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本项目研究池塘养殖的鲩 (草 )鱼体内寄生的头槽绦虫 (B .acheilognathi)的种群动态。于 1 986、1 9 87和 1 998三年内分别观察 0、Ⅰ龄幼鲩及Ⅱ龄商品鲩感染的情况。 0龄及Ⅰ龄越冬鲩的绦虫种群由初染至收敛周期为 1年 ,Ⅱ龄鲩不感染 ,冬季高感染率导致早春水温在 2 0 4℃的感染高峰 ,感染强度持续数月 ,6月达到 2 4 3虫 /鱼。未感染的 0及Ⅰ龄幼鲩在 2、 3月分别引进放养感染了的越冬Ⅰ龄鲩的池塘。1个月后 ,感染率达到 93 1 %～ 96 9% ,8至 9月感染率迅速下降 ,1 0月又稍升高。 1 986和 1 987年的 4～8月 ,绦虫的分布 (S2 / X) >1 ,为聚集分布 ,体长 <1cm的幼虫在种群结构中占优势 ,为 97 2 %～98 2 % ,1 1月幼虫数目下降 ,大孕节绦虫随之出现 ,1 2月大孕节绦虫仅少数存留或全部消失。试验结果为消灭鲩鱼绦虫病提供了可靠依据。
The project is to study the population dynamics of parasitized A. taiwilliatus in the pond-bred (grass) fish. In 1986, 1987 and 1988, respectively, three years of observation, 0, Ⅰ-year-old children and Ⅱ age commercial infection. In the first instar and the first instar larvae, the tapeworm population from the first infection to the convergence period was 1 year, and the second instar larvae were not infected. The high infection rate in winter led to the peak infection in early spring at 204 ℃. The infection intensity lasted for several months. June Reached 2 4 3 insects / fish. Uninfected 0 and 1-year-old larvae were introduced in February and March respectively stocking infected ponds of ichthys nidus. After 1 month, the infection rate reached 93.1% ~ 96.9%. The infection rate declined rapidly from August to September and rose slightly in January-October. The distribution of tapeworms (S2 / X)> 1 between 1 August 1986 and 1987 was congregated, and larvae with body length <1 cm predominated in the population structure, ranging from 97 2% to 98 2% In January, the number of larvae decreased, tapeworm occurred during pregnancy, and females died or disappeared in February. The test results provide a reliable basis for the elimination of catfish taeniasis.