Ruminants utilize a wide variety of dietary substrates that are not digestible by the mammals, through microbial fermentation taking place in the rumen. Recent advanced molecular based approaches have allowed the char...Ruminants utilize a wide variety of dietary substrates that are not digestible by the mammals, through microbial fermentation taking place in the rumen. Recent advanced molecular based approaches have allowed the characterization of rumen microbiota and its compositional changes under various treatment conditions.However, the knowledge is still limited on the impacts of variations in the rumen microbiota on host biology and function. This review summarizes the information to date on host-microbial interactions in the rumen and how we can apply such information to seek the opportunities to enhance the animal performance through manipulating the rumen function.展开更多
[Objective]This experiment was conducted to investigate the effects of heat stress on microbial numbers in rumen fluid of dairy cows during different lactating periods by real-time PCR.[Methods]A 2 ×3 crossover d...[Objective]This experiment was conducted to investigate the effects of heat stress on microbial numbers in rumen fluid of dairy cows during different lactating periods by real-time PCR.[Methods]A 2 ×3 crossover design was used and eighteen healthy Chinese Holstein cows were selected.The cows were allocated into three periods based on their parity,average days in milk,and milk yield:early lactation(postpartum 15 to 100 days),mid-lactation(postpartum 112 to 175 days)and late lactation(postpartum 200 to 230 days),and six cows in each period.A self-control trial between heat stress period and non-heat stress period was used based on temperature and humidity index(THI)measurement on site.[Results]The results showed as follows:compared with non-heat stress period,heat stress significantly increased the microbial numbers in early lactation,the Ruminococcus flavefaciens number in different lactation and Bacteroides succinogenes number in early and mid-lactation(P 〈0.01).The total bacteria and Ruminococcus albus numbers in mid-and late lactation and Bacteroides succinogenes number in late lactation were decreased significantly by heat stress(P 〈0.01).There were strong correlation between THI and the numbers of total bacteria(P 〈0.01),anaerobic fungi(P 〈0.05),Ruminococcus albus(P 〈0.01)and Ruminococcus flavefaciens(P 〈0.05)in rumen fluid of dairy cows in early lactation,but the correlation between THI and these indexes in mid-and late lactation were poor.[Conclusion]It is indicated that the rumen microbial numbers in early lactation are more sensitive to heat stress.展开更多
Background Ferulic acid esterase(FAE)-secreting Lactiplantibacillus plantarum A1(Lp A1)is a promising silage inoculant due to the FAE’s ability to alter the plant cell wall structure during ensiling,an action that is...Background Ferulic acid esterase(FAE)-secreting Lactiplantibacillus plantarum A1(Lp A1)is a promising silage inoculant due to the FAE’s ability to alter the plant cell wall structure during ensiling,an action that is expected to improve forage digestibility.However,little is known regarding the impacts of Lp A1 on rumen microbiota.Our research assessed the influences of Lp A1 in comparison to a widely adopted commercial inoculant Lp MTD/1 on alfalfa’s ensilage,in vitro rumen incubation and microbiota.Results Samples of fresh and ensiled alfalfa treated with(either Lp A1 or Lp MTD/1)or without additives(as control;CON)and ensiled for 30,60 and 90 d were used for fermentation quality,in vitro digestibility and batch culture study.Inoculants treated silage had lower(P<0.001)pH,acetic acid concentration and dry matter(DM)loss,but higher(P=0.001)lactic acid concentration than the CON during ensiling.Compared to the CON and Lp MTD/1,silage treated with Lp A1 had lower(P<0.001)aNDF,ADF,ADL,hemicellulose,and cellulose contents and higher(P<0.001)free ferulic acid concentration.Compared silage treated with Lp MTD/1,silage treated with Lp A1 had significantly(P<0.01)improved ruminal gas production and digestibility,which were equivalent to those of fresh alfalfa.Realtime PCR analysis indicated that Lp A1 inoculation improved the relative abundances of rumen’s total bacteria,fungi,Ruminococcus albus and Ruminococcus flavefaciens,while the relative abundance of methanogens was reduced by Lp MTD/1 compared with CON.Principal component analysis of rumen bacterial 16S rRNA gene amplicons showed a clear distinction between CON and inoculated treatments without noticeable distinction between Lp A1 and Lp MTD/1 treatments.Comparison analysis revealed differences in the relative abundance of some bacteria in different taxa between Lp A1 and Lp MTD/1 treatments.Silage treated with Lp A1 exhibited improved rumen fermentation characteristics due to the inoculant effects on the rumen microbial populations and bacterial community.Conclusions Our findings suggest that silage inoculation of the FAE-producing Lp A1 could be effective in improving silage quality and digestibility,and modulating the rumen fermentation to improve feed utilization.展开更多
文摘Ruminants utilize a wide variety of dietary substrates that are not digestible by the mammals, through microbial fermentation taking place in the rumen. Recent advanced molecular based approaches have allowed the characterization of rumen microbiota and its compositional changes under various treatment conditions.However, the knowledge is still limited on the impacts of variations in the rumen microbiota on host biology and function. This review summarizes the information to date on host-microbial interactions in the rumen and how we can apply such information to seek the opportunities to enhance the animal performance through manipulating the rumen function.
