Abstract
INTRODUCTION: Climate change poses a significant environmental challenge to all living organisms. Camels exhibit notable resilience to these changes. Concurrently, the date palm (Phoenix dactylifera), a widely cultivated plant in tropical and subtropical regions, generates substantial seed waste. Valorizing Phoenix dactylifera seed-derived biochar (PSB) to enhance feed supplements and mitigate environmental impacts presents a potentially sustainable and eco-friendly solution. This study investigated the potential of date palm seed-derived biochar as a sustainable feed additive for dromedary camels to reduce methane (CH₄) emissions and improve gas production, nutrient degradability, fermentation parameters, and performance predictions using in vitro models. METHODS: The PSB was synthesized and stored at 4°C until use. Ruminal fluids were collected from growing camels (24-36 months old) at the nutrition laboratory and subsequently incubated at 37°C. The basal diet was supplemented with PSB at 0, 1, 2, and 4%, and the resulting data were analyzed using polynomial analysis. Gas production, methane emissions, nutrient degradability, fermentation parameters, and performance predictions were assessed. RESULTS: At 6, 12, and 36 hours of incubation, all levels of PSB biochar supplementation resulted in a significant linear increase in gas production (p < 0.05). The inclusion of PSB significantly reduced CH₄ emissions in a quadratic manner (p < 0.001). The lowest reduction in CH₄ production was observed at the 1% and 2% PSB inclusion levels, with a greater reduction at the 4% level (quadratic effect; p < 0.001). A significant quadratic increase in TVFA production was observed with increasing PSB inclusion levels during the in vitro fermentation of camel diets (quadratic effect; p < 0.01). Furthermore, pH values significantly decreased with biochar supplementation, exhibiting a linear trend with the lowest values at the 4% level, followed by 2% and 1% (linear effect; p < 0.01). Short-chain fatty acid (SCFA) production was improved by the addition of PSB compared to the control diet in camels (quadratic effect; p < 0.01). The inclusion of 1% or 2% PSB quadratically improved organic matter digestibility (%), metabolizable energy (DM), and net energy for lactation (NEL) in camels. Microbial crude protein (MCP) and purine derivatives (PD) were not significantly affected by PSB supplementation (p > 0.05). CONCLUSION: In summary, the addition of PSB enhanced gas production, nutrient degradability, fermentation parameters, and performance predictions, while concurrently mitigating methane emissions in vitro. This study underscores the potential of utilizing PSB as a valuable feed supplement and a sustainable feed additive for dromedary camels in extensive production systems.