Fishmeal (FM) is the primary protein source in aquaculture feeds, but its price has risen due to overfishing and climate change reducing supply. Alternatives like plant-based proteins, insect meals, and single-cell proteins are being explored, but their lower digestibility can hinder growth and feed efficiency. Enhancing their digestibility is key to meeting the nutritional needs of farmed species.
Economix is a plant-based feed additive produced by TECHNA ( Couëron, France) that aims at enhancing protein digestibility . It offers a promising solution for reducing FM use and substituting it with more affordable plant proteins.
A digestibility trial was held at Sparos, Portugal, to evaluate the effect of Economix on apparent digestibility coefficients (ADC) of nutrients in European seabass (Dicentrarchus labrax ). The trial comprised two experimental diets, both containing 0.02% yttrium oxide as an inert digestibility marker.
The Economix diet reduces F M by 2% compared to the Control diet, replacing it with plant proteins (soybean meal, wheat) and 0.2% Economix additive. This reformulation achieves a cost reduction of -1.78% compared to the Control diet.
Each diet was tested in triplicate groups of 13 fish (mean body weight: 73 ± 5 g), maintained in 60 L tanks at a constant water temperature of 20.0 ± 0.43°C. Feces were collected in tanks equipped with a fecal decantation column (Guelph system).
The results showed that the inclusion of 0.2% Economix significantly improved the amino acids digestibility of 13 out of the 17 analyzed amino acids, including lysine, methionine, and threonine (p < 0.05). This trial also indicated numerically higher values, although not statistically significant, for protein, fat and energy digestibility.
To conclude, Economix, with its ability to enhance amino acid digestibility, offers a viable solution by enabling the reduction of fishmeal and the incorporation of cheaper, more sustainable protein sources , while maintaining optimal performance in fish and shrimp.