三种投喂模式对河蟹二龄成蟹养殖性能的影响

比较了池塘养殖条件下,全程投喂配合饲料、杂鱼和传统饵料(以黄豆、小麦和玉米为主,辅以少量饲料和杂鱼)对河蟹(Eriocheir sinensis)二龄成蟹生长、性腺发育、规格分布、成活率、单产、饵料系数和饵料成本的影响。结果显示:(1)无论雌雄,传统饵料组早期(5-8月份)的增重率和特定生长率方面最低,杂鱼组最高;(2)杂鱼组雌体8月份性腺发育速度最快,传统饵料组性腺发育速度最慢,其余月份雌体和雄体的性腺指数和肝胰腺指数均无显著差异;(3)无论雌雄,最终杂鱼组的大规格成蟹(雄体175 g,雌体100 g)比例最高,而传统饵料组的小规格成蟹(雄体100 g,雌体75 g)比例最高,且体重差异较大,配合饲料组的中等规格成蟹较为集中,最终三组投喂模式下雌雄蟹的平均体重并无显著差异,杂鱼组略大于传统饵料组;(4)三种投喂模式下,三者的成活率和平均产量并无显著差异;杂鱼组的饵料系数和饵料成本最高,配合饲料组饵料系数最低,但饵料成本居中;传统饵料组饵料系数居中,饵料成本最低。结果表明,全程投喂配合饲料对河蟹二龄成蟹的养殖性能和性腺发育无显著影响。

Effects of three feeding modes on the culture performance of adult pond -reared Chinese mitten crab (Eriocheir sinensis) during the second year culture

This study was conducted to investigate the effects of three feeding modes (i.e.feeding with formulated diet;feeding with trash fish; feeding with traditional mixture feeds , including soybeans, wheat, broad bean and corn, small a-mount of trash fish and formulated diets ) on growth, gonad development, size distribution, final survival, crab yield, feed conversion rate (FCR) and feed cost per kg crabs of cultured Eriocheir sinensis.The result showed that: (1) despite of the gender, the traditional mixture feeds treatment (TMF) had the lowest weight gain rate (WGR) and the specific growth rate (SGR) during the early period (May -August), while the trash fish treatment (TF) had the highest WGR and SGR among three treatments; (2) in most cases, there were no significant differences for the gonadsomatic index (GSI) and the hepatosomatic index (HSI) among three feeding modes.However, the females of TF had the highest GSI , while the TMF had the lowest GSI in the August ; (3) by the end of the experiment, regardless of the gender, trash fish treatment had the highest proportion of large -sized adult crab (male >175 g, female >100 g), whereas the traditional feed treatment had the highest percentage of small -sized adult crab (male <100 g, female <75 g) and the large size differences were found in this treatment.Most of crabs from formulated diet treatment were medium -sized.There were no significant differences for final mean body weight among the three feeding modes , and final body weight of trash fish treat -ment was slightly larger than that of traditional feed treatment ; (4) although there were no significant effects on the surviv -al rate and the crab yield per square meter , the TF had the highest FCR, and the formulated diet treatment had the lowest FCR.As for the feed cost of adult crab per kilogram , the cost turn was shown as trash fish treatment >formulated diet treat-ment >traditional feed treatment.Therefore, feeding formulated diet had no significantly negative effects on culture perform -ance and gonad development of adult E.sinensis during the whole culture process.