Performances zootechniques du Sigan Cordonnier (Siganus sutor) soumis à deux régimes alimentaires : provende industrielle d’AGRIVAL et provende expérimentale à base de laisse de mer en milieu contrôlé à Toliara.

Abstract

Fish farm plays an increasingly important role in the production of animal proteins,
providing a solution to the global demand for seafood products while contributing to food
security. However, reliance on industrial feeds, which are often costly and imported, poses a
significant challenge. In this context, exploring local resources like sea wrack for the
formulation of alternative feeds presents a promising opportunity. Sea wrack, an accumulation
of organic marine debris (algae and seagrass) washed up on beaches, is an abundant resource
along the coasts of Madagascar. This study, conducted over a period of 4 months (April-August
2024) at the Belaza marine station, evaluates the use of sea wrack as an ingredient in the diet
of Siganus sutor, a prized reef fish in Madagascar. The objective is to compare growth, survival,
and feed conversion between an industrial feed (P1) and an artisanal feed based on sea wrack
(P2). The results show that fish fed with P1 achieve an average final weight of 94.75 g ± 11.29,
significantly higher (ANOVA, p < 0.005) than those fed with P2, which have an average final
weight of 41.3 g ± 9.17. However, survival rates are higher with P2, reaching 83.8% (ANOVA,
p = 0.005) compared to 71.5% for P1. These results suggest that while P2 limits growth, it
promotes fish survival. The study concludes that sea wrack could play a key role in sustainable
and affordable aquaculture in Madagascar.