Project description:dairy goats represent a crucial species within global dairy livestock. In temperate regions with distinct seasons, dairy goats exhibit reduced reproductive activity under long photoperiod conditions—a phase termed the non-breeding season. This poses a significant challenge to sustaining year-round goat milk production. As the pivotal organ for reproduction, the molecular regulatory mechanisms of the ovary in seasonal breeding remain incompletely characterized. This study investigated the variations in gonadotropin levels in dairy goats across breeding and non-breeding seasons, alongside an evaluation of follicle size and quantity. Furthermore, ovarian differences were explored at the molecular level using transcriptomic and proteomic methodologies. The findings indicate that follicle stimulating hormone (FSH) and luteinizing hormone (LH) levels in dairy goats are significantly reduced during the non-breeding season compared to the breeding season (p < 0.05). Furthermore, follicle sizes in dairy goats are notably larger during the breeding season relative to the non-breeding season (p < 0.05). A total of 1,115 differentially expressed genes (DEGs) were identified, comprising 749 upregulated and 366 downregulated genes. Additionally, 520 differentially expressed proteins (DEPs) were identified, with 162 upregulated and 358 downregulated. The identified common DEGs and DEPs exhibiting consistent expression patterns include TMEM205, TM7SF2, SLC35G1, GSTM1, and ABHD6. These DEGs and DEPs suppress follicular development during the non-breeding season by regulating steroid hormone biosynthesis. In conclusion, these results offer novel insights into the seasonal reproductive mechanisms of dairy goats.
Project description:Alpine goat phenotypes for quality components have been routinely recorded for many years and deposited in the Council on Dairy Cattle Breeding (CDCB) repository. The data collected were used to conduct an exploratory genome-wide association study (GWAS) from 72 female Alpine goats originating from locations throughout the U.S. Genotypes were identified with the Illumina Goat 50K single nucleotide polymorphisms (SNP) Beadchip. The analysis used a polygenic model where the dropping criteria was the Call Rate ≥ 0.95. The initial dataset was composed of ~ 60,000 rows of SNPs, 21 columns of phenotypic traits and composed of 53,384 scaffolds containing other informative data points used for genomic predictive power. Phenotypic association with the 50KBeadchip revealed 26,074 reads of candidate genes. These candidate genes segregated as separate novel SNPs and were identified as statistically significant regions for genome and chromosome level trait associations. Candidate genes associated differently for each of the following phenotypic traits: test day milk yield (13,469 candidate genes), test day protein yield (25,690 candidate genes), test day fat yield (25,690 candidate genes), percentage protein (25,690 candidate genes), percentage fat (25,690 candidate genes), and percentage lactose content (25,690 candidate genes). The outcome of this study supports elucidation of novel genes that are important for livestock species in association to key phenotypic traits. Validation towards the development of marker-based selection that provide precision breeding methods will thereby increase breeding value. Specific aims: 1) Improve on contributions to the phenotype repository, the Council on Dairy Cattle Breeding (CDCB) for milk quality traits that are economically important for goat production while developing a corresponding DNA repository for each of the animals with significant genotype-phenotype associations. 2) Develop genomic prediction tools and provide data for a better database for tools to predict phenotypic traits by initially using the high density Goat50KSNP BeadChip for the selection of more specific SNPs associated with select signatures (genes) for phenotypic traits in American Alpine goats. 3) To establish whether a low number of goat subjects (< 300 goats) will provide statistically significant (p < 0.05) predictive capabilities for desired breeding traits in American Alpine dairy goats.
Project description:The mammary gland redeveloped to the pre-pregnancy state during involution, which shows that the mammary cells have the characteristics of remodeling. The rapidity and degree of mammary gland involution are different between mice and dairy livestock (dairy cows and dairy goats). However, the molecular genetic mechanism of involution and remodeling of goat mammary gland has not yet been clarified. Therefore, this study carried out the RNA-sequencing of nonlactating mammary gland tissue of dairy goats in order to reveal the transcriptome characteristics of nonlactating mammary tissues and clarify the molecular genetic mechanism of mammary cell involution and remodeling.
Project description:The mammary gland redeveloped to the pre-pregnancy state during involution, which shows that the mammary cells have the characteristics of remodeling. The rapidity and degree of mammary gland involution are different between mice and dairy livestock (dairy cows and dairy goats). However, the molecular genetic mechanism of miRNA in involution and remodeling of goat mammary gland has not yet been clarified. Therefore, this study carried out the RNA-sequencing of nonlactating mammary gland tissue of dairy goats in order to reveal the transcriptome characteristics of miRNA in nonlactating mammary tissues and clarify the molecular genetic mechanism of miRNA in mammary cell involution and remodeling.
