加州鲈冬季适宜投喂频率的研究

Suitable feeding strategy of Largemouth bass in winter

选取平均体重(179.1±0.9)g的加州鲈300尾,随机分配到15个体积为500 L的循环水玻璃钢养殖桶中,试验分5组,每组3个重复,每个重复2 0尾鱼,以不同的投喂频率(两天1次、一天1次、一天2次,均为饱食投喂)和投喂水平(一天1次100%饱食、一天1次75%饱食、一天1次50%饱食)持续投喂60 d,另在体积为10 m^3的水泥池按足量饱食投喂进行胃排空时间测试,同时每间隔11h记录水体溶解氧的变化,探讨了不同的投喂策略对加州鲈生长、形体和肝脏营养成分的影响结果表明:不同投喂策略对加州鲈的摄食量、增重、饲料系数、形体指标以及肝脏水分、粗蛋白、粗脂肪、粗灰分和正常肝比例均存在影响。胃排空时间曲线和溶解氧曲线显示在该条件下加州鲈完全消化饲料所需要的时间为20 h左右。综合认为:在水温17~20℃条件下,179~260 g加州鲈适宜的投喂频率为一天1次,适宜投喂水平为饱食投喂,胃排空时间和水体溶解氧的变化规律可作为制定适宜投喂策略的参考。

The 300 tail [average weight （179.1±0.9） g] Largemouth bass were randomly assigned to 15 volume of circulating water tanks glass steel 500 L. The fish were divided into 5 groups with 3 replicates, each repeated 20 fish with different feeding frequency （two days 1 meal, 1 meal a day and 2 meals a day to satiation feeding） and feeding level （1 meal a day, 1 meal a day with 100%, 75% with 1 meal a day 50% satiation） feeding 60 days continuously. The other in the volume of 10 m3 cement pool according to the sufficient satiation feeding test of gastric emptying time at the same time every 1 h recording of dissolved oxygen change. The experiment discusses the investment strategies of feeding effect on growth, body and liver nutrition of different Largemouth bass. The results show that the differ- ent feeding strategies on feed intake, weight gain and feed coefficient, body index and liver moisture, crude protein, crude fat, crude ash and normal liver ratio have effects. Gastric emptying time curve and dissolved oxygen curve showed that under this condition, the time required for complete digestion of Largemouth bass was about 20 h. Considering all the indexes, under the water temperature 17- 20 ℃, 179-260 g Largemouth bass suitable feeding frequency was l meal a day, the suitable feeding level of satiation feeding, changes of gastric emptying time and dissolved oxygen can be used as reference to establish appropriate feeding strategy.