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 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: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: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:Dietary supplementation with fish-oil modulates ruminant milk composition towards a healthier fatty acid profile for consumers, but it also causes milk fat depression (MFD). Because the dairy goat industry is mainly oriented towards cheese manufacturing, MFD can elicit economic losses. There is large individual variation in animal susceptibility with goats more (RESPO+) or less (RESPO−) responsive to diet-induced MFD. Thus, we used RNA-Seq to examine gene expression profiles in mammary cells to elucidate mechanisms underlying MFD in goats and individual variation in the extent of diet-induced MFD.
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:In the present study, RNA-seq technique was used to compare the expression profiles of circRNAs from goat endometrium samples at gestational day 5 (pre-receptive endometrium, PE) and day 15 (receptive endometrium, RE). A total of 21,813 circRNAs were identified in goat endometrium, of which only 31.22% (6,810) circRNAs were co-expressed at both stages, and 5,925 circRNAs were identified specifically in RE and 9,078 in PE, suggesting high stage specificity in the circRNAs in dairy goats. Further analysis found that there were 334 DECs (differentially expressed circRNAs) in RE compared to PE (P< 0.05), and circRNA8077 was up-regulated with the highest FPKM value in RE. It was noteworthy that half of the up-regulated circRNAs with top 10 highest FPKM value in RE were come from CRIM1. Moreover, GO and KEGG analysis of the hgDEGs (hosting genes of DECs) revealed some circRNAs, genes and pathways that may involve in the formation of the receptive endometrium in dairy goats. In a word, our data provided an endometrium circRNA expression atlas related to the biology of the goat receptive endometrium during embryo implantation, and the results suggested that a subset of circRNAs might involve in the processes of the formation and development of endometrial receptivity.
Project description:In this study, we investigated the molecular regulatory mechanisms of milk protein production in dairy cows by studying the miRNAomes of five key metabolic tissues involved in protein synthesis and metabolism from dairy cows fed high- and low-quality diets. In total, 340, 338, 337, 330, and 328 miRNAs were expressed in the rumen, duodenum, jejunum, liver, and mammary gland tissues, respectively. Some miRNAs were highly correlated with feed and nitrogen efficiency, with target genes involved in transportation and phosphorylation of amino acid (AA). Additionally, low-quality forage diets (corn stover and rice straw) influenced the expression of feed and nitrogen efficiency-associated miRNAs such as miR-99b in rumen, miR-2336 in duodenum, miR-652 in jejunum, miR-1 in liver, and miR-181a in mammary gland. Ruminal miR-21-3p and liver miR-2285f were predicted to regulate AA transportation by targeting ATP1A2 and SLC7A8, respectively. Furthermore, bovine-specific miRNAs regulated the proliferation and morphology of rumen epithelium, as well as the metabolism of liver lipids and branched-chain AAs, revealing bovine-specific mechanisms. Our results suggest that miRNAs expressed in these five tissues play roles in regulating transportation of AA for downstream milk production, which is an important mechanism that may be associated with low milk protein under lowquality forage feed.