Physicochemical and microbiological quality of raw cow milk across agro-ecological zones in Jarso District, Eastern Ethiopia

Improving the physicochemical characteristics and microbial safety of raw milk is essential for strengthening Ethiopia’s dairy supply chain, yet information on how agro-ecological conditions influence milk quality remains limited. This study evaluated the physicochemical properties and microbial quality of raw cow milk collected from three agro-ecological zones in Jarso District, eastern Ethiopia. Seventy milk samples were analyzed using standard dairy analytical procedures. Agro-ecology significantly influenced ( p < 0.05) most physicochemical properties and microbial quality parameters. Highland milk had superior nutritional composition, whereas lowland and midland milk exhibited higher microbial contamination. In contrast, solids-not-fat, lactose, and yeast and mold counts were not significantly affected ( p > 0.05). These findings demonstrate that agro-ecological variation influences both the compositional and microbial quality of raw milk and highlight the need for agro-ecology-specific hygienic milking and milk handling practices to improve milk quality and safety.