Effects Of Hermetia Illucens Larvae Powder Replacing Fish Meal On Growth,Muscle Quality And Immunity Of GIFT Oreochromis Niloticus

In order to develop new protein resources,this paper studied the growth performance and feed utilization,body composition,muscle quality,antioxidant,alkaline phosphatase,serum biochemical indicators,intestinal morphology and the expression of immune factors of Hermetia illucens larvae powder instead of fish meal for Genetic Improvement of Farmed Tilapia(GIFT Oreochromis niloticus).The experiment selected the initial weight of 9.22±0.01 g of 600 tilapia with good health and uniform specifications,and randomly divided into 5 groups D0(fish meal control group),S1(replaces 25% fish meal),S2(replacs 50% fish meal),S3(replaces 75% fish meal),S4(replaces 100% fish meal),4parallel in each group,30 fish in parallel.Breeding test in indoor circulating aquaculture system(A culture barrel has a volume of 350 L)for 8 weeks.The main findings are as follows:1.Effects of Hermetia illucens larvae powder replacing fish meal on growth performance and feed utilization of GIFT Oreochromis niloticusCompared with the control group,25% and 100% of the fish meal in the substitute feed of the Hermetia illucens larvae powder significantly increased the weight gain rate,specific growth rate and protein efficiency of the GIFT Oreochromis niloticus(P<0.05),and the processing group works best that were replaced 100%.Substituting 75% and 100% fish meal in feed significantly increased the feeding rate and the ratio of the visceral to the GIFT Oreochromis niloticus(P<0.05).2.Effects of Hermetia illucens larvae powder replacing fish meal on whole fish,muscle composition and muscle quality of GIFT Oreochromis niloticusCompared with the control group,the replacement of 50% and 100% fish meal byHermetia illucens larvae powder in the feed significantly reduced the crude protein of GIFT Oreochromis niloticus whole fish(P<0.05),replacing 100% of the fish meal significantly increased the crude fat content of GIFT Oreochromis niloticus whole fish(P<0.05),and the replacement of 25%-100% fish meal can significantly reduce the crude ash content of GIFT Oreochromis niloticus whole fish(P<0.05).Compared with the control group,replacing50% and 75% of the fish meal significantly reduced the crude protein of GIFT Oreochromis niloticus muscle(P<0.05);and replacing 25%-100% of fish meal significantly increased the crude fat content of GIFT Oreochromis niloticus muscle(P<0.05).Compared with the control group,the replacement of 75% of the fish meal by the Hermetia illucens larvae powder in the feed can significantly increase the hardness,brittleness,elasticity,viscosity,chewiness,adhesion,cohesiveness and recovery of GIFT Oreochromis niloticus muscles(P<0.05),while the Hermetia illucens larvae powder replaceing 100% fish meal treatment group significantly reduced the hardness,brittleness,chewiness and recovery of GIFT Oreochromis niloticus muscle(P<0.05).Hermetia illucens larvae powder replacement of fish meal treatment group,the muscle viscosity and shear strength of GIFT Oreochromis niloticus were significantly increased(P<0.05).Replacing75% and 100% of the fish meal in the feed significantly reduced the water holding capacity of GIFT Oreochromis niloticus(P<0.05),but the treatment group replacing 100% fish meal increased the muscle p H and cooked meat of GIFT Oreochromis niloticus that the rate is the best.Compared with the control group,Hermetia illucens larvae powder replacement25%,50% and 75% of the fish meal in the substitute feed did not have a negative effect on the amino acid content of the muscle of the GIFT Oreochromis niloticus(P>0.05).3.Effects of Hermetia illucens larvae powder replacing fish meal on serum biochemical and immunological indexes of GIFT Oreochromis niloticusCompared with the control group(D0),the Hermetia illucens larvae powder in the feed replacing different proportions(25%-100%)of fish meal against GIFT Oreochromis niloticus serum superoxide dismutase(SOD),malondialdehyde(MDA)and catalase(CAT)activity had no significant effect(P>0.05);while replacing 50%(S2)and 75%(S3)fish meal in feed significantly increased the total antioxidant capacity of GIFT Oreochromis niloticus serum(P<0.05).compared with the control