Study Of Nutrition Regulation Effect Of Gluconic Acid On Broilers And Its Function Mechanism

540 one day old Rose 308 birds were randomly assigned into 6 groups each with 6 replications of 15 birds each.The control was provided basal diet,Treatments were basal diet added 0.08%,0.15%,0.20%,0.30%and 0.40%GA.The trail last 42 days.To study the effects of GA on performance,slaughter index,utilization rate of nutrient substance,small intestine content enzyme activity,small intestine morphology,cecal microbe and blood biochemical indicator on broilers.The purpose of this experiment was to investigate the feasibility of GA on broiler,the suitable amount in feed,and their mechanismThe main results were showed as follows:(1)GA had no significant differences in feed intake in each stage(P＞0.05);the addition of 0.15%GA significantly increased weight gain in each stage(P＜0.05);in the early(0～21d),the addition of 0.20%GA significantly decreased F/G by 2.67%(P＜0.05),in the last(22～42d),the addition of 0.15%GA significantly decreased F/G by 1.72%(P＜0.05),through the whole period,the addition of 0.15%and 0.20%GA significantly decreased F/G by 1.89%and 1.61%(P＜0.05), respectively.(2)In 21d the addition of 0.15%～0.30%GA significantly increased the apparent utilization rate of crude protein and calcium(P＜0.05),the addition of 0.15%and 0.30%GA significantly increased the apparent utilization rate of phosphor(P＜0.05),the addition of 0.20%GA significantly increased the apparent utilization rate of iron(P＜0.05), the addition of 0.20%and 0.30 GA significantly increased the apparent utilization rate of zinc(P＜0.05);in 42d the addition of 0.15%,0.20%and 0.40 GA significantly increased the apparent utilization rate of crude protein and phosphor(P＜0.05),the addition of 0.15%～0.30 GA significantly increased the apparent utilization rate of calcium(P＜0.05), the addition of 0.15%～0.40 GA significantly increased the apparent utilization rate of iron and zinc(P＜0.05),the addition of 0.20%～0.40%GA significantly increased the apparent utilization rate of copper(P＜0.05).GA had no significant differences in the utilization rate of copper in each stage(P＞0.05).(3)In 21d the addition of 0.15%GA significantly increased the slaughter ratio and the half thorax ratio(P＜0.05),the addition of 0.15%and 0.40%GA significantly increased the whole thorax ratio(P＜0.05);in 42d the addition of 0.15%and 0.20%GA significantly increased the slaughter ratio(P＜0.05),the addition of 0.15%GA significantly increased the the half thorax ratio(P＜0.05),the addition of 0.15% and 0.30%GA significantly increased the the whole thorax ratio(P＜0.05).(4)There were no significant difference between the trial group and the control group in muscle pH and the water-holding capacity of musculus(P＞0.05)(5)The diets added with GA could increased the immunity organ index.In 21d the addition of 0.15%GA significantly increased the the index of thymus(P＜0.05),the addition of 0.15%and 0.20%GA significantly increased the the index of spleen(P＜0.05),GA had the trend of increasing the index of bursa(P＞0.05),in 42d the addition of 0.15%GA significantly increased the the index of thymus(P＜0.05),the addition of 0.20%GA significantly increased the the index of spleen(P＜0.05),the addition of 0.15%,0.20%and 0.40%GA significantly increased the the index of bursa (P＜0.05).(6)In 21d,compared with the control group,the pH of duodenum content decreased 2.27%(P＜0.05),2.64%(P＜0.05),2.75%(P＜0.05),2.85%(P＜0.01),3.53% (P＜0.01),respectively,the pH of jejunum content decreased 0.41%(P＞0.05),2.35% (P＜0.05),1.54%(P＞0.05),3.17%(P＜0.05),3.39%(P＜0.01),respectively,the pH of ileum content decreased4.69%(P＜0.05),4.26%(P＜0.05),4.48%(P＜0.05),6.70%(P＜0.01),6.38% (P＜0.01),respectively,the pH of proventriculus and gizzard decreased 3.08% (P＞0.05),5.07%(P＞0.05),5.95%(P＜0.05),3.85%(P＞0.05),8.43%(P＜0.01),respectively;in 42d,compared with the control group,the pH of duodenum content decreased 2.38% (P＞0.05),2.27%(P＞0.05),1.75%(P＞0.05),3.58%(P＞0.05),5.14%(P＜0.05), respectively,the pH of jejunum content decreased 1.94%(P＞0.05),4.34%(P＞0.05),1.42% (P＞0.05),3.80%(P＞0.05),4.97%(P＜0.05),respectively,the pH of ileum content decreased 2.78%(P＞0.05),4.27%(P＞0.05),2.30%(P＞0.05),3.35%(P＞0.05),4.65%(P＜0.05), respectively,the pH of proventriculus and gizzard content decreased 11.72%(P＞0.05),8.95 %(P＞0.05),14.69%(P＜0.05),15.28%(P＜0.05),17.25%(P＜0.05),respectively.(7)The diets added with GA could increased the digestive enzyme activity.In 21d,the addition of 0.15%GA significantly increased the activity of arnylase,lipase(P＜0.05)and trypsin(P＜0.01),the addition of 0.20%GA significantly increased the activity of trypsin(P＜0.05);in 42d the addition of 0.15%GA significantly increased the activity of amylase(P＜0.05),the addition of 0.20%GA significantly increased the activity of lipase and trypsin(P＜0.05).(8)In 21d,the addition of 0.15%～0.40%GA significantly increased the villus height of duodenum and jejunum(P＜0.05);in 42d,the addition of 0.20%GA significantly increased the villus height of duodenum(P＜0.05),the addition of 0.15%GA significantly increased the villus height of jejunum(P＜0.05);GA had no significant differences in crypt depth and small intestine wall thickness of duodenum and jejunum(P＞0.05).(9)Compared with the control group 42-d-old broiler,the number of bifidobacteria increased 5.09%(P＜0.05),7.50%(P＜0.01),7.11%(P＜0.01),7.94% (P＜0.01),8.14%(P＜0.01),respectively;the number of lactobacilli increased 1.34% (P＞0.05),2.34%(P＞0.05),4.37%(P＜0.05),4.84%(P＜0.05),4.90%(P＜0.05),respectively; the number of Escherichia coli decreased 4.85%(P＞0.05),7.84%(P＜0.05),7.61% (P＜0.05),7.26%(P＜0.05)和7.51%(P＜0.05),respectively.(10)In 42-d-broiler,the addition of 0.15%and 0.20%GA significantly increased the serum TP and GLOB(P＜0.05);there were no significant effect on serum ALB(P＞0.05);the addition of 0.15%GA significantly decreased the serum BUN(P＜0.05);the addition of 0.15%～0.40%GA significantly increased the activity of SOD(P＜0.05);the addition of 0.15%～0.40%GA significantly decreased the MDA;the addition of 0.15%～0.30%GA significantly increased the concentration of serum IgG(P＜0.05);the addition of 0.15%,0.20%and 0.40%GA significantly decreased the serum TC and increased H/L(P＜0.05);the addition of 0.15% GA significantly decreased the serum TG(P＜0.05);the addition of 0.15%and 0.40%GA significantly increased the serum HDL;birds fed GA had the trend of decreasing the serum LDL(P＞0.05).