Background: 1-3, 1-6 β-glucan derived from Baker’s yeast (Saccharomyces cerevisiae) has been widely studied for its immune stimulatory capabilities and safety. Previous studies found β-glucan to have efficacy at re...Background: 1-3, 1-6 β-glucan derived from Baker’s yeast (Saccharomyces cerevisiae) has been widely studied for its immune stimulatory capabilities and safety. Previous studies found β-glucan to have efficacy at reducing incidence of URTIs as well as being a low risk for negative side effects. The current study aimed to examine the effects of yeast β-glucan (Angel Yeast) on cold and flu incidences and symptoms in healthy adults. Methods: Two hundred and thirty-one males and females aged 18 to 65 years old supplemented with either β-glucan or a placebo for 3-months. Participants completed a general health questionnaire every 4 weeks and in addition, if participants experienced any cold or flu symptoms, these were recorded daily (along with severity) until resolved or up to 2 weeks. Results: Supplementation with β-glucan reduced the self-reported severity of sore throats and improved sleep quality compared to the placebo group. Conclusions: Yeast β-glucan supplementation appears to be able to help reduce certain symptoms experienced during a cold or flu episode and is safe and well tolerated.展开更多
Nitrogen,one of the most crucial nutrients present in grapes and musts,plays a key role in yeast activities during alcoholic fermentation.Such influences are imposed on yeast growth and fermentation performances inclu...Nitrogen,one of the most crucial nutrients present in grapes and musts,plays a key role in yeast activities during alcoholic fermentation.Such influences are imposed on yeast growth and fermentation performances including the formation of secondary metabolites.Saccharomyces cerevisiae,the main yeast responsible for fermentation,has been studied extensively regarding nitrogen impacts.On the other hand,a similar study for non-Saccharomyces yeasts,whose contributions to winemaking have gradually been acknowledged,remains to be fully explored,with a few studies being reported.This review starts by discussing nitrogen impacts on non-Saccharomyces yeast growth and fermentation kinetics in different case scenarios,then proceeds to summarize the nitrogen preferences of individual yeast strains with regulation mechanisms elucidated by recent studies.Detailed discussions on the influences on the production of volatile compounds and proposed pathways therein are made,followed by future work suggested as the final section.In summarizing the nitrogen impacts on non-Saccharomyces yeasts throughout alcoholic fermentation,this review will be helpful in obtaining a more comprehensive view on these non-conventional wine yeasts in terms of nutrient requirements and corresponding volatile production.Research gaps will therefore be elucidated for future research.展开更多
The budding yeast Saccharomyces cerevisiae is a powerful model system for studying the cell polarity establishment.The cell polarization process is regulated by signaling molecules,which are initially distributed in t...The budding yeast Saccharomyces cerevisiae is a powerful model system for studying the cell polarity establishment.The cell polarization process is regulated by signaling molecules,which are initially distributed in the cytoplasm and then recruited to a proper location on the cell membrane in response to spatial cues or spontaneously.Polarization of these signaling molecules involves complex regulation,so the mathematical models become a useful tool to investigate the mechanism behind the process.In this review,we discuss how mathematical modeling has shed light on different regulations in the cell polarization.We also propose future applications for the mathematical modeling of cell polarization and morphogenesis.展开更多
Sorghum beer or dolo is part of the eating habits of part of the population of Dédougou because of its low price compared with industrial beers. Its production is an ancestral tradition that uses traditional equi...Sorghum beer or dolo is part of the eating habits of part of the population of Dédougou because of its low price compared with industrial beers. Its production is an ancestral tradition that uses traditional equipment and gives dolo organoleptic properties that are not found in industrial beers. The production process involves several stages, including fermentation, which itself comprises natural lactic fermentation followed by alcoholic fermentation using traditional yeasts, which are not controlled in any way. The general aim of this study is to assess the microbiological quality of these fermentative yeasts in the town of Dédougou, in order to contribute to the