Feed efficiency, i.e. the efficiency with which livestock utilize their feed for net production, is a useful measure of performance in aquaculture and agricultural settings. As feed typically represents the single biggest cost of production, there is a strong financial incentive to improve the feed conversion ratio (FCR) through selective breeding and the optimization of animal health and nutrition. Animals with a high FCR have been shown to produce less waste than those with poor feed efficiency, highlighting an opportunity to lessen the environmental impact.
Recent studies have identified differences in the microbiome composition across high- and low-feed efficient animals, raising an obvious question: how can we manipulate the animal microbiome to improve feed efficiency? Feed quality, micronutrient availability and immune status are well-known modulators of FCR, while modern microbiome research has spurred the development of probiotics and digestive enzymes to improve gastrointestinal function.