Background:Alternative feedstuffs may contribute to reducing feed costs of pig production.But these feedstuffs are typically rich in fiber and resistant starch(RS).Dietary fibers and RS are fermented in the gastrointe...Background:Alternative feedstuffs may contribute to reducing feed costs of pig production.But these feedstuffs are typically rich in fiber and resistant starch(RS).Dietary fibers and RS are fermented in the gastrointestinal tract(GIT)and modulate the microbial community.Certain microbes in the GIT can promote host health,depending on the type of fermentation substrates available.In this study,six alternative feedstuffs(three starchy:Okinawan sweet potato,OSP;yam,and taro,and three fibrous:wheat millrun,WMR;barley brewers grain,BBG;and macadamia nut cake,MNC)were evaluated for their in vitro digestibility and fermentation characteristics and their effects on pig’s hindgut microbial profile.After 2 steps of enzymatic digestion assay,residues were fermented using fresh pig feces as microbial inoculum,and gas production was recorded periodically for 72 h and modeled for fermentation kinetics.After fermentation,the residual liquid phase was analyzed for short-chain fatty acid(SCFA),and the solid phase was used to determine the nutrient’s digestibility and microbial community.Results:In vitro ileal digestibility of dry matter and gross energy was higher in starchy than fibrous feedstuffs.Total gas and SCFA production were significantly higher(P<0.001)in starchy feedstuffs than fibrous feedstuffs.Both acetate and propionate production was significantly higher(P<0.001)in all starchy feedstuffs than BBG and MNC;WMR was in between.Overall alpha diversity was not significantly different within and between starchy and fibrous feedstuffs.Beta diversity(measured using bray Curtis dissimilarity distance)of starchy feedstuffs was significantly different(P<0.005)than fibrous feedstuffs.Conclusion:Starchy feedstuffs acted as a substrate to similar types of microbes,whereas fibrous feedstuffs resulted in a more diverse microbial population.Such alternative feedstuffs may exert comparable beneficial effects,thus may be included in swine diets to improve gut health.展开更多
Dietary fibers(DF)contain an abundant amount of energy,although the mammalian genome does not encode most of the enzymes required to degrade them.However,a mutual dependence is developed between the host and symbiotic...Dietary fibers(DF)contain an abundant amount of energy,although the mammalian genome does not encode most of the enzymes required to degrade them.However,a mutual dependence is developed between the host and symbiotic microbes,which has the potential to extract the energy present in these DF.Dietary fibers escape digestion in the foregut and are fermented in the hindgut,producing shortchain fatty acids(SCFA)that after the microbial ecology in the gastrointestinal tract(GIT)of pigs.Most of the carbohydrates are fermented in the proximal part,allowing protein fermentation in the distal part,resulting in colonic diseases.The structures of resistant starch(RS),arabinoxylan(AX),and β-glucan(βG)are complex;hence,makes their way into the hindgut where these are fermented and provide energy substrates for the colonic epithelial cells.Different microbes have different preferences of binding to different substrates.The RS,AX and βG act as a unique substrate for the microbes and modify the relative composition of the gut microbial community.The granule dimension and surface area of each substrate are different,which influences the penetration capacity of microbes.Arabinose and xylan are 2 different hemicelluloses,but arabinose is substituted on the xylan backbone and occurs in the form of AX.Fermentation of xylan produces butyrate primarily in the small intestine,whereas arabinose produces butyrate in the large intestine.Types of RS and forms of βG also exert beneficial effects by producing different metabolites and modulating the intestinal microbiota.Therefore,it is important to have information of different types of RS,AX and(3 G and their roles in microbial modulation to get the optimum benefits of fiber fermentation in the gut.This review provides relevant information on the similarities and differences that exist in the way RS,AX,and βG are fermented,and their positive and negative effects on SCFA production and gut microbial ecology of pigs.These insights will help nutritionists to develop dietary strategies that can modulate specific SCFA production and promote beneficial microbiota in the GIT of swine.展开更多
