Project description:The objective was to study the transcriptomic changes in adipose tissue in the early stages of lactation, specifically in Bos Taurus, Holstein dairy cattle as a function of milk production and genetic merit. Chip quality backgrounds averaged below 50 units, and 3'/5' bias on control genes < 2.0. Correlations among replicates were > 0.85. The design was a simple paired sampling, with time (30 d prepartum and 14 d postpartum as the sampling times. There was no dietary manipulation. Animals were all first calving Holstein heifers, all raised on the same farm on the same diet
Project description:12 Holstein dairy heifers were limit-fed with high or low forage diets, and integrative hepatic metabolomics and proteomics were used to reveal insights into the mechanism of different feed efficiency behind that.
Project description:The potential for dietary supplementation with n-3 polyunsaturated fatty acids (n-3 PUFA) to improve reproductive efficiency in cattle has received much interest. The mechanisms by which n-3 PUFA may affect physiological and biochemical processes in key reproductive tissues are likely to be mediated by significant alterations in gene expression. We used microarrays to assess endometrial gene expression on day 17 of the estrous cycle in n-3 PUFA compared with control fed heifers. Beef heifers were supplemented with a rumen protected source of either a saturated fatty acid (CON; palmitic acid) or high n-3 PUFA (n-3 PUFA; 275 g) diet per animal per day for 45 days and global gene expression was determined in uterine endometrial tissue using an Affymetrix® oligonucleotide bovine array.
Project description:We carried out an experiment to test the hypothesis that differences in protein abundance due to fertility fitness would be shared between heifers of different breeds. We produced proteome data from the plasma collected from 22 heifers (purebred Angus heifers (n=12), purebred Holstein (n=10) heifers). The protein Alpha-ketoglutarate-dependent dioxygenase FTO was more abundant in the plasma collected from Fertile heifers relative to Sub-fertile counterparts (FDR < 0.05).
Project description:The SLICK1 mutation confers thermotolerance to cattle inheriting one or two copies of the gene. Results are unclear as to whether the mutation changes capacity of animals to undergo sweating during heat stress. Accordingly, differences in characteristics of sweat glands between slick and wildtype Holstein heifers was determined. There were no differences in the proportion of skin occupied by sweat glands but sweat glands from slick heifers had higher amounts of immunoreactive FOXA1 than wildtype heifers. FOXA1 is a transcription factor important for sweating. While results do not support the idea that the SLICK1 mutation changes the abundance of sweat glands in skin, it did affect functional properties of sweat glands, as indicated by increased abundance of immunoreactive FOXA1.
Project description:The aim of this study was to examine the effect of sire fertility status on conceptus-induced changes in the endometrial transcriptome. Holstein Friesian bulls (3 High fertility, HF, 3 Low fertility, LF) were selected from the Irish national population of AI bulls (minimum of 500 inseminations/bull) based on adjusted fertility scores (HF: +4.37% and LF: -12.7%; mean = 0%). To generate elongated conceptuses, Day 7 blastocysts produced in vitro using sperm from these six bulls were transferred in groups of 5-10 to synchronized heifers (n=7 heifers per bull; total 42 heifers). Conceptuses were recovered following slaughter on Day 15 (recovery rate: HF 59.4% vs. LF 45.0%; P<0.05). In parallel, Day 15 endometrial explants were recovered from synchronized cyclic heifers (n=4). Explants from each heifer were co-cultured for 6 h in RPMI medium with (i) nothing, control (ii) 100 ng/ml ovine recombinant interferon tau (IFNT) (iii) a single conceptus from each high fertility bull, or (iv) a single conceptus from each low fertility bull. To minimize variation, explants from the same uterus were used across all treatments, replicated across 4 heifers. After 6 h, explants were snap frozen and stored at -80°C. Extracted mRNA was subjected to RNA-seq (Illumina NextSeq 500) and the resulting data were analyzed through a bioinformatic pipeline with R software.
