Ontogenetic changes in food consumption and performance of pacu (<i>Piaractus mesopotamicus</i>) post-larvae and two hybrids in a semi-intensive system

This study evaluated ontogenic changes in food consumption and post-larval growth of pacu (<i>Piaractus mesopotamicus</i>) and the hybrids patinga (<i>P. mesopotamicus x P. brachypomus</i>) and tambacu (<i>Colossoma macropomum</i> x <i>P. mesopotamicus</i>) in a semi-intensive system with daily offer commercial feed and fertilized water to promote plankton growth. In the first week, all groups mainly consumed resting eggs of Cladocera (epiphytic), gradually diversifying their diet. Pacu primarily consumed immature bryozoans, patinga ingested Chironomidae larvae, and tambacu fed on Cladocera and Copepoda. Tambacu showed significantly greater growth in standard length and weight compared to pacu and patinga (<i>p</i> &lt; .01); however, further studies on zootechnical and environmental aspects are needed. This is the first study to investigate the feeding of post-larvae of round fish and their hybrids. The results indicate a preference for natural foods, highlighting the need for future research to develop feeding protocols with a greater share of natural foods.