Automated Feeding in the Production of Brycon amazonicus as a Strategy to Increase Productivity and Feed Efficiency in Amazonian Aquaculture

Feed represents one of the main costs in aquaculture and has a strong influence on fish growth and production efficiency. Automatic feeders can optimize feeding management and improve feed utilization. This technology allows an increase in feeding frequency without increasing labor demand, while also promoting a more uniform feed distribution. This study evaluated the effects of feeding frequency and photoperiod extension on the productive performance of juvenile Brycon amazonicus reared in earthen ponds. In Experiment I, 1,920 juveniles with an average weight of ≈50 g were fed manually three times a day (M3X) and with the aid of automatic feeders three times a day (AF3X) and five times a day (AF5X). In Experiment II, 1,620 juveniles with an average weight of ≈300 g were fed manually five times a day under a 12-hour photoperiod (M12H) and under automated feeding systems with 12-hour (AF12H) and 18-hour (AF18H) photoperiods. Both experiments lasted 30 days. In Experiment I, fish from the AF5X treatment showed higher final weight (182.7 g), weight gain (126.1 g), specific growth rate (3.9% day⁻¹), and feed efficiency (88.2%), as well as a lower apparent feed conversion ratio (1.1) compared to other treatments (P < 0.05). A 100% weight uniformity was also observed in this group. In Experiment II, the AF18H treatment resulted in higher final weight (493.6 g), weight gain (188.9 g), SGR (1.6% day⁻¹), and feed efficiency (58.4%), as well as a lower feed conversion ratio (1.8) (P < 0.05). In both experiments, survival rate was 100% across all treatments. The results demonstrate that increasing feeding frequency and extending photoperiod using automatic feeders significantly improve performance of B. amazonicus, constituting a promising strategy to enhance productive efficiency in Amazonian aquaculture. In addition, the adoption of automated feeding systems may contribute to sustainability of aquaculture by improving feed utilization, reducing waste, and minimizing environmental impacts associated with nutrient release into aquatic ecosystems.