壳寡糖对异育银鲫生长性能、肠道组织结构和非特异性免疫功能的影响

Effects of Chitosan Oligosaccharide on Growth Performance,Intestinal Structure and Non-Specific Immune Function of Crucian Carp( Carassius auratus gibelio)

本试验旨在研究壳寡糖(COS)对异育银鲫生长性能、肠道组织结构及非特异性免疫功能的影响。在含正常豆油、氧化豆油的基础饲料中分别添加0、0.02%、0.04%、0.06%的COS,共配制成8种试验饲料(CG、OO、CG-200、CG-400、CG-600、OO-200、OO-400、OO-600)。其中,以油脂原料为豆油的未添加COS的饲料(CG)作为正对照组,以油脂原料为氧化豆油的未添加COS的饲料(OO)作为负对照组。将初始体重为(7.60±0.05) g的960尾异育银鲫随机分成8组,每组设3个重复(网箱),每个重复40尾鱼,在池塘网箱中养殖72 d。结果显示:与CG组相比,CG-200组的特定生长率(SGR)升高了16.20%(P<0.05),CG-400和CG-600组则无显著变化(P>0.05); CG-200组肠皱襞高度增加了86.84%(P <0.05),肠壁厚度增加了20.45%(P <0.05),肠皱襞宽度减少了12. 18%(P> 0. 05),血清超氧化物歧化酶(SOD)活性上升了6. 59%(P>0.05),血清丙二醛(MDA)含量下降了16.94%(P>0.05); OO组SGR下降了8.10%(P <0.05),肠皱襞高度降低了17.81%(P<0.05),肠皱襞宽度增加了70.37%(P <0.05),肠壁厚度减少了30.33%(P>0.05),血清SOD活性下降了27.35%(P<0.05),血清MDA含量上升了25.72%(P<0.05)。与OO组比,OO-200、OO-400、OO-600组SGR升高不显著(P>0.05),其中OO-400组肠皱襞高度增加了18.89%(P<0.05),肠皱襞宽度降低了42.99%(P<0.05),肠壁厚度增加了38.35%(P>0.05),血清SOD活性上升了40.90%(P<0.05),血清M DA含量下降了16.20%(P>0.05)。OO-400组在SGR、肠道结构、血清SOD活性及M DA含量等指标上达到了与CG组相同的水平。本试验条件下,根据结果得出:在含4%豆油的常规饲料中添加0.02%的COS可以促进异育银鲫生长,改善肠道结构,提高鱼体非特异性免疫功能;氧化豆油会对异育鲫鱼的生长和健康造成负面影响,在该饲料中添加0.04%的COS可改善由氧化豆油引起的负面影响,使异育银鲫的健康程度达到正常水平。

In order to study the effects of chitosan oligosaccharides(COS)on growth performance,intestinal structure and non-specific immune function of crucian carp(Carassius auratus gibelio),eight experimental diets were formulated which added 0,0.02%,0.04%and 0.06%COS into basal diets containing normal soybean oil or oxidized soybean oil,respectively,and those diets were named as CG,OO,CG-200,CG-400,CG-600,OO-200,OO-400 and OO-600,respectively.The diet which did not add COS and take normal soybean oil as oil material(CG)was set as a positive control group,and the diet which did not add COS and take oxidized soybean oil as oil material(OO)was set as a negative control group.A total of 960 crucian carp with an initial body weight of(7.60±0.05)g were randomly divided into 8 groups with 3 replicates(net cages)per group and 40 fish per replicate,and cultured in a pond net cage for 72 d.The results showed that,compared with CG group,the specific growth rate(SGR)of CG-200 group was increased by 16.20%(P<0.05),but that of CG-400 and CG-600 groups had no significant change(P >0.05);the intestinal fold height and intestinal wall thickness were increased by 86.84%and 20.45%(P<0.05),the intestinal fold width was decreased by 12.18%(P >0.05),the serum superoxide dismutase(SOD)activity was increased by 6.59%(P >0.05)and the serum malondialdehyde(MDA)content was decreased by 16.94%(P >0.05)of CG-200 group;the SGR was decreased by 8.10%(P<0.05),the intestinal fold height was decreased by 17.81%,the intestinal fold width was increased by 70.30%(P<0.05),the intestinal wall thickness was decreased by 30.33%(P >0.05),the serum SOD activity was decreased 27.35%(P<0.05)and the serum MDA content was increased by 25.72%(P<0.05)of OO group.Compared with the OO group,the SGR of OO-200,OO-400 and OO-600 groups was tend to increase(P >0.05).The intestinal fold height was increased by 18.89%(P<0.05),the intestinal fold width was decreased by 42.99%(P<0.05),the intestinal wall thickness was decreased by 38.35%(P >0.05),the serum SOD activity was increased by 40.90%(P<0.05)and the serum MDA content was decreased 16.20%(P >0.05)of OO-400 group.The fish of OO-400 group achieved the similar states in SGR,intestinal structure,serum SOD activity and MDA content as those of CG group.In this experiment,the results indicate that,the growth,intestinal structure and non-specific immunity of crucian carp can be improved by adding 0.02%COS to a 4%soybean oil routine diet.Oxidized oil in the diet has negative effects on the growth and health of crucian carp.Adding 0.04%COS to a 4%oxidized soybean oil diet can improve the negative effects which caused by oxidizing oil,and can adjust the health degree of crucian carp to the normal level.