Tithonia diversifolia as a multifunctional forage for ruminants: Nutritional value, fermentation, methane mitigation, and environmental sustainability

Abstract

Background and Aim: Tithonia diversifolia, commonly known as wild sunflower, is an underutilized tropical forage with considerable potential to support ruminant nutrition and environmentally sustainable livestock production, particularly in tropical and resource-limited regions. This review synthesizes current evidence on the nutritional characteristics, processing and fermentation technologies, effects on animal performance, methane mitigation potential, and environmental applications of T. diversifolia, while integrating these attributes within a climate-smart silvopastoral framework. Relevant literature was identified through searches of major scientific databases using combinations of keywords related to T. diversifolia, ruminant nutrition, fermentation, digestibility, animal performance, rumen fermentation, methane, soil, and sustainable livestock production, followed by screening of relevant studies. T. diversifolia generally contains relatively high crude protein content, commonly ranging from 20% to 25% of dry matter, together with nutritionally important minerals such as calcium and phosphorus. However, its utilization may be constrained by anti-nutritional compounds, including phytic acid, tannins, and oxalates, as well as variation associated with plant maturity, environmental conditions, and processing methods. Fermentation, particularly with lactic acid bacteria, offers a promising strategy for reducing selected anti-nutritional factors and improving nutrient availability, digestibility, preservation, and palatability. Animal feeding studies indicate that T. diversifolia can partially replace conventional feed resources and may support nutrient intake, digestibility, growth and milk production, although responses vary among animal species, inclusion levels, and experimental conditions. In vitro studies further indicate that its secondary metabolites, particularly tannins and saponins, can modify rumen fermentation and may reduce methane production under specific experimental conditions; however, evidence for consistent methane mitigation in vivo remains limited. Beyond its nutritional functions, its high biomass production, adaptability, and potential for nutrient recycling of T. diversifolia suggest possible applications in sustainable silvopastoral systems and soil management, although direct evidence for soil restoration and broader ecosystem services remains comparatively limited. The current evidence base is constrained by heterogeneity in plant material, nutritional composition, processing methods, inclusion levels, animal species, experimental designs, and outcome measurements, together with a limited number of long-term in vivo and field studies. Future research should prioritize optimization of fermentation technologies, long-term in vivo evaluation, elucidation of rumen microbiome and methane mitigation mechanisms, life cycle and economic assessments, and region-specific feeding strategies. Overall, T. diversifolia shows promise as a multifunctional tropical forage, but stringer and more standardized in vivo and field-based evidence us needed to establish its contributions to animal performance, methane mitigation, soil improvement, and broader ecosystem services. Keywords: alternative forage, climate-smart livestock, enteric methane, fermentation, ruminant nutrition, silvopastoral systems, sustainable livestock, Tithonia diversifolia.