Effects Of Compound Acidifier On Production Performance, Digestive Enzyme Activities Of Chyme And Intestinal Microbiota In Broiler

The present experiment was conducted to study the effects of dietary compound acidifier on growth performance, nutrient metabolism, digestive tract pH, digestive enzyme activity and intestinal microbiota and intestinal histology in broiler. 420 1-day-old healthy Arbor Acre broilers were selected and randomly allotted into four treatments, each treatment consisted of three replicates with thirty five broilers in each replicate. Compound acidifier were added to the basal diet of the four treatments with the dosge of 0, 1000, 2000 and 3000 mg per kilogram diet, respectively. The feeding trial lasted 42 days, and experimental diets and water were available ad libitum during the entire experimental period. In addition, six broilers (three replicates, two broilers per replicate) of each treatment were used to assay the crude protein and energy availability the 7d, 14d, 21d and 35d of the experiment.Results were showed as follows:Experiment 1: Effects of different acidifiers supplement level on growth performance and carcass traits of broilersThe compound acidifier supplement increased the average daily gain( 0 to 42 days) and body weight and feed intake(21 to 42days), and reduced the feed conversion ratio on 0～21 days (P<0.05). There were not significant difference in the feed conversion ratio on 21～42days and 0～42 days (P>0.05). Especially, the dose of 2000 mg/Kg had the best effect.There were not significant difference in the slaughter rate, half net carcass rate, whole net carcass rate, breast meat ratio and leg meat ratio (P>0.05). The 0.2% and 0.3% treatment increased the abdominal fat ratio (P<0.05).Experiment 2: Effects of different acidifiers supplement level on the apparent metabolic rate of crude protein and energy in ration The acidifier treatment(1000, 2000 and 3000 mg/Kg, respectively) increased the crude protein and energy availability in ration on 7d, 14d, 21d and 35d (P<0.05).Experiment 3: Effects of different acidifiers supplement level on pH, pepsin, amylase and lipidase activity of broilersThe acidifier reduced the pH of craw, proventriculus, gizzard and duodenum contents on 21d (P<0.05); There were not significant difference in the pH of jejunum, ileum and cecum contents on 21d (P>0.05); There were not significant difference in the pH of craw, proventriculus, gizzard, duodenum, jejunum, ileum and cecum contents on 42d (P>0.05); The 0.3% treatment reduced the pH of jejunum contents on 42d (P<0.05).There were not significant difference in the pepsin activity in proventriculus and gizzard (P>0.05); The acidifier increased the pepsin activity and amylase activity in duodenum contents on 21d and 42d of boilers (P<0.05). There were not significant difference in the pepsin activity and amylase activity in jejunum contents (P>0.05). There were not significant difference in the lipidase activity in duodenum and jejunum contents on 21d and 42d of boilers (P>0.05)Experiment 4: Effects of different acidifiers supplement level on microflora and intestines morphology of broilersThe acidifier reduced the population of E.coli in ileum and cecum on 21d and 42d of the experiment (P<0.05) and increased the population of bifidobacterium in cecum on 21d (P<0.05) not significant difference. The Population of lactobacillus (P>0.05).The acidifier increased the villous length in duodenum and jejunum (P<0.05), but not significant difference the villous length in ileum (P>0.05). There were not significant difference in the villous width in every bowels segmental on 21d and 42d (P>0.05). The acidifier reduced the depth of intestine gland in duodenum on 21d (P<0.05). There were not significant difference in the depth of intestine gland in jejunum and ileum on 21d and 42d (P>0.05).