Phytogenic and Nutritional Strategies to Improve Milk Production and Microbiological Quality in Lactating Donkeys

Donkey milk is highly regarded for its nutritional, immunological and hypoallergenic properties. In this context, the global demand is increasing and the challenges of low production and milk hygiene need to be addressed. This study evaluated the effects of dietary and phytogenic supplementation on milk yield, nutrient digestibility, and milk quality in lactating jennies (Equus asinus). A total of 30 animals were allocated to three groups (n = 10 per group): a control group (CG) fed pasture grass and corn; Group 1 (G1), receiving a diet enriched with sunflower meal and a phytogenic blend of medicinal plants; and Group 2 (G2), receiving the same compound feed without phytogenic additives. Over an eight-week period, milk production, apparent digestibility coefficients (dry matter, protein, fibre, and ether extract), and microbiological quality were assessed. G1 demonstrated the highest milk yield (p < 0.001), improved nutrient digestibility (e.g., crude protein digestibility: 57.89 ± 4.21%), and a significant reduction in total viable counts (TVC) from 2.848 ± 0.265 to 1.898 ± 0.404 log₁₀ CFU/mL (p < 0.001), compared to CG and G2. The phytogenic supplement stabilized milk chemical composition, suggesting potential galactagogues, immunomodulatory, and antimicrobial effects. These findings support the use of functional feed additives as a promising strategy to enhance productive performance and milk hygiene in sustainable donkey farming systems.