Resumen
Plant extracts have been used over time in traditional medicine, mainly for their antimicrobial activity as well as for their medicinal effects. Plant-derived products contain secondary metabolites that prevent pathogenic microbial growth similar to conventional medicines. These secondary metabolites can enhance animal health and production in a more natural or organic manner and may contribute to the reduction in the use of pharmacological drugs in animal feed, which is of great concern for emerging microbial resistance. Plant secondary metabolites can be cost effective, while improving the production efficiency of ruminants, non-ruminants, and aquatic food animals. Among the plant-derived products is the Yucca schidigera extract (YSE), containing steroidal saponins as their main active component. YSE has multiple biological effects, including inhibition of some pathogenic bacteria, protozoa, and nematodes. YSE is used to control odor and ammonia and consistently enhance poultry production by enhancing intestinal health and function. In pigs, results are as yet inconclusive. In ruminants, YSE works against protozoa, has selective action against bacteria, and reduces the archaea populations; all these effects are reflected in the reduction in emissions of polluting gases, mainly methane, although the effects are not observed in all feeding conditions. These effects of YSE are discussed in this review. YSE has potential as a natural feed additive for sustainable animal production while contributing to the mitigation of contaminant gas emissions.