摘要
本文报告在青海乐都药草台高原牧场观察绵羊小肠卵形斯氏吸虫（ｓｋｒｊａｂｉｎｏｔｒｅｍａｏｖｉｓ）生活史各期的情况。自１９７９至１９８２年间有三个夏天在新疆天山牧场和青海乐都药草台对本问题进行考察，从新疆和青海的绵羊均检获大量的本吸虫童虫和成虫。在青海东部一些地区羊的感染率约６％～３３％，感染强度可达１０００～５００００条虫。乐都药草台上的陆地蜗牛为康特大蜗牛（Ｈｅｌｉｃｅｌａｃａｎｄａｃｈａｒｉｃａ），它是本吸虫的第一中间宿主（感染率为０．３５％～１３．００％），也是它的第二中间宿主（感染率为２１．２８％～８６．４９％，感染强度为１～３２条后蚴）。本吸虫的胞蚴及其中的尾蚴在蜗牛的消化腺中发育。成熟尾蚴离开蜗牛宿主进入另一个蜗牛体中围心腔中继续发育。每一阳性蜗牛围心腔中含有不同发育程度的本吸虫后蚴，从仍保持成熟尾蚴形态结构的早期后蚴，仍保留有尾部的中期后蚴，至已无尾部的成熟后蚴。成熟后蚴的形态结构与绵羊小肠中本吸虫的早期童虫极为酷似。
The present communication reports the results of an investigation on the biology of skrjabinotrema ovis of sheep on Qinghai Plateau,which was undertaken during three summers from 1979 to 1982.The adult specimens were collected from positive sheep in Yaocaotai of Ledu County,Qinghai Province,and from Xinjiang Autonomous Region.The larval stages of S.ovis were collected from positive landsnails, Helicella candacharica in the endemic pasture on Yaocaotai highland about more than 4000 m.above the sea level. The incidences of S.ovis infection in sheep on Yaocaotai were 6%～33%,about 1000—50000 juveniles and adults of this trematode species were found from the small intestine of each positive sheep.The infection rates of the larval stages of S.ovis in its first intermediate host, H.candacharica ,were 0 35%～13%,average 0 93%(20/2 163).The positive landsnails containing branched sporocysts and mature cercariae were found from July to September in 1981 and 1982.The same species of landsnail, H.candacharica, also act as the second intermediate host of S.ovis on Yaocaotai Plateau.The infection rates of S.ovis metacercaria in H.candacharica were 21 28%～86 49%,average 45 58%(67/147),their densities were 1～32 worms,average 7 3(487/67),in the positive snails.The positive land snails contained early metacercariae,Young metacercariae and mature metacercariae in their pericardia. Young branched sporocysts were about 3 556 mm×0 289 mm in length and width,they contained many cercarial germ balls.Mature sporocysts,about 3 865 mm×0 265 mm,contained different developmental stages of cercaria,from germinal cells and germ balls to mature cercariae.Cercaria of S.ovis is microcercous cercaria.There are two posterior excretory ducts leading from the posterior edge of excretory vesicle into the small tail,both of which open at the left and right posterolateral corners of the tail.Sometime,a rudimentary median duct could be seen in the tail. In the pericardium of H.candacharica,
出处
《寄生虫与医学昆虫学报》
CAS
1999年第1期24-30,共7页
Acta Parasitologica et Medica Entomologica Sinica
关键词
绵羊
卵形斯氏吸虫
康特大蜗牛
生物学
生活史
Skrjabinotrema ovis \ Helicella candacharica \ Biology Life cycle Qinghai Plateau
