There are many nutrients that affect animal health and strengthen immunity. Some of these are recognized as additives. Ascorbic acid has a very important function in the immune system, in the synthesis of carnitine and in the use and absorption of other nutrients. β -glucan is a stimulator of the cardiovascular system and immune system. β -glucan has a stimulating effect on macrophages, increasing the cytotoxicity and phagocytic capacity of macrophages. It also shows antioxidant, antiviral, antibacterial, and antifungal activity and has a healing effect on wounds. Inulin is a prebiotic that is isolated from the roots of chicory and yams and is effective on the immune system. It has been determined that prebiotics, which are very difficult to digest under normal conditions, are the food of probiotics. Probiotics affect the immune system with the metabolites they secrete. Another important nutrient for immunity is amino acids. Having sufficient amino acids has a positive effect on immunity. When the minerals required in chemical reactions are at a sufficient level, they have an immune enhancing effect. Studies are carried out on the effects of boron mineral, which has rich deposits in our country, as an additive in animal feeds.