Effects Of Insoluble Fiber On Growth Performance,Intestinal Health And Liver Lipid Metabolism Of Broilers

This paper studied the effects of insoluble fiber on growth performance,intestinal health and nutrient metabolic rate of broilers,and investigated the effects of insoluble fiber on intestinal microecology and m RNA expression of liver lipid metabolization-related genes in broilers,so as to explore the mechanism of the mechanism of insoluble fiber on the production performance and slaughter performance of broilers.So as to provide theoretical support for the application of insoluble fiber in broiler breeding.Part 1: Effects of insoluble fiber on growth performance,slaughter performance and nutrient metabolism efficiency of broilers360 one-day-old AA broilers were randomly divided into three treatments,with 6repetition groups in each treatment and 20 broilers in each repetition group: the control group was fed with basic diet,the trial group I was added with 8 kg/t insoluble fiber,and the nutritional concentration of the diet in the trial group I was consistent with the basic diet through appropriate adjustment of the diet formula,and the trial group II was added with 8 kg/t insoluble fiber on the basic diet.The test period was42 days.The effects of insoluble fiber on growth performance and slaughter performance of broilers were studied,and the apparent metabolizable energy(ME)and nutrient metabolic utilization of diets were determined by total fecal collection method.The experimental results showed as follows: 1)Compared with the control group,the average daily gain and final weight of broilers in each trial group decreased significantly from 1 to 14 days of age(P<0.05).From 14 to 42 days of age,the average daily gain and final weight of broilers in trial group I increased significantly(P<0.05).From 1 to 42 days of age,the performance of broilers in trial group I was significantly higher than that in trial group II(P<0.05),but there was no significant difference with the control group.2)Compared with the control group,at 14 days of age,the slaughter percentage,eviscerated percentage and leg muscle percentage of each trial group were significantly increased(P<0.05),and the abdominal fat percentage was significantly reduced(P<0.05).At 42 days of age,there was no significant difference in slaughter performance between the trial groups and the control group(P>0.05).3)Compared with the control group,the crude fat metabolic rate of each trial group increased significantly at 14 and 42 days of age(P<0.05).At14 days of age,the crude protein metabolic rate of trial group II decreased significantly(P<0.05),but there was no significant difference between trial group II and I(P>0.05).At 42 days of age,the metabolic rate of calcium in each trial group decreased significantly(P<0.05),and that of phosphorus in trial group II decreased significantly(P<0.05),but there was no significant difference from trial group I(P>0.05).Part 2:Effects of insoluble fiber on intestinal health of broilersAt the age of 14 days and 42 days,two broilers of appropriate size were selected for each repeat group.After slaughter,muscle stomach,glandular stomach,duodenum,jejunum and ileum were collected,their contents were removed,weighed accurately,and the relative weight,relative length and relative width of duodenum,jejunum and ileum were measured and calculated.At the same time,the intestinal segments of duodenum,jejunum and ileum were taken to measure the villus height,recess depth and villus height/recess depth(V/C value)of each intestinal segment of broilers.In addition,the contents of ileum and cecum were taken to determine the intestinal microbial diversity.The experimental results showed as follows: 1)Compared with the control group,the relative weight of muscle stomach of broilers at 14 and 42 days of age in each trial group increased significantly(P<0.05),the relative weight of glandular stomach of broilers at 14 days of age increased significantly(P<0.05),and the relative weight of glandular stomach of broilers at 42 days of age decreased significantly(P<0.05).There was no significant difference in most indexes of small intestine segments of broilers in each trial group at 14 and 42 days of age compared with the control group(P>0.05).The relative length and width of jejunum in trial group II at 14 days of age and the relative length of jejunum in trial group I at 42 days of age increased significantly(P<0.05).2)Compared with the control group,at 14 days of age,the villus height of jejunum and ileum in each trial group increased significantly(P<0.05),the recess depth of each segment of small intestine decreased significantly(P<0.05),and the V/C value of each segment of small intestine increased significantly(P<0.05).At 42 days of age,the villus height of ileum in each trial group increased significantly(P<0.05),the recess depth of duodenum and ileum decreased significantly(P<0.05),and the V/C value of each segment of small intestine increased significantly(P<0.05).3)Compared with the control group,there was no significant change in the diversity and richness of ileum microorganisms in each trial group at 14 and 42 days of age(P>0.05),and the richness of cecal flora in broilers at 14 days of age was significantly increased(P<0.05).At 14 days of age,the abundance of Bacteroidetes decreased,the abundance of Firmicutes increased,and the abundance of Lactobacillus increased significantly(P<0.05).At 42 days of age,the abundance of Actinomycetes and Proteobacteria decreased,and the abundance of Firmicutes increased.The abundance of Candidatus_Arthromitus and Lactobacillus in the cecum decreased,while the abundance of Enterococcus in the ileum and cecum and Butyricicoccus coccus in the cecum increased.Part 3:Effects of insoluble fiber on lipid metabolism in broiler liverAt 14 and 42 days of age,one broiler of suitable size was selected for each replicate,and blood samples were collected under wing to determine serum lipid metabolism related parameters.The broilers were slaughtered,and their livers were removed to determine the relative weight of livers,and the m RNA expression levels of genes related to lipid metabolism in livers were determined by fluorescence quantitative method.The experimental results showed as follows: 1)Compared with the control group,the contents of serum cholesterol(TC),liver cholesterol(TC)and triglyceride(TG)in each trial group decreased significantly at 14 days of age(P<0.05);The relative weight of liver in trial group Ⅱ decreased significantly(P<0.05),but there was no significant difference between trial group Ⅱ and Ⅰ(P>0.05).At 42 days of age,the contents of TC,TG,HDLC and LDLC in serum of trial groups showed no significant difference(P>0.05).TG content in liver of trial group Ⅰ was significantly lower than that of trial group Ⅱ and control group(P<0.05),TC content was significantly lower than that in trial group Ⅱ((P<0.05),and there was no significant difference compared with control group(P>0.05).2)Compared with the control group,the m RNA expressions of Stearoyl-Co A Desaturase1(SCD1),Malate Dehydrogenase(ME)and Apolipoprotein A(Apo A)in liver of broilers in trial groups I and II at 14 days of age were significantly decreased(P<0.05).The m RNA expressions of Lipoprotein Esterase(LPL),Triglyceride Lipase(ATGL),Carnitine Palmityl Transferase1(CPT1),Peroxisome Proliferator Activated Receptorγ(PPARγ)and Apolipoprotein B(Apo B)were significantly increased(P<0.05).At 42 days of age,the m RNA expression levels of SCD1 in liver of trial groups were significantly decreased(P<0.05),while the m RNA expression levels of CPT1,PPARγ and Apo B were significantly increased(P<0.05).In conclusion: Insoluble fiber can reduce crude the protein metabolic rate of broilers at 14 days of age,so it had a negative effect on the performance of broilers.But it can improve the performance of broilers by increasing crude protein metabolic rate and improving intestinal health of broilers at late growth stage.It has little effect on the whole production performance.In addition,insoluble fiber can also reduce fat deposition in the liver and body of broilers by improving fat utilization rate and regulating the expression of genes related to lipid metabolism in the liver,and the effect on young broilers is more significant.