The early stage in life is a crucial step in fish development and impacts fish quality during their whole lifespan. High-quality nutrition during the hatchery and nursery stage is part of the strategy to maximize fish performance. The ambition to improve aquaculture productivity up to harvest already starts in newly hatched fish.
Nutrition at the early stage impacts phenotypes during the entire lifespan. In addition, key developments of organs happen in early life (Fujimura and Okada, 2007). That’s why it is necessary to bring the right nutrients in sufficient amounts during this phase. Muscle also starts to be built early in life and nutrition favoring a good muscle structure will promote larger body weight at harvest (Kiesslingetal et al., 2006). Even if the period remains short in comparison to an entire life cycle, the importance of a high-quality nutrition should not be minimized as it is part of the strategy to prepare the future of the fish.
In order to demonstrate this statement, an experiment was conducted on tilapia for 236 days, starting from the first feeding. Only the feed used during the first month of feeding differed. One group was fed with a micro-extruded feed produced by marumerisation technology (Group 1) and the second group was fed a standard crumble feed (Group 2) during that period. The two groups were managed the same way and fed the same feed for the rest of the trial. A huge difference in live weight was observed after the first month since live weight was 3.17g and 0.52g (P<0.0001) in groups 1 and 2 respectively. The feed fed during the first month not only impacted performances during this period, but also performances up to harvest. Final live weight reached 797g and 683g (P<0.0001) and fillet yield was 37.1% and 34.5% (P<0.0001) in groups 1 and 2 respectively. Survival was also strongly impacted.
The benefit of premium micro-extruded feed on fish performances during the first month can be explained by nutrition, digestibility of the feed, feed stability in water and the pellet size adapted to fish mouth size while fish are growing. The benefit observed beyond, 7 months later, might come from a better development of the fish This experiment illustrates why investment in high quality-feeds at larvae and juvenile stages is part of the strategy to improve aquaculture productivity.