Objective: This study aimed to investigate the meat quality attributes and expression patterns of meat quality-regulating genes of two Indian indigenous sheep breeds.
Methods: Meat quality indicators and expression patterns of four candidate genes (CAST, CAPN, CEBPB, SCD), involved in meat tenderness, intramuscular fat (IMF) and fatty acid (FA) composition in the longissimus dorsi muscle of healthy rams of Nellore (n=4) and Deccani (n=4) sheep breeds aged between 9-12 months, were measured.
Results: The Nellore breed exhibited lower cooking loss, pH, moisture, and shear force, and higher protein. The Nellore breed exhibited higher crude protein content (p<0.05), while the Deccani breed showed higher crude fat content (p<0.05) and moisture (p<0.05). Further, fatty acid composition varied among breeds, with the Deccani breed exhibiting a healthier profile than the Nellore breed. Relative expression of the CAST, SCD and CEBPB genes was 5.51, 3.04, and 3.08-fold higher in the Deccani breed (p<0.05) compared to the Nellore breed, respectively. Significant correlations were observed between gene expression and meat quality traits. The IMF and FA composition demonstrated a strong positive correlation (p<0.05) with CEBPB and SCD expression. Moreover, in the Nellore breed, WBSF exhibited a strong negative correlation (p<0.05) with CAPN expression.
Conclusion: This study demonstrated clear differences between the two sheep breeds evaluated under extensive feeding systems. The Deccani breed offers superior IMF and flavour potential, along with a high amount of desirable fatty acids. Conversely, the Nellore breed's balanced proteolytic activity and leaner composition made it favourable for tenderness.
Keywords: Fatty acid composition; Intramuscular fat content; Meat quality; Nellore and Deccani; meat quality regulating genes.