Mitigation of Carbon Emissions and Enhancement of Lactational and Physiological Indices in West African Dwarf Does Using Daniella oliveri Essential Oil-Based Diets

Abstract

This study evaluated the effects of Daniella oliveri essential oil (DOE) supplementation on enteric methane production, milk yield, immune response, and oxidative stress indicators in lactating West African Dwarf (WAD) does. Twenty-one does with comparable initial body weights (10.55 ± 0.60 kg) were randomly allotted to three dietary treatment groups (n = 7) using a completely randomized design over a 50-day feeding period. Dietary supplementation with DOE significantly improved (P < 0.05) milk yield, serum immunoglobulins (IgG, IgA, and IgM), triiodothyronine (T3), and superoxide dismutase (SOD) activity, with the highest responses observed in does fed the highest DOE inclusion level (T3). Antioxidant status was also enhanced, as evidenced by significant increases (P < 0.05) in catalase, glutathione peroxidase, glutathione reductase, and total antioxidant capacity in the T2 and T3 groups. Conversely, enteric methane emissions, malondialdehyde (MDA), and cortisol concentrations were significantly reduced in DOE-supplemented animals relative to the control group (P < 0.05). The results indicate that DOE supplementation enhances lactational performance, strengthens immune function, and improves oxidative stability while concurrently reducing methane emissions, demonstrating its potential as a climate-smart nutritional strategy for sustainable dairy goat production. Based on the observed responses, supplementation at 10 ml DOE/kg diet was considered the optimal inclusion level for improving productivity and physiological wellbeing in WAD does.