Project description:The present study, for the first time, compared the transcriptomes of ovaries from the prolific Jintang black goat and the non-prolific Tibetan goat during follicular phase using the Illumina RNA-Seq method. The study provides insight into the transcriptional regulation in the ovaries of two distinct breeds of goats that might serve as a key resource for understanding goat fecundity.
Project description:In dairy ruminants transcriptome profiling has enabled the identification of genes, pathways and regulatory networks activated in mammary tissues during experimental infection by various pathogens, including E. coli, S. aureus and S. uberis. Information in goats are still low and many host-pathogen interaction mechanisms have to be explained. The objectives of the present study were (1) to identify the network of genes that becomes activated in caprine blood and milk somatic cells in early response towards a S. aureus challenge in order to better understand the local and sistemic response and (2) to search any difference in this immune response by using two animal groups belonging to a caprine reference family established based on founders with adverse SCC breeding values. Udders from ten healthy French Alpine goats were infected with S. aureus and samples of blood and milk cells were collected at 0, 24 and 30 hours after infection. Alterations in the transcriptome profile were investigated using a custom bovine DNA microarray containing 43.822 unique gene probes.
Project description:Staphylococcus aureus is recognized worldwide as a major pathogen causing clinical or subclinical intramammary infections in all the dairy species (sheep, goats and cows). The present study was designed to comparatively investigate 65 S. aureus isolates recovered from dairy sheep and S. aureus suclinical mastitis from cows (n=21) and goats (n=22), for the presence of 190 putative virulence determinants with a single-dye DNA microarray and PCR. The probes (65 mer) were mainly designed from the S. aureus Mu50. The extracted DNA of each strain was labelled with Cy5. The microarray results were validated with PCR.The genomic comparative study with the DNA microarrays showed lineage and species specificity genes leading to the host-specific pathogenic traits of S. aureus in dairy species.
Project description:Guard hair and cashmere undercoat are developed from primary and secondary hair follicle, respectively. Little is known about the gene expression differences between primary and secondary hair follicle cycling. In this study, we obtained RNA-seq data from cashmere and milk goats grown at four different seasons. We studied the differentially expressed genes (DEGs) during the yearly hair follicle cycling, and between cashmere and milk goats. WNT, NOTCH, MAPK, BMP, TGFβ and Hedgehog signaling pathways were involved in hair follicle cycling in both cashmere and milk goat. However, Milk goat DEGs between different months were significantly more than cashmere goat DEGs, with the largest difference being identified in December. Some expression dynamics were confirmed by quantitative PCR and western blot, and immunohistochemistry. This study offers new information sources related to hair follicle cycling in milk and cashmere goats, which could be applicable to improve the wool production and quality.
Project description:Five healthy Laoshan dairy goats (four years old, third lactation) from Qingdao Laoshan dairy goat primary farm (Shandong Province, China) were used. The mammary gland samples were collected surgically after general anaesthesia using Xylazine Hydrochloride injection solution (Huamu Animal Health Products Co., Ltd. China) at corresponding lactation stage, including early, peak and late lactations.
Project description:Background: Small ungulates (sheep and goat) display a seasonal breeding, characterised by successive periods of sexual activity (SA) and sexual rest (SR). In sexual activity period the ovarian cycle of females is active and ready for reproduction (oestrus) whereas in sexual rest no ovulation and reproduction are possible (deep anoestrus). Odours emitted by a sexually active male can reactivate the ovarian cycle of anoestrus females. The plasticity of the olfactory system under these hormonal changes has never been explored at the peripheral level of odours reception. As it was shown in pig that the olfactory secretome (proteins secreted in the nasal mucus) could be modified under hormonal control, we monitored its composition in females of both species along several seasons, thanks to a non-invasive sampling of olfactory mucus. Results: In both species the olfactory secretome is composed of isoforms of OBP-like proteins, generated by post-translational modifications, phosphorylation, N-glycosylation and O-GlcNAcylation. Important changes were observed in the olfactory secretome between the sexual rest and the sexual activity periods, characterised in ewe by the specific expression of SAL-like proteins and the emergence of OBPs O-GlcNAcylation. In Goat, the differences between SA and SR did not come from new proteins expression, but from different post-translational modifications, the main difference between the SA and SR secretome being the number of isoforms of each protein. Conclusion: Despite common behaviour, seasonal breeding, and genetic resources, the two species seem to adapt their sensory equipment in SA by different modalities: the variation of olfactory secretome in ewe could correspond to a specialization to detect male odours only in SA, whereas in goat the stability of the olfactory secretome could indicate a constant capacity of odours detection suggesting that the hallmark of SA in goat could be the emission of specific odours by the sexually active male.