基金funded by Nonprofit sector (agriculture) research projects (200903003)
文摘[Objective]This experiment was conducted to investigate the effects of heat stress on microbial numbers in rumen fluid of dairy cows during different lactating periods by real-time PCR.[Methods]A 2 ×3 crossover design was used and eighteen healthy Chinese Holstein cows were selected.The cows were allocated into three periods based on their parity,average days in milk,and milk yield:early lactation(postpartum 15 to 100 days),mid-lactation(postpartum 112 to 175 days)and late lactation(postpartum 200 to 230 days),and six cows in each period.A self-control trial between heat stress period and non-heat stress period was used based on temperature and humidity index(THI)measurement on site.[Results]The results showed as follows:compared with non-heat stress period,heat stress significantly increased the microbial numbers in early lactation,the Ruminococcus flavefaciens number in different lactation and Bacteroides succinogenes number in early and mid-lactation(P 〈0.01).The total bacteria and Ruminococcus albus numbers in mid-and late lactation and Bacteroides succinogenes number in late lactation were decreased significantly by heat stress(P 〈0.01).There were strong correlation between THI and the numbers of total bacteria(P 〈0.01),anaerobic fungi(P 〈0.05),Ruminococcus albus(P 〈0.01)and Ruminococcus flavefaciens(P 〈0.05)in rumen fluid of dairy cows in early lactation,but the correlation between THI and these indexes in mid-and late lactation were poor.[Conclusion]It is indicated that the rumen microbial numbers in early lactation are more sensitive to heat stress.
基金funded by National Natural Science Foundation of China(project no.31901390)China Postdoctoral Science Foundation(project no.2022M711451)Natural Science Foundation of Gansu Province,China(22JR5RA527)。
文摘Background Ferulic acid esterase(FAE)-secreting Lactiplantibacillus plantarum A1(Lp A1)is a promising silage inoculant due to the FAE’s ability to alter the plant cell wall structure during ensiling,an action that is expected to improve forage digestibility.However,little is known regarding the impacts of Lp A1 on rumen microbiota.Our research assessed the influences of Lp A1 in comparison to a widely adopted commercial inoculant Lp MTD/1 on alfalfa’s ensilage,in vitro rumen incubation and microbiota.Results Samples of fresh and ensiled alfalfa treated with(either Lp A1 or Lp MTD/1)or without additives(as control;CON)and ensiled for 30,60 and 90 d were used for fermentation quality,in vitro digestibility and batch culture study.Inoculants treated silage had lower(P<0.001)pH,acetic acid concentration and dry matter(DM)loss,but higher(P=0.001)lactic acid concentration than the CON during ensiling.Compared to the CON and Lp MTD/1,silage treated with Lp A1 had lower(P<0.001)aNDF,ADF,ADL,hemicellulose,and cellulose contents and higher(P<0.001)free ferulic acid concentration.Compared silage treated with Lp MTD/1,silage treated with Lp A1 had significantly(P<0.01)improved ruminal gas production and digestibility,which were equivalent to those of fresh alfalfa.Realtime PCR analysis indicated that Lp A1 inoculation improved the relative abundances of rumen’s total bacteria,fungi,Ruminococcus albus and Ruminococcus flavefaciens,while the relative abundance of methanogens was reduced by Lp MTD/1 compared with CON.Principal component analysis of rumen bacterial 16S rRNA gene amplicons showed a clear distinction between CON and inoculated treatments without noticeable distinction between Lp A1 and Lp MTD/1 treatments.Comparison analysis revealed differences in the relative abundance of some bacteria in different taxa between Lp A1 and Lp MTD/1 treatments.Silage treated with Lp A1 exhibited improved rumen fermentation characteristics due to the inoculant effects on the rumen microbial populations and bacterial community.Conclusions Our findings suggest that silage inoculation of the FAE-producing Lp A1 could be effective in improving silage quality and digestibility,and modulating the rumen fermentation to improve feed utilization.