McIlroy S G, Goodall E A, McCracken R M
Department of Agriculture for Northern Ireland, Veterinary Research Laboratories, Stormont, Belfast, Northern Ireland.
Avian Pathol. 1989 Jul;18(3):465-80. doi: 10.1080/03079458908418619.
A survey of the infectious bursal disease (IBD) status of 85 clinically normal broiler flocks was carried out. Flocks were grouped into three categories: flocks without IBD lesions (category A), flocks with typical acute IBD lesions (B) and flocks with typical chronic IBD lesions (C). Category A flocks achieved a net income per 1,000 birds which was 11% better (P<0.05) than category B flocks and 14% better (P<0.01) than category C flocks. The 85 broiler houses used by the surveyed flocks during production were similarly grouped into the three categories. Analysis of production data from 991 flocks comprising 14 million birds demonstrated that flocks reared in category A houses achieved a similar superiority in net income per 1,000 birds over those flocks reared in both category B and category C houses. Food conversion ratio and average weight per bird were also superior in flocks reared in category A houses. These findings suggest that IBD virus persisted from flock to flock in category B and category C houses. The differences in performance were greatly accentuated during the winter months. The results indicate that the presence of IBD virus infection accounts for about two-thirds of the reduced profitability achieved by broiler flocks in Northern Ireland during the winter.
对85个临床正常的肉鸡群的传染性法氏囊病（IBD）状况进行了调查。鸡群分为三类：无IBD病变的鸡群（A类）、有典型急性IBD病变的鸡群（B类）和有典型慢性IBD病变的鸡群（C类）。A类鸡群每1000只鸡的纯收入比B类鸡群高11%（P<0.05），比C类鸡群高14%（P<0.01）。被调查鸡群在生产期间使用的85个肉鸡舍也类似地分为这三类。对包括1400万只鸡的991个鸡群的生产数据进行分析表明，在A类鸡舍饲养的鸡群每1000只鸡的纯收入比在B类和C类鸡舍饲养的鸡群具有类似的优势。A类鸡舍饲养的鸡群的饲料转化率和每只鸡的平均体重也更优。这些发现表明，IBD病毒在B类和C类鸡舍中在鸡群之间持续存在。在冬季，生产性能的差异大大加剧。结果表明，IBD病毒感染的存在约占北爱尔兰冬季肉鸡群盈利能力下降的三分之二。
