凡纳滨对虾全同胞家系的建立及生长比较

全同胞家系是遗传分析的重要材料。采用自然交配法建立了62个凡纳滨对虾第一代全同胞家系，对其中17个家系进行了比较研究。结果表明，各家系的孵化率、出苗率与雌性亲本的大小相关性不显著。17个家系中有7个家系显示生长优势，其大小顺序依次是A02＞A11＞A01＞A17＞A06＞A08＞A16；7个家系在40周内的生长速度较17个家系的平均值高23.2%。在所有家系中，A01、A02、A11等3个家系的体重显著大于其它家系（P＜0.05），其平均生长速度较所有家系平均生长速度分别快25.5%、31.6%和31.0%。这3个家系的整齐度良好，在养殖中期的个体变异系数分别为11.58%、9.95%和8.48%，后期均小于5%，显示出优良的经济性状，为进一步选择培育凡纳滨对虾的快速生长新品系奠定了基础。

Full-sib families construction and their growth comparison of Pacific white leg shrimp, Litopenaeus vannamei

Full-sib family is an important material for genetic analysis. Sixty-two full-sib families of the first generation of Pacific white leg shrimp, Litopenaeus vannamei, are constructed by natural mating and seventeen of them are studied in growth traits. Results indicate no significant correlation of hatchability and survival rate of postlarvae to the weight of female parent. Seven families are significantly faster in growth than others in the 40 weeks of growth traits, and the order of their weight is A02 > A11 > A01 > A17 > A06 > A08 > A16. These seven faster families are 23.2% higher than the mean value of all 17 families in growth rate (g/week) during the 40 weeks traits (P <0. 05). By comparison of each family, families A01, A02 and All are 25.5% , 31.6% and 31. 0% larger than the mean value of the seventeen families respectively. Moreover, these three families display the smaller coefficient of variation (CV), and the CV values in the middle of growth period are 11. 58% , 9.95% and 8.48% respectively. The CV values of the three families are <5% in the later growth period. Therefore the results indicate that they are three families with excellent economic properties. These results are helpful for further selective breeding of fast-growth line of Litopenaeus vannamei.