凡纳滨对虾家系淡水耐受性状与生长性状的关系

The relationship between tolerance to fresh water and growth traits for desalination culture in families of Pacific white leg shrimp,Litopenaeus vannamei

本研究对亲本来自不同遗传背景的10个凡纳滨对虾家系进行了淡水应激试验和淡化培育试验,分别测定了其淡水应激存活率和淡化培育过程中的各项生长性状指标,并研究了凡纳滨对虾家系淡水耐受性与其淡化培育过程中生长性状的关系。结果显示:1)10个凡纳滨对虾家系淡水应激存活率存在极显著差异(p<0.01),由高到低为TF-1(68%)>DG-1(58%)>HX-2(56%)>SD-1(50.5%)>TF-2(38%)=DG-2(38%)>DF-1(35%)>SD-2(34%)>DF-2(33%)>HX-1(27%);2)淡化培育过程中,10个凡纳滨对虾家系之间的淡化培育存活率由高到低为TF-1(51%)>SD-1(44%)>DG-1(40%)>TF-2(36%)>HX-2(29%)>SD-2(25%)>DG-2(20%)>DF-2(17%)>DF-1(16%)>HX-1(13%),存在极显著差异(p<0.01),体重增长率、特定生长率和体长增长率10个家系之间存在显著性差异(p<0.05),而且不同家系的饵料系数之间也存在显著性差异(p<0.05);3)获得的家系TF-1的淡水应激存活率(68%)、淡化培育存活率(51%)、体重增长率(17.54mg·d–1)、特定生长率(6.68)和体长增长率(0.53mm·d–1)都高于其他家系,饵料系数(0.82)与其他家系相比则最低;4)淡水应激存活率与淡化培育存活率及体长增长率存在极显著的相关性(r>0.8,p<0.01),与平均增重率、特定生长率、饵料系数存在一定的相关性(0.5<|r|<0.8,p<0.05)。研究表明:凡纳滨对虾仔虾的淡水应激存活率反映了虾苗的耐淡能力,可作为选择淡化培育用虾苗的一个重要指标;家系TF-1为进一步选育出耐淡能力更强和生长更快的新品系提供了基础。

Previous investigations have shown that the rate of crustacean survival in salinity stress test was strongly relative to their future growth. In this research, a freshwater stress test followed with desalination culture experiment was carried out on 10 families of Pacific white leg shrimp, Litopenaeus vannamei, in the same batch with different genetic backgrounds. The freshwater stress survival rate and desalination culture growth traits in different families were determined;at the same time the relationship between them was also analyzed. Our study indicated that there was a significant difference （p〈0.01） among survival rates under freshwater stress of the 10 families. During the desalination culture, the survival rates of the 10 families were significantly different （p〈0.01）;there were differences （p〈0.05） among body weight growth rate, the specific growth rate, body length growth rate, and feed coefficient of the 10 families performance. The family TF-1 had the highest survival rate under freshwater stress （63%） and desalination culture （51%）, as well as body weight growth rate （17.54 mg·d-1）, specificgrowth rate （6.68）, and body length growth rate （0.53 mm·d-1）; however, its feed coefficient （0.82） was lower than the other families. The survival rate under freshwater stress was positively correlated to desalination culture survival rate （r=0.855, p〈0.01）, body weight growth rate （r=0.636, p〈0.05）, specific growth rate （r=0.617, p〈0.05）, and body length growth rate （r=0.805, p〈0.01）, while it had a negative correlation with feed coefficient （r=-0.748, p〈0.05）. The research showed that survival rate of the shrimp postlarvae to freshwater stress test could represent the postlarvae’s quality on tolerance to fresh water, which will be an important reference index among the L. vannamei postlarvae’s desalination culture. Meanwhile, the family TF-1 would be used to breed high freshwater tolerance and fast-growing variety of L. vannamei.