鸡球虫苗(LCV-2号)安全性和免疫效果研究

Efficacy of the vaccine (LCV-2) against chicken coccidiosis

在实验条件下,研究了鸡球虫苗LCV-2号对笼养鸡的安全性和免疫保护效果.试验设空白对照组、攻虫对照组、免疫1组（1个免疫剂量）、免疫2组（2个免疫剂量）和免疫3组（0.5个免疫剂量）,共5个试验组,每组10只鸡.试验结果表明：①空白对照组、攻虫对照组和三个免疫组的相对增重率依次为100%、84.0%、96.9%、91.0%和91.0% ②攻虫后第8 d,每组剖检2只鸡,肠道病变记分5个组依次为0、4、1、3和4分.③免疫期间,免疫1、2和3组的每克粪便卵囊数（OPG）平均值依次为4.2×103个、9.2×103个和5.4×103个 攻虫期间,攻虫对照组5.117×105个、免疫1、2和3组依次为0.797×105个、0.522 × 105个和1.171×105个.④攻虫后各组死亡率依次为0、75%、25%、25%和50%.⑤抗球虫指数（ACI）,5个组依次为200.0、88.0、166.9、148.5和120.0.总的来看,免疫鸡群对大剂量卵囊攻击有较强的抵抗力,其中免疫1组结果良好,免疫2组和3组结果尚不理想,因此,LCV-2免疫1组的剂量（1头份卵囊/只）为优选剂量.

This study examined the safety and efficacy of LCV-2 vaccine against coccidiosis in caged Lingnanhuang female broilers. The experiment was conducted in 5 trial groups （n=10）, including blank control, positive control, immunized group 1 （receiving 1 vaccine dose）, immunized group 2 （receiving 2 doses）, immunized group3 （receiving 0.5 dose）. The results showed that average ratio of weight gain of 5 groups were 100 % （blank control）, 84.0 % （positive control）, 96.9 % （immune group 1）, 91.0 % （immune group 2） and 91.0 % （immune group 3）, respectively. The intestinal lesion scores were 0, 4, 1, 3 and 4 for respective groups. The average OPG of 3 vaccinated groups were 4.2 x 103, 9.2 x 103 and 5.4 × 10^3. Following challenge infection, the OPG of the positive control and the 3 immunized groups were 5.117 × 10^5, 0.797 × 10^5, 0.522 × 10^5 and 1.171 × 10^5, respectively. The mortality rates of 5 groups were 0, 75 %, 25 %, 25 %, 50 %, and the ACI were 200.0, 88.0, 166.9, 148.5, and 120.0, respectively. In conclusion, the vaccinated chickens were better protected, with the immunized groupl performing the best.