mitis was isolated from 2 fecal samples. The summarized results of the surveys conducted throughout the four seasons in 1973 were analyzed statistically, together with the results described in the previous report [9]. Oocysts were detected from 67% of the 399 samples tested. Oocyst detection rates were significantly low in groups of young age up to 30 days. Neither seasonal nor regional differences were observed in oocyst detection rate or oocyst type distribution. E. acervulina was a predominant on all Japanese broiler farms and throughout the year of 1973.