摘要
使用从发生马立克氏病(Marek′s disease,MD)肿瘤的病鸡中分离的整合有禽反转录病毒长末端重复序列的马立克氏病病毒(Marek′s disease virus,MDV)GXY2株进行鸡的致病性试验。将试验鸡分成A、B、C、D和E共5组,B^E组鸡在1日龄接种MDV疫苗,其中B和D组鸡接种CVI988/Rispense株,C和E组鸡接种HVT株冻干疫苗,A组为未免疫组。在试验鸡8日龄时,A、B和C组鸡用GXY2株进行腹腔攻毒,D和E两组为未攻毒组。全部试验鸡均按常规方法饲养直至攻毒后(PC)82 d。记录和解剖试验期间死亡的鸡以及试验结束时剖杀的全部幸存鸡,检查肉眼可见MD肿瘤病变并应用已建立的禽肿瘤PCR鉴别诊断技术进行验证。结果表明:A、B和C组鸡最早因MD肿瘤而死亡的时间分别在攻毒后第25 d、77 d和29 d;在攻毒后82 d,前述三组鸡中的MD肿瘤发生率分别为72%、34.8%和50%,死亡率分别为84%、21.7%和20%;CVI988/Rispense株和HVT株对GXY2株攻击的保护率分别为51.67%和30.56%;在全部试验鸡的各种内脏器官中,以心脏的MD肿瘤发生率最高(23.5%),其次是肝脏(14.7%)和肌胃(10.3%);GXY2株可以显著抑制未免疫鸡的增重并导致其胸腺和法氏囊严重萎缩。本试验的结果表明,GXY2分离株具有快速致瘤特性,并且可以突破疫苗株HVT和CVI988/Rispense提供的免疫保护。
The pathogenicity of a field isolate of Marekis disease virus （MDV） named GXY2 integrated with retroviral long terminal repeat （LTR） sequence from a chicken with MD tumors was evaluated. Experimental chickens were divided into group A, B, C, D and E. The later four groups were vaccinated on oneday-old with CVI988/Rispens for group B and D, with HVT for group C and E, while group A was taken as no-vaccinated control. On 8-day-old, group A, B and C were challenged with GXY2 by intra-abdominal injection, group D and E were kept as un-challenged control. All the birds were raised routinely until 82 days post-challenge （PC）, died birds during the experiment and the slaughtered birds at the end of the experiment were necropsied and examined for gross lesions of MD and further confirmed by a developed polymerase chain reaction （PCR） based differential diagnosis technique for avian neoplastic diseases. The results showed that time of onset of MD death of group A, B and C were PC 25, 77 and 29 days with the incidences of visible MD visceral tumors. On PC 82 days, tumor incidences and mortalities of group A, B andCwere 72%, 34.8% and 50%, 84%, 21.7% and 20%, respectively. The vaccination protection of CVI988/Rispense and HVT were 51.67% and 30.56% respectively. Among all the visceral organs, heart had the highest tumor incidences （23.5%）, and then followed by liver （14.7%） and gizzard （10.3%）. The weight-gain of unvaccinated birds was significantly depressed and severe dystrophy of thymus and bursa of Fabricius were also found. The results of the study demonstrated that isolate GXY2 possessed the ability of causing acute tumors and overcoming the protection of the vaccinations of either CVI988/Rispense or HVT.
出处
《病毒学报》
CAS
CSCD
北大核心
2009年第5期376-381,共6页
Chinese Journal of Virology
基金
国家自然科学基金项目(30860206
30460099
39860055)
广西大学重点项目(2005ZD01)~~
