Functional diets are an emerging and promising strategy to address pathogen challenges in aquaculture. These diets are formulated not only to meet the basic nutritional needs of fish but also to enhance their overall health and disease resistance. The formulation of nutritionally precise diets for Nile tilapia is essential to ensure optimal growth, health, and overall productivity of this species. Given the specific nutritional requirements of Nile tilapia, diets must be carefully tailored to provide the right balance of nutrients. Moreover, these diets should be adjusted to the varying environmental conditions in which tilapia are raised, such as water temperature, quality, and presence of stressors. Aquaculture producers need to work together with feed manufacturers to ensure the constant use of high-quality diets. The objective of this presentation is to showcase the different tools that the University of Miami Aquaculture Program has been using to be able to rapidly and cost-effectively assess additives, ingredients, and diets to allow the industry to improve its production and efficiency through high-quality diets. Among the various available tools, special attention has been placed on in-vivo digestibility and cell lines.
Selecting high-quality additives and ingredients for target species and feed manufacturing conditions is crucial for diet quality and its impact on animal health and production. Evaluating diet quality and generating farm results is challenging, as the effects of a low-quality diet are delayed and compounded, potentially causing serious economic impacts. Thus, the industry must develop and adopt tools to rapidly and cost-effectively monitor and evaluate additives, ingredients, and diets. An in-vivo digestibility trial with harvest-size finfish tested if a modified Acid-Insoluble Ash (AIA) protocol could determine Apparent Digestibility Coefficients compared to traditional yttrium oxide, a complicated external marker not fully adopted due to its logistical complexity. Results showed no significant difference between the markers, though AIA slightly underestimated by 2.32% ± 0.71. Another developed tool uses immortalized fish cell lines to evaluate additives, ingredients, and diets. This research aims to rapidly and cost-effectively determine the cellular impacts of proliferation, toxicity thresholds, and antioxidant capabilities of different feed components. For example, the antioxidant effect of grape extract additive on salmonid cell lines shows clear cellular protection when an oxidative agent is added at varying concentrations.