广东省绿头鸭场鸭乙肝病毒自然携带状况调查

目的　调查两个鸭场携带乙肝病毒(DHBV)状况。方法　在对广东省家养绿头鸭分布状况进行系统调查的基础上，对南海市和顺镇、里水镇两个绿头鸭场作了随机抽样调查，采集了雏鸭、青年鸭和种鸭的血标本共519份，应用斑点分子杂交(DotBlot)测定法观察绿头鸭乙型肝炎病毒(DHBV)自然携带率。结果　两鸭场绿头鸭的DHBV自然携带率为36.0%(187/519)，其95%可信限为31.0%～44.0%。不同鸭龄组绿头鸭DHBV自然携带比较，两鸭场同日龄绿头鸭DHBV自然携带率比较，绿头鸭DHBV自然携带率的性别比较，差异均无显著意义。不同鸭龄的绿头鸭DHBV-DNA含量定量分析(A值)，差异有非常显著性(P＜0.01)，其含量由高到低顺序为雏鸭＞种鸭＞青年鸭，和顺鸭场的绿头鸭DHBV-DNA含量高于里水鸭场。结论　两鸭场绿头鸭携带的DHBV可能源于不同的亚株。

Investigation of the Natural Carrying Rate of Hepat itis B Virus of Anas Platyrhynehos Linnaeus from Two Farms of Nanhai Cit y in Guangdong Province

Objective To investigate the prevalence of duck hepatitis B virus(DHBV)in two farms. Methods A sampling survey of the duck species of domesticated Anas Platyrhynehos Linnaeus was carried out. 519 blood samples were collected from two farms in Heshun and Lishui towns of Nanhai city in Guangdong province,being from three categories,namely,newly-hatched,growing and full-grown ducks. The Dot Blot Hybredization measurement was to determine the DHBV prevalence. Results The average natural carrying rate of DHBV is 36.0%(187/519)from two farms. 95% confidence interval of the tested blood sample is within the range of 31.0%-44.0%. The differences of natural carrying rate of DHBV are nonsignficant for ducks of different ages,farms or sexes,while the differences of the values of optical density(A)of DHBV-DNA between ages are extremely significant(P<0.01),that is,the values decrease from newly-hatched to full-grown to growing ducks. The A values in Heshun farm samples are higher than Lishui. Conclusions DHBV carried by Anas Platyrhynehos Linnaeus from both farms may be probably derived from different sub-strains.