三株柔嫩艾美耳球虫(Eimeria tenella)的繁殖力和免疫原性的比较研究

A COMPARATIVE STUDY OF THE REPRODUCTION AND IMMUNOGENICITY OF THE THREE LINES OF EIMERIA TENELLA

分别用柔嫩艾美耳球虫早熟弱毒株、鸡胚适应株和强毒株孢子化卵囊１０００个／只，给１０日龄无球虫雏鸡免疫接种，逐日检查粪便并进行克粪便卵囊（Ｏ．Ｐ．Ｇ．）计数，结果发现早熟弱毒株和鸡胚适应株的潜隐期均有不同程度缩短，繁殖力亦有不同程度的下降。同时进行了柔嫩艾美耳球虫不同株球虫的免疫原性比较：分别用三株卵囊免疫雏鸡，免疫剂量为１０００个／只，免疫后１４ｄ各用１０００个／只强毒株卵囊攻虫，逐日进行Ｏ．Ｐ．Ｇ．计数，发现各组免疫鸡攻虫后的卵囊产量均大大下降，其中以强毒株免疫攻虫组的排出卵囊量最低，仅为未免疫组的１．２３％，早熟株和鸡胚株免疫鸡攻虫的排出卵囊量相近，分别为未免疫组的７．３５％和７．２３％。由此可见，三株柔嫩艾美尔球虫均表现出良好的免疫原性。

The reproduction of the three lines(precocious line,chick embryo adapted line and the virulent line) of Eimeria tenella were studied.The precocious line and chicken embryo adapted line were found to have a shorter prepatent period than the virulant line.The prepatent period of the precocious line was the shortest.The reproduction of the precocious line and embryo adapted line were less than that of the virulent strain.The reproduction of the precocious line was the lest and only was 2475% that of the virulent strain.The oocyst production of the embryo adapted line was 7415% that of the virulent strain. In the studies on immunogenicity,the chicken was given 1000 oocyst of the precocious line or embryo adapled line or the virulent line,and was challenged 1000 of the virulent oocyst at 14th day after immunity.The reproduction of all immunity chickens was sharply decreased when chicken was challenged with the virulent oocyst.The result revealed consistently good protection afforded by the three lines.