Immunomodulatory feed additives for farm animals and fish

Abstract

Background.  Modern applied biotechnology is focused on the development and implementation of fundamentally new multifunctional feed additives in a complex form. Currently, new approaches to the maintenance of farm animals and aquaculture objects under the influence of environmental factors are being sought, based on the use of biologically active additives. Intensive antibiotic therapy has become one of the reasons for the disruption of normal bacteriocenosis and a decrease in the immunobiological reactivity of animals and fish, the emergence of resistant strains of pathogens, which reduces the therapeutic effect of antibacterial drugs. The use of antibiotics leads to the accumulation of microorganisms with complex antibiotic resistance in the environment, their entry into natural water bodies is almost impossible. One of the promising ways to solve these problems is the use of feed additives with immunomodulatory action. The article examines existing feed additives with biological activity, provides generalized literature data on the use of biological additives in animal husbandry and aquaculture.

Purpose. The objective of the present study is to investigate impact of immunomodulatory feed additives on farm animals and fish.

Materials and methods. Feeds play a crucial role in the diet of farm animals and fish, as they must contain all the necessary nutrients, vitamins and minerals to ensure healthy growth and development of animals and aquaculture objects. Such preparations as probiotics (including symbiotics and metabiotics), prebiotics, and synbiotics, which are actively used in feed production, meet these requirements. In 1995, Gibson and Robertfroy introduced the concepts that should be classified as prebiotics and found that these components should be: 1) a selective component that promotes the metabolic activity or growth of one or more beneficial bacteria; 2) capable of altering the microbiota towards a healthy state; 3) capable of exerting a systemic or luminal beneficial effect on the host organism; 4) not absorbed and not hydrolyzed in the upper part of the stomach.

Results. Current research shows the positive impact of prebiotic use on performance, including improved weight gain, improved feed conversion and reduced disease. Prebiotics promote the growth of beneficial microorganisms such as bifidobacteria and lactobacilli in the intestines of animals. This reduces the concentration of pathogens such as salmonella and coliform bacteria, which reduces the risk of disease and improves the overall health of animals and fish. Research confirms the possibility of reducing the use of antibiotics in feed through the use of prebiotics, which is important in the context of the problem of antibiotic resistance. Prebiotics can be used to improve the environmental sustainability of livestock and aquaculture, as they help to reduce the release of harmful substances into the environment.

Conclusion. Numerous scientific studies confirm the beneficial effects of immunomodulatory additives on the health of animals, poultry and aquaculture objects, especially in terms of protection against pathogens, stimulation of the immune response and increased productivity. Prebiotics can be used as an alternative or enhance the effect of probiotics. The use of a combination of these components, demonstrating a synergistic effect, can be even more effective in stimulating the intestinal microbiota and protecting animal health. One promising area of research is the use of wheat grain heap as an immunomodulatory additive, which has high prebiotic properties. In the future, it is necessary to pay attention to studies of the thermal treatment of grain in the production of feed and feed additives. It should be emphasized that the use of feed additives such as probiotics, prebiotics and synbiotics is safe, does not have a negative impact on the natural environment and reduces the demand for antibiotic-based growth promoters. However, the mechanisms of action of probiotic organisms, prebiotics, and their combinations in synbiotics require further research. In the technology of compound feed production, plant raw materials, including wheat, are subjected to the extrusion process in order to increase the nutritional value, during which, during heat treatment, pathogenic microorganisms are killed. Presumably, wheat grain of early ripeness phases may lose its beneficial properties during heat treatment (extrusion). In this regard, it is advisable to conduct research on the effect of grain processing on its prebiotic properties.

Sponsorship information. The work is carried out as part of the project “Development of personalized feeds of a new generation with plant and probiotic additives to increase the survival rate and improve the health of fish” (FZNE-2023-0003).

EDN: DHCYQT