长江上游长鳍吻鮈Rhinogobio ventralis的个体繁殖力

2012~2015年在长江上游宜宾江段采集样品,分析研究长鳍吻鮈Rhinogobio ventralis的个体繁殖力及其与各体征指标的关系。结果表明:长鳍吻鮈的绝对繁殖力(F)变动范围为16 399~40 021粒/尾,平均为(27 943±7 777)粒/尾;体长相对繁殖力(FL)变动范围为87~165粒/mm,平均为(120.9±19.8)粒/mm;体质量相对繁殖力(FW)变动范围为124~234粒/g,平均为(163.8±21.7)粒/g。繁殖力与体征指标的相关分析表明:F、FL与体长、体质量、净体质量、卵巢质量以及年龄均呈正相关,达到极显著水平(P0.01);FW仅与体质量、净体质量以及成熟系数显著相关(P0.01);进一步回归分析显示:F、FL与体长、体质量、净体质量均呈二次函数相关,即繁殖力随体长、体质量增加而增长。

Individual Fecundity of Rhinogobio ventralis in Upper Stream of the Yangtze River

The individual fecundities and the correlations between individual fecundity and main physical characters were studied in the samples of Rhinogobio ventralis collected from Yibin section of upper Yangtze River from 2012 to 2015. The individual absolute fecundity( F) was found to be varied from 16 399 to 40 021 eggs, an average( 27 943 ±7 777) eggs, the individual relative fecundity ( FL) from 87 to 165 eggs/mm, an average( 120.9 ±19.8) eggs/mm, and Fw from 124 to 234 eggs/g, an average( 163.8 ± 21.7) eggs/g. The correlation analysis revealed that there were very significant positive correlation between F or FL and standard length, body weight, dressed body weight, ovary weight and age ( P < 0.01), while Fw was significantly related with body weight, dressed body weight and gonado-somatic index ( GSI) ( P < 0.01). The regression analysis indicated that the relation between F, FL and standard length, body weight, dressed body weight was expressed in quadratic function equation, increasing with the increase in standard length and body weight.