Effects Of Hydrolyzed Feather Meal On Growth,Meat Quality And Intestinal Health Of Yellow Catfish(Pelteobagrus Fulvidraco)

In order to explore the effects of hydrolyzed feather meal?HFM?instead of fish meal on the growth,quality and intestinal health of?Pelteobagrus fulvidraco?hydrolyzed feather meal was used to replace 0?Y₁?,2.5%?Y₂?,5.0%?Y₃?,7.5%?Y₄?and 10%?Y₅?fish meal in the basic diet?30%fish meal?.Five groups of iso-nitrogen and iso-energy diets were allocated.Three groups were set up in each group.The experiment was conducted in Chetianjiang Reservoir,Xinhua County,Loudi City,Hunan Province for 8 weeks.The experimental results are as follows:1.Effects of hydrolyzed feather powder on growth,meat quality and intestinal health of?Pelteobagrus fulvidraco?1.1.Effects of hydrolyzed feather meal instead of fish meal on growth performance,body composition and intestinal digestive enzymes of?Pelteobagrus fulvidraco?Compared with the control group,there was no significant difference in weight gain rate?WGR?,specific growth rate?SGR?and body composition among Y₂,Y₃ and Y₄ groups?P>0.05?.The liver-body ratio?HSI?and viscera-body ratio?VSI?of each experimental group increased significantly?P<0.05?,the intestinal amylase of Y₄ and Y₅ groups increased significantly?P<0.05?,and the intestinal trypsin of Y₃ and Y₄ groups increased significantly?P<0.05?.1.2.Effect of hydrolyzed feather meal instead of fish meal on serum biochemical indexes of?Pelteobagrus fulvidraco?Compared with the control group,the serum glutamic oxaloacetic transaminase?GOT?activity in Y₃ and Y₅ groups was significantly lower than that in the control group?P<0.05?,and the serum glucose?GLU?,total protein content?TP?and total antioxidant capacity?T-AOC?of?Pelteobagrus fulvidraco?in each experimental group were significantly higher?P<0.05?.The activity of serum alkaline phosphatase?AKP?and acid phosphatase?ACP?decreased,malondialdehyde?MDA?decreased and superoxide dismutase?SOD?increased in the diet substituted with hydrolyzed feather meal.The activity of ACP in Y₃,Y₅ and experimental groups was significantly lower than that in the control group?P<0.05?,and the content of serum MDA in Y₃,Y₄ and Y₅ groups decreased significantly?P<0.05?.Serum SOD levels in Y₃ and Y₄ groups increased significantly?P<0.05?.Compared with the control group,serum immunoglobulin?IGM?decreased significantly in Y₃ group?P<0.05?,and serum complement C3?C3?increased significantly in Y₅ group?P<0.05?.2.Effect of hydrolyzed feather meal replacing fish meal on quality of?Pelteobagrus fulvidraco?2.1 Effect of hydrolyzed feather meal instead of fish meal on body color of?Pelteobagrus fulvidraco?Observation of skin color of?Pelteobagrus fulvidraco?showed that H hydrolyzed feather meal had a tendency to make the back skin of?Pelteobagrus fulvidraco?black and the abdominal skin yellow lighter.Compared with the control group,the back skin of?Pelteobagrus fulvidraco?Y₃ group was significantly lighter and the abdominal skin yellow lighter.Detection of skin pigments showed that hydrolyzed feather meal could decrease the activity of tyrosinase in the back skin and the contents of lutein and carotenoid in the abdominal skin of?Pelteobagrus fulvidraco?.Compared with the control group,the activity of tyrosinase in the back skin and the contents of lutein and carotenoid in the abdominal skin of?Pelteobagrus fulvidraco?Y₃ group decreased significantly?P<0.05?.2.2.Effects of hydrolyzed feather meal instead of fish meal on physicochemical properties,texture and amino acid content of muscle of?Pelteobagrus fulvidraco?Compared with the control group,muscle elasticity of Y₂ group decreased significantly?P<0.05?,while that of Y₄ group increased significantly?P<0.05?.There was no significant difference in muscle hardness,cohesion,glue and chewiness among the experimental groups?P>0.05?.The content of MDA in muscle of?Pelteobagrus fulvidraco?increased significantly when the hydrolyzed feather meal replaced fish meal more than 5%?P<0.05?,and the content of collagen in muscle increased significantly when the hydrolyzed feather meal exceeded 7.5%?P<0.05?.The total free amino acid?TAA?content of muscle in Y₅group was significantly higher than that in control group?P<0.05?.The contents of alanine,tyrosine,tryptophan,serine and glycine in muscle were increased in Y₅ group.3.Effects of hydrolyzed feather meal instead of fish meal on intestinal health of Pelteobagrus fulvidraco3.1.Effect of hydrolyzed feather meal instead of fish meal on intestinal morphology of?Pelteobagrus fulvidraco?Observation of intestinal tissue slices of?Pelteobagrus fulvidraco?showed that with the increase of the proportion of hydrolyzed feather meal replacing fish meal,the villus of foregut became denser and its height increased significantly,and the thickness of muscle layer became thicker.hydrolyzed feather meal had little effect on the intestinal tissue of?Pelteobagrus fulvidraco?.However,with the increase of the proportion of hydrolyzed feather meal replacing fish meal,the villus height and muscle layer thickness of hind intestine of?Pelteobagrus fulvidraco?decreased significantly,and the villus density was The degree becomes sparse.The intestinal tissue measurements showed that with the increase of the substitution level of hydrolyzed feather meal,the villus height,the ratio of villus to recess and the thickness of muscle layer increased,while the recess depth decreased.The villus height,the ratio of villus to recess,the thickness of muscle layer and the depth of recess in Y₃,Y₄ and Y₅ groups increased significantly?P<0.05?and decreased significantly?P<0.05?.In each experimental group,the villus height,villus-to-concealment ratio and muscle thickness of the hindgut of?Pelteobagrus fulvidraco?showed a significant downward trend?P<0.05?,and the recess depth showed a significant upward trend?P<0.05?.3.2 Effect of hydrolyzed feather meal instead of fish meal on intestinal flora of?Pelteobagrus fulvidraco?The total OTUs of Y₁,Y₃ and Y₅ groups were 551,249 and 604 respectively.The unique OTUs of Y₁,Y₃ and Y₅ groups were 145,7 and 200 respectively.The dominant strains were Cetobacterium,with relative abundance of 91.11%,97.96%and 86.64%,respectively.Fusobacteria,Firmicutes and Proteobacteria were the dominant bacteria in the intestinal flora structure of Y₁,Y₃ and Y₅ groups of?Pelteobagrus fulvidraco?.Among them,Fusobacteria was the most abundant,Y₃ group was the highest,98.00%,Y₅ group was the lowest,86.71.Shannon index and bacterial Simpson index were highest in Y₅ group,lowest in Y₃ group,highest in bacterial ACE index in Y₁ group,followed by Y₅ group and lowest in Y₃ group.