DGAT1 Gene Expression and its Association with Milk Compositions in Breeds of Cattle under Extensive Management System

This study investigated the expression of the Diacylglycerol O-acyltransferase 1 (DGAT1) gene and its association with milk composition traits among three cattle breeds Red Bororo, White Fulani, and Sokoto Gudali reared under an extensive management system. A total of sixty cows (20 from each breed) were selected. Milk samples were analyzed for fat, protein, mineral content, and amino acid profiles, while DGAT1 gene expression was quantified. Results revealed that breed significantly (p<0.05) influenced DGAT1 gene expression. In Red Bororo, significant (p<0.01) negative correlations were observed between DGAT1 expression and amino acids such as lysine (-0.53), methionine (-0.55), glutamic acid (-0.36), glycine (-0.37), and proline (-0.48), while other amino acids showed significant positive correlations. For White Fulani, all amino acids exhibited non-significant (p>0.05) correlations, though mostly positive, except for a few negative but non-significant relationships. Sokoto Gudali demonstrated a significant positive correlation with lysine (0.32*, p<0.05), while arginine (-0.09) and proline (-0.08) showed significant negative associations (p<0.05); all other amino acids displayed non-significant positive relationships. A strong negative correlation (p<0.01) was observed between DGAT1 expression and milk protein in all breeds—Red Bororo (-0.69), White Fulani (-0.75), and Sokoto Gudali (-0.70). Other milk composition traits also exhibited significant negative associations (p<0.05) with DGAT1 expression, except for phosphorus, which showed non-significant correlations (p>0.05) across all breeds. These findings suggest that DGAT1 gene expression is breed-dependent and influences key milk quality parameters, particularly amino acid profile and protein content, under extensive management systems.