Effects Of Fish Meal Replacement With Cottonseed Meal Protein Hydrolysate On Growth,Immune Capability And Intestine Function Of Juvenile Chinese Soft-shelled Turtle,Pelodiscus Sinensis

With the rapid development of aquaculture industry in our country,feed industry demand for fish meal is increasing day by day,but with the exhaustion of ocean resources,fish meal resource is dwindling.Therefore,looking for fish meal protein substitute is imperative.Cottonseed meal protein hydrolysate was made after cottonseed meal enzyme solution,its high content of small molecules peptides,good digestion and absorption,has been shown can be used in the feed of crucian carp and Jian carp.This study selects the reptile species-Chinese soft-shelled(Pelodiscus sinensis)as experimental animals,initial research the effects of fish meal replacement with cottonseed meal protein hydrolysate on growth,immune capability and intestine function of juvenile Chinese soft-shelled,Pelodiscus sinensis.The goal of this study was to explore the feasibility of fish meal replacement with cottonseed meal protein hydrolysate,and provide the scientific basis for development low cost,quality and efficient Chinese soft-shelled feed with new protein source.Provide guarantee for sustainable,healthy breeding of Chinese turtle.This research mainly content three parts:1 Effects of fish meal replacement with cottonseed meal protein hydrolysate on production performance,body composition,immune and antioxidant capability of juvenile Chinese soft-shelled,Pelodiscus sinensis.The study mainly evaluated the effects of fish meal replacement with cottonseed meal protein hydrolysate(CPH)on production performance,body composition,immune and antioxidant capability of juvenile Chinese soft-shelled,Pelodiscus sinensis,A total of 450 turtles,which the initial weight is 18.96 ±0.15 g,randomly assigned to the 15 cement pools(2 m × 2 m × 1.2 m,the depth of water is 0.45 m).Turtles were fed by five isonitrogenous and isoenergetic diets were formulated to replace 0(control group),5%,10%,15%fish meal protein by CPH(CPHO,CPH5,CPH10,CPH15)and CPH15L was CPH15 with micro capsule-L-lysine supplement.The feeding trial for 60 days.The results indicated that the final body weight of turtles fed with the CPH15L diet was significantly higher(P<0.05)than those fed with CPHO and CPH5 diet,while no significantly differences were observed among rest.The diets with CPH increased the weight gain(WG),specific growth rate(SGR)and feed conversion rate(FCR),but no significant differences were found among groups(P>0.05).The feed intake(FI)showed same tend and highest FI showed in turtles fed with diets CPH 15(P<0.05).Protein efficiency ratio(PER)and nitrogen retention efficiency(NRE)decreased when dietary fish meal was replaced with CPH,but no significant differences appeared among the groups(P>0.05).Energy retention efficiency(ERE)showed no significant differences appeared among all the groups(P>0.05).Whole-body crude protein,ash,crude lipid and moisture content varied slightly as dietary CPH levels increasing(P>0.05).The plasma total protein and albumin and globulin levels had no significant differences among all the groups(P>0.05).Plasma lysozyme and acid phosphatase(ACP)activities showed a little increase compared with control group,but no significant differences(P>0.05).The plasma myeloperoxidase(MPO)activities in turtle fed diets CPH5 significantly higher than control group(P<0.05),while no significant differences were found in the resting groups(P>0.05).Plasma protein carbonyl(PC)levels in CPH5 significantly lower than control and CPH 15(P<0.05).Plasma malondialdehyde(MDA)levels in turtles fed diets with CPH5,CPH 10,CPH 15 and CPH15L showed no significant differences compared with control group(P>0.05),but a decrease trend could be observed.The turtle fed CPH5 and CPH 10 diets showed higher plasma superoxide dismutase(SOD)activities of than the control(P<0.05).The results indicated that replacing up to 15%of dietary fish meal protein with CPH can improve the growth and feed intake of juvenile Chinese soft-shelled turtle and 10%fish meal protein was replacement by CPH can increased immune and antioxidant capability of turtles.2 Effects of fish meal replacement with cottonseed meal protein hydrolysate on liver function and immune gene expression of juvenile Chinese soft-shelled,Pelodiscus sinensis.This study was conducted to investigate the effects of fish meal replacement with cottonseed meal protein hydrolysate on liver function and immune gene expression of juvenile Chinese soft-shelled,Pelodiscus