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The study was conducted in the production conditions of the State Research Station of Poultry Breeding of Livestock Farming Institute of the NAAS (village Birki, Kharkiv region) on the parent flock of Birkivska barvysta chickens. The effectiveness of using 1% crushed walnut leaves (Juglans regia) as a phytogenic feed additive in the composition of compound feed was studied. During the six months of the experiment, it was found that the use of the phytoadditive contributed to a reduction in the age of the beginning of egg laying, more stable dynamics of egg production, increased egg production intensity, hatching egg yield and bird survival, which indicates a strengthening of the physiological state of the bird and a decrease in the impact of stress factors. Experimental hens that consumed walnut leaves began egg laying five days earlier, and their average egg production during the period increased by 6.8%. Under the influence of biologically active substances of the leaves (phenolic compounds, flavonoids, juglone), an improvement in the quality of incubation products was observed – the yield of incubation eggs increased from 65.1 to 69.0%, while the weight of eggs remained stable, which indicates a balanced use of nutrients without overloading the body. A decrease in feed consumption per 10 eggs by 6.7% confirmed an improvement in feed conversion, which is explained by the positive effect of the phytoadditive on digestion and metabolic balance. The survival rate of the livestock in the experimental group reached 98.9%, which is 2.9% higher than in the control, and indicates the immunomodulatory properties of the additive. Economic calculations confirmed the feasibility of using walnut leaves as a phytogenic additive in the diet of chickens. An increase in profit from the sale of eggs by 18.4% and a decrease in the cost of one incubation egg from 7.32 to 6.43 UAH were recorded, which provided an additional effect of 14.05 thousand UAH for the experimental period. At the same time, the use of self-prepared raw materials made the technology more profitable, but even if raw materials were purchased from suppliers, the use of leaves remained economically justified with an efficiency of 4.47 thousand UAH relative to the control. The results obtained indicate that walnut leaves can be used as an affordable, environmentally safe and effective phytogenic supplement in the diets of parent flock chickens as an alternative to synthetic antioxidants. This approach contributes to increasing the productivity and viability of poultry, improving product quality and improving economic indicators, which makes the technology suitable for implementation in organic poultry farming systems.

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