Project description:The aim of this study was to measure the impact of contrasting feeding regimes in the first 12 wk of life, known to impact age at puberty on the molecular control of the testes in bull calves. Holstein bull calves were designated to high (HI; n=15) or moderate (MOD; n=15) dietary groups, with diets designed to provoke growth rates of 1.0 and 0.5 kg/day, respectively. At 12 wk of age, all calves were euthanized, and testes parenchyma harvested. RNA was extracted from the testes and used for miRNAseq. Bioinformatic analysis identified 7 miRNA as differentially expressed between the HI and MOD treatment groups, with target mRNA genes invovled in pathways related to AMPK and IGF-1 signaling.
Project description:This study evaluated the effect of enhanced dietary intake during the early life period on testes transcriptome in bull calves. Between 2-12 weeks of age bull alves were offered either a high (HI; n=15) or moderate (MOD; n=15) plane of nutrition, with diets designed to evoke growth rates of 1.0 and 0.5 kg/day, respectively. At 12 wk of age, testes parenchyma tissue samples were harvested from all calves and subsequently subjected to mRNAseq. Subsequent bioinformatics analyses revealed differential expression of genes invovled in cellular adhesion and immune function.
Project description:Using Illumina® BovineHD Genotyping BeadChip assay, we applied single sperms genotyping from one single Holstein bull to preliminarily describe its recombination map. We received 56 single sperms with qualified genotype information and totally detected 1,526 autosomal crossovers.
Project description:Predicting dairy bull fertility is a current challenge for the dairy industry. The goal of this study was to integrate DNA methylation data with previously published RNA sequencing results in order to identify candidate markers for sire fertility.
Project description:Prediction of male or semen fertility potential remains a persistent challenge that has yet to be fully resolved. This work analyzed several in vitro parameters and proteome of spermatozoa in bulls cataloged as high (HF; n=5) and low field (LF; n=5) fertility after more than a thousand artificial inseminations. Sperm motility was evaluated by Computer-Assisted Sperm Analysis. Sperm viability, mitochondrial membrane potential (MMP), and reactive oxygen species (mROS) of spermatozoa were assessed by flow cytometry. Proteome was evaluated by SWATH-MS procedure. Spermatozoa of HF bulls showed significantly higher total motility than the LF group (41.4% vs. 29.7%). Rates of healthy sperm (live, high MMP, and low mROS) for HF and LF bull groups were 49% and 43%, respectively (p > 0.05). Spermatozoa of HF bulls showed higher presence of differentially abundant proteins (DAPs) related to both energy production (COX7C), mainly OXPHOS pathway, and to the development of structures linked with the motility process (TPPP2, SSMEM1 and SPAG16). Furthermore, we observed that EQTN, together with other DAPs related to the interaction with the oocyte, were overrepresented in HF bull spermatozoa. The biological processes related to protein processing, catabolism, and protein folding were found to be overrepresented in LF bull sperm in which the HSP90AA1 chaperone was identified as the most DAP
Project description:It has been established that enhanced early life nutrition progresses sexual development in the bull calf through neuroendocrine signalling via the hypothalamic-pituitary-testicular axis. However, the underlying molecular mechanisms regulating this process have not been fully elucidated. This study measured the impact of contrasting feeding regimes in the first 12 wk of life, known to impact age at puberty, on the proteomic landscape of the testes of bull calves. Holstein bull calves with a mean (±SD) bodyweight and age of 48.8 (± 5.3) kg and 17.5 (± 2.8) days, were designated to high (HI; n=10) or moderate (MOD; n=10) dietary groups, with diets designed to provoke growth rates of 1.0 and 0.5 kg/day, respectively. At 12 wk of age, all calves were euthanized, and testes parenchyma harvested. HI calves were heavier at slaughter (112.4 v 88.7 (2.98) kg, P<0.001), and had a greater average daily gain (ADG) of (0.88 v 0.58 kg, P<0.001). The turquoise network from the protein analyses contained the protein CDH13 which is involved in testes development. Gene ontology analysis of the turquoise network revealed enrichment of genes with functions related to cholesterol biosynthesis, IGF-1 signalling, insulin receptor/secretion signalling, androgen signalling and Sertoli cell junction signalling.
