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
[Objectives]A method for the detection of monensin in poultry and livestock meat by pre-column derivatization-high performance liquid chromatography was established.[Methods]The sample was extracted with chloroform,de...[Objectives]A method for the detection of monensin in poultry and livestock meat by pre-column derivatization-high performance liquid chromatography was established.[Methods]The sample was extracted with chloroform,derivatized with trichloroacetic acid and 2,4-dinitrophenylhydrazine,and centrifuged to obtain a purified solution.A C18 chromatographic column(4.6 mm×150 mm,5μm)was used for separation with(1.5%)acetic acid water∶methanol(volume ratio)=1∶9 as the mobile phase using a DAD detector for detection,and the external standard method was adopted for peak area quantification.[Results]Monensin had good linearity in the concentration range of 5.00-200 mg/L,with the linear correlation coefficient r 2>0.999;the detection limit was 5.00 mg/kg;the relative standard deviation was smaller than 10%;and the recoveries of standard addition experiment were in the range of 75%-110%.[Conclusions]The method has the advantages of simple pretreatment operation,good derivatization effect and fast detection speed,and is suitable for detecting monensin in poultry and livestock meat.展开更多
Studies have shown that supplementing ruminant diets with vegetable oils modulated the rumen biohydrogenation and increased polyunsaturated fatty acid in their products. These positive values are often accompanied by ...Studies have shown that supplementing ruminant diets with vegetable oils modulated the rumen biohydrogenation and increased polyunsaturated fatty acid in their products. These positive values are often accompanied by a marginal loss of supplemented unsaturated fatty acids and rise in the concentrations of saturated fatty acids. This study were carried out mainly to investigate the effect of supplementing diets with sunflower oil, olive oil with or without monensin on the production and accumulation of vaccenic acid(VA) in continuous culture fermenters as a long term in vitro rumen simulation technique.Eight dual-flow continuous culture fermenters were used in an 8 replication experiment lasted 10 days each(first 7 days for adaptation and last 3 days for samples collection). Supplementing diets with plant oils and monensin in the present experiment increased VA and conjugated linoleic acids(P > 0.05) in ruminal cultures. The results suggest that supplementing diets with both olive oil and sunflower oil and monensin increased VA accumulation compared to plant oils supplemented alone without affecting the rumen dry matter and organic matter digestibility.展开更多
Water quality impact due to excessive nutrients has been extensively studied. In recent years, however, micro-pollutants such as pharmaceuticals and hormonal products used in animal agriculture have added an additiona...Water quality impact due to excessive nutrients has been extensively studied. In recent years, however, micro-pollutants such as pharmaceuticals and hormonal products used in animal agriculture have added an additional impact to overall water quality. Pharmaceuticals used in the poultry, swine, beef, and dairy industries have been detected in various environmental matrices such as, soil, groundwater and surface water. In this study, 26 surface water samples were collected throughout the Bosque River Watershed （BRW） with samples representing a range of land use conditions and locations of major dairy operations. Samples were analyzed using commercially available Enzyme-Linked Immunosorbent Assay test. Of the 26 samples, three samples consistently tested positive for monensin antibiotic with concentration ranging from 0.30 to 3.41 μg/L. These three samples were collected from sites that received varying amount of agriculture wastes （11.7% to 31.3%） and located downstream from sites associated with moderate levels of animal agriculture. The preliminary results suggest that there is a potential for monensin occurrence in the BRW, although initial findings indicate only very low levels.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[Objectives]A method for the detection of monensin in poultry and livestock meat by pre-column derivatization-high performance liquid chromatography was established.[Methods]The sample was extracted with chloroform,derivatized with trichloroacetic acid and 2,4-dinitrophenylhydrazine,and centrifuged to obtain a purified solution.A C18 chromatographic column(4.6 mm×150 mm,5μm)was used for separation with(1.5%)acetic acid water∶methanol(volume ratio)=1∶9 as the mobile phase using a DAD detector for detection,and the external standard method was adopted for peak area quantification.[Results]Monensin had good linearity in the concentration range of 5.00-200 mg/L,with the linear correlation coefficient r 2>0.999;the detection limit was 5.00 mg/kg;the relative standard deviation was smaller than 10%;and the recoveries of standard addition experiment were in the range of 75%-110%.[Conclusions]The method has the advantages of simple pretreatment operation,good derivatization effect and fast detection speed,and is suitable for detecting monensin in poultry and livestock meat.
文摘Studies have shown that supplementing ruminant diets with vegetable oils modulated the rumen biohydrogenation and increased polyunsaturated fatty acid in their products. These positive values are often accompanied by a marginal loss of supplemented unsaturated fatty acids and rise in the concentrations of saturated fatty acids. This study were carried out mainly to investigate the effect of supplementing diets with sunflower oil, olive oil with or without monensin on the production and accumulation of vaccenic acid(VA) in continuous culture fermenters as a long term in vitro rumen simulation technique.Eight dual-flow continuous culture fermenters were used in an 8 replication experiment lasted 10 days each(first 7 days for adaptation and last 3 days for samples collection). Supplementing diets with plant oils and monensin in the present experiment increased VA and conjugated linoleic acids(P > 0.05) in ruminal cultures. The results suggest that supplementing diets with both olive oil and sunflower oil and monensin increased VA accumulation compared to plant oils supplemented alone without affecting the rumen dry matter and organic matter digestibility.
文摘Water quality impact due to excessive nutrients has been extensively studied. In recent years, however, micro-pollutants such as pharmaceuticals and hormonal products used in animal agriculture have added an additional impact to overall water quality. Pharmaceuticals used in the poultry, swine, beef, and dairy industries have been detected in various environmental matrices such as, soil, groundwater and surface water. In this study, 26 surface water samples were collected throughout the Bosque River Watershed （BRW） with samples representing a range of land use conditions and locations of major dairy operations. Samples were analyzed using commercially available Enzyme-Linked Immunosorbent Assay test. Of the 26 samples, three samples consistently tested positive for monensin antibiotic with concentration ranging from 0.30 to 3.41 μg/L. These three samples were collected from sites that received varying amount of agriculture wastes （11.7% to 31.3%） and located downstream from sites associated with moderate levels of animal agriculture. The preliminary results suggest that there is a potential for monensin occurrence in the BRW, although initial findings indicate only very low levels.
