凡纳滨对虾7个引进群体的生长性能评估

Evaluation of growth performance in Litopenaeus vannamei populations introduced from other nations

为了对凡纳滨对虾7个引进群体的生长性能进行评估,通过巢式交配和人工授精的方式,用2011年源自不同国家和地区的7个凡纳滨对虾群体建立了130个全同胞家系,包括17个杂交组合(正反交合并)和7个自交组合。各家系的仔虾、幼虾经中间暂养和标记后混合,在河北黄骅(HBHH)和青岛鳌山(QDAS)两个养殖场养殖,测定了153日龄虾体质量性状。用混合线性模型估计不同群体和家系体质量最小二乘均值,计算不同杂交组合杂种优势率,评估不同群体和杂交组合的生长性能。结果表明,凡纳滨对虾各群体体质量变异系数变化范围为13%～26%;UA5、UA4和SIN三个群体为亲本的153日龄虾体质量最小二乘均值均较高,分别比群体均值高5.34%、2.51%和1.67%,是体质量性状育种的优良亲本;杂交组合均值(18.14 g)比自交组合(17.17 g)高5.65%,杂交组合UA4×UA5体质量最小二乘均值最高(19.52 g),比杂交组合均值高7.61%;组合杂种优势率在-1.77%～11.72%,均值为5.45%,大部分杂交组合(>75%)存在正向杂种优势,UA1×UA2杂交组合杂种优势率最高。研究结果有助于提高凡纳滨对虾生长性能遗传选择的准确性,并为实现良种选育奠定基础。

In 2011,seven batches of Litopenaeus vannamei,introduced from America and Singapore were collected to evaluate the growth performance.The nest design was adopted and 130 full-sib families（17 hybridized combinations and 7 inbred combinations）were obtained by artificial insemination.Offspring of the 130 families were cultured separately through the larval and juvenile stages,and were fluorescence-tagged when they reached a body length of 3 cm.The shrimps were tagged with a unique family code by injecting different colours of ＂Visible Implant Fluorescent Elastomers＂（VIE）before being stocked in one grow-out pond.All families were randomly divided into two groups and then cultured in both Huanghua,Hebei and Aoshan,Qingdao,simultaneously.Body weight（g）of these shrimps was measured after 153 d.Growth performance of every population and combination was evaluated by analyzing the least squares means（LSM）and heterosis for body weight in L.vannamei.The results showed that,on the 153rd day,the variation coefficient of body weight of the L.vannamei stocks was 13%-26%.The LSM for body weight of the UA5 batch,UA4 batch and SIN batch were higher than average by 5.34%,2.51% and 1.67%,respectively.So these 3 batches could be used as parents for high quality cultivars.A growth performance analysis showed the average LSM of hybridized combination（18.14 g）was higher than the average LSM of inbred combinations（17.17 g）.The highest LSM occurred in the cross between the UA4 batch and the UA5 batch,with 7.61 percent higher than average.Heterosis analysis showed,they ranged from a low of-1.77% to a high of 11.72%,with a mean of 5.45%,positive heterotic vigor was detected in most hybridized combination.The highest heterosis occurred in the cross between the UA1 batch and the UA2 batch.Our study provides insight into methods for improving the accuracy of genetic selection for growth traits in L.vannamei,and for genetics and breeding research into quantitative traits in other aquatic animals.