Project description:Neotyphodium coenophialum is an endophytic fungus that infects most tall fescue (Festuca arundinacea) pastures that are commonly used in animal grazing systems in the United States. Beef cattle grazing such pastures are impaired in health and production performance, resulting in a large economic loss in US food-animal production systems. Based on clinical and biochemical blood analyte profiles, hepatic targeted gene and protein analyses, and hepatic transcriptomic profiling, microarray analysis using the WT Btau 4.0 Array (version 1.0, Affymetrix, Inc., Santa Clara, CA) was conducted to determine if grazing endophyte-infected tall fescue pastures affects pituitary gene expression profiles of growing beef steers. The specific overall hypothesis tested was that grazing high endophyte-infected pasture would alter the pituitary genomic expression profiles of the same growing steers, especially genes involved in production and secretion of prolactin, growth hormone, thyroid stimulating hormone, and adrenocorticotropic hormone. Sixteen steers were assigned to graze either a low toxic endophyte tall fescue-mixed grass (LE treatment, 5.7 ha, n = 8) or a high toxic endophyte infected tall fescue (HE treatment, 5.7 ha, n = 8) pasture located in the University of Kentucky Agricultural Research Center. All steers had ad libitum access to fresh water, an industry standard mineral-vitamin supplement, and grazed respective pastures for 89 to 105 days. Whole pituitaries were collected for RNA extraction and microarray analysis.
Project description:The effects of anti-lipopolysaccharide (LPS) antibody on ruminal fermentation, LPS activity, and liver transcriptomes were investigated during the subacute ruminal acidosis (SARA) challenge.
Project description:Neotyphodium coenophialum is an endophytic fungus that infects most tall fescue (Festuca arundinacea) pastures that are commonly used in animal grazing systems in the United States. Beef cattle grazing such pastures are impaired in health and production performance, resulting in a large economic loss in US food-animal production systems. Based on the clinical symptoms and laboratory analyses of blood, it was hypothesized that such affected cattle display liver-specific changes in the expression of gene transcripts that are associated with the metabolic enzymes and transporters critical for beef health and performance. Microarray analysis using the GeneChip Bovine Genome Array (Affymetrix, Inc., Santa Clara, CA) was conducted to determine if grazing endophyte-infected tall fescue pastures affects the liver gene expression profiles of growing beef steers. Nineteen steers were assigned to graze either a low toxic endophyte tall fescue-mixed grass (LE treatment, 5.7 ha, n = 9) or a high toxic endophyte infected tall fescue (HE treatment, 5.7 ha, n = 10) pasture located in the University of Kentucky Agricultural Research Center. All steers had ad libitum access to fresh water and an industry standard mineral-vitamin supplement. 88 days grazing on pasture. Approximately 2 g of tissue from the right lobe of the liver of each steer were collected for RNA extraction and microarray analysis.
Project description:The goal of this study was to test the hypothesis that sodium selenite (ISe), SEL-PLEX (OSe), vs. a 1:1 blend (MIX) of ISe and OSe in a basal vitamin-mineral (VM) mix would differetianlly alter hepatic transcriptome profiles in growing beef steers commonly grazing an endophyte-infected tall fescue (E+) pasture. Predominately-Angus steers (BW = 183 ± 34 kg) were randomly selected from herds of fall-calving cows grazing E+ pasture and consuming VM mixes that contained 35 ppm Se as ISe, OSe, and MIX forms. Steers were weaned, depleted of Se for 98 d, and subjected to summer-long common grazing of an E+ pasture (0.51 ppm total ergovaline per ergovalinine; 10.1 ha). Steers were assigned (n = 8 per treatment) to the same Se-form treatments upon which they were raised. Selenium treatments were administered by daily top-dressing 85 g of VM mix onto 0.23 kg soyhulls, using in-pasture Calan gates. We collected liver samples and examined for changes in global expression pattern by microarray analysis.
Project description:The goal of this study was to test the hypothesis that sodium selenite (ISe), SEL-PLEX (OSe), vs. a 1:1 blend (MIX) of ISe and OSe in a basal vitamin-mineral (VM) mix would differetianlly alter pituitary transcriptome profiles in growing beef steers commonly grazing an endophyte-infected tall fescue pasture. Predominately-Angus steers (BW = 183 ± 34 kg) were randomly selected from herds of fall-calving cows grazing E+ pasture and consuming VM mixes that contained 35 ppm Se as ISe, OSe, and MIX forms. Steers were weaned, depleted of Se for 98 d, and subjected to summer-long common grazing of an E+ pasture (0.51 ppm total ergovaline per ergovalinine; 10.1 ha). Steers were assigned (n = 8 per treatment) to the same Se-form treatments upon which they were raised. Selenium treatments were administered by daily top-dressing 85 g of VM mix onto 0.23 kg soyhulls, using in-pasture Calan gates. We collected pituitary samples and examine for changes in global expression pattern by microarray analysis.
