The use of walnut leaves (Juglans regia) as an antioxidant during the storage of mixed fodder for poultry

Abstract

Goal. To study the effect of walnut leaves (Juglans regia) on the oxidative stability of prepared poultry feed compared to a synthetic antioxidant agent and a control (without antioxidant). Methods. The object of research was three samples of complete ration combined feed for the parent herd of adult hens of the egg production direction: BR — basic ration without the addition of antioxidants; BRSA — a basic ration with the addition of a synthetic antioxidant; BRWL — basic ration with the addition of dry ground walnut leaves (2%). All samples were stored in the same conditions for 120 days. In the process of storage, indicators of oxidation status (acid and peroxide values of fat) and vitamin provision (content of vitamins A and E) were monitored. Results. In the process of storage, mixed fodder with synthetic (BRSA) and natural (BRWL) antioxidants had better indicators of oxidative stability compared to the sample that did not contain preservatives. Both samples of feed with antioxidants after 120 days of storage according to indicators of acid and peroxide numbers of fat remained within the normative limits, while in the base sample (BR) the acid number exceeded the critical value already on the 90th day of storage (30.96 mg KOH/g), and the peroxide number (0.35%J2) at the end of the experiment, which made this sample unsuitable for feeding poultry. The addition of walnut leaves and a synthetic antioxidant to the mixed fodder also contributed to better preservation of vitamins A and E and kept their content within the regulatory limits. The loss of vitamin A after 120 days of feed storage was 12% for BRSA and 34.4% for BRWL, and vitamin E was 8.2% and 15.5%, respectively. In contrast to this, the storage of vitamins in the basic compound feed was much worse: the content of vitamin A becomes below the extremely necessary norm after 90 days of storage, and vitamin E — after 60 days. Conclusions. The antioxidant and preservative properties of walnut leaves are confirmed. Adding it to mixed fodder for chickens during long-term storage inhibits the oxidative and hydrolytic processes of lipids and increases the preservation of vitamins. This makes walnut leaves a synthetic antioxidant alternative.