Black Soldier Fly Larvae Oil And Defatted Black Soldier Fly Larvae Meal As The Feed Lipid And Protein Sources,Respectively,in Jian Carp,cyprinus Carpio Var.Jian

With intensifying shortage of fish meal and fish oil,therefore it is important to explore potential new and less expensive protein and lipid sources for successful and sustainable development of aquaculture.Insects grow in a wide range of decaying organic matter,reproduce easily,have high feed conversion efficiency and contain a high level of crude protein and fat.Black soldier fly(Hermetia illucens)is a common and widespread fly of the family stratiomyidae whose larvae can be processed into meal that contain high level of protein(42-44%)and fat(31-35%)used in animal diets.Here,we investigated the use of black soldier fly larvae as an alternate animal protein and fat source for rearing Jian carp,Cyprinus carpio var.Jian.1.Influence of black soldier fly larvae oil on growth performance,body composition,tissue fatty acid composition and lipid deposition in juvenile Jian carpBlack soldier fly larva oil(BSO)is a potential lipid source in aquafeeds,which is higher in lauric acid(21.4%-49.3%).To research the effect of dietary BSO on growth performance,fatty acids composition and lipid deposition of juvenile Jian carp,five experimental diets were formulated by replacement of 0,25%,50%,75% and 100% soybean oil(SO)with BSO.Total 300 Jian carp(10.67 ± 0.80 g)were divided randomly into five groups(triplicate per group)and fed with the diet above respectively.After 59 days feeding,growth,fatty acids composition and lipid deposition was determined.The results showed that growth,nutritional utilization and serum biochemical parameters of fish in five groups were not different(p>0.05).Fatty acids composition in the intraperitoneal fat tissue,muscle and hepatopancreas was closely relevant with diets.However,the 22:6n-3 content of treated groups was higher than that of the control group(p<0.05)in the muscle.Intraperitoneal fat index and the adipocyte size of intraperitoneal fat decreased in higher BSO intake compared with SO group(p<0.05).Relative gene expression of PPARα mRNA increased(p<0.05),while PPARγ and FAS were not affected by dietary BSO level(p>0.05).The Bcl-2/Bax ratio was not different among five groups(p>0.05).2.Effects of fish meal replacement by defatted black soldier fly larvae meal on growth,antioxidant enzyme activity,digestive enzyme activities,and intestinal morphology of Jian carpA 59 days feeding trial was carried out in Jian carp juveniles(initial mean body weight,34.78 g)to estimate the effects of fish meal replacement by defatted black soldier fly larvae meal(DBSFLM)on growth performance,oxidation resistance,digestive enzyme activities,and intestinal morphology.Five isolipidic(5.3%)and isoprotein(40.7%)diets were formulated by replacing 0%,25%,50%,75%,100% fish meal(FM)protein with graded DBSFLM levels of 0%,2.6%,5.3%,7.9% and 10.6%.Each diet was randomly assigned to triplicate groups of 20 fish per aquarium.Fish were fed three times daily to apparent satiation.The results showed that the growth performance and nutritive utilization of fish in five groups were not different(p>0.05).The content of lipid and serum cholesterol of treated groups was significantly lower than that of the control group(p<0.05).With increasing dietary DBSFLM level,the activity of the CAT increased(p<0.05).No differences in the activity of intestinal protease,lipase and diastase were observed among dietary treatments(p>0.05).The histological examination of intestine showed that when 75% or more FM protein was replaced,apparent pathological changes for example tissue disruption were observed,and relative gene expression of HSP70 in heapatopancreas increased(p<0.05).The histological examination of hepatopancreas sections showed less vacuolated with lipid deposits in treatment groups compared with control group.In conclusion,the results showed that it is possible to add 25 g kg-1diet or more black soldier fly larvae oil in Jian carp diets without compromising growth performance and nutritive utilization and improved DHA content of muscle,while it decreased lipid deposition in the intraperitoneal fat tissue by higher gene expression of PPARα.Futhermore,at least50% of FM protein(inclusion level is 5.3%)could be replaced with DBSFLM without any adverse effects on growth performance,carcass composition and digestive enzyme activities of juvenile Jian carp.While oxidation resistance weakened and severe histopathological damage was observed in intestine of juvenile Jian carp when the replacement level exceeded75%(inclusion level is 7.9%).