池养条件下1龄异育银鲫“中科3号”的生长特性

Growth characteristics of one-year-old Carassius auratus gibelio“CAS Ⅲ” cultured in ponds

摘要:

为了解池塘养殖条件下1龄异育银鲫“中科3号”的生长特性,在池塘自然水温(18.5～30.6 ℃)条件下,对体长(4.53±0.18)cm、体质量(2.73±0.17)g的1龄异育银鲫“中科3号”的生长性能进行了研究。试验结果:经过125 d培育,异育银鲫“中科3号”体长增长237.53%,体质量增长3 312.45%；体长与体质量呈幂函数关系,关系式为W=0.035 6L2.888 5(R²=0.985),属等速生长型；体质量日增长量从试验开始到100 d始终呈增高态势,75～100 d的平均体质量日增长量为最高值(1.346 g/d),之后随着水温下降而降低；体质量相对增长率在0~25 d为最高(269.60%),而后逐渐降低,至125 d试验结束时为30.37%；生长指数(0.105 4～0.464 7)和生长常数(1.318～5.809)随着试验的进行逐渐降低；肥满度为2.606 2～2.948 0 g/cm³,呈先降低、后升高、再降低的小幅波动；生长离散逐渐小幅增加。

Abstract:

For the purpose of understanding growth characteristics of Carassius auratus gibelio “CAS Ⅲ”,the growth performance of one-year-old “CAS Ⅲ” with(4.53±0.18)cm of initial body length and(2.73±0.17)g of initial body weight was studied under pond-culture condition with nature water temperature(18.5~30.6 ℃).After 125 days of rearing,the average body length and body weight of the fish increased by 237.53% and 3 312.45%,respectively.The regression equation of body weight(W)against body length(L)was shown as a power function:W=0.035 6L2.888 5(R²=0.985),which was a type of constant growth.The daily gain of “CAS Ⅲ” increased in first 100 days of rearing and the highest value(1.346 g/d)was observed in the 75~100 d period,but they showed a decreased trend with water temperature decreasing.The relative growth rate of body weight showed a decreasing trend from 269.60% to 30.37% throughout the outdoor culture experiment,and the growth index and growth constant gradually decreased from 0.464 7 to 0.105 4 and 5.809 to 1.318,respectively.Condition factor had a small fluctuation of down-up-down with the range from 2.606 2 g/cm³ to 2.948 0 g/cm³,and the growth dispersion showed a slight increasing trend.