Potential Complementary Modulation of Rumen Fermentation and Lipid Metabolism in Sheep: A Hypothesis Framework for Fermented Chinese Chive Juice and Black Soldier Fly-Derived Fatty Acids

Chinese chive (<i>Allium tuberosum</i>), an edible and medicinal herb, has attracted attention for its distinctive flavor and bioactive potential. Evidence indicates that fermentation can enhance its antimicrobial and antioxidant activities, and fermented preparations have been explored as feed additives to reduce reliance on antibiotics in poultry. By contrast, evidence in ruminants-particularly sheep-remains limited, and the metabolic consequences of Chinese chive-derived compounds are not yet well defined. In parallel, fatty acids from black soldier fly (<i>Hermetia illucens</i>) larvae, with lauric acid as a prominent component, have been reported to influence rumen fermentation and aspects of lipid metabolism, suggesting a possible route to improve product traits. This review synthesizes the literature on Chinese chive and BSFL fatty acids, critically appraises how their constituents may relate to sheep nutritional metabolism, and advances a hypothesis that fermented Chinese chive juice (FCCJ) could complement black soldier fly larvae-derived fatty acids (BSFL-FA) in regulating rumen fermentation, lipid metabolism, and product quality in sheep. While the literature supports plausible complementarity, direct evidence for synergy in ruminants is still scarce and should be tested through controlled in vitro screening and well-designed in vivo sheep studies.