Wang C-H, Juan Y-W
Department of Veterinary Medicine, National Taiwan University, P. O. Box 23-3, Taipei 106, Taiwan.
Avian Pathol. 2002 Oct;31(5):435-9. doi: 10.1080/0307945021000005806.
There are three grandparent farms for three different chicken breeds in Taiwan. One of these farms, populated by breast meat yield chickens (yield type), suffered from a severe subgroup J avian leukosis virus (ALV-J) infection in mid-1997. The affected flocks at that farm had a weekly mortality of more than 1% and a 15% drop in egg production. The broilers from that breed had a 10% condemnation rate during the first week of age, and 5% of the remaining broilers were stunted afterwards. Some chickens had myeloid leukosis lesions at 6 weeks old. Their survivability was about 85%. However, chickens at the other two grandparent farms, populated with non-yield chickens (regular type), were also infected by ALV-J and showed myeloid leukosis. However, chickens at these farms produced progeny whose survivability reached more than 95%. ALV-J caused greater economic loss in yield type chickens than in regular type chickens in Taiwan.
台湾有三个祖代种鸡场，分别饲养三种不同的鸡品种。其中一个饲养肉用仔鸡（产肉型）的鸡场在1997年年中遭受了严重的J亚群禽白血病病毒（ALV-J）感染。当时，该鸡场受感染的鸡群每周死亡率超过1%，产蛋量下降了15%。该品种的肉仔鸡在1周龄时的淘汰率为10%，剩余肉仔鸡中有5%随后发育不良。一些鸡在6周龄时出现髓细胞性白血病病变。它们的存活率约为85%。然而，另外两个饲养非产肉型鸡（常规型）的祖代种鸡场的鸡也感染了ALV-J，并出现了髓细胞性白血病。然而，这些鸡场的鸡所产后代的存活率达到了95%以上。在台湾，ALV-J给产肉型鸡造成的经济损失比常规型鸡更大。
