Effects Of Short And Medium Chain Fatty Acids In Diet And Drinking Water On Growth Performance And Gut Health Of Broiler Chickens

Two trials were conducted to study the effects of the addition of two short and medium chain fatty acids products in diet(MSCT)or drinking water(SCT)on the growth performance and gut health compared to antibiotic promoter in broilers.Experiment 1:Effects of short chain fatty acids in diet and drinking water on growth performance,litter quality and gut microbiota of broiler chickens.A study was conducted to compare the effect of antibiotic growth promoters(AGP)with two Products MSCT and SCT.MSCT is an encapsulated butyrates,encapsulated MCFAs,organic acids(mainly sorbic acid)and phenolic compound,it is a gut health enhancer.SCT is a mixture organic acids(formic,acetic,and their salts),it is a drinking water product for water quality and chicken health.Single factor test design was adopted.There were 5 treatments including a basal diet(Control),AGP group(basal diet+ 20 ppm Colistin sulphate),MSCT group(basal diet+ MSCT 1.5g/kg in Phases 1;MSCT 1.0g/kg in phases 2 respectively),SCT group(basal diet+SCT 0.5mL/L in Phase 1;SCT 1.5 mL/L in Phase 2 respectively,only three days per week),MSCT + SCT group(basal diet+ MSCT 1.5g/kg + SCT 0.5mL/L in Phase 1;MSCT 1.0g/kg + SCT 1.5 mL/L in Phase 2,only three days per week).A total of 1,500 day-old chicks(Ross,male)were randomly allocated into 5 treatments with 15 replicates of 20 chicks each.The experiment period was 42 days.The results showed that MSCT improved(P<0.05)feed conversion ratio(FCR)compared with Control and AGP in Phase 1(P<0.05),but weight gain was not affected(P>0.05).At d21,adding SCT or MSCT+SCT significantly reduced(P<0.05)the footpad lesion score and the litter moisture compared with Control.Furthermore,AGP or MSCT had the highest gut microbial diversity,evenness and richness of bands,with the lowest in the group with MSCT+SCT.In conclusion,the present study indicated that birds fed MSCT had a comparative advantage of the growth performance of the chickens in dl to 21.MSCT can be used as an alternative to AGP in broiler chicken diets.Experiment 2:Research the optimum level of short chain fatty acids in drinking water of broiler chickens.The objective of this study was to investigate the optimum level of Product SCT as an alternative to antibiotic growth promoters in broiler chickens.A single factor trial design was adopted.There were 5 treatments including a basal diet(Control),AGP group(basal diet+Zinc bacitracin 40mg/kg),SCT groups with the addition of SCT at 0.5mL/L,1.OmL/L,1.5mL/L respectively.A total of 1,6501-day-old chicks(Ross,male)were randomly allocated into 5 treatments with 15 replicates of 22 chicks each.The experiment was divided into 2 phases containing dl to 21(Phase 1)and d22 to 42(Phase 2).The results showed that compared to the control group,the three levels of SCT groups significantly increased the body weight(BW)in 21d and 42d,the body weight gain(BWG)in 1-21d and 1-42d,the 0.5 and 1.5 mL/L B groups significantly increased BWG in 22-42d(P<0.01).Compared to the control group,0.5 and 1.5 mL/L SCT groups significantly reduced the FCR in 1-21d,22-42d and 1-42d(P<0.01).Compared to AGP group,the 0.5 mL/L B groups significantly reduced the FCR in 22-42d and 1-42d,1.5 mL/L SCT groups significantly reduced the FCR in 1-42d(P<0.01).Compared to the control and AGP groups,the 1.0 and 1.5 mL/L B groups significantly increased the feed intake(FI)in 1-21d,and the three levels of SCT groups significantly increased the FI in 22-42d and 1-42d(P<0.01).Compared to the control group,the AGP and the 1.0 mL/L SCT groups significantly reduced the litter moisture in 42d(P=0.002).Compared to the AGP group,the 0.5 mL/L SCT group increased the litter moisture in 42d.Compared to the control and the AGP groups,the 1.0 and 1.5ml/L SCT groups significantly reduced the score of foot pad dermatitis(FPD)in 21d,and the 1.5 mL/L SCT group significantly reduced the score of FPD in 42d,while the 0.5 and 1.0 mL/L SCT groups significantly increased the score of FPD in 42d(P<0.01).At 21d and 42d,the villus height and villus height/crypt depth(V/C)were no significant difference among groups in duodenum.Compared to the control group,the three