Effects Of Dietary Chitosan Oligosaccharides On Production Performance And Immune Function Of Juvenile Jian Carp(Cyprinus Carpio Var.Jian)

This experiment was conducted to investigate effects of dietary chitosan oligosaccharides to production performance, lipid metabolism, immune function and intestinal flora of juvenile Jian carp. A total of 225 fish of being average weight of (8.78±0.38 g) were randomly divided into 5 groups, and then 0,0.3%,0.6%,0.9% and 1.5% level of chitosan oligosaccharides were added in these diets each group, respectively. After the feeding trial (80 d),. index tes and challenge trial were conducted.Results the experiment shows ut infra:(1) WGR, SGR and lift hepatopancreas index of contral group were improved while employ dietary Chitosan oligosaccharides. It uncovers the significant abilities to, intestine index, fold heights of intestinal, fold density of intestinal and intestinal wall thickness(P<0.05). Here is being significant positive correlation between WGR and fold heights of the intestinal (r1=+0.834, P<0.05; r2=+0.973,P<0.01; r3=+0.868, P<0.05), which show WGR is perhaps got to changing for intestinal development has been grown by chitosan oligosaccharide in diet. Control group of Crude fat and rate of water loss was lowered more significantly ((P<0.01), that proves chitosan oligosaccharide is able to play a role to optimize meat quality of juvenile Jian carp.(2) levels of Chitosan oligosaccharide significant reduced TG and TCH in plasma(P<0.05), and significant improved HDL-C in plasma(P<0.05). Another Correlation between crude fat and HDL-C in plasma, MDA in muscle(r1=-0.928, P<0.05; r2=+0.979,P<0.01).It shows that chitosan oligosaccharide promote fat metabolism may be related with the content of HDL-C in plasma and MDA in muscle.(3) Head kidney index, phagocytic percentages, phagocytic index of leukocyte and erythrocytes, T-AOC in plasma and hepatopancreas, great significant reduced MDA in plasma and hepatopancreas were dramatically improved while Chitosan oligosaccharide added (P<0.01). There is a correlation within phagocytic index of leukocyte with T-AOC in hepatopancreas, T-AOC, MDA in plasma(r1=+0.825, P<0.05; r2=+0.722, P<0.05; r3=-0.968, P<0.01). It is no difficulty to find out the appearance to fish non-specific immune ability is embellished on account of antioxidant capacity has been increased with dietary chitosan oligosaccharide.(4) Control group of the amount of Bifidobacterium and Lactobacillus were significantly or great significant improved(P<0.05 or P<0.01), The amount of Escherichia coli in each treatment group were great significant reduced(P<0.01). Correlation existed between Bifidobacterium and Lactobacillus, Escherichia coli in intestinal(r1=-0.958, P<0.01; r2=+0.948, P<0.05; r3=-0.917, P<0.05; r4=+0.950, P<0.01; r5=-0.942, P<0.05; r6=+0.935, P<0.05). It shows that chitosan oligosaccharide inhibition of harmful bacteria growth may be associated with the beneficial bacteria proliferation.(5) Chitosan oligosaccharide can improve the survival rate, reduced the morbidity after the poison attack trial, and Have some relief for head kidney manifested as the kidney interstitial hyperemia, interstitial cell hyperplasia, renal tubular capillary congestion and expansion; spleen red and white pith were destroyed, spleen congestion, the number of lymphocytes decreased; intestinal lesions showed intestinal epithelial shedding, goblet cell was damaged, Intestinal fold adhesion; and so on. Meanwhile, chitosan oligosaccharide can significantly reduce the amount of Aeromonas hydrophila in each treatment group(P<0.05). Correlation exists between survival rate and head kidney index, phagocytic index of leukocyte, amount of Escherichia coli, Bifidobacterium, Lactobacillus, Aeromonas hydrophila(r1=+0.925, P<0.05; r2=+0.869, P<0.05; r3=+0.887, P<0.05; r4=-0.889, P<0.05; r5=+0.987, P<0.01; r6=+0.883, P<0.05; r7=-0.971, P<0.01). It shows that chitosan oligosaccharide enhance disease resistance was correlated with non-specific immunity function and intestinal immune function.To sum up, chitosan oligosaccharide can improve the production performance of juvenile Jian carp, enhance the non-specific immune ability. In addition, be able to affect some of fat metabolism. Meanwhile, chitosan oligosaccharides can improve the structure of intestinal microflora and increase capacity to anti-disease of being Aeromonas hydrophila. Regression analysis showed(YWGR=-20.865x2+40.899x+l 02.31, R2=0.926, P>0.05, XWGR=0.9801), the dietary chitosan oligosaccharide optimum of juvenile Jian carp based on WGR was 0.9801%.