Abstract:

Siniperca chuatsi is an important high-quality freshwater aquaculture species in China. As a naturally carnivorous and highly predatory fish， it primarily feeds on live bait. Artificial domestication methods to alter the dietary habits of carnivorous fish can reduce farming costs and decrease reliance on natural resources. To investigate the effects of replacing live bait with compound feed on the growth performance， digestive function and antioxidant capacity of S. chuatsi， juvenile S. chuatsi （23.17±0.75 g） were divided into 3 groups： compound feed （F group）， live bait （B group）， a mixed diet of one meal of compound feed and one meal of live bait （M group）. After 3 months of farming， growth performance indicators were measured， digestive and antioxidant enzyme activities were assessed， and the microstructures of the gastrointestinal tract were observed. The results showed that the body weight and body length of F group were significantly higher than those of M group， and the feed conversion ratio of F group was significantly lower than that of B group. However， no significant differences were observed in total length， body height， condition factor， hepatosomatic index， and viscerosomatic index among the 3 groups. The superoxide dismutase activity in F and M groups was significantly higher than that in B group， while the catalase activity in B and M groups was significantly higher than that in F group. The reduced glutathione content and glutathione peroxidase activity in F group were significantly higher than those in M group， and the total antioxidant capacity in B group was significantly higher than that in M group. No significant differences were observed in malondialdehyde content among the 3 groups. In gastric tissues， the trypsin activity in M group was significantly lower than that in B group， while the amylase activity in F group was significantly higher than that in B group. No significant differences were observed in gastric lipase activity and intestinal digestive enzyme activities among the 3 groups. The intestinal villus height in the F group was significantly greater than that in B and M groups. Compared to B group， the intestinal villi in F and M groups were sparser， with increased inter-villus spaces in the intestinal lumen. In conclusion， domesticated S. chuatsi fed with compound feed showed no adverse effects on growth performance， although M group was less effective than the other 2 groups. The fish adapted to the compound feed by enhancing amylase activity， increasing specific antioxidant enzyme activities， and improving intestinal villus height and inter-villus spaces. Above results provided theoretical basis for the large-scale farming of S. chuatsi using formulated feed and further optimization of feed composition.

Key words: Siniperca chuatsi, compound feed, growth performance, digestive function, antioxidant capacity

摘要：

鳜鱼（Siniperca chuatsi）是我国重要的淡水养殖优质鱼类，天生吃活饵，是凶猛的肉食性鱼类。采用人工驯化的方法改变肉食性鱼类的食性可以降低养殖成本并减少对自然资源的依赖。为探究配合饲料替代活饵对翘嘴鳜生长性能、消化功能及抗氧化能力的影响，将驯化的翘嘴鳜幼鱼（23.17±0.75 g）分别饲喂配合饲料（F组）、活饵（B组）、1餐饲料和1餐活饵（M组），养殖3个月后测量其生长指标及消化酶和抗氧化酶活性，并观察胃肠道组织显微结构。结果显示，F组的体质量和体长显著高于M组，F组的饲料系数显著低于B组，全长、体高、肥满度、肝体比和脏体比在3组之间均无显著差异；F组和M组的超氧化物歧化酶活性显著高于B组，B组和M组的过氧化氢酶活性显著高于F组，F组的还原型谷胱甘肽含量、谷胱甘肽过氧化物酶活性显著高于M组，B组的总抗氧化能力显著高于M组，3组之间的丙二醛含量差异不显著。在胃组织中，M组胰蛋白酶活性显著低于B组，F组淀粉酶活性显著高于B组，胃脂肪酶活性和肠道消化酶活性在3组间差异不显著；F组肠道绒毛高度显著高于B组和M组，相比B组，F组和M组肠道绒毛较稀疏，肠腔中绒毛间空隙增大。综上，翘嘴鳜经过驯化后摄食配合饲料不会影响其生长性能，但M组的饲喂效果不及另外2组。鱼体通过提高淀粉酶活性和部分抗氧化酶活性，以及增加肠道绒毛高度和绒毛间空隙，对饲料养殖具有一定的适应性。研究结果为鳜鱼的大规模饲料养殖以及饲料成分的进一步优化提供了理论依据。

关键词: 翘嘴鳜, 配合饲料, 生长性能, 消化功能, 抗氧化能力