Medium-chain fatty acids and monoglycerides as feed additives for pig production:towards gut health improvement and feed pathogen mitigation

Ongoing challenges in the swine industry,such as reduced access to antibiotics and virus outbreaks(e.g.,porcine epidemic diarrhea virus,African swine fever virus),have prompted calls for innovative feed additives to support pig production.Medium-chain fatty acids(MCFAs)and monoglycerides have emerged as a potential option due to key molecular features and versatile functions,including inhibitory activity against viral and bacterial pathogens.In this review,we summarize recent studies examining the potential of MCFAs and monoglycerides as feed additives to improve pig gut health and to mitigate feed pathogens.The molecular properties and biological functions of MCFAs and monoglycerides are first introduced along with an overview of intervention needs at different stages of pig production.The latest progress in testing MCFAs and monoglycerides as feed additives in pig diets is then presented,and their effects on a wide range of production issues,such as growth performance,pathogenic infections,and gut health,are covered.The utilization of MCFAs and monoglycerides together with other feed additives such as organic acids and probiotics is also described,along with advances in molecular encapsulation and delivery strategies.Finally,we discuss how MCFAs and monoglycerides demonstrate potential for feed pathogen mitigation to curb disease transmission.Looking forward,we envision that MCFAs and monoglycerides may become an important class of feed additives in pig production for gut health improvement and feed pathogen mitigation.

Evaluation of dynamic effects of dietary medium-chain monoglycerides on performance,intestinal development and gut microbiota of broilers in large-scale production

Medium-chain monoglycerides(MG)have been reported to affect the productive performance,gut microbiota and health of broiler chickens reared in ideal experimental conditions at home and abroad.However,the effects of MG on performance,intestinal development and gut microbiota of chickens in large-scale farms during different feed stages remain unknown.The present study was conducted on a modern farm with a total of 12,000 yellow feathered broiler chicks that were randomly allotted to 2groups(1000 chicks/replicate,6 replicates/group)for a 70-day trial.The control group(CON group)received a basal diet,and the treated group(MG group)was fed a basal diet containing 300 mg/kg mixed MG.The results revealed that dietary MG significantly(P<0.05)increased the body weight and average feed intake,but notably reduced the feed conversion and mortality of chickens in large-scale production during the starter phase.The villus height of the duodenum in the MG group at 1,2 and 7 wk of age increased notably,and the villus height to crypt depth ratio at 1,2,5 and 10 wk of age was improved.Dietary MG decreased the serum insulin content of chickens at 5,7 and 10 wk of age,and decreased the serum lipopolysaccharide at 3 and 7 wk of age.The triglyceride level of chickens at 3,5 and 10 wk of age and the low-density lipoprotein cholesterol level of chickens at 7 and 10 wk of age in the MG group decreased notably,while the high-density lipoprotein cholesterol increased significantly.Moreover,MG supplementation selectively increased the relative abundance of genus Bacteroides(family Bacteroidaceae)and Lachnospiraceae_NK4A136_group,but decreased the content of genus Rikenellaceae_RC9_gut_group,Collinsella and family Barnesiellaceae in the cecum of chickens at 3,7 and 10 wk of age.Conclusively,these findings showed that dietary MG notably enhanced chicken performance,health and feed nutrient utilization at early ages by regulating gut microbiota,intestinal development and serum biochemical indices.

Inhibition of African swine fever virus in liquid and feed by medium-chain fatty acids and glycerol monolaurate

