Physicochemical characteristics, in vitro ruminal digestibility, bioactive compounds, and estimated methane production of wild floral species in goats from the republic of Malta : a descriptive study

Abstract

Goats and other ruminants produce methane during digestion, contributing to greenhouse gas emissions and reducing feed efficiency. This study evaluated 32 wild terrestrial plant species from Malta to determine their nutritional composition, antioxidant activity, and potential influence on methane production in goats. Crude protein levels ranged widely among species, with several plants exceeding 25% dry matter and the highest values approaching 32%. Fibre content also varied substantially, with neutral detergent fibre ranging from approximately 12% to 49%. Polyphenol concentrations ranged from 0.07% to 1.30% (w/w), while antioxidant activity differed markedly between species, with IC50 values from 0.37 to 55.9 mg/mL. In vitro methane production after 48 h ranged from about 30 to 198 L CH4 kg⁻¹ depending on the plant species. These results demonstrate that several local plants combine favourable protein content, moderate fibre levels, and bioactive compounds that may influence rumen fermentation and methane formation. The findings identify underutilized Maltese plant species that warrant further evaluation as supplementary feed resources for goats, although in vivo studies are needed before their use can be recommended in practice.