Exploring and evaluating alternative feed ingredients to be used in swine diet is essential due to highly variable cost and limited availability of conventional feed ingredients. Tubers and agro-industrial coproducts ...Exploring and evaluating alternative feed ingredients to be used in swine diet is essential due to highly variable cost and limited availability of conventional feed ingredients. Tubers and agro-industrial coproducts could provide the basis for producing affordable swine feed. However, information on the nutritional value of these potential alternative feedstuffs is necessary while considering their use in swine feeding program. Four tubers(purple sweet potato [PSP], okinawan sweet potato, taro and cassava) and 3 coproducts(okara, wheat millrun [WMR] and barley brewers grain [BBG]) were analyzed for their proximate nutrients, starch, fibers and gross energy(GE) content. Two independent in vitro studies were carried out for tubers and coproducts to determine their nutrients digestibility using a 3-step enzymatic assay(which mimics the digestion occurring in the gastrointestinal tract of swine) with 9 replicates of each sample digested in 3 batches equally. All replicate samples were used to determine in vitro dry matter digestibility(IVDDM) while 2 replicates from each batch were used to determine in vitro GE digestibility(IVDGE). Among tubers, CP content was the highest in taro(8.8%) and the lowest in cassava(3.7%), while CP content among coproducts was the highest in okara(22.7%) and the lowest in WMR(11.8%). Ether extract content among tubers ranged from 1.1% to 2.8%. The GE content among tubers, ranged from 4,134 to 4,334 kcal/kg whereas among coproducts it ranged from 4,270 to 4,794 kcal/kg. Among tubers, IVDDM for PSP was significantly higher(86.8%, P < 0.001) than taro(70.3%). Among coproducts, IVDDM of okara(74.1%) was significantly higher(P < 0.05) than BBG(61.3%). In conclusion,both tubers and coproducts can be used as a partial substitute of conventional energy feedstuffs in swine diets as these are rich in GE and other nutrients and are fairly digestible.展开更多
基金supported by USDA National Institute for Food and Agriculture,Hatch-Multistate fund,managed by the College of Tropical Agriculture and Human Resources,University of Hawaii at Manoa,Honolulu,HI,USA.
文摘Background:Alternative feedstuffs may contribute to reducing feed costs of pig production.But these feedstuffs are typically rich in fiber and resistant starch(RS).Dietary fibers and RS are fermented in the gastrointestinal tract(GIT)and modulate the microbial community.Certain microbes in the GIT can promote host health,depending on the type of fermentation substrates available.In this study,six alternative feedstuffs(three starchy:Okinawan sweet potato,OSP;yam,and taro,and three fibrous:wheat millrun,WMR;barley brewers grain,BBG;and macadamia nut cake,MNC)were evaluated for their in vitro digestibility and fermentation characteristics and their effects on pig’s hindgut microbial profile.After 2 steps of enzymatic digestion assay,residues were fermented using fresh pig feces as microbial inoculum,and gas production was recorded periodically for 72 h and modeled for fermentation kinetics.After fermentation,the residual liquid phase was analyzed for short-chain fatty acid(SCFA),and the solid phase was used to determine the nutrient’s digestibility and microbial community.Results:In vitro ileal digestibility of dry matter and gross energy was higher in starchy than fibrous feedstuffs.Total gas and SCFA production were significantly higher(P<0.001)in starchy feedstuffs than fibrous feedstuffs.Both acetate and propionate production was significantly higher(P<0.001)in all starchy feedstuffs than BBG and MNC;WMR was in between.Overall alpha diversity was not significantly different within and between starchy and fibrous feedstuffs.Beta diversity(measured using bray Curtis dissimilarity distance)of starchy feedstuffs was significantly different(P<0.005)than fibrous feedstuffs.Conclusion:Starchy feedstuffs acted as a substrate to similar types of microbes,whereas fibrous feedstuffs resulted in a more diverse microbial population.Such alternative feedstuffs may exert comparable beneficial effects,thus may be included in swine diets to improve gut health.
