Project description:Growing and finishing phases are two important animal production stages, which differ fundamentally in compositional growth. However, the physiological mechanisms altered concomitantly with the shift in whole-body compositional gain as cattle fatten (growing vs. finished steers), are poorly understood. Microarray analysis using the Bovine Gene 1.0 ST Array was conducted to determine shifts in hepatic genomic expression profiles of growing vs. finishing beef steers. The specific overall hypothesis tested was that genes involved in amino acid, carbohydrate and lipid metabolism, antioxidant capacity and immune responses were differentially expressed in growing vs. finishing steers.
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: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: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: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.
Project description:Steer liver transcriptome Evaluation of the naturally occurring transcriptome variation in liver among beef steers with divergent gain and feed intake phenotypes.
Project description:Beef represents a major diet component and source of protein in many countries. With an increment demand for beef, the industry is currently undergoing changes towards natural produced beef. Consumers not only concern about product quality, but also for the well-being of animals. Therefore, the consumption of grass-fed meat is continuously growing. However, the nutritional true differences between feeding systems are still unclear. The aim of this study was to examine latissimus dorsi muscle quality and animal welfare by transcriptome and metabolome profiles, and to identify biological pathways related to the differences between grass- and grain-fed Angus steers. By RNA-Seq analysis of latissimus dorsi muscle, we have recognized 241 differentially expressed genes (FDR < 0.1). The metabolome examination of muscle and blood revealed 163 and 179 altered compounds in each tissue (P-value < 0.05), respectively. Accordingly, alterations in glucose metabolism, divergences in free fatty acids and carnitine conjugated lipid levels, and altered β-oxidation, have been observed. In summary, this study demonstrates a unique transcriptomic and metabolic signature in the muscle of grain and grass finished cattle. Results support the accumulation of anti-inflammatory n3 polyunsaturated fatty acids in grass finished cattle, while higher levels of n6 PUFAs in grain finished animals may promote inflammation and oxidative stress. Furthermore, grass-fed animals produce tender beef with lower total fat and higher omega3/omega6 ratio than grain fed animals, which could potentially benefit consumer health. Finally, blood cortisol levels strongly indicate that grass fed animals experience less stress than the grass fed individuals The steers came from a closed Wye Angus herd with very similar genetics. The grass-fed group was comprised of steers that received alfalfa and orchard grass hay, clover and orchard grass pasture, or orchard grass and alfalfa pasture. The grass-fed individuals consumed grazed alfalfa upon availability and bales during winter and were not exposed to any corn, any form of grain or feed by-products. The alfalfa and grass hay were harvested from land that has had minimal fertilizer and no application of pesticides or inorganic chemicals. The control group was fed a conventional diet consisting of corn silage, soybean, shelled corn and minerals. The pastures were managed as organic landsâwithout fertilizers, pesticides or any chemical additives. At the slaughter plant, 10 ml whole blood sample from the jugular vein was collected in EDTA tubes and directly storage at -80°C. Then, a small piece of longissimus dorsi muscle was obtained from each hot carcass at the level of the 12th intercostal space and immediately frozen in dry ice for posterior analysis.
Project description:Steer spleen transcriptome Evaluation of the naturally occurring transcriptome variation in the spleen among beef steers with divergent gain and feed intake phenotypes.
Project description:Beef represents a major diet component and source of protein in many countries. With an increment demand for beef, the industry is currently undergoing changes towards natural produced beef. Consumers not only concern about product quality, but also for the well-being of animals. Therefore, the consumption of grass-fed meat is continuously growing. However, the nutritional true differences between feeding systems are still unclear. The aim of this study was to examine latissimus dorsi muscle quality and animal welfare by transcriptome and metabolome profiles, and to identify biological pathways related to the differences between grass- and grain-fed Angus steers. By RNA-Seq analysis of latissimus dorsi muscle, we have recognized 241 differentially expressed genes (FDR < 0.1). The metabolome examination of muscle and blood revealed 163 and 179 altered compounds in each tissue (P-value < 0.05), respectively. Accordingly, alterations in glucose metabolism, divergences in free fatty acids and carnitine conjugated lipid levels, and altered β-oxidation, have been observed. In summary, this study demonstrates a unique transcriptomic and metabolic signature in the muscle of grain and grass finished cattle. Results support the accumulation of anti-inflammatory n3 polyunsaturated fatty acids in grass finished cattle, while higher levels of n6 PUFAs in grain finished animals may promote inflammation and oxidative stress. Furthermore, grass-fed animals produce tender beef with lower total fat and higher omega3/omega6 ratio than grain fed animals, which could potentially benefit consumer health. Finally, blood cortisol levels strongly indicate that grass fed animals experience less stress than the grass fed individuals
Project description:Steer mesenteric fat transcriptome. Evaluation of the naturally occurring transcriptome variation in mesenteric fat among beef steers with divergent gain and feed intake phenotypes.