Effects And Regulatory Mechanism Of Dietary Sodium Acetate Supplementation On Fat Deposition In White Feather Broilers

Acetic acid,is the main product of carbohydrate fermentation by anaerobic bacteria in the colon of animals.It plays an important role in regulating animal fat metabolism.The purpose of this experiment was to investigate the effect of different levels of sodium acetate on fat deposition in white feather broilers.A total of 192 Ross 308,7-day-old of white feather broilers with healthy and similar weight were randomly divided into 4 treatment groups with 6 replicates in each group and 8 broilers in each replicate.Each group was fed with basic diet（control group）and diet supplemented with different levels of sodium acetate（0.1%,0.3%,0.5%）for 35 days.The results show that:1)There were no significant differences in average daily gain,average daily feed intake,feed weight ratio,slaughter rate,semi clean bore rate,full clean bore rate,chest muscle rate and leg muscle rate among the groups（P>0.05）.2)The addition of sodium acetate significantly increased the abdominal fat deposition of white feather broilers.The abdominal fat rate of 0.1%,0.3%and 0.5%sodium acetate group was significantly higher than that of the control group（P<0.05）.3)There was no significant difference in chest muscle brightness（L）,yellowness（b）,drip loss and pH value(pH_24h)24 hours after slaughter among the groups（P>0.05）.The chest muscle pH 45min in the 0.5%sodium acetate group was significantly lower than that in the control group（P<0.05）,and there was no significant difference between the 0.1%and0.3%sodium acetate groups and the control group（P>0.05）;The redness of pectoral muscle in sodium acetate group was significantly higher than that in control group（P<0.05）;The hydraulic power of pectoral muscle system in 0.3%and 0.5%sodium acetate group was significantly higher than that in the control group（P<0.05）,and there was no significant difference between 0.1%sodium acetate group and the control group（P>0.05）.There was no significant difference in ph45min,ph24h,brightness,redness,yellowness and dripping loss of leg muscle among the groups（P>0.05）,but the hydraulic power of leg muscle system in 0.3%and 0.5%sodium acetate group was significantly higher than that in the control group（P<0.05）,and there was no significant difference between 0.1%sodium acetate group and the control group（P>0.05）.4)There was no significant difference in blood glucose（Glu）content and aspartate aminotransferase（AST）activity among the groups（P>0.05）.The content of triglyceride（TG）in serum of 0.5%sodium acetate group was significantly higher than that of the control group（P<0.05）,and there was no significant difference between 0.1%and 0.3%sodium acetate groups and the control group（P>0.05）;The content of total cholesterol（TC）in serum of 0.1%and 0.5%sodium acetate group was significantly higher than that of the control group（P<0.05）,and there was no significant difference between 0.3%sodium acetate group and the control group（P>0.05）;The content of serum low density lipoprotein cholesterol（LDL-C）in 0.1%,0.3%and 0.5%sodium acetate group was significantly higher than that in the control group（P<0.05）;The content of serum high density lipoprotein cholesterol（HDL-C）in 0.5%sodium acetate group was significantly higher than that in the control group（P<0.05）,and there was no significant difference between 0.1%and 0.3%sodium acetate group and the control group（P>0.05）.The content of serum ALT in 0.5%sodium acetate group was significantly higher than that in the control group（P<0.05）,and there was no significant difference between 0.1%and 0.3%sodium acetate group and the control group（P>0.05）.5)The contents of TG and TC in liver increased with the increase of sodium acetate in diet.The content of TG increased significantly in 0.5%addition group（P<0.05）,and the content of TC increased significantly in 0.3%and 0.5%sodium acetate addition group（P<0.05）.Sodium acetate significantly increased the mRNA expression of LPL,L-FABP,Fas,ACC and SREBP-1c in the liver of white feather broilers（P<0.05）;The addition of0.1%,0.3%and 0.5%sodium acetate significantly increased the mRNA expression of Fas（P<0.05）;The mRNA expression of ACC increased significantly with the addition of 0.1%and 0.5%sodium acetate（P<0.05）,but there was no significant difference with the addition of 0.3%sodium acetate（P>0.05）;The addition of 0.3%and 0.5%sodium acetate significantly increased the mRNA expression of LPL（P<0.05）;The addition of 0.5%sodium acetate significantly increased the mRNA expression of L-FABP（P<0.05）.6)A certain amount of sodium acetate can affect the microbial structure in the intestine of white feather broilers.Under the experimental conditions,the addition of 0.3%sodium acetate significantly reduced Chao1 and observed＿species、PD＿whole＿Tree index（P<0.05）;The addition of 0.5%sodium acetate reduced PD＿whole＿Tree index（P<0.05）.The results of PCo A,PCA and anoism showed that the addition of 0.1%sodium acetate did not significantly change the intestinal microbiota structure（P>0.05）,but the addition of 0.3%and 0.5%sodium acetate significantly affected the intestinal microbiota structure of white feather broilers（P<0.05）.At the phylum level,the addition of 0.5%sodium acetate significantly reduced the abundance of Firmicutes（P<0.05）,increased the abundance of Bacteroidetes（P<0.05）,and decreased the ratio of Firmicutes/Bacteroidetes（P<0.05）.At the genus level,the composition of flora structure between 0.1%sodium acetate group and control group was similar,and there was no significant difference（P>0.05）.The addition of0.3%sodium acetate significantly increased the abundance of Bacteroides and negative bacilli（P<0.05）.The addition of 0.5%sodium acetate significantly increased the relative abundance of other mycobacteria and negative bacilli（P<0.05）,and decreased the relative abundance of Clostridium erysipelas（P<0.05）.The above results showed that the addition of a certain amount of sodium acetate could significantly affect the structure and composition of intestinal microbiota in white feather broilers,and increase the relative abundance of Bacteroidetes,other mycobacteria and Bacteroides that ferment undigested carbohydrates and proteins to produce organic acids or short chain fatty acids;However,the increase of sodium acetate also increased the abundance of pathogenic negative bacteria,which may have a negative impact on the intestinal health of white feather broilers.Different levels of sodium acetate had no significant effect on microbial metabolites SCFAs.In conclusion,the addition of sodium acetate in diet had no significant effect on the growth performance and slaughter performance of white feather broilers,but significantly promoted the body fat deposition of white feather broilers.The addition of low-dose sodium acetate can improve the meat quality,and has no significant effect on serum biochemical indexes and microbial flora structure.However,the addition of high-dose sodium acetate can significantly increase the abdominal fat rate and blood lipid level of white feather broilers,which may have a negative impact on intestinal health.