| Medium Chain Fatty Acid(MCFA)is containing 6 to 12 carbon atoms of carbon chain saturated fatty acid,including Caproic acid,Octanoic acid,Decanoic Acid and Lauric acid.MCFA and glycerol produced by the esterification reaction to triglyceride is called medium chain fatty acid triglycerides(MCT).MCFA/MCT has some characteristics,such as a short carbon chain,low molecular weight,polar and high water solubility,etc.,so,in the organism,digestion,absorption,transport and metabolism of Medium chain fatty acid is different from that of long chain fatty acids(LCFA).Due to its unique chemical structure and physicochemical properties,MCFA has good antibacterial effect in vitro and in vivo,and has obvious effect on controlling piglet digestive tract diseases.Moreover,due to the effect on change of intestinal structure and its unique role of energy supply,MCFA has the obvious effect on increasing animal weight.However,the effects of MCFA on piglets under high ambient temperature have not been reported until now.This study attempted to assess bacteriostatic effect of medium chain fatty acids(MCFA)on pathogens and beneficial bacteria in vitro and in vivo,investigate its effects on growth performance of weaning piglets and its effects on heat shock protein mRNA levels,immune function and intestinal flora,and MCFA containing feed additive was developed and clinical promotion and effect were evaluated in this study,which could provide the theory and production basis for its wide application in animal production.Experiment 1,the Effect of Medium-chain Fatty Acid on Bacteriostasis in Vitro.The experiment was designed to research on the effect of medium-chain fatty acid on bacteriostasis in vitro.The effect of MCFA’s resisting E.coli,Salmonella,Steptococcus and Lactobacillus in vitro was measured by drug sensitive test.The result shows MCFA can minimize pathogenic bacterium growth,especially the E.coli and Salmonella but not Lactobacillus.Experiment 2,the Effect of the Medium-chain Fatty Acid on the Productive Performance of Weaning Piglets under High Ambient Temperature.The weaning piglets were selected from one pig farm in Anhui and divided into three equal groups by random from July to August,2013.In each group,three repeatitions were set.The three groups were fed with basic ration,basic ration and 0.1%medium-chain fatty acid,basic ration and 0.3%medium-chain fatty acid,respectively.The result showed that the daily weight gain of the group fed with basic ration and 0.3%medium-chain fatty acid improved by 9.65 percent while F/G reduced by 12.8 percent and diarrhea rate reduced by53.8 percent compared to the control group under the same feeding conditions and breeding environment.The result indicates 0.3%medium-chain fatty acid addition in basic ration will promote growth of weaning piglet and serve as theoretical underpinning for its application and promotion in pig industry.Experiment 3,the Effect of Medium-chain Fatty Acid on HSP mRNA Level of Weaning Piglet under High Ambient Temperature.The weaning piglets were selected from one pig farm in Anhui and divided into three equal groups by random from July to August,2013.In each group,three repeatitions were set.The three groups were fed with basic ration,basic ration and 0.1%medium-chain fatty acid,basic ration and 0.3%medium-chain fatty acid,respectively.The result showed that the group fed with basic ration and 0.1%or 0.3%medium-chain fatty acid got higher blood and tissue HSP mRNA expression compared to the control under higher temperature breeding environment.Beside the 0.3%group got a better effect(P<0.05).The result indicates 0.3%medium-chain fatty acid addition in basic ration will have a good effect on improving anti-stress ability and serve as theoretical underpinning for its application and promotion in pig industry.Experiment 4,the Effect of the Medium-chain Fatty Acid on the Intestinal Flora Fauna and Immune Function of Weaning Piglets under High Ambient Temperature.The weaning piglets were selected from one pig farm in Anhui and divided into three equal groups by random from July to August,2013.In each group,three repeatitions were set.The three groups were fed with basic ration,basic ration and 0.1%medium-chain fatty acid,basic ration and 0.3%medium-chain fatty acid,respectively.The result showed that the group fed with basic ration and 0.1%or 0.3%medium-chain fatty acid got markedly higher amount of lactobacillus and bifidobacterium and lower amount of E.coli and enterococcus in faeces compared to the control group under the same feeding conditions and breeding environment.Beside the 0.3%group got a better effects(P<0.05).The group fed with basic ration and 0.1%or 0.3%medium-chain fatty acid has no effects on T lymphocyte transformation of pig peripheral blood mononuclear and splenocytes and IL-2contents.The result indicates 0.3%medium-chain fatty acid addition in basic ration will have good effect on improving bacteria and serve as theoretical underpinning for its application and promotion in pig industry.Feed additives,chain fatty acids as the main ingredients,was demonstrationly applied of large scale pig farms in Hainan,Guangxi,Chongqing,Jiangsu,Anhui and other provinces,20000 sows and more than 100000 piglets were used in the application of feed additives.The results demonstrated that chain fatty acids could promote the growth of piglets,improve the survival rate,shorten the sow childbirth time,reduce the weak young,improve feed conversion rate and economic benefit.The effects of additives on sows and piglets are more obvious under high ambient temperature. |
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