health safety of the population and the promotion of these local beers. Twenty samples of fermenting yeast were analyzed according to ISO standards, to isolate enterobacteria, total and faecal coliforms according to standard procedures for isolating these micro-organisms. The isolated strains were identified using the API20E gallery. Microbiological analyses revealed the presence of 51.17% enterobacteria, 45.38% total coliforms and 3.45% thermotolerant coliforms. We counted 40% Escherichia coli, 20% Enterobacter cloacae, 20% Klebsiella pneumoniae and 20% Klebsiella spp. All the strains detected are capable of surviving in hostile conditions and could harm the quality of the dolo, consumer health and cause real collective food poisoning in the town of Dédougou. This enabled us to assess the microbial quality of these yeasts and to propose more suitable measures for producing and preserving dolo under hygienic conditions to protect consumer health.展开更多
Background Intestinal inflammation is the main risk factor causing intestinal barrier dysfunction and lipopolysaccharide(LPS)can trigger inflammatory responses in various eukaryotic species.Yeast hydrolysate(YH)posses...Background Intestinal inflammation is the main risk factor causing intestinal barrier dysfunction and lipopolysaccharide(LPS)can trigger inflammatory responses in various eukaryotic species.Yeast hydrolysate(YH)possesses multibiological effects and is received remarkable attention as a functional ingredient for improving growth performance and promoting health in animals.However,there is still inconclusive on the protective effects of dietary YH supplementation on intestinal barrier of piglets.This study was conducted to investigate the attenuate effects of YH supplementation on inflammatory responses and intestinal barrier injury in piglets challenged with LPS.Methods Twenty-four piglets(with an average body weight of 7.42±0.34 kg)weaned at 21 days of age were randomly assigned to one of two dietary treatments(12 replications with one pig per pen):a basal diet or a basal diet containing YH(5 g/kg).On the 22nd d,6 piglets in each treatment were intraperitoneally injected with LPS at 150μg/kg BW,and the others were injected with the same amount of sterile normal saline.Four hours later,blood samples of each piglet were collected and then piglets were euthanized.Results Dietary YH supplementation increased average daily feed intake and average daily gain(P<0.01),decreased the ratio of feed intake to gain of piglets(P sponse,evidenced by the increase o=0.048).Lipopolysaccharide(LPS)injection induced systemic inflammatory ref serum concentrations of haptoglobin(HP),adrenocorticotropic hormone(ACTH),cortisol,and interleukin-1β(IL-1β).Furthermore,LPS challenge resulted in inflammatory intestinal damage,by up-regulation of the protein or mRNA abundances of tumor necrosis factor-α(TNF-α),IL-1β,toll-like receptors 4(TLR4)and phosphor-nuclear factor-κB-p65(p-NFκB-p65)(P<0.01),and down-regulation of the jejunal villus height,the protein and mRNA abundances of zonula occludens-1(ZO-1)and occludin(OCC;P<0.05)in jejunal mucosa.Dietary YH supplementation decreased the impaired effects of ACTH,cortisol,HP,IL-1βand diamine oxidase in serum(P<0.05).Moreover,YH supplementation also up-regulated the jejunal villus height,protein and mRNA abundances of ZO-1 and OCC(P<0.05),down-regulated the mRNA expressions of TNF-αand IL-1βand the protein abundances of TNF-α,IL-1β,TLR4 and p-NFκB-p65 in jejunal mucosa in LPS-challenged pigs(P<0.01).Conclusion Yeast hydrolysate could attenuate inflammatory response and intestinal barrier injury in weaned piglets challenged with LPS,which was associated with the inhibition of TLR4/NF-κB signaling pathway activation.展开更多
Yeasts play a critical role in the flavor formation of dry-cured ham.In this study,41 yeast isolates from the dry-cured ham at different processing stages were evaluated for their technological properties.Debaryomyces...Yeasts play a critical role in the flavor formation of dry-cured ham.In this study,41 yeast isolates from the dry-cured ham at different processing stages were evaluated for their technological properties.Debaryomyces hansenii was the most dominant yeast and has been detected at each phase of dry-cured ham,followed by Candida zeylanoides which was mainly detected in salting phase.Yarrowia bubula and Yarrowia alimentaria were found at the first two-phase of dry-cured ham.All isolates of yeast showed enzymatic activities against milk protein and tributyrin,while only 4 strains displayed proteolytic activity on meat protein.Yeast strains were grown in a meat model medium and volatile compounds were identified.The result showed that inoculated yeast strains could promote the production of volatiles and there were significant differences among strains.D.hansenii S25 showed the highest production of volatile compounds,followed by the strain C.zeylanoides C4.D.hansenii S25 was the highest producer of alcohols showing the highest production of benzeneethanol and 3-(methylthio)-1-propanol.Based on OAV and PLS analysis,D.hansenii S25 was strongly correlated with overall flavor and key volatile compounds of dry-cured ham,which could be selected as potential starter cultures.展开更多
