Project description:This study examined tolerance to hypoxia-induced pulmonary hypertension in yearling beef cattle raised at high elevation (7120 ft/2170m).
Project description:Bovine Viral Diarrhea Virus (BVDV) is an endemic virus of North American cattle populations with significant economic and animal health impacts. While BVDV infection has a myriad of clinical manifestations, a unique and problematic outcome is the establishment of a persistently infected (PI) animal following in-utero viral infection. While it is well established that PI animals serve as a constant reservoir of BVDV, the mechanism for the maintained infection remains unknown despite multiple theories. The purpose of this study was to use transcriptome analysis to further define long term immune status of adult PI cattle and offer insight into the potential mechanistic establishment of persistent BVDV infection, in utero. Peripheral blood mononuclear cells were collected from PI beef cattle (N=6) and uninfected controls (N=6) for targeted RNAseq analysis conducted using 54 genes of interest and followed by pathway enrichment analysis. Analysis revealed 29 differentially expressed genes (FDR < 0.05, fold change > 2) representing 14 significant KEGG pathways between PI and control animals (FDR < 0.05). Transcriptome changes indicate chronic upregulation of interferon gamma (IFNG) with unexpected expression of related genes, suggesting a maintained stimulation of the PI immune system resulting in virus-mediated dysregulation of immune function.
Project description:Creatine pyruvate (CrPyr) is a new multifunctional nutrient that can provide both pyruvate and creatine. It has been shown to relieve the heat stress of beef cattle by improving antioxidant activity and rumen microbial protein synthesis, but the mechanism of CrPyr influencing rumen fermentation remains unclear. This study aimed to use metaproteomics technologies to investigate the bacterial protein function in rumen fluid samples taken from heat-stressed beef cattle treated with or without 60 g/d CrPyr.
Project description:In the present study, a oligonucleotide microarray platform is used to compare expression profiles of beef cattle muscle in animals treated with either Dexamethazone (Dex) or Dexamethazone plus 17?-estradiol (Estr) administered at sub-therapeutic dosage, against untreated controls. Seventeen male beef cattle 15-18 months old, around 450 kg mean body weight were randomly allocated in three groups: 6 were untreated (group Ctrl), 5 were administered with dexamethazone via feed 0.75mg/head for 43 days (group D); the last 6 animals were administered via feed for 43 days with Dex (0.75mg/head) and intramuscularly (i.m.) for three times with 17?-oestradiol, 20mg/head, (group DE). Three additional control animals, matching in sex and age, collected in a previous experiment were included in the Ctrl group to increase sample size and to control for biological variation. For each sample, total RNA was extracted from a specific anterior limb muscle (biceps branchii). Data analysis demonstrates that the expression profiles were strongly affected by Dex treatment with hundreds of genes up-regulated with relevant fold-change, whereas the myostatin gene was significantly down-regulated. On the contrary, the administration of Dex-Estr reveals a weaker effect on gene expression. In this study, we analyzed the gene expression profiles of 20 anterior limb muscle samples, 9 collected from untreated controls, 5 collected from cattle treated with Dex and 6 from cattle treated with Dex+Estr using Agilent-015354 Bovine oligo microarray platform (20 arrays, no replicate) based on single-colour detection (Cyanine-3 only). Microarrays are scanned with Agilent scanner G2565BA (barcode on the left, DNA on the back surface, scanned through the glass) at a resolution of 5 microns; all slides are scanned twice at two different sensitivity settings (XDRHi 100% and XDRLo 10%); the scanner software creates a unique ID for each pair of XDR scans and saves it to both scan image files. Feature Extraction 9.5 uses XDR ID to link the pairs of scans together automatically when extracting data. The signal left after all the FE processing steps have been completed is ProcessedSignal that contains the Multiplicatively Detrended, Background-Subtracted Signal
Project description:RNA-seq from backfat tissues were obatained from 22 steers, including Angus (AN; n=8), Charolais (CH; n=6), and Kinsella composite (KC; n=8). In each breed, cattle were classified two groups, i.e. high residual feed intake adjusted for off-test backfat thickness (RFIfat, RFIfat >= 0.5) and low RFIfat (RFIfat <= -0.5). For gene analysis, 46, 39 and 177 differentially expressed (DE) genes were identified in AN, CH and KC, respectively. Among them, 4, 17, 74 genes were up-regulated in high RFIfat as compared to low RFIfat in AN, CH and KC, respectively. All DE genes were used for functional and upstream analysis in Ingenuity Pathway Analysis. Some DE genes were involved in reduction of carbohydrate metabolism in AN, and reduction of lipid metabolism in KC.