Combined Effects of Sodium Bentonite, Moringa oleifera, and Red Seaweed on In Vitro Rumen Fermentation and Methane Mitigation

This research aimed to study the effect of a combination of three natural feed additives sodium bentonite, Moringa oleifera, and red seaweed (Jania granifera) mixtures on in vitro rumen fermentation, methane mitigation, enzyme activity, and microbial population dynamics in Baladi sheep. Rumen fluid was incubated in gas-tight syringes with feed supplemented with mixes of additives for 24 hours. Key parameters assessed included total gas and methane production, pH, ammonia levels, total and individual volatile fatty acids (VFAs), cellulase activity, microbial biomass, and microbial efficiency. The relative abundance of total bacteria, cellulolytic bacteria, and methanogenic archaea was quantified using qPCR. Moringa oleifera and bentonite mixture increased gas production, microbial yield, and acetate molar proportions. As well as maintaining high cellulase activity, indicating enhanced microbial growth, but showed a decent reduction in methane (nearly 15%). Red seaweed & bentonite mixed supplementation significantly reduced methane production by approximately 39% and methanogenic archaea abundance to 0.25-fold compared to the control, but it decreased total VFAs and cellulase activity. The seaweed & moringa mixed treatment showed a satisfactory methane reduction (30%) with high digestibility and fermentation efficiency, rendering it the best choice for balanced rumen fermentation among the previous groups. These findings highlight the potential of these additives to optimize rumen fermentation and reduce methane emissions.