Chaya (Cnidoscolus aconitifolius) in Ruminant Nutrition: Nutritional Value, Bioactive Compounds, Safety and Prospects for Goat Feeding

Abstract

Goat production in tropical and subtropical regions is frequently constrained by seasonal feed scarcity, low-quality forages and increasing feed costs, creating interest in alternative perennial feed resources. Chaya (Cnidoscolus aconitifolius) is a protein-rich shrub traditionally used as a leafy vegetable and has potential as a non-conventional feed resource for ruminants. This review critically synthesises available evidence concerning the botanical characteristics, nutritional composition, bioactive compounds, anti-nutritional factors, processing, rumen fermentation, nutrient utilisation and productive responses associated with chaya feeding, with particular emphasis on evidence relevant to goats. Available compositional studies indicate that chaya leaf material can contain relatively high crude protein concentrations, although nutrient composition varies with plant fraction, maturity, cultivar and growing conditions. In vitro and in vivo studies in cattle indicate that chaya supplementation can modify rumen fermentation and nutrient utilisation, while studies in growing goats have also demonstrated that chaya fodder or foliage can be incorporated into diets without adverse effects on feed intake, nutrient digestibility or growth at the evaluated inclusion levels. However, the goat-specific evidence base remains small and is focused primarily on growing animals, feed intake, digestibility and growth performance. Evidence concerning lactating goats, milk composition, long-term safety, reproductive responses, rumen microbiome, direct methane emissions and farm-scale economic and environmental effects remains limited. In particular, changes in rumen fermentation should not be interpreted as demonstrated methane mitigation in the absence of direct in vivo methane measurements. Overall, chaya represents a promising non-conventional feed resource, but further controlled goat feeding trials, dose-response studies, safety evaluation and mechanistic investigations are required before generalised feeding recommendations can be established.