Background:The ongoing African swine fever virus(ASFv)epidemic has had a major impact on pig production globally and biosecurity efforts to curb ASFv infectivity and transmission are a high priority.It has been recently identified that feed and feed ingredients,along with drinking water,can serve as transmission vehicles and might facilitate transboundary spread of ASFv.Thus,it is important to test the antiviral activity of regulatory compatible,antiviral feed additives that might inhibit ASFv infectivity in feed.One promising group of feed additive candidates includes medium-chain fatty acids(MCFA)and monoglyceride derivatives,which are known to disrupt the lipid membrane surrounding certain enveloped viruses and bacteria.Results:The antiviral activities of selected MCFA,namely caprylic,capric,and lauric acids,and a related monoglyceride,glycerol monolaurate(GML),to inhibit ASFv in liquid and feed conditions were investigated and suitable compounds and inclusion rates were identified that might be useful for mitigating ASFv in feed environments.Antiviral assays showed that all tested MCFA and GML inhibit ASFv.GML was more potent than MCFA because it worked at a lower concentration and inhibited ASFv due to direct virucidal activity along with one or more other antiviral mechanisms.Dose-dependent feed experiments further showed that sufficiently high GML doses can significantly reduce ASFv infectivity in feed in a linear manner in periods as short as 30 min,as determined by infectious viral titer measurements.Enzyme-linked immunosorbent assay(ELISA)experiments revealed that GML treatment also hinders antibody recognition of the membrane-associated ASFv p72 structural protein,which likely relates to protein conformational changes arising from viral membrane disruption.Conclusion:Together,the findings in this study indicate that MCFA and GML inhibit ASFv in liquid conditions and that GML is also able to reduce ASFv infectivity in feed,which may help to curb disease transmission.

Production of mono-, di-, and triglycerides from waste fatty acids through esterification with glycerol

Currently monoglyceride and diglyceride are representing important products, as they have numerous applications such as modifying agents in food and pharmaceutical industries. In this work, the production of these economically value added compounds by estrifying the fatty acids with the glycerol is presented. Effects of various reaction parameters were optimized to obtain high yield of mono, di- and triglycerids. The effects of temperature (180℃ to 260℃), ZnCl2 catalyst concentration (0.1%, 0.2%, 0.3%), glycerol to fatty acids molar ratio (1:1, 1:2, 1:3, 3:1), agitation speeds (200, 500, 1000 rpm), type of reaction system (opened and closed) and type of fatty acids including oleic and palmatic acids on esterification efficiency of fatty acids were investigated. The optimum conditions of esterification reaction were at temperature 195℃, molar ratio 1:1, amount of catalyst 0.3% Zncl2, and agitation 500 rpm. Analysis of yield showed that at the optimum conditions mondi and triglycerids were produced in high purity, up to 99%. Infrared spectroscopy IR and thin layer chromatograph TLC proved that the final product contains mono, di- and triglycerides.

油脂甘油醇解法合成硬脂酸单甘酯合成条件研究

硬脂酸单甘酯(glycerol monostearate,GM)是一种重要的多元醇型非离子表面活性剂。油脂甘油醇解法是制备单硬脂酸甘油酯最重要的工业方法,在油脂醇解反应中,脂肪酰基在油脂分子和加入的游离甘油分子之间重新排列,生成单甘酯和二甘酯。研究油脂甘油醇解法的合成条件对产物单甘脂含量的影响,对企业通过技术改进以提高生产效益、降低能耗和节约生产成本,具有积极的指导作用。本文通过对投料比、催化剂种类、催化剂量、反应温度、反应时长5个因素进行实验和分析,发现:①酯交换法合成单酯,反应转化率随甘油∶氢化油的摩尔比先增大后减小。当甘油∶氢化油的摩尔比为2∶1时,粗酯中单甘酯含量最高;②催化剂采用NaOH的催化活性相对较高,其次,KaOH的催化活性也比较高;③酯交换法合成单酯,反应转化率随NaOH加入量的增加先增大后减小,催化剂占氢化油质量的0.4%时粗酯中单甘酯含量最大;④酯交换法合成单酯,反应转化率随反应温度的升高先增大后减小,235℃时单甘酯含量最大;⑤酯交换法合成单酯,单甘酯反应转化率随反应时长的延长先增大后减小,2.5 h时单甘酯含量最大;⑥通过正交考察酯交换法合成单酯最佳反应条件为催化剂采用NaOH,添加量为氢化油质量的0.4%、反应温度235℃、反应时长2 h,其反应单酯含量可以达到40.2%。