DOI: 10.11118/978-80-7701-093-1-0040

ESSENTIAL OILS AND FATTY ACIDS AS SILAGE ADDITIVES: A REVIEW

Nussio, L. G.¹, Silva Neto, Á. B. de.¹, Morais, G.², Ribeiro, A. P.¹, Ferreira, E. M.¹

¹ Department of Animal Science, University of São Paulo, Piracicaba, SP, Brazil

² Empresa de Pesquisa Agropecuária e Extensão Rural de Santa Catarina - EECN/Epagri, Campos Novos, SC, Brazil

Abstract The search for natural alternatives to conventional silage additives has stimulated interest in plant-derived compounds capable of modulating microbial activity during ensiling. This review aimed to compile and critically analyse the available literature on the use of essential oils and fatty acids as additives in silage production. A systematic search of major scientific databases identified 28 studies evaluating essential oils applied to a variety of forage silages, whereas information on fatty acids was extremely limited. Most experiments tested crude plant essential oils, frequently with incomplete descriptions of their chemical composition, and only a few studies evaluated individual bioactive compounds. Overall, the responses to essential oil application varied considerably depending on the forage species, oil composition, application rate and storage conditions. Alfalfa silage appeared to respond more consistently to several essential oils, with reports of enhanced lactic acid production, reduced proteolysis and improved aerobic stability. In whole-plant corn silage, the most consistent effect across studies was the improvement of aerobic stability, whereas impacts on fermentation quality were variable and occasionally suggested compromised acidification. For other forage types, results were inconsistent and often limited by experimental design or lack of microbiological data. The literature on fatty acids as silage additives remains scarce, although available evidence suggests that these compounds may exert selective antimicrobial pressure capable of influencing fermentation processes. Overall, current knowledge remains insufficient to establish clear recommendations for the use of these compounds in silage systems. Future research should prioritise the evaluation of individual bioactive molecules rather than crude oils, incorporate molecular approaches to characterise microbial modulation, and include detailed assessments of the early fermentative phase to better understand the mechanisms through which these compounds influence silage fermentation and preservation.

Klíčová slova: aerobic stability, essential oils, fatty acids, silage, additives

stránky: 40-63, Publikováno: 2026, online: 2026