Dairy production plays an integral part in supporting smallholder farmers’ livelihoods. The desire to increase the number of dairy cattle is not feasible due to the reduced output of feed resources occasioned by clim...Dairy production plays an integral part in supporting smallholder farmers’ livelihoods. The desire to increase the number of dairy cattle is not feasible due to the reduced output of feed resources occasioned by climate change. Consequently, the need to increase productivity per cow is inevitable. Conventional protein supplements are costly;hence, the need to explore affordable nutrientdense alternative feed resources. Liquid brewers’ yeast (LBY), a by-product of the brewing industry, is a rich protein supplement in dairy production. This study aimed to assess the dairy farming conditions and utilization levels of LBY as a feed supplement in Githunguri Sub-county, Kiambu. Semi-structured questionnaires were administered to 457 dairy farmers in a cross-sectional survey. The findings revealed that most farmers (94.2%) fed their cattle on established forage/fodder and crop residues with supplementation. Even though 53.1% of the respondents were aware of the use of LBY, only 30.6% utilized it to supplement dairy cows, most of whom (96.0%) used it fresh without preservation. Membership in farmers’ organizations increased awareness of LBY (r = 0.732). Principal component analysis indicated that the benefits of using LBY outweigh the challenges involved with a loading matrix of 0.891 - 0.954 and 0.681 - 0.807, respectively. The low adoption and use levels of LBY as a source of protein supplements were due to low awareness. There is a need for concerted efforts by stakeholders in the industry to increase farmers’ knowledge base on the utilization and effectiveness of LBY in dairy production.展开更多
Background There is a growing search for natural feed additives to alleviate the deleterious effects of coccidia infection in poultry production.This study aimed to investigate the effect of enzymatically treated yeas...Background There is a growing search for natural feed additives to alleviate the deleterious effects of coccidia infection in poultry production.This study aimed to investigate the effect of enzymatically treated yeast(ETY) on the growth performance,nutrient digestibility,intestinal morphology,antioxidative status,and cecal mucosa cytokines of coccidia-challenged broiler chickens.Methods From d 1 to 14 post hatching,480 broiler chickens were allocated to 3 corn-soybean meal-based experimental diets with increasing concentrations of ETY(0,1,or 2 g/kg).The experiment was designed as a randomized complete block design with body weight(BW) used as a blocking factor.On d 14 post hatching,the birds were re-randomized within each of the 3 experimental diets.Each of the 3 diet groups was split into a challenge or no-challenge group.This resulted in a 3 × 2 factorial arrangement of treatments.The coccidia challenge was administered on d 15 by an oral gavage.Results Dietary ETY improved(P < 0.05) the G:F of birds on d 21 regardless of the challenge state and linearly increased(P < 0.01) the apparent ileal digestibility of dry matter(DM),nitrogen,and gross energy(GE).The coccidia challenge decreased(P < 0.05) BW gain and feed intake of broiler chickens and reduced(P < 0.01) the total tract retention of DM,GE,and nitrogen.The coccidia challenge increased(P < 0.01) the mRNA gene expression of TNFα,IL-1β,IL-10,and IL-6 in the cecal mucosa.There was a tendency(P ne = 0.08) for ETY to linearly reduce IL-1β expression.Additionally,ETY supplementation increased(P < 0.05) the geexpression of OCLN.Serum catalase increased(P < 0.05) with dietary ETY in broiler chickens on d 21.Dietary ETY linearly increased(P < 0.05) the ileal villus height to crypt depth ratio,and ileal goblet cell density in broiler chickens.The ileal and excreta oocyst counts decreased(P < 0.01) with increasing supplementation of dietary ETY in coccidia-challenged broiler chickens on d 21.Conclusions Dietary ETY enhanced nutrient utilization and augmented intestinal development in broiler chickens.However,dietary ETY did not completely attenuate the adverse effects of a coccidia challenge in broiler chickens.展开更多
