Negm-Eldin M M
Department of Parasitology, Faculty of Veterinary Medicine Moushtohour, Tukh, Benha University, Egypt.
Dtsch Tierarztl Wochenschr. 1998 May;105(5):175-81.
Trypanosoma mukasai from the blood of Clarias lazera was successfully transmitted to eight fresh water fish species using B. tricarinata as vector. Such cross transmission showed that the trypanosome was not host specific. Previously described fish trypanosome species were morphologically indistinguishable, and on the basis of the present result they were regarded as a single species, T. mukasai. Trypanosomes increased in size the longer they remained in fishes and they were observed for up to 7 months in surviving fishes. In B. tricarinata, they survived over a period of 10 months involving 18 meals after the initial blood meal, provided the fasting period did not exceed 28-80 days. Survival was attributed to residual stages in the crop. The population ecology of B. tricarinata revealed an increase of the total population and of brooding of eggs and/or youngs during spring and summer. Although, the leech fed on a broad spectrum of hosts, certain fishes such as Chrysichthys auratus were preferred. Also, certain sites (e.g. the head in C. auratus) were preferred to others. The amount of blood ingested varied from two to about three times its body weight. Time for digestion of blood was dependent on the size of the leech as well as the species of the fish. The histopathological changes at the attachment sites of leeches were studied.
利用三棱蛭作为载体，成功地将来自拉氏胡子鲇血液中的穆氏锥虫传播给了8种淡水鱼。这种交叉传播表明该锥虫并非宿主特异性的。先前描述的鱼类锥虫物种在形态上无法区分，基于目前的结果，它们被视为单一物种，即穆氏锥虫。锥虫在鱼体内停留的时间越长，其体积就越大，在存活的鱼体内观察到它们长达7个月。在三棱蛭中，在最初吸食血液后，它们在10个月的时间里存活下来，经历了18次进食，前提是禁食期不超过28 - 80天。存活归因于嗉囊中的残留阶段。三棱蛭的种群生态学显示，在春季和夏季，其总种群数量以及卵和/或幼体的育雏数量有所增加。尽管这种水蛭以广泛的宿主为食，但某些鱼类，如金头鲷，是其偏好的宿主。此外，某些部位（如金头鲷的头部）比其他部位更受青睐。摄入的血量从其体重的两倍到大约三倍不等。消化血液的时间取决于水蛭的大小以及鱼的种类。研究了水蛭附着部位的组织病理学变化。
