高棉籽粕饲料中补充赖氨酸和铁对青鱼幼鱼生长、免疫力及组织中游离棉酚含量的影响

Effects of High Cottonseed Meal Diet Supplemented with Lysine and Iron on Growth,Immunity and Tissue Free Gossypol Content of Juvenile Black Carp( Mylopharyngodon piceus)

以初始平均体重为(7.01±0.05)g的青鱼为研究对象,配制5种等氮等能的试验饲料,以含40%豆粕的饲料作为豆粕对照饲料,含41%棉籽粕的饲料作为高棉籽粕饲料,并在高棉籽粕饲料中分别用0.342%的晶体赖氨酸(有效含量79%)、0.115%的七水硫酸亚铁以及0.342%的晶体赖氨酸+0.115%的七水硫酸亚铁等量替代面粉,以研究高棉籽粕饲料中补充赖氨酸和铁对青鱼幼鱼生长、免疫力及组织中游离棉酚含量的影响。每组设3个重复,每个重复30尾,试验期为8周。结果表明:与豆粕对照组相比,高棉籽粕组青鱼的特定生长率、血液红细胞数量以及血清补体4含量和总超氧化物歧化酶、溶菌酶活力均显著降低(P<0.05),血清谷草转氨酶和谷丙转氨酶活力显著升高(P<0.05),同时肝脏游离棉酚累积,但在高棉籽粕饲料中同时补充铁与赖氨酸可显著提高青鱼的特定生长率和血液红细胞数量(P<0.05),并与豆粕对照组差异不显著(P>0.05)。此外,高棉籽粕饲料中补充铁可显著提高青鱼血清补体4含量(P<0.05),补充赖氨酸或铁可显著提高血清溶菌酶活力(P<0.05)并显著降低血清谷草转氨酶和谷丙转氨酶活力(P<0.05),且单一补充铁时血清谷草转氨酶和谷丙转氨酶活力与豆粕对照组无显著差异(P>0.05)。高棉籽粕饲料中补充铁可显著降低肌肉和肝脏中游离棉酚含量(P<0.05),补充赖氨酸可显著升高血清中总超氧化物歧化酶活力(P<0.05)。由结果可知,高棉籽粕饲料中补充铁和赖氨酸能促进青鱼幼鱼的生长,提高机体免疫力,降低肌肉和肝脏中游离棉酚含量,同时补充铁和赖氨酸效果更明显。

An 8-week feeding trial was conducted to evaluate the effects of high cottonseed meal diet supplemented with lysine and iron on growth,immunity and tissue free gossypol content of juvenile black carp [initial average body weight of（ 7. 01 ± 0. 05） g]. Five iso-nitrogenous and iso-energetic experimental diets were formulated,one diet contained 40% soybean meal（ SBM） as the SBMcontrol diet,one diet contained 41%cottonseed meal（ CSM） as high CSMdiet,and the other 3 diets supplemented with 0.342% crystalline lysine（ effective content was 79%）,0.115% Fe SO4·7H2O,0.342% crystalline lysine ＋ 0.115% Fe SO4·7H2O to replace equivalent wheat flour on the basis of high CSMdiet,respectively. Each group had 3 replicates and each replicate had 30 fish. The results showed as follows： compared with SBMcontrol group,the specific growth rate（ SGR）,red blood cell（ RBC） count,serum complement 4（ C4） content and serum total superoxide dismutase（ T-SOD） and lysozyme（ LZM） activities in high CSMgroup were significantly reduced（ P0.05）,serum glutamic-oxaloacetic aminotransferase（ GOP） and glutamic pyruvic transaminase（ GTP） activities in high CSMgroup were significantly increased（ P〈 0.05）,and the free gossypol was accumulated in liver. But,co-supplementation with lysine and iron could significantly increase the SGR and RBC count（ P〈 0.05）,and had no significant differences compared with SBMcontrol group（ P〉 0. 05）. Moreover,supplementation with iron could significantly increase serum C4 content,supplementation with lysine or iron could significantly increase serum LZMactivity and significantly decrease serum GOP and GTP activities（ P〈 0.05）,and there were no significant differences in serum GOP and GTP activities between single supplementation with iron group and SBMcontrol group（ P〉 0. 05）. High CSMdiet supplemened with iron could significantly decrease free gossypol content in muscle and liver（ P〈 0. 05）,and supplemened with lysine could significantly increase serum T-SOD activity（ P〈 0.05）. To conclude,high CSMdiet supplemented with lysine and iron can promote growth,enhance immunity and reduce free gossypol content in muscle and liver,while it is more efficient to be supplemented with lysine and iron simultaneously.