The aim of this study was to use a meta-analytic approach to evaluate the effect of commercially available yeast probiotic “Actisaf<sup>®</sup>; Sc 47” (Saccharomyces cerevisiae CNCM I-4407)...The aim of this study was to use a meta-analytic approach to evaluate the effect of commercially available yeast probiotic “Actisaf<sup>®</sup>; Sc 47” (Saccharomyces cerevisiae CNCM I-4407) produced and marketed by Phileo by Lesaffre on milk performance in dairy cows. Data from 22 trials including 17 with parallel designs and 5 with cross-over designs were collected, and only data with parallel designs were analyzed. From those trials, 4 are published and 13 are from technical reports. In total, 34 comparisons and 1074 dairy cows met the criteria for inclusion in the final analysis of milk yield (MY). For energy corrected milk (ECM), six trials with 12 comparisons and 476 dairy cows met the criteria for inclusion in the final analysis. Because the data are from different trials with different conditions, the statistical model defined includes the fixed effect of the treatment (with vs. without Actisaf<sup>®</sup> Sc 47) and the random effect of the trial. The meta-analysis showed a moderate heterogeneity for MY and ECM. The random effect meta-analysis showed an estimated mean difference +1.72 kg/d [95% confidence interval (CI): 1.01 to 2.44] and +2.45 kg/d (95% CI: 1.73 to 3.17) for MY and ECM respectively, in favour of Actisaf<sup>®</sup><sup> </sup>Sc 47. The analysis of data without trials conducted under heat stress conditions showed positive effect of Actisaf<sup>®</sup> Sc 47. The random effect meta-analysis showed an estimated mean difference of +1.69 kg/d [95% CI: 1.24 to 2.14] and +2.92 kg/d (95% CI: 2.45 to 3.40) for MY and ECM respectively, in favour of Actisaf<sup>®</sup> Sc 47. These observations provide strong evidence that this commercially available yeast probiotic can significantly improve milk performances of dairy cows under different conditions.展开更多
Peanut(Arachis hypogaea L.)is a thermophilic crop,and low temperature leads to a significant reduction in annual yields.Despite a few cold tolerant germplasms or cultivars have been discovered and developed,molecular ...Peanut(Arachis hypogaea L.)is a thermophilic crop,and low temperature leads to a significant reduction in annual yields.Despite a few cold tolerant germplasms or cultivars have been discovered and developed,molecular mechanisms governing peanut cold tolerance is poorly understood.Identification of keys genes involved in cold tolerance is the first step to address the underlying mechanism.In this study,we isolated and characterized 157 genes with potentials to confer cold tolerance in peanut by using a yeast functional screening system.GO(Gene ontology)and KEGG(Kyoto encyclopedia of genes and genomes)enrichment analysis of these genes revealed that ribosome and photosynthesis proteins might play essential roles in peanut cold response.Transcriptome results indicated that 60 cold tolerance candidate genes were significantly induced or depressed by low temperature.qRT-PCR analysis demonstrated that several candidate genes could be also regulated by salt or drought stress.Individual overexpression of two UDP-glycosyltransferases(AhUGT2 and AhUGT268)in transgenic yeast cells could enhance their tolerance to multiple abiotic stress.In conclusion,this study advances our understanding of the mechanisms associated with the cold stress responses in peanut,and offers valuable gene resources for genetic improvement of abiotic stress tolerance in crops.展开更多
Higher levels of acetaldehyde in beer are one of the major concerns in the current beer industry.Yeast produces acetaldehyde during alcoholic fermentation,and its modification significantly affects beer flavor and qua...Higher levels of acetaldehyde in beer are one of the major concerns in the current beer industry.Yeast produces acetaldehyde during alcoholic fermentation,and its modification significantly affects beer flavor and quality.A different mutant strain with lower acetaldehyde production and improved ethanol tolerance was constructed using the ARTP-ALE mutagenesis strategy with 4-methylpyrazole-disulfiram.As a result of the mutation,the alcohol dehydrogenase activity of the mutant strain decreased to about 71.22%of that of the wild-type strain.At the same time,the fermentation properties and genetic stability of the newly screened strain showed slight differences from the wild-type strain,and there were no safety concerns regarding industrial use of the mutant strain.展开更多