基金supported by USDA National Institute for Food and Agriculture,Hatch/Smith-Lever Project HAW02030-HCollege of Tropical Agriculture and Human Resources,University of Hawaii at Manoa,Honolulu,HI USA
文摘Dietary fibers(DF)contain an abundant amount of energy,although the mammalian genome does not encode most of the enzymes required to degrade them.However,a mutual dependence is developed between the host and symbiotic microbes,which has the potential to extract the energy present in these DF.Dietary fibers escape digestion in the foregut and are fermented in the hindgut,producing shortchain fatty acids(SCFA)that after the microbial ecology in the gastrointestinal tract(GIT)of pigs.Most of the carbohydrates are fermented in the proximal part,allowing protein fermentation in the distal part,resulting in colonic diseases.The structures of resistant starch(RS),arabinoxylan(AX),and β-glucan(βG)are complex;hence,makes their way into the hindgut where these are fermented and provide energy substrates for the colonic epithelial cells.Different microbes have different preferences of binding to different substrates.The RS,AX and βG act as a unique substrate for the microbes and modify the relative composition of the gut microbial community.The granule dimension and surface area of each substrate are different,which influences the penetration capacity of microbes.Arabinose and xylan are 2 different hemicelluloses,but arabinose is substituted on the xylan backbone and occurs in the form of AX.Fermentation of xylan produces butyrate primarily in the small intestine,whereas arabinose produces butyrate in the large intestine.Types of RS and forms of βG also exert beneficial effects by producing different metabolites and modulating the intestinal microbiota.Therefore,it is important to have information of different types of RS,AX and(3 G and their roles in microbial modulation to get the optimum benefits of fiber fermentation in the gut.This review provides relevant information on the similarities and differences that exist in the way RS,AX,and βG are fermented,and their positive and negative effects on SCFA production and gut microbial ecology of pigs.These insights will help nutritionists to develop dietary strategies that can modulate specific SCFA production and promote beneficial microbiota in the GIT of swine.
基金supported by the USDA, National Institute for Food and Agriculture, Hatch Project HAW02030-H, managed by the College of Tropical Agriculture and Human Resources, University of Hawaii at Manoa
文摘Exploring and evaluating alternative feed ingredients to be used in swine diet is essential due to highly variable cost and limited availability of conventional feed ingredients. Tubers and agro-industrial coproducts could provide the basis for producing affordable swine feed. However, information on the nutritional value of these potential alternative feedstuffs is necessary while considering their use in swine feeding program. Four tubers(purple sweet potato [PSP], okinawan sweet potato, taro and cassava) and 3 coproducts(okara, wheat millrun [WMR] and barley brewers grain [BBG]) were analyzed for their proximate nutrients, starch, fibers and gross energy(GE) content. Two independent in vitro studies were carried out for tubers and coproducts to determine their nutrients digestibility using a 3-step enzymatic assay(which mimics the digestion occurring in the gastrointestinal tract of swine) with 9 replicates of each sample digested in 3 batches equally. All replicate samples were used to determine in vitro dry matter digestibility(IVDDM) while 2 replicates from each batch were used to determine in vitro GE digestibility(IVDGE). Among tubers, CP content was the highest in taro(8.8%) and the lowest in cassava(3.7%), while CP content among coproducts was the highest in okara(22.7%) and the lowest in WMR(11.8%). Ether extract content among tubers ranged from 1.1% to 2.8%. The GE content among tubers, ranged from 4,134 to 4,334 kcal/kg whereas among coproducts it ranged from 4,270 to 4,794 kcal/kg. Among tubers, IVDDM for PSP was significantly higher(86.8%, P < 0.001) than taro(70.3%). Among coproducts, IVDDM of okara(74.1%) was significantly higher(P < 0.05) than BBG(61.3%). In conclusion,both tubers and coproducts can be used as a partial substitute of conventional energy feedstuffs in swine diets as these are rich in GE and other nutrients and are fairly digestible.
