This project aims to investigate the effects of feed timing on fish growth, immune gene expression and rhythmicity of gut microbiota to provide a new understanding of how feed timing can be better used to enhance fish health and welfare, and increase UK aquaculture sustainability and productivity.
This project aimed to assess the impact of timed feeding strategies on the growth of rainbow trout, and the daily rhythmicity of their gene expression and gut microbiota.
We compared the growth rates of trout fed using one of the following timed feeding treatments: four feeds only early in light cycles (morning treatment), four feeds only late in light cycle (evening treatment), four feeds spread throughout light cycle (all day treatment), four feeds given randomly each day (random treatment). We found that providing food rations only in early in the light cycle has a significant negative impact on growth. In addition, we found feeds spread regularly throughout light cycle resulted in the lowest individual variation in final weights/lengths and highest specific growth rates.
We demonstrate feed timing has a substantial impact on the rhythmic expression of clock, metabolic and immune genes in trout intestines. Randomly fed fish have fewer rhythmic genes and we find significant differences in peaks of expression between morning and afternoon feed treatments. For the first time, we demonstrate fish gut microbiota have daily cycles in their relative abundance and their temporal patterns are shifted by feed time. Taken together, these results demonstrate the importance of feed timing on fish health and provide vital new information to direct chronotherapeutic strategies in aquaculture for reducing health issues and enhancing productivity.