卡特拉鱼形态、食性和生长的研究
STUDIES ON THE MORPHOLOGY,FEEDING HABIT AND GROWTH OF CATLA CATLA
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摘要: 观测卡特拉鱼的形态特征和1—3龄鱼主要可量性状及其比例的变动。1—3龄鱼除主食商品饲料外,同时也食较大比例的浮游生物。着重对浮游生物的种类和比例进行了分析。肠长与体长呈直线相关。Y=6.38X-89.95。1—4龄鱼体长和体重相对生长率和生长指标都随年龄增加而逐渐下降。体长与体重呈曲线相关。W=0.00002261L3.0569。采用 Von.Bertalanffy 生长方程分析其生长特性。方程参数 L∞=821.2mm,W∞=19616.6g,t0=0.6年,K=0.3。体长生长不具拐点,生长速度随年龄增加而递减;体重生长具拐点,其值4.3年。此时体重生长速度达最大值。4、3龄前是生长旺盛期,此后进入生长缓慢期。Abstract: This paper describes the morphology and changes in the major measurable characters and their ratios in 1—3 year-old Catla carla.1—3 year-old fish feed chiefly on artificial food,they also eat a large part of plankton.The taxes and ratios of plankton have been analysed.There existed a linear correlation between intestine length(Y)and body length(X): Y=6.38X-89.95. Relative growth rates and growth index in body length and body weight decreased gradually with increases in age over the range of 1—4 years.The relationship between body length(L)and body weight(W)was:W=0.00002261L3.0669.The characters of growth were analysed using Von.Bertalanffy growth equation.The estimated parameters were:L∞=821.2 mm;W∞=19616.6g;t0=0.6year;k=0.3.There was no turning point in the growth of body length.The growth rate decreased gradually with increased age.In the growth of body weight, a turning point was found at the age of 4.3 years,at which the weight growth rate reached the maximum.The fish exhibited rapid weight growth before the age of 4.3 years;afterwords, weight growth slowed down.