In animal production, there is an increasing emphasis not only on the efficiency of feed in terms of growth performance and production, but also on its impact on the health and overall well-being of farmed animals. “This approach is particularly important in aquaculture, where fish health directly affects both the productivity of the farm and its economic and environmental sustainability. Therefore, optimizing feed rations through the targeted use of additives is an important tool for improving immunity, supporting a healthy intestinal microbiome, reducing stress, and preventing disease, which can, among other things, reduce the use of antibiotics and other substances,” explained Lucie Všetičková from the Department of Fisheries and Hydrobiology at MENDELU.

“To optimize fish health and growth, it is generally necessary to provide sufficient high-quality protein and an optimal amount of energy in the form of easily digestible carbohydrates or suitable fats, a favorable composition of amino acids and fatty acids, sufficient vitamins and minerals, and appropriate additives,” the scientist outlined. Feed additives include natural immunostimulants, probiotics, prebiotics, and micronutrients.

For example, prebiotics stimulate beneficial intestinal microflora, improve digestibility and nutrient absorption, and strengthen the immune system thanks to improved intestinal wall integrity and activation of defense cells. Micronutrients are vitamins and minerals that provide antioxidant protection, support immunity, and improve growth. “The advantage of additives that boost immunity in fish lies mainly in the fact that they support the body’s defenses, thus bringing certain benefits to both the breeder and the animal. They increase their resistance to adverse environmental conditions, stress, or the occurrence and effects of various pathogens. Simply put, they improve the health, performance, and sustainability of breeding,” said Všetičková.

In terms of ecological footprint, the main burden is the production and consumption of feed and the associated emissions and pollution. “Unfortunately, Europe is not self-sufficient in the production of protein components for feed. Fish meal is most often imported from South America, and its production is neither sufficient nor sustainable, and the price is high. Therefore, it is most often replaced by soybean meal, which we also import, because the largest producer of soybeans is the United States. To reduce the potential burden on the recipient, the phosphorus content in feed is limited and its digestibility is monitored, as is the content of proteins and nitrogenous substances,” explained the scientist. In recirculating aquaculture systems, biofilters and the subsequent use of sediments and sludge separated from the breeding systems ensure that the impact is minimized.

A workshop held in September at the Department of Fisheries and Hydrobiology focused on the use of new additives in fish nutrition, with the aim of familiarizing the general public with these topics. The workshop was organized with state support from the Technology Agency of the Czech Republic as part of the National Competence Center Program within the project Influencing the health, production parameters, and internal environment of farm animals and fish with selected feed additives.