饵料对鱼类生长发育和繁殖具有重要影响。为了筛选稀有鲫(Gobiocypris rarus)幼鱼和成鱼阶段最适投喂方式,实验将出膜5周末(日龄为35 day after hatching)的幼鱼随机分为5个组:A组投喂丰年虫;B组每周前6d(days)投喂丰年虫,后1d投喂商...饵料对鱼类生长发育和繁殖具有重要影响。为了筛选稀有鲫(Gobiocypris rarus)幼鱼和成鱼阶段最适投喂方式,实验将出膜5周末(日龄为35 day after hatching)的幼鱼随机分为5个组:A组投喂丰年虫;B组每周前6d(days)投喂丰年虫,后1d投喂商业化微颗粒S3饲料;C组每周前3.5d投喂丰年虫,后3.5d投喂饲料;D组每周前1d投喂丰年虫,后6d投喂饲料;E组一直投喂饲料;各组均采用饱食投喂策略。每2周统计生长、存活指标,直至第21周(147 dah),在17周(119 dah)取材用于观察性腺发育程度。在产卵后统计各组产卵量、孵化率和子代畸形率。结果显示:(1)E组存活率和特定生长率显著低于其他组(P<0.05);(2)从产卵量、孵化率和子代畸形率上看,B组产卵量显著高于其他组(P<0.05);(3)从性腺组织学上看,不同投喂方法对精巢的成熟度无显著影响,但投喂过丰年虫的稀有鲫卵巢发育成熟度显著优于E组。研究结果提示:适量加入丰年虫比单一投喂活饵或饲料更有利于稀有鲫的生长和繁殖。建议在标准化养殖过程中,幼鱼和成鱼期的稀有鲫采取丰年虫与饲料投喂频次比值为6﹕1的方式最佳。展开更多
An 8-week feeding trial was conducted to detect the optimal dietary protein and energy, as well as the ef fects of protein to energy ratio on growth, for the rare minnow( Gobiocypris rarus), which are critical to nutr...An 8-week feeding trial was conducted to detect the optimal dietary protein and energy, as well as the ef fects of protein to energy ratio on growth, for the rare minnow( Gobiocypris rarus), which are critical to nutrition standardization for model fi sh. Twenty-four diets were formulated to contain three gross energy(10, 12.5, 15 kJ/g), four protein(20%, 25%, 30%, 35%), and two lipid levels(3%, 6%). The results showed that optimal dietary E/P was 41.7–50 kJ/g for maximum growth in juvenile rare minnows at 6% dietary crude lipid. At 3% dietary lipid, specifi c growth rate(SGR) increased markedly when E/P decreased from 62.5 kJ/g to 35.7 kJ/g and gross energy was 12.5 kJ/g, and from 75 kJ/g to 42.9 kJ/g when gross energy was 15.0 kJ/g. The optimal gross energy was estimated at 12.5 kJ /g and excess energy decreased food intake and growth. Dietary lipid exhibited an apparent protein-sparing eff ect. Optimal protein decreased from 35% to 25%–30% with an increase in dietary lipid from 3% to 6% without adversely ef fecting growth. Dietary lipid level af fects the optimal dietary E/P ratio. In conclusion, recommended dietary protein and energy for rare minnow are 20%–35% and 10–12.5 k J/g, respectively.展开更多
文摘饵料对鱼类生长发育和繁殖具有重要影响。为了筛选稀有鲫(Gobiocypris rarus)幼鱼和成鱼阶段最适投喂方式,实验将出膜5周末(日龄为35 day after hatching)的幼鱼随机分为5个组:A组投喂丰年虫;B组每周前6d(days)投喂丰年虫,后1d投喂商业化微颗粒S3饲料;C组每周前3.5d投喂丰年虫,后3.5d投喂饲料;D组每周前1d投喂丰年虫,后6d投喂饲料;E组一直投喂饲料;各组均采用饱食投喂策略。每2周统计生长、存活指标,直至第21周(147 dah),在17周(119 dah)取材用于观察性腺发育程度。在产卵后统计各组产卵量、孵化率和子代畸形率。结果显示:(1)E组存活率和特定生长率显著低于其他组(P<0.05);(2)从产卵量、孵化率和子代畸形率上看,B组产卵量显著高于其他组(P<0.05);(3)从性腺组织学上看,不同投喂方法对精巢的成熟度无显著影响,但投喂过丰年虫的稀有鲫卵巢发育成熟度显著优于E组。研究结果提示:适量加入丰年虫比单一投喂活饵或饲料更有利于稀有鲫的生长和繁殖。建议在标准化养殖过程中,幼鱼和成鱼期的稀有鲫采取丰年虫与饲料投喂频次比值为6﹕1的方式最佳。
基金Supported by the National Key Technology R&D Program of China(No.2011BAI15B01-41)the National High Technology Research and Development Program of China(863 Program)(No.2012AA06A302)
文摘An 8-week feeding trial was conducted to detect the optimal dietary protein and energy, as well as the ef fects of protein to energy ratio on growth, for the rare minnow( Gobiocypris rarus), which are critical to nutrition standardization for model fi sh. Twenty-four diets were formulated to contain three gross energy(10, 12.5, 15 kJ/g), four protein(20%, 25%, 30%, 35%), and two lipid levels(3%, 6%). The results showed that optimal dietary E/P was 41.7–50 kJ/g for maximum growth in juvenile rare minnows at 6% dietary crude lipid. At 3% dietary lipid, specifi c growth rate(SGR) increased markedly when E/P decreased from 62.5 kJ/g to 35.7 kJ/g and gross energy was 12.5 kJ/g, and from 75 kJ/g to 42.9 kJ/g when gross energy was 15.0 kJ/g. The optimal gross energy was estimated at 12.5 kJ /g and excess energy decreased food intake and growth. Dietary lipid exhibited an apparent protein-sparing eff ect. Optimal protein decreased from 35% to 25%–30% with an increase in dietary lipid from 3% to 6% without adversely ef fecting growth. Dietary lipid level af fects the optimal dietary E/P ratio. In conclusion, recommended dietary protein and energy for rare minnow are 20%–35% and 10–12.5 k J/g, respectively.