Project description:Neotyphodium coenophialum is an endophytic fungus that infects most tall fescue (Festuca arundinacea) pastures that are commonly used in animal grazing systems in the United States. Beef cattle grazing such pastures are impaired in health and production performance, resulting in a large economic loss in US food-animal production systems. Based on clinical and biochemical blood analyte profiles, hepatic targeted gene and protein analyses, and hepatic transcriptomic profiling, microarray analysis using the BovGene-1_0-v1 array (Affymetrix) was conducted to determine if grazing endophyte-infected tall fescue pastures affects pituitary gene expression profiles of growing beef steers. The specific overall hypothesis tested was that grazing high endophyte-infected pasture would alter the pituitary genomic expression profiles of the same growing steers, especially genes involved in production and secretion of prolactin, growth hormone, thyroid stimulating hormone, and adrenocorticotropic hormone.
Project description:Beef represents a major diet component and one of the major sources of protein in human. The beef industry in the United States is currently undergoing changes and is facing increased demands especially for natural grass-fed beef. The grass-fed beef obtained their nutrients directly from pastures, which contained limited assimilable energy but abundant amount of fiber. On the contrary, the grain-fed steers received a grain-based regime that served as an efficient source of high-digestible energy. Lately, ruminant animals have been accused to be a substantial contributor for the green house effect. Therefore, the concerns from environmentalism, animal welfare and public health have driven consumers to choose grass-fed beef. Rumen is one of the key workshops to digest forage constituting a critical step to supply enough nutrients for animals’ growth and production. We hypothesize that rumen may function differently in grass- and grain-fed regimes. The objective of this study was to find the differentially expressed genes in the ruminal wall of grass-fed and grain-fed steers, and then explore the potential biopathways. In this study, the RNA Sequencing (RNA-Seq) method was used to measure the gene expression level in the ruminal wall. The total number of reads per sample ranged from 24,697,373 to 36,714,704. The analysis detected 342 differentially expressed genes between ruminal wall samples of animals raised under different regimens. The Fisher’s exact test performed in the Ingenuity Pathway Analysis (IPA) software found 16 significant molecular networks. Additionally, 13 significantly enriched pathways were identified, most of which were related to cell development and biosynthesis. Our analysis demonstrated that most of the pathways enriched with the differentially expressed genes were related to cell development and biosynthesis. Our results provided valuable insights into the molecular mechanisms resulting in the phenotype difference between grass-fed and grain-fed cattle. Ruminal wall samples from two randomly chosen animals per group were obtained, totaling four samples. The animals were born, raised and maintained at the Wye Angus farm. This herd, which has been closed for almost 75 years and yielded genetically similar progenies, constitutes an excellent resource to perform transcriptomic analysis. The genetic resemblance among individuals permits us to better control the cause of variation between experimental clusters and individuals. The randomly chosen pairs of animals were part of larger sets of steers that received a particular treatment. All animals received the same diet until weaning. The grain group received conventional diet consisting of corn silage, shelled corn, soy bean and trace minerals. The grass fed steers consumed normally grazed alfalfa; during wintertime, bailage was utilized. The alfalfa has been harvested from land without any fertilizers, pesticides or other chemicals. The steers ate no animal, agricultural or industrial byproducts and never receive any type of grain. Then, the calves were randomly assigned to one diet and exclusively received that regimen until termination. Grain–fed animals reached the market weight around the age of 14 month-old, however, grass-fed steers required approximately 200 additional days to achieve the same weight. Immediately after termination at the Old Line Custom Meat Company (Baltimore, MD) a small piece of ruminal wall was excised, cleaned and preserved at -80°C for posterior processing.
Project description:We investigated the effects of wood kraft pulp (WP) supplementation on ruminal pH, fermentation, and epithelial transcriptomic dynamics in Holstein cattle during the high-grain diet challenge.
Project description:We investigated changes in rumen fermentation, peripheral blood metabolites and hormones, and hepatic transcriptomic dynamics in Holstein cows with and those without subacute ruminal acidosis (SARA) during the periparturient period.
Project description:Neotyphodium coenophialum is an endophytic fungus that infects most tall fescue (Festuca arundinacea) pastures that are commonly used in animal grazing systems in the United States. Beef cattle grazing such pastures are impaired in health and production performance, resulting in a large economic loss in US food-animal production systems. Based on the clinical symptoms and laboratory analyses of blood, it was hypothesized that such affected cattle display liver-specific changes in the expression of gene transcripts that are associated with the metabolic enzymes and transporters critical for beef health and performance. Microarray analysis using the GeneChip Bovine Genome Array (Affymetrix, Inc., Santa Clara, CA) was conducted to determine if grazing endophyte-infected tall fescue pastures affects the liver gene expression profiles of growing beef steers.