levels of SCT groups very significantly reduced the crypt depth in 42d.Compared to the AGP group,the 1.5ml/L SCT group very significantly reduced the crypt depth in 42d(P=0.006).Compared to the control group,the 0.5 and 1.5 mL/L SCT groups significantly reduced the villus height in jejunum in 21d(P=0.003),and AGP and 1.OmL/L SCT groups have no effect on it.Compared to the AGP and control groups,1.5 mL/L SCT groups significantly reduced the crypt depth in jejunum in 21d(P=0.047),the 1.0 and 1.5 mL/L SCT groups very significantly reduced the crypt depth in jejunum in 42d(P<0.01).Compared to the control group,the three levels of SCT groups very significantly increased V/C in jejunum in 42d(P=0.002),but have no effect on the 21d.Compared to the AGP group,the 1.0 and 1.5 mL/L SCT groups significantly increased the villus height in ileum in 21d(P=0.016),but have no effect on the 42d.Compared to the control and AGP groups,the 1.0 and 1.5 mL/L SCT groups very significantly reduced crypt depth in ileum in 42d(P<0.01),but have no effect on the 21d.Compared to the control group,the 1.0 and 1.5 mL/L SCT groups very significantly increased V/C in ileum in 42d(P=0.032),but have no effect on the 21d.Compared with control group,the three levels of SCT groups significantly increased the relative expression of Caludin-1 genes in jejunum in 21d(P=0.050),but have no effect on the 42d.The relative expression of Occludin and ZO-1 genes had no significant difference in jejunum among groups.Compared to the control group,there were no siginificant difference between the Aerobic bacteria,Lactobacillus,Bifidobacterium in crop in 21 d and 42d.Compared to the control and AGP groups,1.5mL/L B group very siginificantly reduced the number of Enterobacteriaceae in crop in 42d(P=0.054),but have no effect on 21d.Compared to the control group,there were no siginificant difference between the Lactobacillus and Bifidobacterium in cecum in 21d and 42d.Compared to the AGP group,the three levels of SCT groups significantly increased the total aerobic bacteria.Compared to the control group,0.5mL/L SCT group significantly increased the total aerobic bacteria(P=0.030).Compared to the control and AGP groups,0.5mL/L and 1.5mL/L SCT groups very significantly reduced the number of Enterobacteriaceae in cecum in 42d.Compared to the AGP group,1.OmL/L SCT groups very significantly reduced the number of Enterobacteriaceae in cecum in 42d(P=0.002).but had no effect on the number of total aerobic bacteria and Enterobacteriaceae in cecum in 21d.All groups didn't have effect on the microbial diversity in cecum at 21d.At 21d,there were no significant differences observed in the proportions of volatile fatty acid.At 42d,1.5mL/L SCT group greatly increased the proportion of acetate(P=0.004),but didn't have effect on proportion of propionate and butyrate.The results showed that the product SCT can significantly improve the growth performance of broiler chickens,with a better addition of 0.5 and 1.5 mL/L.The AGP and 1.0 mL/L SCT groups can improve the litter moisture.The 1.5ml/L SCT group can reduce the score of FPD.The three levels of SCT groups can improve the intestinal morphology.1.5ml/L SCT groups can reduce the amount of E.coli in the crop and cecum,and 0.5 mL/L SCT group can also reduce the number of E.coli in the cecum.The 1.5ml/L SCT group can increase the proportion of propionic acid in the cecum.Therefore,all three levels of product SCT can alternative antibiotics.In conclusion:1.The addition of(1-21d,1.5g/kg;22-42d 1.0g/kg)improved feed conversion ratio(FCR)(P<0.05).2.The addition of SCT at 0.5,1.0 and 1.5 mL/L in drinking water improved the broiler growth performance,and decreased the litter water content and FPD scores of broilers.The appropriate dosage is 0.5mL/L based on the growth performance,or 1.5 mL/L based on the litter quality or FPD of broilers.3.The addition of SCT at 0.5,1.0,1.5 mL/L in drinking water significantly improved the intestinal morphology,with the increased of the relative expression of Caludin-1 genes in jejunum,while with the decreased the number of Enterobacteriaceae and the increased of the proportion of propionic acid.4.The two kinds of short and medium chain fatty acids products can be used as an alternative to antibiotics.