Bio-based Feed Additives and Metabolic Modulators for Enhanced Productivity: Sustainable Low-Cost Feed Strategies Using Local Biomass Resources for Small Ruminant Production in the Aspirational Districts of West Bengal

The integration of bio-based feed additives and metabolic modulators offers an innovative pathway to enhance small ruminant productivity while reducing feed costs and environmental impacts. This study explores the utilization of locally available biomass resources as bio-functional feed ingredients for sustainable Black Bengal goat production across five aspirational districts of West Bengal—Murshidabad, Birbhum, Malda, Dakshin Dinajpur, and Nadia. A 120-day controlled feeding trial involving 489 goats evaluated feed formulations incorporating sugarcane tops, cassava leaves, sweet potato vines, Leucaena , and Sesbania leaf meals as natural sources of secondary metabolites, antioxidants, and fermentable fibers with metabolic modulating potential. Three dietary treatments were tested: T₁ (conventional concentrate feed), T₂ (50% concentrate replaced with biomass-based mix), and T₃ (70% replacement). Nutrient profiling revealed crude protein levels of 14.6–22.5% and total digestible nutrients (TDN) of 55–65%, confirming biochemical adequacy. Biomass-based diets reduced total feed costs by 28–33% and improved metabolic efficiency indicators such as average daily gain (ADG; up to 16% higher in T₃), feed conversion ratio (FCR), and benefit–cost ratio (BCR; from 1.28 to 1.68). These bio-based feed formulations acted as natural metabolic enhancers, optimizing rumen fermentation and nutrient utilization. The study demonstrates that locally derived biomass can serve as effective bio-additives and metabolic modulators, establishing a climate-resilient, low-cost, and circular bioeconomy model for sustainable goat production in Eastern India.