Evaluation Of Optimum Dietary Protein/energy Ratio Of Chinese Perch And Mud Carp,and The FCR Of Mud Carp Diet Indirect Feeding To Chinese Perch

Sinipercinae are freshwater fish species,native to East Asia,widely distributed in China,Japan,Northern Vietnam,the Korean Peninsula and the Amur River along the Russian borderlands.It comprises of two genera,eight species of Siniperca and four species of Coreoperca,in China ten species are present,among ten Siniperca chuatsi,Siniperca kneri and Siniperca scherzeri are farms widely,however,the Siniperca chuatsi farming is famous and immense.Traditionally,they are famous from ancient China due to,its good taste,fabulous nutritional value,with less intermuscular bones.Naturally,this fish is carnivorous and feed on other small fish from the beginning of life.The farming of this fish is largely based on live fish feeding,that greatly affects its culturing environment,and also cause high market price.However,after successful weaning on artificial diet,now it has a great research importance to optimize its artificial diet to improve Chinese perch farming and cost-effective culture environment to produce healthy fish and increase aquaculture production.This study reports the effect of dietary protein/energy ratio(directly,(artificial diet)and indirectly via bait fish)on Chinese perch growth performance,feed intake,feed utilization,body composition,nitrogen metabolism enzymes,genes expression and relative AMPK-m TOR signaling pathways interaction.Additionally,the effect of dietary protein/energy ratio on bait fish was also quantified.Furthermore,the role of probiotics in Chinese perch pond culture improvements were also evaluated.1.Dietary nutrients effect on novel farms species has always driven a wide research and economic interest.Chinese perch a carnivorous fish,accept artificial diet after taming,makes it essential to optimize and evaluate its nutritional and metabolic demands.However,only few studies were conducted on Chinese perch artificial diets effect on growth and metabolism.Therefore,the present study was conducted to evaluate the Chinese perch(Siniperca chuatsi)growth and metabolic response to experimental diets with different dietary protein/energy ratio.Five iso-energetic diets(18 k J/g)with graded levels of P/E ratios(30.58,33.22,35.90,38.60,and 41.35 mg/k J)named as A,B,C,D,and E were formulated.A total of 225 Chinese perch(64.89±0.28 g)were distributed into 15(350L)fiberglass tanks(15 fish per tank)assigned to five groups in triplicates and fed twice a day at 4%fish wet body weight with respective P/E ratio diets for 10weeks.The results showed that P/E ratio significantly affected Chinese perch growth performance and metabolism.Chinese perch in Group C showed significantly improved growth performance,weight gain,specific growth rate,Viscerosomatic index,Hepatosomatic index,Intraperitoneal fat,(WG,SGR,VSI,HSI,IPF)feed utilization,feed intake,feed conversion ratio,protein efficiency ratio,protein retention efficiency,energy retention efficiency,feed efficiency(FI,FCR,PER,PRE,ERE,FE)and whole body,muscle,and liver composition(moisture,protein,lipids,ash)as compared to other groups.Whereas,fish in Group A showed lowest growth performance,feed utilization and body composition as compared to other groups.The nitrogen metabolism-related enzyme activities,alanine aminotransferase(ALT),aspartate aminotransferase(AST)glutamate dehydrogenase and adenosine 5?-monophosphate deaminase(AMPD),as well as GDH and AMPD genes expression of fish in Group A were significantly lower than other groups.Similarly,among the appetite regulation genes(NPY,Ag RP,POMC and CART),gene expression of NPY and Ag Rp were significantly higher in Group C as compared to other groups.However,genes expression of CART and POMC were not affected by dietary P/E ratios.Correspondingly,the m TOR-AMPK pathway genes expression of m TOR,S6K and 4EBP1 were significantly lower and AMPK,LKB1 and e EF2 genes expression were significantly higher in Group A as compared to other groups.Furthermore,the blood biochemicals ALT,AST,total protein(TP),alkaline phosphatase(ALP),glucose(GLU),blood urea nitrogen(BUN),and triglyceride(TG)levels were also affected by the dietary P/E ratio.The present results showed that dietary P/E ratio of artificial diets,significantly affected Chinese perch growth and metabolism.Also,based on the second-order polynomial regression analysis,dietary P/E ratio of37.98 is best for the optimal growth response of Chinese perch.2.Cirrhinus mrigala is an important freshwater fish with high aquaculture potential and strong consumer preferences.Cirrhinus mrigala plays an important role in the Chinese perch farming as a live feed,that has led a great research interest to optimize its dietary requirement and culture environment for Chinese perch farming.Therefore,the present study was conducted to encompass the effect of dietary protein to energy ratios on growth performance,feed utilization,body composition,and nitrogen metabolism enzymes of C.mrigala.Five Iso-energetic diets(16 k J/g)with graded