文摘Background: 1-3, 1-6 β-glucan derived from Baker’s yeast (Saccharomyces cerevisiae) has been widely studied for its immune stimulatory capabilities and safety. Previous studies found β-glucan to have efficacy at reducing incidence of URTIs as well as being a low risk for negative side effects. The current study aimed to examine the effects of yeast β-glucan (Angel Yeast) on cold and flu incidences and symptoms in healthy adults. Methods: Two hundred and thirty-one males and females aged 18 to 65 years old supplemented with either β-glucan or a placebo for 3-months. Participants completed a general health questionnaire every 4 weeks and in addition, if participants experienced any cold or flu symptoms, these were recorded daily (along with severity) until resolved or up to 2 weeks. Results: Supplementation with β-glucan reduced the self-reported severity of sore throats and improved sleep quality compared to the placebo group. Conclusions: Yeast β-glucan supplementation appears to be able to help reduce certain symptoms experienced during a cold or flu episode and is safe and well tolerated.
基金supported by grants from the National Natural Science Foundation of China(32172340)。
文摘Nitrogen,one of the most crucial nutrients present in grapes and musts,plays a key role in yeast activities during alcoholic fermentation.Such influences are imposed on yeast growth and fermentation performances including the formation of secondary metabolites.Saccharomyces cerevisiae,the main yeast responsible for fermentation,has been studied extensively regarding nitrogen impacts.On the other hand,a similar study for non-Saccharomyces yeasts,whose contributions to winemaking have gradually been acknowledged,remains to be fully explored,with a few studies being reported.This review starts by discussing nitrogen impacts on non-Saccharomyces yeast growth and fermentation kinetics in different case scenarios,then proceeds to summarize the nitrogen preferences of individual yeast strains with regulation mechanisms elucidated by recent studies.Detailed discussions on the influences on the production of volatile compounds and proposed pathways therein are made,followed by future work suggested as the final section.In summarizing the nitrogen impacts on non-Saccharomyces yeasts throughout alcoholic fermentation,this review will be helpful in obtaining a more comprehensive view on these non-conventional wine yeasts in terms of nutrient requirements and corresponding volatile production.Research gaps will therefore be elucidated for future research.
文摘The budding yeast Saccharomyces cerevisiae is a powerful model system for studying the cell polarity establishment.The cell polarization process is regulated by signaling molecules,which are initially distributed in the cytoplasm and then recruited to a proper location on the cell membrane in response to spatial cues or spontaneously.Polarization of these signaling molecules involves complex regulation,so the mathematical models become a useful tool to investigate the mechanism behind the process.In this review,we discuss how mathematical modeling has shed light on different regulations in the cell polarization.We also propose future applications for the mathematical modeling of cell polarization and morphogenesis.
文摘Sorghum beer or dolo is part of the eating habits of part of the population of Dédougou because of its low price compared with industrial beers. Its production is an ancestral tradition that uses traditional equipment and gives dolo organoleptic properties that are not found in industrial beers. The production process involves several stages, including fermentation, which itself comprises natural lactic fermentation followed by alcoholic fermentation using traditional yeasts, which are not controlled in any way. The general aim of this study is to assess the microbiological quality of these fermentative yeasts in the town of Dédougou, in order to contribute to the health safety of the population and the promotion of these local beers. Twenty samples of fermenting yeast were analyzed according to ISO standards, to isolate enterobacteria, total and faecal coliforms according to standard procedures for isolating these micro-organisms. The isolated strains were identified using the API20E gallery. Microbiological analyses revealed the presence of 51.17% enterobacteria, 45.38% total coliforms and 3.45% thermotolerant coliforms. We counted 40% Escherichia coli, 20% Enterobacter cloacae, 20% Klebsiella pneumoniae and 20% Klebsiella spp. All the strains detected are capable of surviving in hostile conditions and could harm the quality of the dolo, consumer health and cause real collective food poisoning in the town of Dédougou. This enabled us to assess the microbial quality of these yeasts and to propose more suitable measures for producing and preserving dolo under hygienic conditions to protect consumer health.
