Study Of Drug Resistance Of Eimeria Tenella By Body-testing Method And Analyze Of Isozyme

Chicken coccidiosis is caused by one kind or more kinds of Eimeria and happens worldwidely.The sickness causes harm to chicken seriously, which causes the huge economic loss in chickens industry.of all species of Eimeria, Eimeria tenella is one of the most ubiquitous and the most pathogenic for chicken. As a major way in controlling the coccidiosis in chickens,the use of anticoccidal drugs,which have been used heavily for many years,because of the long period usage of the anti-Coccidiosis drug,the drug resistance of coccidium has become an inevitable problem.In order to searching for a kind of reasonable medication project and detecting effect for resistance against anticoccidials of chicken coccidia,three Eimeria tenella strains were isolated and purified from An Qing, Fei Dong and Chao Hu broiler farms.Then, the Body-testing method was used to test the drug resistance of the three strains to four anticoccidials: Decoquinate,Nicarbazin and Zoalene,Sodium sulfa chlorpromazine.which were often used. The criteria used for evaluation the resistance included anticoccidianl index (ACI),reduction of lesion scores(RLS),percent of optimum anticoccidial activity(POAA) and relative caecum oocyst production(ROP).The results showed that An Qing stain,Fei Dong stain and Chao Hu stain all assumed the negative to decoquinate,but have a complete resistence to Nicarbazin.An Qing strain to Zoalene were: ACI 160.70(-),RLS 85.77(-),POAA 33.35(+),ROP 17.82(+),moderate resistence.The four criteria of An Qing strain to Sulfaclozine Sodium were : ACI 140.52(+),RLS 78.45(-),POAA 32.96(+),ROP 30.46(+),serious drug resistance. The four criteria of Fei Dong strain to Zoalene were: ACI 148.02(+),RLS 90.81(-),POAA 51.79(-),ROP 9.04(-),low drug resistance. The four criteria of Fei Dong strain to Sulfaclozine Sodium were: ACI 139.02(+),RLS 81.34(-),POAA 44.96(+),ROP 42.16(+),serious drug resistance. The four criteria of Chao Hu to Zoalene were: ACI 150.22(+),RLS 76.15(-),POAA 45.18(+),ROP 37.57 (+),serious drug resistance. The four criteria of Chao Hu to Sulfaclozine Sodium were: ACI 96.05(+),RLS 27.59(+),POAA 11.33(+),ROP 48.73(+),complete resistence.According to the results of drug resistance of the 3 strains E.tenenlla, taking Shanghai and Nanjing sensitive standard strains as the reference,dis-continual polyacrylamide gel electrophoresis was used to analyze 3 E.tenella strains'lactic dehydrogenase (LDH), glucose phosphoric acid isomerase (GPI) and the glucose - 6- phosphoric acid dehydrogenase (G6PD) isozyme spectrum. Nicarbazin and Sulfaclozine Sodium drug restance strains had a LDH specially isozyme spectrum, Nicarbazin drug restance strain had a GPI specificity isozyme spectrum.But Nicarbazin, Sulfaclozine Sodium and Zoalene drug restance had no relationship with G6PD isozyme.Finally,comparison the efficacy of different dose of anticoccidials between Arprinocid (30mg/kg,60mg/kg,90mg/kg) and Sulfaclozine Sodium(600 mg/kg)by weight gains,lesion scores of caecum and anticoccidial indexs(ACI).The result showed thatArprinocid 90mg/kg had the best efficacy, ACI was 187.19.