levels of P/E ratios(17.84,19.79,22.19,24.46,and 26.50 mg/k J)named as A,B,C,D,and E were formulated.A total of 300 C.mrigala fingerlings(initial weight 17.80±0.12 g)were equally distributed into five groups(in triplicate).Each group was fed twice a day at 4%wet body weight with respective P/E ratio diets for 8 weeks.Highest weight gain,specific growth rate,protein efficiency ratio,and protein retention efficiency were observed in group C with lower feed conversion ratio,Hepatosomatic index and Viscerosomatic index compared to other groups.The whole body and muscle composition were significantly influenced by the dietary P/E ratio of the diets.Among all groups,group C was significantly higher in crude protein,and ash contents,with lowest lipids level and moisture contents compared to other groups.The activities of nitrogen metabolism enzymes,Aspartate amino transferase,Alkaline amino transaminase,Glutamate dehydrogenase and Adenosine 5?-monophosphate deaminase(AST,ALT,GDH,and AMPD)were increased with increasing dietary P/E ratios.The second-order polynomial regression analysis of FCR showed that the optimal dietary P/E ratio of C.mrigala(fingerlings)was 22.61 mg/k J.3.Chinese perch,(Siniperca chuatsi)or mandarin fish,is a demersal piscivore freshwater fish.Chinese perch,special live feeding behavior makes aquaculture practice and consumer price high,that‘s droved strong research interest for live feed optimization.Therefore,the present study was conducted to investigate the indirect effect of dietary protein to energy ratio of bait fish(mrigal)(fed various dietary P/E ratio diets)on Chinese perch.Three(selected best performed diets of mrigal from second experiment)Iso-energetic diets(16 k J/g)with graded levels of P/E ratios(19.79,22.19 and 24.46 mg protein/k J),each with protein level(28.18,31.36,and 33.91%),were named as A,B,and C.A total of 90 kg live bait fish C.mrigala were distributed in nine(1000 L tanks)fed with respective P/E ratio diets(feed experimental diets for two week before feeding to Chinese perch).In another nine(1000 L tanks)Chinese perch(30 fish/tank)were distributed and fed at 4%live bait fish,twice a day for 8 weeks.The results showed that P/E ratio diets significantly affected both fish performance.Bait fish in group A showed significantly lower weight gain(WG),specific growth rate(SGR),and higher Viscerosomatic index(VSI)and Hepatosomatic index(HSI)compared to other groups.Similarly,in Chinese perch,group A,showed significantly lower WG,SGR,protein efficiency ratio(PER)and higher feed intake(FI),feed conversion ratio(FCR),VSI,HSI,and Intraperitoneal fat(IPF),compare to other groups.Bait fish in group A showed significantly lower whole-body crude protein and higher lipid contents compared to other groups.Similarly,Chinese perch of group A showed significantly lower whole body and muscle crude protein,and higher lipid contents than other groups.The nitrogen metabolism enzyme activities(ALT,AST,GDH,AMPD)and gene expression of GDH and AMPD in Chinese perch group A,was significantly lower.The AMPK and m TOR pathway gene expression showed a low energy status and protein catabolism in group A of Chinese perch.Our result shows that the dietary P/E ratio of the bait fish diet significantly affects bait fish and Chinese perch nutrition and metabolism.Probiotic application is a well-known method in aquaculture,are using to improve ponds water quality and surrounding environments.The importance of probiotic increase more when a carnivorous fish like Chinese perch is amid to culture,and to maintain healthy water quality and ponds environments.Therefore,the present study was aimed to investigate the effect of microbial probiotics on culture pool environment,Nitrobacteria and Photosynthetic bacteria(PSB)were applied(10 plants per square meter)into Chinese perch culture pool with a volume of 15m²×35m²×2.5m(length×width×height).The experimental ponds were divided into two groups with one control group.During 15 days culture period,water quality parameters(p H,Nitrite,Ammonium nitrogen(NH₄⁺-N),Total phosphorus(TP),Total nitrogen(TN),Sediments Organic Matters(SOM),Sediment Total Nitrogen(STN),Sediment Total Phosphorus(STP)and Algae populations(Chlorophyta,Bacillariophyta,and Cyanophyta)were analyzed at different interval days.The result showed that the p H in Nitrobacteria and PSB applied group were lower than the control group,Nitrite,(NH₄⁺-N),TP,and TN were also significantly lower in both experimental group than the control group.The SOM was higher in both experimental groups than the control groups,and the STP and STN were higher in both experimental groups than the control groups.The phytoplankton‘s,Chlorophyta,and Bacillariophyta were significantly lower in control group as compared to experimental group.However,the Cyanophyta ratio was significantly higher in control group compared with both experimental groups.Our result suggests that both probiotics PSB and Nitrobacteria balance ratios addition can promote healthy water quality,sediments nutrients and good environments in Chinese perch pond culture.