饲料浮萍水平对黄金锦鲤生长性能、消化酶活力及抗氧化能力的影响

摘要

Koi carp Cyprinus carpio with initial body weight of (52. 99±1. 95)g was reared in net cages at a density of 30 fish per cage and fed six isonitrogenous (38. 5%-38. 6%, crude protein) and isocaloric (12. 2 MJ/kg) diets containing 0(control,D1), 3% (D2), 6% (D3), 9% (D4), 13 % (D5), and 14% (D6) dry duckweed meal replacing corresponding rapeseed meal at water temperature of (29. 0±1. 1)℃ or 8 weeks with triplication to evalu-ate the effects of dietary duckweed levels on growth, antioxidant ability, and digestive ability of koi carp. The re-sults showed that there were significantly higher weight gain rate( WGR) , specific growth rate( SGR) , protein effi-cient ratio( PER) and condition factor( CF) and significantly lower food conversion ratio ( FCR) in the fish in group D6 than those in the control group and in group D2 ( P<0 . 05 ) . The koi carp fed the diet containing 14% duck-weed had significantly higher activities of protease and lipase than the fish in other groups did(P<0. 05), without significant differences in amylase activity ( P>0 . 05 ) . There were significantly higher activities of superoxide dis-mutase( SOD) and catalase( CAT) in hepatopancreas, kidney, spleen and serum in the fish fed the diets containing 9% and 14% duckweed meal than those in the other groups ( P<0 . 05 ) , with significantly lower contents of malon-dialdehyde (MDA) in the fish fed the diets containing 14% duckweed (P<0. 05). The findings indicate that sup-plementation of 14% duckweed replacing corresponding rapeseed meal can improve the growth, and meet require-ments for antioxidant ability and digestive capacity of koi carp.%为研究浮萍Lemna minor对黄金锦鲤Cyprinus carpio生长性能、 抗氧化和消化能力的影响,以初始体质量为(52.99±1.95)g的黄金锦鲤为研究对象,在饲料中分别添加0、3%、6%、9%、13%、14%的浮萍,相应替代同等水平的菜粕,制成6组等氮(粗蛋白质为38.5%~38.6%)、 等能(12.2 MJ/kg)的饲料,分别记为D1(对照)、D2、D3、D4、D5、D6饲料组,将540尾健康的黄金锦鲤随机分成6组,每组设3个重复,每个重复放30尾鱼,养殖时间为8周.结果表明:D6饲料组增重率(WGR)、 蛋白质效率(PER)、 特定生长率(SGR)和肥满度(CF)均显著高于对照组及添加水平为3%的饲料组(P<0.05),而其饲料系数(FCR)显著低于上述两组(P<0.05);D6饲料组蛋白酶活力与脂肪酶活力显著高于其他饲料组(P<0.05),各饲料组间淀粉酶活力则无显著性差异(P>0.05);D4与D6饲料组肝胰脏、 脾脏、 肾脏和血清中的超氧化物歧化酶(SOD)与过氧化氢酶(CAT)活力显著高于其他饲料组(P<0.05),且D6饲料组丙二醛(MDA)活力显著最低(P<0.05).研究表明:本试验条件下,饲料中浮萍的添加水平在14%时,有利于黄金锦鲤的生长,并能提高鱼体抗氧化能力与消化酶活力.