The Effects Of Synbiotics On Growth Performance, Blood Biochemical Parameters And Intestinal Physiology Of Meat Ducks

The study was conducted to investigate effects of several synobiotics on growth performance,blood biochemical parameters and intestinal physiology of meat ducks.200 cherry valley meat ducklings of 4-day-old were randomly assigned to five dietary treatment groups:basal diet group(control),flavomycin group(basal diet added 4mg/kg flavomycin),synbioticsâ… group(basal diet added 0.28% synbioticsâ… ),synbioticsâ…¡group(basal diet added 0.39%synbioticsâ…¡) and synbioticsâ…¢group(basal diet added 0.075%market synbioticsâ…¢).Each group had four replicates.Experimental period was 42 days.The feed consumption was recorded and weight gain was measured for every week.At day 24 and 45,eight ducks per group were taken blood samples from wing vein and then killed,and collected immune organs and intestine samples for further analysis.Serum were separated and determined for biochemical parameters and endotoxin level.The small intestine(not including 45-day-old ducks) was cut into three 5cm segments at distal duodenum,mid-jejunum and mid-ileum.The left thymus,spleen and bursa of Fabricius were collected for relative weight of immune organs.Left cecal contents were collected and analyzed for pH and relative weight of cecum.Right cecal contents were sampled to test Lactobacillus and E.coli number and VFA concentration.The results were showed as follows:1) During the early growing period(4d-24d),the supplementation of synbiotics had significantly effects on growth performance of meat ducks,the supplementation of flavomycin,synbioticâ…¡and synbioticâ…¢significantly increased average daily gain by 8.05%(P<0.05),11.76%(P<0.05) and 9.74% (P<0.05) respectively,decreased feed to gain ration by 8.37%(P<0.05),10.46% (P<0.05) and 12.97%(P<0.05) respectively.2) Synbiotics diets had trend to decrease serum BUN(P>0.05) of meat ducks, and synbiotics decreased significantly serum TP and ALB of meat ducks(P<0.05).3) To a certain extent,the supplementation of synbiotics could decrease the serum endotoxin level of 24-day-old meat ducks(P>0.05),and promote the development of thymus and spleen of 24-day-old meat ducks(P>0.05).Synbioticâ…¢diet significantly increased the relative weight of spleen of 45-day-old meat ducks(P<0.05).4) The supplementation of synbiotics regulated the cecal microflora distribution during the early growing stage in meat ducks,synbiotics promoted the multiplication of Lactobacillus and inhibite the multiplication of E.coli. Synbioticâ… diet significantly decreased the is.coli numbers of cacel content in 24-day-old meat ducks by 16.37%(P<0.05).Synbioticâ…¡diet significantly increased the Lactobacillus numbers of cacel content of 45-day-old meat ducks by 13.90%(P<0.05).5) Synbiotics decreased the pH in cecal content and increased VFA concentration of cecal content(P<0.05).Feeding with synbioticâ… ,synbioticâ…¡and synbioticâ…¢significantly decreased the pH of cecal content in 45-day-old meat ducks by 4.92%(P<0.05),4.17%(P<0.05) and 6.86%(P<0.05) respectively. Synbioticâ… diet significantly increased VFA concentration of cecal content in 24-day-old meat ducks(P<0.05).Synbioticâ…¡diet significantly increased acetic acid concentration of cecal content in 24-day-old meat ducks by 54.38%(P<0.05),and increased butyric acid concentration of cecal content in 45-day-old meat ducks by 56.58%(F<0.05) respectively.Synbioticâ…¢diet significantly increased propionic acid concentration of cecal content in 24-day-old meat ducks by 7.93%(P<0.05), and increased acetic acid and propionic acid concentration of cecal content in 45-day-old meat ducks by 50.90%(P<0.05) and 49.70%(P<0.05) respectively. Synbiotic had positive effects on intestinal mucosal villous height(VH) of 24-day-old meat ducks.Synbioticâ…¡diet or synbioticâ…¢diet significantly increased duodenum mucosal VH(P<0.05),synbioticâ… diet or synbioticâ…¡diet significantly increased jejunum mucosal VH(P<0.05).In summary,synbiotics improved growth performance,the development of immue organs,intestinal internal environment,and the histological morpholohy of meat ducks.