青海省青南高原与柴达木盆地细粒棘球蚴实验感染犬体内成虫形态学比较观察

Morphological comparison and observation on protoscolices of Echinococcus granulosus in experimentally infected dogs from Southern Qinghai Plateau and Chaidamu Basin

目的比较青南高原与柴达木盆地两地细粒棘球绦虫成虫形态学特征,为虫株研究提供依据。方法选择青南高原的黄南州同仁县、柴达木盆地的德令哈市为采样点,采集当地自然感染,发育良好的绵羊棘球蚴囊,分别人工感染实验犬,45 d后粪检绦虫卵阳性时剖杀,取其肠道成虫,AAF固定液固定,成虫虫体用洋红或苏木素染液染色,切取的顶突钩用4%孔雀绿染液染色。低倍镜下观察其形态学特征并用测微尺测量,记录结果。结果德令哈株细粒棘球绦虫成虫多数为4节,黄南株多数为5节;德令哈株成虫链体较细长,黄南株较宽短,两株虫体总长度差异有显著性(P<0.05);黄南株成虫成熟节片睾丸数与德令哈株比较差异无显著性;黄南株睾丸在生殖孔前后的分布相当,而德令哈株睾丸多分布于生殖孔前。两成虫生殖孔位置都位于链体节片偏后,但德令哈株有6.84%的生殖孔偏前。黄南株成虫雄茎囊明显小于德令哈株;虫体头钩总数多于德令哈株,大钩、小钩总宽均>德令哈株,头钩总长两成虫间差异无显著性(P>0.05)。结论青南高原和柴达木盆地两地细粒棘球绦虫虫体在某些形态特征上显著不同,提示我国可能存在不同的地理株。

Objective To compare morphological characteristics of Echinococcus granulosus from Southern Qinghai Plateau and Chaidamu Basin, and to provide basic data for strains research. Methods The dogs were laboratorially infected with echinococcus cysts which were isolated from natural and well-developed sheep bred in Tongren County of Southern Qinghai Plateau and Delingha City in Chaidamu Basin. Adult worms were collected from intestinal tract to observe its morphological characteristics under microscope, the length of adult worms were also measured. Results Most of E. granulosus form Delingha City had four segments, and its body was long and thin. The strains of worms from Tongren County had five segments, its body was wide and short. The total worm length had significant different between two kinds of strains （P〈0.05）. The position of genital pore of these strains were behind of body segment, but 6.84 % of the position of genital pore of worms from delingha city was before the body. segment. Cirrus sac of worms from tongren count was obviously lower than that of total number of hooks and the total widen of large hooks and small hooks of E. granulosus from Tongren County were larger than that of Delingha City＇s. The total length of hooks had not significant difference. Conclusion There are significant difference of E. granulosus from Southern Qinghai Plateau and Chaidamu Basin, it is possible of existing different genotype strains of E. granulosus.