Abstract:
A specific-pathogen-free (SPF) chicken colony was maintained with successive groups a month apart in age. The absence of specific pathogens, including chicken anemia virus (CAV), was confirmed through periodic serological tests for each group. However, some groups became CAV seropositive. The procedures of removing seropositive and the adjacent seronegative chickens followed with chemically disinfecting the housing did not halt CAV outbreaks. The full genome sequence of the CAV strain that appeared was closely related to low-virulence isolates in China. The outbreaks of CAV decreased with an increase in the seropositive chicken population, indicating that the progeny is protected from CAV infection by maternal anti-CAV antibodies. The persistence of CAV in erythroid and lymphoid tissues or reproductive tissues from CAV seropositive chickens was examined in chickens of various ages using polymerase chain reaction (PCR). Since a low persistence of CAV was observed in the colony, we isolated eggs from CAV seropositive hens through artificial insemination using semen collected from roosters and confirmed as CAV-free by PCR. Fertilized eggs were transferred to a new SPF facility and used for generating CAV-free progeny. To date, chickens reared in the new facility have been CAV-free for longer than two years. Redirection of eggs from seropositive hens was an effective means of eliminating CAV from chickens.
摘要:
连续组以一个月的年龄间隔维持无特定病原体(SPF)的鸡菌落。缺乏特定的病原体,包括鸡贫血病毒(CAV),通过每组的定期血清学测试得到证实。然而,一些组成为CAV血清阳性。去除血清阳性和邻近的血清阴性鸡的程序,然后对房屋进行化学消毒,并没有阻止CAV爆发。出现的CAV株的全基因组序列与中国低毒力分离株密切相关。CAV的爆发随着血清阳性鸡种群的增加而减少,表明子代受母体抗CAV抗体保护免受CAV感染。使用聚合酶链反应(PCR)在不同年龄的鸡中检查了CAV在红细胞和淋巴组织或CAV血清阳性鸡的生殖组织中的持久性。由于在菌落中观察到CAV的持久性较低,我们使用从公鸡中收集的精液通过人工授精从CAV血清阳性的母鸡中分离出卵子,并通过PCR确认为无CAV。将受精卵转移到新的SPF设施中,并用于产生无CAV的后代。迄今为止,在新设施饲养的鸡已无CAV超过两年。从血清阳性母鸡中重新定向卵是消除鸡CAV的有效方法。