| Purpose:This experiment was conducted to investigate the effects and mechanism of Microcapsules embedding "Essential oil+Organic acids" on production performance of Cherry Valley Duck,to explore a suitable addition amount of Microcapsules embedding "Essential oil+Organic acids" for Meat duck.This study will provide the theoretical basis for the application of Microcapsules embedding "Essential oil+Organic acids" in Cherry Valley Duck.Method:A total of 900 male one-day-old cherry valley ducks were randomly allocated to 5 groups(Control group,group Ⅰ,group Ⅱ,groupⅢ,groupⅣ)with 6 replicates per group and 30 ducks per replicate.Control group was fed the basal diet,group I were added with 400 mg/kg 10%Bacitracin zinc,The other three treatments were added with 100 mg/kg,200 mg/kg,300 mg/kg Mixed microcapsules in the basal diet(Content is shown in table 1).This experiment last for 42 days and were divided into two stages:1 to 21 days for the first phase,22 to 42 days for the second phase.Growth performance,serum biochemical indices,slaughter performan,Muscle quality,immune organ index,content of Nitrogen and Crude ash and Total phosphorus in excrement,Immunological indexes,The intestinal tissue structure and caecal Microflora in the five groups were cpmpared and analysed.Results:1 Growth performanceOn days 1 to 21,group Ⅰ,Ⅲ,Ⅳsignificantly decreased the feed/gain ratio(F/G)compared with control group(P<0.05);On days 22 to 42,group Ⅰ significantly increased the average daily gain(ADG)(P<0.05),and GroupⅢ,Ⅳvery significantly increased the ADG compared with control group(P<0.01).Group Ⅰ,Ⅲ,Ⅳvery significantly decreased the F/G compared with control group(P<0.01).On days 1 to 42,group Ⅰ,Ⅲ,Ⅳsignificantly increased the ADG(P<0.05),and very significantly decreased the F/G compared with control group(P<0.01).Group II significantly decreased the F/G compared with control group(P<0.05).2 Serum biochemical indexOn 42th day,group Ⅰ,Ⅲvery significantly increased the serum total protein(TP)compared with control group(P<0.01).Group Ⅰ,Ⅱ,Ⅲ,Ⅳvery significantly increased the albumin(ALB)compared with control group(P<0.01).Group Ⅰ,Ⅳvery significantly increased the alkaline pho sphatase(ALP)(P<0.01),and GroupⅢsignificantly increased alkaline phosphatase(ALP)(P<0.05)compared with control group.3 Slaughter performanceOn 42th day,the slaughter rate of group Ⅰ,Ⅱ,Ⅲ,Ⅳwas notable higher than control group(P<0.05);The eviscerated rate of group Ⅰ,Ⅲwas notable higher than control group(P<0.05);GroupⅢ,Ⅳsignificantly decreased the Abdominal fat rate compared with control group(P<0.05).4 Muscle qualityOn 42th day,GroupⅢ,Ⅳsignificantly decreased the chest muscle shear force compared with control group(P<0.05).GroupⅣsignificantly decreased the leg muscle shear force compared with control group(P<0.05).5 Nitrogen,crude ash,and total phosphorus content in fecesOn 21th day,the total phosphorus content of group Ⅰ,Ⅲ was notable lower than control group(P<0.05);GroupⅢ,Ⅳvery significantly decreased the crude ash compared with control group(P<0.01).On 42th day,groupⅣvery significantly decreased the nitrogen content compared with control group(P<0.01).The total phosphorus content of group Ⅰ,Ⅱ,Ⅲwas very notable lower than control group(P<0.01).6 Immunological indexesOn 42th day,the thymus index of group Ⅰ were significantly higher han control group(P<0.05),and the spleen index of group Ⅰ were very significantly higher han control group(P<0.01),the duodenal mucosa SIgA levels of group Ⅰ,Ⅲwere significantly higher han control group(P<0.05).7 The intestinal morphologyOn 21th day,comparing with control group,group Ⅰ,Ⅳcould very significantly optimize intestinal morphology by promoting the villus height of duodenum(P<0.01),groupⅢsignificantly increased the duodenum villus height compared with control group(P<0.05),group Ⅱ significantly decreased the duodenum villus height compared with control group(P<0.05),the duodenal fossae depth of groupⅢwere significantly lower than the control group(P<0.05),the V/C value of duodenum in group Ⅰ,Ⅲ,Ⅳ(P<0.05)had an obvious improvement.The jejunum villus height of group Ⅰ,Ⅲ,Ⅳwere very significantly higher han control group(P<0.01),and group II were significantly higher han control group(P<0.05);The jejunum crypt depth of group I,Ⅱ,Ⅲ,Ⅳwere significantly higher han control group(P<0.05),the V/C value of jejunum in groupⅢ,Ⅳ(P<0.05)had an obvious improvement.The V/C value of ileum in group Ⅰ(P<0.05)had an obvious improvement.On 42th day,comparing with control group,groupⅢcould significantly increased the V/C value of duodenum,group Ⅰ,Ⅲvery significantly increased the jejunum villus height compared with control group(P<0.01).Group Ⅰ(P<0.05),groupⅢ,Ⅳ(P<0.01)had obvious growth on the ileum villus height compared with control group.Group Ⅰ,Ⅲsignificantly decreased the villus crypt depth compared with control group(P<0.05),the V/C value of ileum in group Ⅰ,Ⅱ,Ⅳ(P<0.05),groupⅢ(P<0.01)had an obvious improvement.8 Blind gut floraOn 21th day,group Ⅰ significantly decreased the number of e.coli colonies compared with control group(P<0.05).On 42th day,groupⅣ significantly increased the Lactic acid bacteria colony number compared with control group(P<0.05).Conclusion:1 The Microcapsules embedding "Essential oil+Organic acids" added in Cherry Valley Ducks feed can improve the average daily gain,average weight and feed-weight ratio;It can increase Muscle tenderness and slaughter performance,to reduce total phosphorus content in feces,raise content of duodenal mucosal SIgA,improve the intestinal micro ecology environment,promote the growth of lactic acid bacteria and reproduction,improve intestinal organization form,improve the efficiency of digestion and absorption of feed.Thus,it can promote the growth and development of Cherry Valley Ducks.2 The suitable dosage of Microcapsules embedding "Essential oil+Organic acids" added to the diet of Cherry Valley Ducks feed is 200 mg/kg. |
