柔嫩艾美耳球虫对氯嗪苯乙菁和常山酮抗性快速诱导

诱导了柔嫩艾美耳球虫(Eimeriatenella)甘肃株对两种药物-氯嗪苯乙氰和常山酮的抗药性.增加实验动物数和球虫的接种剂量可加快柔嫩艾美耳球虫对氯嗪苯乙氰和常山酮抗药性的产生.每组动物用100只2～3周龄AA肉鸡，每只鸡接种2×10

Rapid Development of Drug-resistant Strains of Eimeria tenella to Diclazuril and Halofugenone in Laboratory

The development of resistance of the GS strain of Eimeria tenella to the anticoccidial drugs halofugenone and diclazuril has been studied. Resistance to halofugenone and diclazuril developed readily in experiments where a large number of coccidia were exposed to the drugs, either by increasing the number of oocysts in the inoculum or by increasing the number of birds in the group. When 100 birds were given 2 x 106 oocysts commenced from an initial concentration of 0.6×10-6 halofugenone or 0.125×10-6 diclazuril, resistance to halofugenone and diclazuril appeared after 6 and 5 passages respectively. The passaged lines did not recover their sensitivity to these 2 chemicals after 5 further passages in absence of the use of drug, suggesting that the resistance developed was stable. 7 anticoccidial drugs, salinomycin, monensin, maduramycin, lasalocid, zoalene, nicarbazin and clopidol were effective against halofugenone- and diclazuril-resistant line of E. tenella, suggesting that halofugenone and diclaruril did not exhibit cross-resistance with the above-mentioned compounds.