Effect of krill meal on the reproductive performance of broodstock Nile tilapia

Abstract

This 12-week study evaluated the impact of krill meal (KM) in Nile tilapia, Oreochromis niloticus, reproductive performance. Two test feeds with 2% and 5% KM were compared to a commercial tilapia broodstock feed. Fish were stocked in 12 hapas with 50 females and 16 males each, allowing four replicate hapas per dietary treatment. Egg production exhibited a general decline. The control group yielded 16,066 ± 6,124 eggs per hapa, while the 2% KM diet showed an 18% increase (18,976 ± 6,417 eggs), and the 5% KM diet exhibited a 30% increase (20,947 ± 7,029 eggs). However, no statistically significant differences were observed in egg production. Spawning females declined over time, with 5% KM showing a 29% increase, but no statistical differences could be detected among dietary treatments. Egg hatching rates remained consistent, but the 5% KM diet hinted at a positive trend with 10% more larvae at day 10 despite the lack of statistical differences. Females fed KM spawned more frequently, and the 5% KM diet influenced higher fat content and elevated levels of omega-3 in Nile tilapia eggs. Overall, the study suggests positive effects on reproductive performance and larval survival in Nile tilapia with inclusion of krill meal in their diets.