sinensis.The experimental design and feeding trial was the same to the first experiment.The results indicated that the activities of plasma glutamic-pyruvic transaminase(GPT)in turtle fed CPH5 diet significant lower than the resting 4 groups(P<0.05).The same tent observed in the plasma glutamic oxalacetic transaminase(GOT),but no significant differences among all the groups(P>0.05).The activities of liver GPT and GOT showed a gradual decline was observed as dietary CPH level increasing,but no significant differences among all the groups(P>0.05).Liver total antioxidant capacity(T-AOC)and the activities of catalase(CAT)in turtles fed CPH5 diet showed significant differences from those in the control group(P<0.05).The turtle fed with CPH5,CPH10,CPH15 and CPH15L diets were observed a little increased of the activities of liver SOD,nevertheless,no significant differences from the control(P>0.05).The liver malondialdehyde(MDA)content presented opposite phenomenon.The content of protein carbonyl(PC)in liver of turtles fed diets CPH5,CPH 10 and CPH15L showed significant differences from the control(P<0.05).The turtles in experimental groups appeared a significantly increased of the relative expression of IL-1?compared with control group(P<0.05),and the turtle fed diet with CPH5 showed the highest relative expression of IL-1 ?.TLR4 and TLR5 gene relative expression presented the same trend as the IL=1?,but there was no significant difference among all the groups(P>0.05).The relative expression of TLR8 in turtles fed CPH5 and CPH 10 diets showed a slightly increased than the control(P>0.05).The results indicated that replacing up to 10%of dietary fish meal protein with CPH can play a role in protecting the liver of juvenile Chinese soft-shelled turtle,which can also strengthen the liver transaminase activitities,antioxidant capacity and the immune genes expression.3 Effects of fish meal replacement with cottonseed meal protein hydrolysate on intestinal histology,digestive and absorptive enzymes activities and immune gene expression of juvenile Chinese soft-shelled,Pelodiscus sinensis.This study aimed to determine the effects of fish meal replacement with cottonseed meal protein hydrolysate on intestinal histology,digestive and absorptive enzymes activities and immune gene expression of juvenile Chinese soft-shelled,Pelodiscus sinensis.The experimental design and feeding trial was the same to the study one.The results indicated that the activity of trypsin was significantly higher than that in the CPH0 with the increasing of replacement level(P<0.05),but no significant differences were found between CPH0 and CPH15L(P>0.05).The turtles in CPH5 and CPH10 significantly enhanced the AMS activity than that in the CPH15L(P<0.05),while no significant differences were found in the resting 4 groups.Turtle fed CPH5 diet showed higher LPS activity than those fed with CPH0,CPH15 and CPH15L diets(P<0.05).The activities of Na+K+-ATPase and pepsin both showed a little enhancement as the FM replacement with CPH(P>0.05),but there is a decrease trend of both enzymes activity with the replacement level increasing.The activity of y-GT showed no significant difference among all the groups(P>0.05).The turtles in CPH5 and CH10 showed higher villus height than those in other groups(P<0.05).There were on significant differences among CPH0,CPH15 and CPH15L.The depth of crypt in turtles fed the CPH15L diet significantly higher than that in the control and CPH15(P<0.05).The length of microvilli in turtles fed diet with CPH showed a significant increase compared with control group(P<0.05),and the turtle fed diet with CPH5 showed the highest value of the length of microvilli.The turtles in experimental groups appeared a significantly increased of the relative expression of IL-1?compared with control group(P<0.05).TLR4 gene relative expression in CPH5 and CPH10 significant difference among the other groups(P<0.05),and in CPH15 and CPH15L showed a slightly higher than the control group(P>0.05).Turtles fed diet with CPH5 showed higher TLR5 gene relative expression than those in the control and CPH 15(P<0.05).The relative expression of TLR8 in CPH5 and CPH10 significant difference compared with control group(P<0.05),and in CPH 15 and CPH15L showed a slightly higher than the control group(P>0.05).The results indicated that replacing up to 10%of dietary fish meal protein with CPH can enhance the intestinal digestive and absorptive enzymes activitities,which can also promote the development of intestinal villi and immune genes expression of juvenile Chinese soft-shelled turtle.