Transcriptomic Insights Into Gene Expression Differences Between High And Low Milk Producing Dairy Cows

Abstract

The underlying molecular pathways must be thoroughly understood to improve milk output in dairy cows. This investigation examines how the blood gene expression patterns of dairy cows with very high and low milk production differ from one another. Ribonucleic acid sequencing (RNA-seq) is performed on blood samples from 35 lactating dairy cows, identifying 50 Differentially Expressed Genes (DEGs) (p < 0.05) between the two groups. Functional enrichment analysis reveals that these DEGs primarily involve immune response, inflammatory processes, fatty acid metabolism, and security mechanisms. According to KEGG pathway analysis, the Toll-like receptor (TLR) signalling pathway is the most purposefully created pathway associated with variance in milk output. Using (Quantitative Reverse Transcription Polymerase Chain Reaction) qRT-PCR to validate four sample DEGs, the consistency of the RNA-seq data is validated. Alternative splicing analysis demonstrates distinct splicing patterns between the groups, with alternative 3′ splicing sites predominating in high-yielding cows, while exon skipping is more frequent in low-yielding cows. These findings provide novel transcriptomic insights into gene expression differences linked to milk production and emphasize the contribution of immune-related pathways. The research identifies potential molecular markers that can support non-invasive genetic selection strategies to improve dairy cattle productivity.