基金supported by the National Key Research and Development Program of China(2018YFD0500605)the Key Research and Development Program of Sichuan Province(2021YFYZ0008)the Sichuan Pig Innovation Team of National Modern Agricultural Industry Technology System of China(scsztd-2020-08-11)。
文摘Background Intestinal inflammation is the main risk factor causing intestinal barrier dysfunction and lipopolysaccharide(LPS)can trigger inflammatory responses in various eukaryotic species.Yeast hydrolysate(YH)possesses multibiological effects and is received remarkable attention as a functional ingredient for improving growth performance and promoting health in animals.However,there is still inconclusive on the protective effects of dietary YH supplementation on intestinal barrier of piglets.This study was conducted to investigate the attenuate effects of YH supplementation on inflammatory responses and intestinal barrier injury in piglets challenged with LPS.Methods Twenty-four piglets(with an average body weight of 7.42±0.34 kg)weaned at 21 days of age were randomly assigned to one of two dietary treatments(12 replications with one pig per pen):a basal diet or a basal diet containing YH(5 g/kg).On the 22nd d,6 piglets in each treatment were intraperitoneally injected with LPS at 150μg/kg BW,and the others were injected with the same amount of sterile normal saline.Four hours later,blood samples of each piglet were collected and then piglets were euthanized.Results Dietary YH supplementation increased average daily feed intake and average daily gain(P<0.01),decreased the ratio of feed intake to gain of piglets(P sponse,evidenced by the increase o=0.048).Lipopolysaccharide(LPS)injection induced systemic inflammatory ref serum concentrations of haptoglobin(HP),adrenocorticotropic hormone(ACTH),cortisol,and interleukin-1β(IL-1β).Furthermore,LPS challenge resulted in inflammatory intestinal damage,by up-regulation of the protein or mRNA abundances of tumor necrosis factor-α(TNF-α),IL-1β,toll-like receptors 4(TLR4)and phosphor-nuclear factor-κB-p65(p-NFκB-p65)(P<0.01),and down-regulation of the jejunal villus height,the protein and mRNA abundances of zonula occludens-1(ZO-1)and occludin(OCC;P<0.05)in jejunal mucosa.Dietary YH supplementation decreased the impaired effects of ACTH,cortisol,HP,IL-1βand diamine oxidase in serum(P<0.05).Moreover,YH supplementation also up-regulated the jejunal villus height,protein and mRNA abundances of ZO-1 and OCC(P<0.05),down-regulated the mRNA expressions of TNF-αand IL-1βand the protein abundances of TNF-α,IL-1β,TLR4 and p-NFκB-p65 in jejunal mucosa in LPS-challenged pigs(P<0.01).Conclusion Yeast hydrolysate could attenuate inflammatory response and intestinal barrier injury in weaned piglets challenged with LPS,which was associated with the inhibition of TLR4/NF-κB signaling pathway activation.
基金the financial support of Guizhou Province Science and Technology Plan Project(QKHZC[2020]1Y152)the Guizhou High-level Innovative Talent Training Project(Qianke Cooperation Platform Talent number[2016]5662)Guizhou Science and Technology Innovation Talent Team of Ecological Characteristic Meat Products(QKHPTRC[2020]5004).
