冷泉养殖香鱼试验及其生长特点

在18～22℃冷泉条件下,进行了香鱼养殖试验.平均体重为2.65和0.73 g的两种规格香鱼苗种,经110 d饲养,平均体重分别达76.56和55.88 g;饲料系数分别为1.43和1.32,饲料系数与鱼不同阶段体重呈曲线正相关Y-0.9277-0.0029X＋0.0002X2（R2-0.838,P＜0.01）;香鱼肥满度从投放鱼种（0.73g）时的0.901增加到实验结束时的1.368,肥满度在养殖后半程才开始显著增大,肥满度对体长的最优回归方程为线性方程Y-0.7054 ＋0.0428X （R2-0.505,P＜0.01）.鱼体重对体长的最佳回归模型为指数曲线模型Y-0.3647e （0326X）（R2=0.980,P＜0.01）.运用Bertalanffy、Gompertz和Logistic 3种非线性生长模型分别对香鱼的体重生长数据进行了拟合和分析.3种模型对香鱼体重生长均有很好的拟合度,其中,大、小规格香鱼鱼种生长的Gompertz模型拟合度（R2）分别为1.000和0.999;以该模型测算的生长参数拐点体重分别为43.866和40.014 g,最大日增重分别为0.914和0.781 g,拐点日龄分别在鱼种投放后的第72和89 d.

Growth Characteristics of Cultured Plecoglossus altivelis in Cold Spring

The ayu, Plecogtossus altivelis were reared under temperature 18 -22℃ of coldwater spring. After being fed 110 days, the average body weight of two size juveniles of the ayu from 2.65 and 0.73g reached up to 76.56 and 55.88g respectively. The food coefficients were 1.43 and 1.32 respectively, there were positive relationship between food coefficients and body weights of the ayu, the best regression equation was YyO.9277-O.OO29X＋O.OOO2X2 （R2=-0.838, P〈0.01）. The condi- tion factors of the fish were from 0.901 to 1.368, but that increased slowly in preceding half of the rearing period and increased rapidly in second half of the period. The regression model of condition factor and body length was Y=0.7054＋0.0428X （R2=-0. 505, P〈0.01 ）, and the model of body weight and length of the ayu was Y=0.3647e （0.3267x）（RZ=0.980,P〈0.01 ）.Three kinds of growth model （Bertalanffy, Gompertz and Logistic） were fitted to the growth data on average weight of the ayu, the best-fitting growth model was Gompertz model, that R2 of the model of the two size juveniles of the ayu were 1.000 and 0.999 respective- ly, the points of weight growth inflection were 43.866and 40.014 g, the maximum daily gain were 0.914and 0.781g/d, and the points of age were 72 and 89d, aRer the juveniles of ayu were fed in the coldwater pools, respectively.