Project description:We explored the effect of long-term high-concentrate diet feeding on ruminal pH and fermentation, and its effect on the rumen epithelial transcriptomes in Japanese Black beef cattle during a 20-month fattening period.
Project description:Vitamin A (VA) restriction for beef cattle improves meat marbling. However, its molecular mechanisms are not completely elucidated. We performed microarray analysis to clarify effect of VA restriction on longissimus thoracis muscle gene expressions in Japanese Black steers.
Project description:Microarray gene expression profiling to identify differentially regulated genes in Musculus longissimus dorsi (MLD) of Japanese Black (JB) steers compared to Holstein steers (HS)
Project description:Three Japanese Black (JB) and 3 Holstein (HS) steers were fed a high energy diet and were slaughtered with 26 months of age. Intramuscular (IMF) and subcutaneous fat (SCF) was sampled to reveal differences in the expression profiles between the breeds and adipose depots.
Project description:Three Japanese Black (JB) and 3 Holstein (HS) steers were fed a high energy diet and were slaughtered with 26 months of age. Intramuscular (IMF) and subcutaneous fat (SCF) was sampled to reveal differences in the expression profiles between the breeds and adipose depots. Pair wise comparison of JB and HS within IMF and SCF; pairwise comparision of IMF and SCF over both breeds.
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:We profiled blood transcriptomics of 24 beef steers at three important stages (Entry: on arrival at the feedlot; Pulled: when sickness is identified; and Close-out: recovered, healthy cattle at shipping to slaughter) to reveal the key biological functions and regulatory factors of BRD and identify gene markers of BRD for early diagnosis and potentially use in selection.
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 biological mechanisms associated with the residual feed intake in ruminants have been harnessed immensely via transcriptome analysis of liver and ruminal epithelium, however, this concept has not been fully explored using whole blood. We applied whole blood transcriptome analysis and gene set enrichment analysis to identify key pathways associated with divergent selection for low or high RFI in beef cattle. A group of 56 crossbred beef steers (average BW = 261.3 ± 18.5 kg) were adapted to a high-forage total mixed ration in a confinement dry lot equipped with GrowSafe intake nodes for period of 49 d to determine their residual feed intake (RFI). After RFI determination, weekly whole blood samples were collected three times from beef steers with the lowest RFI (most efficient; low-RFI; n = 8) and highest RFI (least efficient; high-RFI; n = 8). Prior to RNA extraction, whole blood samples collected were composited for each steer. Sequencing was performed on an Illumina NextSeq2000 equipped with a P3 flow. Gene set enrichment analysis (GSEA) was used to analyze differentially expressed gene sets and pathways between the two groups of steers. Results of GSEA revealed pathways associated with metabolism of proteins, cellular responses to external stimuli, stress, and heat stress were differentially inhibited (false discovery rate (FDR) < 0.05) in high-RFI compared to low-RFI beef cattle, while pathways associated with binding and uptake of ligands by scavenger receptors, scavenging of heme from plasma, and erythrocytes release/take up oxygen were differentially enriched (FDR < 0.05) in high-RFI, relative to low-RFI beef cattle. Taken together, our results revealed that beef steers divergently selected for low or high RFI revealed differential expressions of genes related to protein metabolism and stress responsiveness.
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.