文摘Yeasts play a critical role in the flavor formation of dry-cured ham.In this study,41 yeast isolates from the dry-cured ham at different processing stages were evaluated for their technological properties.Debaryomyces hansenii was the most dominant yeast and has been detected at each phase of dry-cured ham,followed by Candida zeylanoides which was mainly detected in salting phase.Yarrowia bubula and Yarrowia alimentaria were found at the first two-phase of dry-cured ham.All isolates of yeast showed enzymatic activities against milk protein and tributyrin,while only 4 strains displayed proteolytic activity on meat protein.Yeast strains were grown in a meat model medium and volatile compounds were identified.The result showed that inoculated yeast strains could promote the production of volatiles and there were significant differences among strains.D.hansenii S25 showed the highest production of volatile compounds,followed by the strain C.zeylanoides C4.D.hansenii S25 was the highest producer of alcohols showing the highest production of benzeneethanol and 3-(methylthio)-1-propanol.Based on OAV and PLS analysis,D.hansenii S25 was strongly correlated with overall flavor and key volatile compounds of dry-cured ham,which could be selected as potential starter cultures.
文摘Dairy production plays an integral part in supporting smallholder farmers’ livelihoods. The desire to increase the number of dairy cattle is not feasible due to the reduced output of feed resources occasioned by climate change. Consequently, the need to increase productivity per cow is inevitable. Conventional protein supplements are costly;hence, the need to explore affordable nutrientdense alternative feed resources. Liquid brewers’ yeast (LBY), a by-product of the brewing industry, is a rich protein supplement in dairy production. This study aimed to assess the dairy farming conditions and utilization levels of LBY as a feed supplement in Githunguri Sub-county, Kiambu. Semi-structured questionnaires were administered to 457 dairy farmers in a cross-sectional survey. The findings revealed that most farmers (94.2%) fed their cattle on established forage/fodder and crop residues with supplementation. Even though 53.1% of the respondents were aware of the use of LBY, only 30.6% utilized it to supplement dairy cows, most of whom (96.0%) used it fresh without preservation. Membership in farmers’ organizations increased awareness of LBY (r = 0.732). Principal component analysis indicated that the benefits of using LBY outweigh the challenges involved with a loading matrix of 0.891 - 0.954 and 0.681 - 0.807, respectively. The low adoption and use levels of LBY as a source of protein supplements were due to low awareness. There is a need for concerted efforts by stakeholders in the industry to increase farmers’ knowledge base on the utilization and effectiveness of LBY in dairy production.
文摘Background There is a growing search for natural feed additives to alleviate the deleterious effects of coccidia infection in poultry production.This study aimed to investigate the effect of enzymatically treated yeast(ETY) on the growth performance,nutrient digestibility,intestinal morphology,antioxidative status,and cecal mucosa cytokines of coccidia-challenged broiler chickens.Methods From d 1 to 14 post hatching,480 broiler chickens were allocated to 3 corn-soybean meal-based experimental diets with increasing concentrations of ETY(0,1,or 2 g/kg).The experiment was designed as a randomized complete block design with body weight(BW) used as a blocking factor.On d 14 post hatching,the birds were re-randomized within each of the 3 experimental diets.Each of the 3 diet groups was split into a challenge or no-challenge group.This resulted in a 3 × 2 factorial arrangement of treatments.The coccidia challenge was administered on d 15 by an oral gavage.Results Dietary ETY improved(P < 0.05) the G:F of birds on d 21 regardless of the challenge state and linearly increased(P < 0.01) the apparent ileal digestibility of dry matter(DM),nitrogen,and gross energy(GE).The coccidia challenge decreased(P < 0.05) BW gain and feed intake of broiler chickens and reduced(P < 0.01) the total tract retention of DM,GE,and nitrogen.The coccidia challenge increased(P < 0.01) the mRNA gene expression of TNFα,IL-1β,IL-10,and IL-6 in the cecal mucosa.There was a tendency(P ne = 0.08) for ETY to linearly reduce IL-1β expression.Additionally,ETY supplementation increased(P < 0.05) the geexpression of OCLN.Serum catalase increased(P < 0.05) with dietary ETY in broiler chickens on d 21.Dietary ETY linearly increased(P < 0.05) the ileal villus height to crypt depth ratio,and ileal goblet cell density in broiler chickens.The ileal and excreta oocyst counts decreased(P < 0.01) with increasing supplementation of dietary ETY in coccidia-challenged broiler chickens on d 21.Conclusions Dietary ETY enhanced nutrient utilization and augmented intestinal development in broiler chickens.However,dietary ETY did not completely attenuate the adverse effects of a coccidia challenge in broiler chickens.
