Partial Replacement Of Fish Meal By Pig And Chicken Blood Protein In Diets For Hybrid Grouper (Epinephelus Fuscoguttatus ♀×E.lanceolatus ♂)

Two feeding trials were conducted to evaluate the feasibility of partial replacement of fish meal by pig blood cell meal,chicken blood cell meal or spray-dried chicken plasma used in diets for hybrid grouper(Epinephelus fuscoguttatus ♀×E.lanceolatus ♂),and compare the superiority-inferiority of two kinds of blood cell meal,respectively,based on growth performance,body composition,non-specific immunological indices and hematological parameters.The feeding trials were conducted in an indoor temperature-controlled recirculating freshwater system.The results and conclutions of this research are presented as follows: 1.Four isonitrogenous and isoenergetic diets(D1,D2,D3 and D4)were formulated to evaluate the feasibility of partial replacement of fish meal by pig blood cell meal or chicken blood cell meal,and compare the superiority-inferiority of two kinds of blood cell meal included in 48.00% and 42.36% fish meal diets for hybrid grouper,respectively.Each diet was randomly assigned to triplicate tanks of 30 fish [initial body weight(150.17 ± 0.22)g].Fish were fed to apparent satiation twice daily(08:00 and 16:00)over 56.00 days.The results showed that no significant differences in survival rate and specific growth rate were found among treatments(P>0.05).With fish fed the diets containing 42.36% fish meal,feed intake rate increased significantly(P<0.05),whereas protein efficiency rate,feed efficiency rate,protein deposition rate,lipid deposition rate,protein digestibility,total amino acid digestibility,lysine digestibility and methionine digestibility decreased significantly(P<0.05).With fish fed the diets containing 42.36% fish meal,no significant differences in crude lipid and moisture content of whole body and muscle were found among treatments(P>0.05),whereas crude protein content of whole body and muscle decreased significantly(P<0.05),but ash content of whole body and muscle increased significantly(P<0.05).With fish fed the diets containing 42.36% fish meal,serum peroxidase activity,red blood cell count and hematocrit had no significant differences(P>0.05),but serum lysozyme activity,serum protein content,hemoglobin content decreased significantly(P<0.05).In the 48.00% fish meal groups,there were no significant differences in the growth,feed utilization,body composition,non-specific immunity and hematological indices of tested fish fed pig blood cell meal or chicken blood cell meal(P>0.05).In the 42.36% fish meal groups,the tested fish fed pig blood cell meal had a significantly higher protein efficiency rate,feed efficiency rate,protein deposition rate,lipid deposition rate,protein digestibility,total amino acid digestibility,lysine digestibility,methionine digestibility,whole-body crude protein content,serum lysozyme activity,serum protein content and hemoglobin content compared to those fed chicken blood cell meal(P<0.05),while feed intake rate was significantly lower(P<0.05).In conclusion,when in the diets for hybrid grouper fish meal inclusion level is replaced from 48.00 to 42.36% by pig blood meal or chicken blood meal,growth performance of the fish shows no significant difference,but feed efficiency rate decreases significantly.The pig blood cell meal has a better substitution effect of fish meal than chicken blood cell meal used in diets for hybrid grouper.2.Five isonitrogenous and isoenergetic diets(F50P0,F45P5,F40P9,F35P14 and F30P18)were formulated to evaluate the feasibility of partial replacement of fish meal by spray-dried chicken plasma included in diets for hybrid grouper,in which the fish meal protein was replaced 0.00,10.00,20.00,30.00 and 40.00% by spray-dried chicken plasma,respectively.Each diet was randomly assigned to triplicate tanks of 30 fish [initial body weight(22.76±0.12)g].Fish were fed to apparent satiation twice daily(08:00 and 16:00)over 49.00 days.The results showed that no differences in feed intake rate,red blood cell count and hematocrit were found among treatments(P>0.05).With decreasing dietary fish meal levels from 50.00 to 40.00%,there were no significant differences in the survival rate,feed efficiency rate,specific growth rate,protein efficiency rate,lipid deposition rate,protein digestibility(P>0.05),and thereafter showed a significantly declining tendency gradually(P<0.05).The protein deposition rate,total amino acid digestibility,lysine digestibility,methionine digestibility significantly increased with decreasing dietary fish meal levels from 50.00 to 45.00%(P<0.05),and thereafter showed a significantly declining tendency(P<0.05).The crude protein,crude lipid,ash content of whole body and crude protein,crude lipid content of muscle were significantly affected by dietary fish mea levels(P<0.05),while moisture content of whole body and moisture,ash content of muscle showed no significant differences(P>0.05).The serum lysozyme activity,serum peroxidase activity significantly increased with decreasing dietary fish meal levels from 50.00 to 40.00%(P<0.05),and thereafter showed a significantly declining tendency(P<0.05).The serum protein content,hemoglobin content significantly increased with decreasing dietary fish meal levels from 50.00 to 45.00%(P<0.05),and thereafter showed a significantly declining tendency(P<0.05).In conclusion,according to the growth performance,body composition,non-specific immunological indices and hematological parameters observed in the experiments,it can be concluded that in the diet for hybrid grouper fish meal inclusion level can be replaced 10.00% by spray-dried chicken plasma.