内外因素对凡纳滨对虾仔虾同类相残的影响

Effects of Internal and External Factors on Cannibalism in Post-larvae of Litopenaeus vannamei

为了解凡纳滨对虾(Litopenaeus vanname)仔虾同类相残行为,分析了个体规格、幼体密度、饵料丰度、充气4个内、外因素对其同类相残的影响。结果表明,幼体密度、饵料丰度、个体规格显著影响凡纳滨对虾的同类相残率。当幼体密度从50 ind/L提高到120 ind/L时,平均日相残率升高190%;当幼体密度大于120 ind/L时,平均日相残率增加幅度相对较小。饵料密度20 ind/m L组与不投喂组相比,平均日相残率降低78.5%。不同个体规格仔虾混养时,对虾的平均日残率显著高于单养组。高充气量组,相残率下降。可见,饵料缺乏可能是导致仔虾同类相残的主要原因,高放养密度和个体规格差异等因素会诱发和促进同类相残的发生。

In order to study the effects of internal and external factors on cannibalism in post-larvae of Litopenaeus vannamei,four factors were conducted,including individual size,larvae density（ 50,80,120,140,160 ind / L）,food abundance,aeration condition. The results showed that the cannibalism rate was significantly effected by individual size,larvae density and food abundance. When larval density increased from 50 ind / L to 120 ind / L,the average dalily cannibalism rate increased by 190%. When larval density was more than 120 ind / L,cannibalism rate increased relatively little. The average daliy cannibalism rate decreased by 78. 5% in 20 ind / m L food group than that of no-food group. The mix of individuals in different sizes could increase cannibalism rate significantly. Sufficient aeration could decrease cannibalism rate. The results indicated that insufficient food was a main reason to cause cannibalism in Litopenaeus vannamei post-larvae. High stocking density and differences of individual size could induce and stimulate cannibalism.