Citric acid (CA), also known as citric acid, with the molecular formula of C₆H₈O₇, is an important organic acid. It is colorless crystal, odorless, has a strong sour taste and is easily soluble in water. It is a natural preservative and food additive.

Adding citric acid to compound feed can disinfect, prevent mildew and prevent Salmonella from infecting animal feed. Animal intake of citric acid can reduce the proliferation of pathogens, inhibit the production of toxic metabolites and improve animal stress.
(1) Increase feed intake and promote nutrient digestion and absorption
Adding citric acid to the diet can improve the palatability of the diet. Citric acid can directly stimulate taste bud cells in the mouth, increase saliva secretion, play the role of flavoring agent, enhance animal appetite, improve animal food intake, promotes the digestion of nutrients.
(2) Promote intestinal flora health
Citric acid can reduce the pH in the gastrointestinal tract and obtain good growth conditions for probiotics such as lactic acid bacteria in the intestinal tract, so as to maintain the normal balance of microbial flora in the digestive tract of livestock and poultry.
(3) Enhance the body's anti stress and immune ability
Immunocompetent cells, namely T lymphocytes and B lymphocytes, play an immune surveillance role in the body. The results showed that feeding citric acid to broilers could make the density of immune active cells higher, make the chickens in a better immune state, inhibit the reproduction of intestinal pathogens and prevent the occurrence of infectious diseases.
(4) As mildew inhibitor and antioxidant
Citric acid is a natural preservative. Citric acid can reduce the pH of feed, inhibit the proliferation of harmful microorganisms and the production of toxins, and has obvious anti mildew effect. As a synergist of antioxidants, the mixed use of citric acid and antioxidants can improve the antioxidant effect, prevent or delay feed oxidation, improve the stability of compound feed and prolong the storage period.