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:Longissimus muscle samples were collected from lambs exposed in utero to mycotoxins (E-, endophyte-free tall fescue seed without ergot alkaloids or E+, endophyte-infected tall fescue seed containing ergot alkaloids) during mid-gestation (MID; E+/E-; N) or late-gestation (LATE; E-/E+; T) harvested at two developmental stages (FETAL, gestational d133) or (MKT, near maturity, 250 d of age). Muscle samples were examined to determine the impact of in utero mycotoxin exposure on skeletal muscle fiber hypertrophy and the miRNA transcriptome at FETAL and MKT.
Project description:Pregnant Suffolk ewes (n = 19; 81.2kg ± 7.7) estimated to be carrying twins were assigned to endophyte-infected tall fescue seed (E+; 4.14 µg ergovaline + ergovalinine/g seed) or a control diet (CON; 0 µg ergovaline + ergovalinine) and evaluated at different stages of gestation (gd85 [pre-treatment, n = 3], gd110 [n = 4/treatment] or gd133 [n = 4/treatment). Ewes were individually fed a basal diet with (E+) or without (CON) endophyte-infected tall fescue seed from gd86 to gd110 or gd133. A terminal necropsy was performed, and uterine components were evaluated for size, weight, and type. Data were analyzed using a priori contrasts to test effects of stage of gestation (gd85 vs. gd110 or gd110 vs. gd133) and adaptive responses to feeding E+ fescue seed versus CON at gd110 and gd133. Serum prolactin concentrations were greater (P < 0.05) at gd110 than gd85, and then remained constant to gd133. Feeding E+ tall fescue seed reduced (P < 0.05) serum prolactin concentrations compared to CON at both gd110 and gd133. From gd85 to gd110, placentome type and number changed from type A to type B (P < 0.05) but did not change (P > 0.05) after gd110. Total fetal weight per ewe increased 2977 g from gd85 to gd110 (P = 0.011) and then 3151 g from gd110 to 133 (P = 0.012). Brain weight as a percentage of fetal body weight was higher (P = 0.029) for E+ fetuses on gd110 compared to CON, which demonstrates asymmetrical growth and intrauterine growth restriction (IUGR). In total, 15,961 genes were identified in the cotyledon through mapping to the ovine genome across all samples. There were 136 genes differentially expressed (FDR < 0.05; log2foldchange < -1 and > 1) from gd85 to gd110 with ovarian steroidogenesis and steroid biosynthesis pathways enriched and 469 genes differentially expressed from gd110 to gd133 with ribosome and oxidative phosphorylation pathways enriched. Exposure to E+ fescue resulted in differential expression of 22 genes at gd110 but only one gene at gd133 compared to CON. These results show that there are major changes in fetal growth and placental remodeling during the late gestation period that are influenced by exposure to ergot alkaloids from endophyte-infected tall fescue seed; however, major changes in the transcriptome of the cotyledon tissue in response to E+ fescue were not observed and other factors must be involved in the reduction of placental efficiency and fetal growth observed with E+ fescue exposure.
Project description:The objective of our study was to assess the effect of fescue toxicosis on the overall transcriptomics profile of liver tissue on growing Angus × Simmental steers and heifers. The susceptibility was determined by the T-snip genetic tests for a total of 42 pregnant cows. At mid-gestation, these animals were randomly assigned to control group which received a based diet and fed endophyte free fescue seeds; a treatment group was fed endophyte-infected tall fescue seeds for 30 days. RNA-seq experiments were performed in liver biopsy samples, and a total of 828 differentially expressed genes were detected.
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:Consumption of ergot alkaloids, specifically ergovaline, found in endophyte-infected tall fescue causes potent vasoconstriction and has been linked to reductions in placental mass and fetal growth and development. The objective of this study was to elucidate differences in the cotyledonary transcriptome of ewes consuming ergovaline during gestation through RNA-sequencing.