文献类型： 外文期刊

作者： Sun, Hongchao ¹ ; Su, Xinyao ¹ ; Fu, Yuan ¹ ; Hao, Lili ² ; Zhou, Wei ³ ; Zhou, Zhijin ³ ; Huang, Jing ³ ; Wang, Yimin ⁴ ; Shi, Tuanyuan ¹ ;

作者机构： 1.Zhejiang Acad Agr Sci, Inst Anim Husb & Vet Med, Dept Anim Parasitol, Hangzhou 310021, Zhejiang, Peoples R China

2.Southwest Minzu Univ, Coll Anim & Vet Sci, Dept Anim Parasitol, Chengdu 610041, Sichuan, Peoples R China

3.Zhejiang Prov Anim Dis Prevent & Control Ctr, Dept Vet Med & feed, Hangzhou 311199, Zhejiang, Peoples R China

4.Hangzhou Caiyang Agr Sci, Hangzhou 311321, Zhejiang, Peoples R China

关键词： Key words; Eimeria tenella; isolate; pathogenicity; drug resistance

期刊名称：POULTRY SCIENCE （ 影响因子：4.4； 五年影响因子：4.4 ）

ISSN： 0032-5791

年卷期： 2023 年 102 卷 8 期

页码：

收录情况： SCI

摘要： Chicken coccidiosis can cause severe enteritis with high mortality, which causes serious eco-nomic losses to the global breeding industry each year. The most virulent species is Eimeria tenella (E. ten-ella), but the infectivity of different E. tenella varies among geographic strains. At present, there are no reports related to the pathogenicity and drug resistance of E. tenella in Yiwu, Zhejiang province, China. A total of 600 fecal samples were collected from 10 farms in Zhe-jiang province, the overall oocyst prevalence was 54.2% (325/600). The prevalence was significantly higher (P < 0.01) in chickens under 40 d (97.5%) than that in chick-ens between 60 and 85-days-old (40.5%) and chickens over 90-days-old (24.5%). E. tenella stain was isolated from fecal samples of chickens in Yiwu and the pathoge-nicity of this isolate was determined, and then we recorded the survival rate, bloody stool score, lesion score, average weight gain. The results showed that all of the chickens infected with 5 x 105 sporulated oocysts of E. tenella died after the seventh day of infection, the bloody stool score and average lesion score of chickens from group 1 (5 x 105), group 2 (5 x 104), group 3 (5 x 103) and group 4 (5 x 102) decreased successively; the average weight gain (g) and relative weight gain (%) increased successively; the weight gain of the low-dose E. tenella infection groups (5 x 103 and 5 x 102) were higher than the other 2 groups (5 x 105 and 5 x 104) (P < 0.05). Finally, The E. tenella isolate was tested for sen-sitivity to 6 anticoccidial drugs (sulfachloropyrazine sodium, amproline, toltrazuril, clopidol, salinomycin, and nicarbazine) using 4 indexes including anticoccidial index(ACI), percent of optimum anticoccidial activity (POAA), reduction of lesion scores (RLS), and relative oocyst production (ROP). The results showed that this isolate has developed severe resistance to drugs of salino-mycin and nicarbazine, moderate resistance to ampro-line and clopidol, slight resistance to toltrazuril, while the E. tenella isolate performed more sensitive to sulfa-chloropyrazine sodium.