Impacts of Wild Olive (Olea europaea) Leaf Supplementation on Milk Yield and Composition in Beetal Goats

Abstract

Introduction: Sustainable feeding strategies are critical for improving small ruminant productivity in regions facing forage scarcity. Wild olive (Olea europaea) foliage, is rich in protein, minerals, and bioactive compounds, making it a potential unconventional feed resource. This study aimed to evaluate the impact of wild olive leaf supplementation on nutrient intake, digestibility, milk yield and composition, and blood biochemical parameters in lactating Beetal goats.

Methods and materials: Sixteen lactating Beetal goats with average age of 3 years and body weight of 35–40 kg were randomly assigned to four dietary treatments containing 0% (Control), 5%, 10%, or 15% wild olive leaves on a dry matter (DM) basis. Wild olive leaves were chopped and incorporated directly into the basal feed ration, offered twice daily with free access to clean drinking water. Feed intake, digestibility, milk yield and composition, blood biochemistry, and mineral concentrations were measured over a six‑week trial.

Results: Compared to the control group (0% wild olive leaves), goats fed 15% wild olive leaves showed the highest nutrient intake and digestibility values. Milk yield increased significantly in the group fed 15% olive leaves (2.08 L/day) compared to the control group (1.46 L/day), with corresponding improvements in fat, protein, lactose, and mineral fractions. Blood biochemical indices remained within physiological ranges across all groups, but goats fed 15% wild olive leaves exhibited higher total protein and albumin levels and lower cholesterol concentrations compared to group control.

Conclusion: Wild olive leaves can be effectively included in goat diets at up to 15% dry matter. The inclusion of 15% level of Wild olive to the goat’s diet yielded the highest nutrient intake, digestibility, and milk yield compared to the control group.