Tilapia farming based on periphyton as a natural food source

Abstract

Nutrient-rich effluents from aquaculture can be reused to enhance the development of natural food to feed fish in periphyton-based systems. A periphyton-based system is a strategy to increase fish farming efficiency, reducing feed use and effluent disposal. This study aimed to evaluate different types of feeding management in periphyton-based systems to produce Nile tilapia in ponds. To do this, two new production models were compared: (P100–0) Nile tilapia fed 100% of the recommended amount of feed sharing effluent with a tilapia production in a periphyton-based system with no feed input, and (P50–0) Nile tilapia fed 50% of feed plus periphyton sharing effluent with a tilapia production in a periphyton-based system with no feed input. Fish fed only feed showed higher growth performance than those fed partially feed plus periphyton. On the other hand, fish only periphyton-based fed grew similarly when using effluent from a system fed only feed and fed partially feed plus periphyton. Biomass gain and productivity were significantly higher in P100–0 than in P50–0, and no differences in the feed conversion ratio and survival were found. For both production models, fish feed fed and periphyton-based fed corresponded, respectively, to 75% and 25% of the total productivity of each production model. The tilapia growth performance indicates that the proposed production models are promising strategies for using natural food in a periphyton-based system and reusing effluents from monocultures, especially when inputting a high amount of nutrients as in P100–0.