Effect Of Mannan-oligosaccharide On The Growth Performance And Non-specific Immune Responses Of Juvenile Jian Carp (Cyprinus Carpio Var.Jian)

In order to investigate the effect of Mannan- oligosaccharide on the growth performance and non-specific immune responses of Juvenile Jian Carp (Cyprinus carpio Var.Jian), Single factor design was introduced in this experiment. Diets supplemented with different levels of mannose oligosaccharides are studied for juvenile growth performance, composition, digestion and absorption functions and non-specific immune function. Select weight 23.32±0.22g (P>0.05) in juvenile health of 945, were randomly divided into 7 groups with three replicates of 45 were fed with mannan oligosaccharides for the 0,50,100,150,300,450 and 600mg/kg with half homozygous diet, conducted a 60d of the growth experiment, the MOS on growth performance of juvenile, digestion and absorption capacity and body composition, at the end of the trial, Challenge assays with Aeromonas hydrophila for 17d, investigate juvenile Jian carp MOS disease resistance and immune capability. The results showed that:Compared with the control group, adding the MOS will improve the production performance of juvenile Jian carp. Add 50～300mg/kg group increased body weight gain and SGR. And with the additive amount 300mg/kg, body weight gain and SGR significantly increased (P<0.01), feed conversion rate decreased significantly (P<0.01). with the increase of adding amount, weight gain tended to decrease but not significant, and the increase of SGR and the decrease of FCR was significant (P<0.05).Compared with the control, adding the MOS can decrease serum urea nitrogen and triglycerides, increased serum total protein. When the adding amount 100mg/kg, the blood urea nitrogen levels were significant lower (P<0.05), serum total protein concentration was significant higher(P<0.05); When adding amout was 150mg/kg, the triglyceride decreasing achieved significant level (P<0.05).Compared with control, add the MOS can significantly increase intestinal weight, intestinal length, gut length index and the post-intestinal fold height (P<0.01), significantly increased intestinal body index and foregut plica height (P<0.05), the intestinal fold height was not significant (P<0.05); intestinal lipase activity increased significantly (P<0.05), the chymotrypsin, intestinal amylase and intestinal AKP activity were significantly increased (P<0.0l), had no significant effect on trypsin (P>0.05); reduce the number of E. coli bacteria (P<0.05), while increasing the lactic acid bacteria and Bifidobacteria Microflora (P<0.05), and when the adding amout 300mg/kg significantly inhibited intestinal Escherichia coli,the proliferation of lactic acid bacteria were significantly promoted (P<0.01).Compared with the control, add the MOS can increase carcass crude protein, crude fat content and decrease moisture content, less impact on the ash. When the adding amount was higher than 100mg/kg, each body of water content on add group were significantly decreased (P<0.05); when the adding amount was 300mg/kg, it significantly increased the crude protein content (P<0.01), significantly increased lipid content (P<0.05); impact on the ash was not significant (P>0.05).Compared with the control, add the MOS can improve the animal's absolute and relative immune organ weight, blood cell counts and lysozyme activity of the body to increase non-specific immunity of animals and attack by pathogens is reflected in survival rate. Adding 300mg/kg MOS will significant improve the spleen weight in juvenile (P<0.01); the head kidney weight increased significantly (P<0.05); the renal effects was not significant (P>0.05); juvenile Jian carp spleen body index had significant effect (P<0.01), while the former, the kidney body index had no significant effect (P>0.05); red blood cells and white blood cell count were significantly increased (P<0.01); when the adding amount more than 150mg/kg the phagocytic rate reached a significant level (P<0.01), and the increases maximized when adding amount at 300mg/kg; it have significant effect on serum lysozyme activity in viable cells immune after 17d (P<0.01), significantly affect the survival rate (P<0.05).Conclusion:The appropriate amount of mannan oligosaccharides can improve the production performance of juvenile Jian carp, mainly through the promotion of intestinal growth, optimize gut microflora, improve digestive enzyme activities, thereby improving feed efficiency, promote the body nutrient deposition; and by promoting immune organs head kidney and spleen, improve the growth of non-specific immunity, and improve disease resistance in juvenile. On the condition of 37% dietary protein contented, according to indicators of growth performance and body composition, the 300mg/kg MOS level was best determined in Juvenile Jian Carp(23.32-82.92g).