Project description:This study presents a dynamic characterization of the sheep milk transcriptome aiming at achieving a better understanding of the sheep lactating mammary gland. Transcriptome sequencing (RNA-seq) was performed on total RNA extracted from milk somatic cells from ewes on days 10, 50, 120 and 150 after lambing. The experiment was performed in Spanish Churra and Assaf breeds, which differ in their milk production traits. Nearly 67% of the annotated genes in the reference genome (Oar_v3.1) were expressed in ovine milk somatic cells. For the two breeds and across the four lactation stages studied, the most highly expressed genes encoded caseins and whey proteins. We detected differentially expressed genes (DEGs) across lactation points, with the largest differences being found, between day 10 and day 150. Upregulated GO terms at late lactation stages were linked mainly to developmental processes linked to extracellular matrix remodeling. A total of 256 annotated DEGs were detected in the Assaf and Churra comparison. Some genes selectively upregulated in the Churra breed grouped under the endopeptidase and channel activity GO terms. These genes could be related to the higher cheese yield of this breed. Overall, this study provides the first integrated overview on sheep milk gene expression.
Project description:Milk can mediate maternal-neonatal signal transmission by the bioactive component-extracellular vesicles (EVs), which select specific types of miRNA to encapsulate. The miRNA profiling of sheep milk EVs was characterized by sequencing and compared with that of cow milk. Sheep milk EVs contained various small RNAs, including tRNA, Cis-regulatory element, rRNA, snRNA, other Rfam RNA, and miRNA, which held about 36% of all the small RNAs. Totally 84 types of miRNAs were annotated with Ovis aries by miRBase (version 22.0) in sheep milk EVs, with 75 shared types of miRNAs in all samples. Fourteen sheep milk EV-miRNAs in the top 20, occupying 98% of the total expression, were immune-related.
Project description:To investigate the molecular bases of diet induced differences in milk composition, we collected milk from mid lactation dairy ewes and after 3 weeks of diet supplementation with extruded linseed. RNAs were isolated from milk somatic cells isolated from milk of 3 sheep and Illumina RNA sequencing was performed to analyze RNA synthesis in these cells.
Project description:Tracking the dairy microbiota from farm bulk tank milk to skimmed milk powder using 16S rRNA gene amplicon sequenicng and shotgun metagenomic sequencing
Project description:The knowledge of the genetic architecture behind feed efficiency would allow to breed more efficient animals maximizing farm profitability and reducing the environmental impact of animal production. This study analyzes high throughput gene expression data from milk samples to determine key genes and biological mechanisms associated to feed efficiency in dairy sheep.A detailed description of the sheep management practices and calculations for the feed efficiency index (FEI) are detailed in 10.3168/jds.2020-19061. For these analyses, we selected animals with divergent FEI values from a group of 40 lactating Assaf ewes. RNA-Seq was performed on milk somatic cell samples from 8 high feed efficiency sheep (H-FE), FEI = −0.29 (SD = 0.23), RFI = −0.16 (SD = 0.25), and 8 low feed efficiency sheep (L-FE), FEI = 0.81 (SD = 0.24), RFI = 0.19 (SD = 0.24)).
Project description:In this study, we applied a proteomics strategy to identify peptides present in sheep milk kefir fermented at different times. We aimed to understand changes in the digestion pattern of milk proteins as well as to identify potential bioactive peptides.
