图们江陆封型马苏大麻哈鱼的个体繁殖力

为研究马苏大麻哈鱼(Oncorhynchus masou)资源保护策略和人工繁殖技术,对人工养殖的图们江陆封型马苏大麻哈鱼繁殖力进行了研究。选取122尾不同养殖区域卵巢发育Ⅳ-Ⅴ期的马苏大麻哈鱼样本(其中延吉42尾、山东35尾、北京45尾)进行统计分析。试验马苏大麻哈鱼体重209~845 g,平均为(512±206)g;体长17.0~39.5 cm,平均为(26.81±6.53)cm。结果表明,大麻哈鱼的绝对繁殖力410~3 075粒,平均为(1 485±797)粒;体重相对繁殖力1.93~3.64粒/g,平均为(2.72±0.47)粒/g;体长相对繁殖力23.60~77.85粒/cm,平均为(51.35±17.60)粒/cm;Ⅴ期卵巢性腺指数14.85%~27.93%,平均为(20.97±3.57)%;繁殖力随着体重、体长、性腺指数增加而提高(P0.01)。通过人工驯养和移植培育,改变了马苏大麻哈鱼在自然环境下雌鱼卵巢发育不成熟的现象,而且繁殖力明显提高。移植到北京和山东后,其繁殖力极显著高于原产地(P0.01)。国产陆封型马苏大麻哈鱼具有规模化人工繁育的优势,能够为野生种群资源增殖提供苗种补充。

Individual Fecundity of Landlocked Oncorhynchus masou in the Tumen River

The fecundity of landlocked Oncorhynchus masou was studied, so that theoretical basis was provided for conservation strategies and artificial breeding technology. By the 122 sample statistics, the average body weight was 512±206g (range from 209g to 845g ), the average absolute fecundity was 1485±797 eggs per fish (range from 410 to 3075 eggs per fish), the average relative fecundity in body weight was 2.72±0.47 eggs per gram ( range from 1.93 to 3.64 eggs per gram), the average relative fecundity in body length was 51.35±17.60 eggs per cm ( range from 23.60to 77.85 eggs per cm), gonadosomatic index was 20.97±3.57% (range from14.85% to 27.93% ). The fecundity were found to be very significantly increased with the increase in body weight, body length, and gonadosomatic index (P<0.01). The fertility of artificial breeding population was significantly higher than the wild population(P<0.01). By domestication and transplantation,Sthe phenomenon of female premature was saved in the natural environment and the fertility was increased. The landlocked Oncorhynchus masou had the advantage of large-scale artificial breeding. The artificial breeding population could complement the wild populations.