Background Stocker cattle diet and management influence beef cattle performance during the finishing stage,but knowledge of the dynamics of the rumen microbiome associated with the host are lacking.A longitudinal stud...Background Stocker cattle diet and management influence beef cattle performance during the finishing stage,but knowledge of the dynamics of the rumen microbiome associated with the host are lacking.A longitudinal study was conducted to determine how the feeding strategy from the stocker to the finishing stages of production affects the temporal dynamics of rumen microbiota.During the stocker phase,either dry hay or wheat pasture were provided,and three levels of monensin were administrated.All calves were then transported to a feedlot and received similar finishing diets with or without monensin.Rumen microbial samples were collected on d 0,28,85 during the stocker stage(S0,S28 and S85)and d 0,14,28,56,30 d before slaughter and the end of the trial during the finishing stage(F0,F14,F28,F56,Pre-Ba,and Final).The V4 region of the bacterial 16S rRNA gene of 263 rumen samples was sequenced.Results Higher alpha diversity,including the number of observed bacterial features and the Shannon index,was observed in the stocker phase compared to the finishing phase.The bacterial amplicon sequence variants(ASVs)differentiating different sampling time points were identified.Dietary treatments during the stocker stage temporally impact the dynamics of rumen microbiota.For example,shared bacteria,including Bacteroidales(ASV19)and Streptococcus infantarius(ASV94),were significantly higher in hay rumen on S28,S85,and F0,while Bacteroidaceae(ASV11)and Limivicinus(ASV15)were more abundant in wheat.Monensin affected rumen microbial composition at a specific time.Transportation to feedlot significantly influenced microbiome structure and diversity in hay-fed calves.Bacterial taxa associated with body weight were classified,and core microbiotas interacted with each other during the trial.Conclusions In summary,the temporal dynamics of the rumen microbiome in cattle at the stocker and finishing stage are influenced by multiple factors of the feeding strategy.Diet at the stocker phase may temporarily affect the microbial composition during this stage.Modulating the rumen microbiome in the steers at the stocker stage affects the microbial interactions and performance in the finishing stage.展开更多
This study, with the shake table experiments in the National Earthquake Engineering Research Center, investigated the seismic behavior of automation stocker system. The automation stocker system provided a fast and ef...This study, with the shake table experiments in the National Earthquake Engineering Research Center, investigated the seismic behavior of automation stocker system. The automation stocker system provided a fast and effective method for stocking products in the high-tech facilities. Firstly, the original machine tests for testing common stocker system were to investigate the seismic capacity and failing modes. Secondly, the team completed 2 kinds of reinforcement tests to investigate the seismic behavior: 1) the installation of bracing to improve overall stiffness;2) the installation of the viscous dampers to improve the overall damping ratio. In comparing the results and performance of the three experiments, we learned from the results of the top-layer acceleration: the installation of bracing had the largest acceleration value, the original machine the second acceleration value and the damper the lowest acceleration value;the best effect was the installation of the damper. The result of the comparison of the top floor displacement meter showed that the highest data was the original machine;the second data was with the damper, the lowest data was the installation of the bracing. Based on the preliminary assessment on the best seismic retrofit ways of the storage system, we further examined the feasibility and applicability of automatic storage seismic retrofit in the high-tech factory.展开更多
基金the University of Arkansas Agricultural Experiment Station,Hatch Project No.AR002234,National Natural Science Foundation of China(32170430)Guangdong Provincial Key Laboratory of Animal Molecular Design and Precise Breeding(2019B030301010)Key Laboratory of Animal Molecular Design and Precise Breeding of Guangdong Higher Education Institutes(2019KSYS011).
文摘Background Stocker cattle diet and management influence beef cattle performance during the finishing stage,but knowledge of the dynamics of the rumen microbiome associated with the host are lacking.A longitudinal study was conducted to determine how the feeding strategy from the stocker to the finishing stages of production affects the temporal dynamics of rumen microbiota.During the stocker phase,either dry hay or wheat pasture were provided,and three levels of monensin were administrated.All calves were then transported to a feedlot and received similar finishing diets with or without monensin.Rumen microbial samples were collected on d 0,28,85 during the stocker stage(S0,S28 and S85)and d 0,14,28,56,30 d before slaughter and the end of the trial during the finishing stage(F0,F14,F28,F56,Pre-Ba,and Final).The V4 region of the bacterial 16S rRNA gene of 263 rumen samples was sequenced.Results Higher alpha diversity,including the number of observed bacterial features and the Shannon index,was observed in the stocker phase compared to the finishing phase.The bacterial amplicon sequence variants(ASVs)differentiating different sampling time points were identified.Dietary treatments during the stocker stage temporally impact the dynamics of rumen microbiota.For example,shared bacteria,including Bacteroidales(ASV19)and Streptococcus infantarius(ASV94),were significantly higher in hay rumen on S28,S85,and F0,while Bacteroidaceae(ASV11)and Limivicinus(ASV15)were more abundant in wheat.Monensin affected rumen microbial composition at a specific time.Transportation to feedlot significantly influenced microbiome structure and diversity in hay-fed calves.Bacterial taxa associated with body weight were classified,and core microbiotas interacted with each other during the trial.Conclusions In summary,the temporal dynamics of the rumen microbiome in cattle at the stocker and finishing stage are influenced by multiple factors of the feeding strategy.Diet at the stocker phase may temporarily affect the microbial composition during this stage.Modulating the rumen microbiome in the steers at the stocker stage affects the microbial interactions and performance in the finishing stage.
文摘This study, with the shake table experiments in the National Earthquake Engineering Research Center, investigated the seismic behavior of automation stocker system. The automation stocker system provided a fast and effective method for stocking products in the high-tech facilities. Firstly, the original machine tests for testing common stocker system were to investigate the seismic capacity and failing modes. Secondly, the team completed 2 kinds of reinforcement tests to investigate the seismic behavior: 1) the installation of bracing to improve overall stiffness;2) the installation of the viscous dampers to improve the overall damping ratio. In comparing the results and performance of the three experiments, we learned from the results of the top-layer acceleration: the installation of bracing had the largest acceleration value, the original machine the second acceleration value and the damper the lowest acceleration value;the best effect was the installation of the damper. The result of the comparison of the top floor displacement meter showed that the highest data was the original machine;the second data was with the damper, the lowest data was the installation of the bracing. Based on the preliminary assessment on the best seismic retrofit ways of the storage system, we further examined the feasibility and applicability of automatic storage seismic retrofit in the high-tech factory.
