Aquafeeds comprise one of the largest operational costs of the aquaculture sector. It is imperative to lower costs while formulating diets with high-quality ingredients which nutritional composition meet the requirements of the target species. If a target species is a novel one such as cobia (Rachycentron canadum), resources must be invested in investigating those nutritional requirements to optimize growth, health, and feed efficiency.
Protein and energy are two nutritional components that must be carefully considered when formulating diets as an imbalance of the two can have detrimental effects on the health of the fish and on overall production. Here we summarize the progress and results of a multi-factorial bio-energetic study on cobia of commercial sizes to estimate the requirements of protein/energy and amino acids. This information will be key to formulating more nutritionally precise diets tailored to the various commercial sizes.
Digestibility of nutrients and diets is another topic that must be evaluated when formulating diets. Most publications utilize fish that are significantly smaller than commercial size to carry out in-vivo digestibility. This can pose an issue due to the fact that as fish grow closer to their harvest size, their nutritional requirements will change and thus diet composition must also be altered. Here we summarize the progress and results of in-vivo- digestibility studies on cobia of different sizes to understand how fish size might affect digestibility.