化学致弱柔嫩艾美耳球虫杂交F2株免疫性能研究

Study on Immune Performance of Eimeria tenella Hybridization F2 Strain Attenuated by Chemical Preparation

采用化学致弱剂致弱柔嫩艾美耳球虫杂交F2株卵囊。将致弱的卵囊分别饲喂3组7日龄AA肉仔鸡进行免疫,免疫剂量分别为4×103,8×103,16×103个/只。首免7日龄,二免14日龄,二免剂量与首免相同。二免后第7 d用吉林野毒株卵囊进行攻虫,剂量为5×104个/只。攻虫后第7 d以存活率、相对增重率、病变值、抗球虫指数(ACI)、卵囊值、粪便计分等指标测定化学致弱剂致弱卵囊后免疫性能。结果表明:采用化学致弱剂致弱杂交F2株卵囊后的免疫效果明显高于非致弱免疫组和对照组,尤其免疫剂量为8×103个/只时致弱杂交F2株卵囊免疫效果最佳。

Eimeria tenella hybridization F2 strain oocysts were attenuated by chemical preparation. The 7-day old AA broilers were selected in this test. Attenuated hybridization F2 strain oocysts were inoculated to 3 groups of broiler to detect immune performance of E. tenella. The first immunity doses to be inoculated were 4 ×~ 10^3, 8 × 10^3, 16 × 10^3 oocysts per group, and the second immunity doses were the same. The first immunity day was the 7^th day, and the second was the 14th day. On the 21th day, broilers were attacked by using 5 × 10^4 wild strain oocysts per broiler. On the 7th day after attack, immune performance was detected through survival rate, relative weight gain rate, pathological change value, anticoccidial in- dex（ACI） ,oocyst value, feces record and caecum lesion record, etc. The results showed that immune performance of E. tenella hybridization F2 strains oocyts attenuated by chemical preparation are much higher than that of those not attenuated and controlled, especially the immune effectiveness that was 8 × 10^3 attenuated E. tenella hybridization F2 strain oocyts to be inoculated is the optimal.