Evaluating the efficacy of a novel multi-component feed additive for methane mitigation and performance enhancement in sheep

Enteric methane emissions from ruminants significantly contribute to global greenhouse gas emissions, necessitating effective mitigation strategies that also support animal productivity. This study assessed the efficacy of NuAdvent+, a novel feed additive combining medium-chain fatty acids (MCFAs), live yeast, plant-based agents, and Vitamin B, in reducing methane emissions, improving feed efficiency, and enhancing growth and immune function in sheep. Twenty crossbred castrated male sheep (52 ± 3.7 kg) were divided into control and treatment groups (n = 10 each), with the treatment group receiving grass pellets supplemented with NuAdvent+ (20 g/day) for 71 days, including a 30-day acclimatisation period. Feed intake, methane emissions, growth performance, and blood parameters were monitored using BioControl pens, GreenFeed units, and haematological analyses. The treatment group exhibited a 24% increase in daily feed intake (p < 0.001) and a 22.2% reduction in methane yield per kg of dry matter ingested (p < 0.001), attributed to MCFAs’ anti-methanogenic properties and yeast’s rumen modulation. However, no significant improvements were observed in daily live weight gain, feed conversion efficiency, or immune markers, suggesting limited energy utilisation for growth. These findings highlight NuAdvent+ as a promising tool for methane mitigation in forage-based systems, though its benefits are tempered by trade-offs in fibre digestibility and productivity. Further optimisation of dosage and dietary integration could enhance its application across ruminant species, contributing to sustainable livestock production.