Ekanem A P, Obiekezie A, Kloas W, Knopf K
Institute of Oceanography, University of Calabar, P.M.B. 1115, Calabar, Nigeria.
Parasitol Res. 2004 Mar;92(5):361-6. doi: 10.1007/s00436-003-1038-8. Epub 2004 Jan 21.
The ciliate Ichthyophthirius multifiliis is among the most pathogenic parasites of fish maintained in captivity. In the present study, the effects of the crude methanolic extract of leaves of Mucuna pruriens and the petroleum-ether extract of seeds of Carica papaya against I. multifiliis were investigated under in vivo and in vitro conditions. Goldfish (Carassius auratus auratus) infected with the parasites were immersed for 72 h in baths with M. pruriens extract, and for 96 h in baths with C. papaya extract. There was a 90% reduction in numbers of I. multifiliis on fish after treatment in baths of each plant extract at 200 mg l(-1 )compared to untreated controls. Consequently, parasite-induced fish mortality was reduced significantly. A complete interruption of trophont recruitment was achieved by immersion in the M. pruriens extract. In vitro tests led to a 100% mortality of I. multifiliis in 150 mg/l M. pruriens extract, and in 200 mg/l of C. papaya extract after 6 h. Although the active constituents of the medicinal plant extracts are still unknown, we have demonstrated that they have potential for effective control of I. multifiliis.
纤毛虫多子小瓜虫是圈养鱼类中最具致病性的寄生虫之一。在本研究中，对豆科植物刺毛黧豆叶片的甲醇粗提物和番木瓜种子的石油醚提取物在体内和体外条件下对多子小瓜虫的作用进行了研究。将感染寄生虫的金鱼在含有刺毛黧豆提取物的药浴中浸泡72小时，在含有番木瓜提取物的药浴中浸泡96小时。与未处理的对照组相比，在200 mg l(-1)的每种植物提取物药浴中处理后，鱼体上的多子小瓜虫数量减少了90%。因此，寄生虫引起的鱼类死亡率显著降低。通过浸泡在刺毛黧豆提取物中，完全阻断了滋养体的增殖。体外试验表明，在150 mg/l的刺毛黧豆提取物中，6小时后多子小瓜虫的死亡率为100%；在200 mg/l的番木瓜提取物中，6小时后死亡率也为100%。尽管药用植物提取物的活性成分尚不清楚，但我们已经证明它们具有有效控制多子小瓜虫的潜力。
