RNA-seq analysis of hoof tissue transcriptome in dairy cows affected by sole ulcer

Lameness is a common illness in dairy cows, and sole ulcers are the major cause of lameness. The objective of this study was to evaluate the transcriptional changes of the hoof (or corium) tissue of lactating dairy cows diagnosed with sole ulcer. Hoof biopsies were performed in multiparous Holstein cows selected based on their condition as clinically healthy (HC) or diagnosed with sole ulcers (SU)(n = 6/group). Hoof samples were collected under local anesthesia from the sole of the hoof in claw zone 4. Total RNA extracted from tissue was sequenced and analyzed for differential gene expression using DESeq2. Blood biomarkers confirmed that sole ulcer conditions heightened a systemic inflammation associated with decreased liver function. The majority of downregulated genes in SU cows were rich-cysteine keratins or hard keratins and high-sulfur KAPs, which may indicate a significant reduction in the incorporation of sulfur-containing AA in hoof tissue may predispose cows to sole ulcers.