Microdiet Formulation with Phospholipid Modulate Zebrafish Skeletal Development and Reproduction

Dietary phospholipids' (PLs) content, origin, and profile are known to affect fish development and reproductive performance, but their effects in zebrafish (Danio rerio) nutrition are still poorly investigated. Therefore, this study aimed to assess the effect of practical microdiets containing plant-based and marine PL sources in zebrafish growth, survival, skeletal development, and reproductive performance. Reproductive performance was evaluated according to sperm motility, number of eggs, egg morphometry, hatching rate, and offspring standard length at 5 days postfertilization (dpf). For this purpose, seven microdiets were used, where two control diets were tested along with a supplementation with soybean lecithin (SL) as a plant-based PL source, and krill oil (KO) and copepod oil (CO) as marine PL sources, or in combinations (SLCO and SLKO). KO supplementation decreased larval growth performance and induced severe skeletal anomalies. SL supplementation reduced sperm total motility but improved offspring length at 5 dpf. CO supplementation increased sperm motility and the number of spawned eggs. Our results showed that a careful selection of the origin of dietary PL sources for microdiet formulation is critical to ensure adequate skeletal development and reproductive success. This study contributes to the improvement of zebrafish microdiet formulation and optimization of zebrafish husbandry practices.