文摘The aim of this study was to use a meta-analytic approach to evaluate the effect of commercially available yeast probiotic “Actisaf<sup>®</sup>; Sc 47” (Saccharomyces cerevisiae CNCM I-4407) produced and marketed by Phileo by Lesaffre on milk performance in dairy cows. Data from 22 trials including 17 with parallel designs and 5 with cross-over designs were collected, and only data with parallel designs were analyzed. From those trials, 4 are published and 13 are from technical reports. In total, 34 comparisons and 1074 dairy cows met the criteria for inclusion in the final analysis of milk yield (MY). For energy corrected milk (ECM), six trials with 12 comparisons and 476 dairy cows met the criteria for inclusion in the final analysis. Because the data are from different trials with different conditions, the statistical model defined includes the fixed effect of the treatment (with vs. without Actisaf<sup>®</sup> Sc 47) and the random effect of the trial. The meta-analysis showed a moderate heterogeneity for MY and ECM. The random effect meta-analysis showed an estimated mean difference +1.72 kg/d [95% confidence interval (CI): 1.01 to 2.44] and +2.45 kg/d (95% CI: 1.73 to 3.17) for MY and ECM respectively, in favour of Actisaf<sup>®</sup><sup> </sup>Sc 47. The analysis of data without trials conducted under heat stress conditions showed positive effect of Actisaf<sup>®</sup> Sc 47. The random effect meta-analysis showed an estimated mean difference of +1.69 kg/d [95% CI: 1.24 to 2.14] and +2.92 kg/d (95% CI: 2.45 to 3.40) for MY and ECM respectively, in favour of Actisaf<sup>®</sup> Sc 47. These observations provide strong evidence that this commercially available yeast probiotic can significantly improve milk performances of dairy cows under different conditions.
基金This work was supported by a grant from the National Natural Science Foundation of China(No.32170278)the Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences(No.CAAS-ASTIP-2021-OCRI)the Earmarked fund for China Agricultural Research System(CARS-13).
文摘Peanut(Arachis hypogaea L.)is a thermophilic crop,and low temperature leads to a significant reduction in annual yields.Despite a few cold tolerant germplasms or cultivars have been discovered and developed,molecular mechanisms governing peanut cold tolerance is poorly understood.Identification of keys genes involved in cold tolerance is the first step to address the underlying mechanism.In this study,we isolated and characterized 157 genes with potentials to confer cold tolerance in peanut by using a yeast functional screening system.GO(Gene ontology)and KEGG(Kyoto encyclopedia of genes and genomes)enrichment analysis of these genes revealed that ribosome and photosynthesis proteins might play essential roles in peanut cold response.Transcriptome results indicated that 60 cold tolerance candidate genes were significantly induced or depressed by low temperature.qRT-PCR analysis demonstrated that several candidate genes could be also regulated by salt or drought stress.Individual overexpression of two UDP-glycosyltransferases(AhUGT2 and AhUGT268)in transgenic yeast cells could enhance their tolerance to multiple abiotic stress.In conclusion,this study advances our understanding of the mechanisms associated with the cold stress responses in peanut,and offers valuable gene resources for genetic improvement of abiotic stress tolerance in crops.
基金Supported by Heilongjiang Natural Science Foundation Joint Guide Project(LH2019C022)。
文摘Higher levels of acetaldehyde in beer are one of the major concerns in the current beer industry.Yeast produces acetaldehyde during alcoholic fermentation,and its modification significantly affects beer flavor and quality.A different mutant strain with lower acetaldehyde production and improved ethanol tolerance was constructed using the ARTP-ALE mutagenesis strategy with 4-methylpyrazole-disulfiram.As a result of the mutation,the alcohol dehydrogenase activity of the mutant strain decreased to about 71.22%of that of the wild-type strain.At the same time,the fermentation properties and genetic stability of the newly screened strain showed slight differences from the wild-type strain,and there were no safety concerns regarding industrial use of the mutant strain.