group(D0),the substitution of differentproportions of Hermetia illucens larvae powder in the feed had no significant effect on the AKP activity of GIFT Oreochromis niloticus serum(P >0.05).Compared with the control group(D0),the Hermetia illucens larvae powder in the feed replaced different proportions of fish meal to the total cholesterol(TC),total protein(TP)and blood urea nitrogen(BUN)of the GIFT Oreochromis niloticus had no significant effect(P>0.05);the replacement of 100%(S4)fish meal by Hermetia illucens larvae powder in feed significantly reduced the content of GIFT Oreochromis niloticus serum Albumin(ALB)(P<0.05);The replacement of 25%(S1)fish meal by the Hermetia illucens larvae powder significantly increased the serum triglyceride(TG)content of GIFT Oreochromis niloticus(P<0.05).4.Effect of Hermetia illucens larvae powder replacing fish meal on intestinal morphological structure of GIFT Oreochromis niloticusCompared with the control group,Hermetia illucens larvae powder replacing 25%,50%,75% and 100% of the fish meal in the feed significantly increased the thickness of the midgut muscle layer of the GIFT Oreochromis niloticus(P<0.05),and the Hermetia illucens larvae powder replacing 100% fish meal had the best effect.Compared with the control group,the treatment group of the Hermetia illucens larvae powder in the feed instead of the fish meal did not have a negative impact on the GIFT Oreochromis niloticus intestinal tract.5.Effect of Hermetia illucens larvae powder replacing fish meal on the expression of immune factors in GIFT Oreochromis niloticusCompared with the control group,The expression level of il-1 gene in the Hermetia illucens larvae powder replaced the fish meal fed with the fish meal of the GIFT Oreochromis niloticus liver(50%(S2)group)and the spleen(50%(S2),75%(S3)and100%(S4)group)was significantly up-regulated(P<0.05),and the expression level was the highest in the treatment group replacing 50%(S2)fish meal.Compared with the control group,The expression levels of il-2 gene in the Hermetia illucens larvae powder replaceing the fish meal fed with the fish meal of the GIFT Oreochromis niloticus liver(25%(S1),75%(S3)and 100%(S4))and the spleen(50%(S2)and 100%(S4)groups were significantly up-regulated(P<0.05),and the expression level of the treated group replacing100%(S4)Hermetia illucens larvae powder was the highest.Compared with the control group,The expression levels of il-10 gene in the Hermetia illucens larvae powder replaceing the fish meal fed with the fish meal of the GIFT Oreochromis niloticus liver(25%(S1),50%(S2)and 100%(S4))and the spleen(50%(S2)and 100%(S4))groups were significantly up-regulated(P<0.05),and the expression level of the fish meal treatment group with 50%(S2)replaced by Hermetia illucens larvae powder was the highest.Compared with the control group,the expression of cyp1 a gene in the liver of the GIFT Oreochromis niloticus(25%(S1),and spleen 100%(S4))fed by the Hermetia illucens larvae powder instead of the feed was significantly upregulated(P<0.05).Compared with the control group,The expression levels of tlr2 gene in the Hermetia illucens larvae powder replaces the liver of the GIFT Oreochromis niloticus fed by the fish meal(25%(S1),50%(S2),75%(S3)and 100%(S4))and the spleen(50%(S2),75%(S3)and 100%(S4)groups)were significantly up-regulated(P<0.05),what were replaced by50%(S2),75%(S3)and the 100%(S4)group of Hermetia illucens larvae powder treatment group had the highest expression level.In summary,the addition of Hermetia illucens larvae powder to the feed can promote the growth,improve muscle quality,improve immunity and antioxidant capacity,and enhance the digestion and absorption of of GIFT Oreochromis niloticus.Hermetia illucens larvae powder can be used as a protein feed for GIFT Oreochromis niloticus feed instead of fish meal.The proportion of Hermetia illucens larvae powder to replace fish meal should not exceed 75%,otherwise it will harm the health of GIFT Oreochromis niloticus juveniles and reduce the muscle quality of fish.In the case of adding 12% fishmeal to GIFT Oreochromis niloticus feed,it is recommended to black.The proportion of Hermetia illucens larvae powder replacing fish meal in GIFT Oreochromis niloticus juvenile compound feed is50-75%.