Influence of Hawthorn (Crataegus tanacetifolia) Fruit Vinegar Supplementation on Meat Quality and Gut MicrobiotainHeat-StressedBroilers; [Alıç (Crataegus tanacetifolia) Meyve Sirkesi Takviyesinin Isı Stresi Altındaki Etlik Piliçlerde Et Kalitesi ve Bağırsak Mikrobiyotası Üzerindeki Etkisi]

This study investigated the influence of the consumption of hawthorn (Crataegus tanacetifolia) fruit vinegar (HFV), a fermented product, on meat quality and gut microbiota in broiler chickens under cyclic heat stress (HS). A total of 300 one-day-old male Ross 308 chicks were divided into six groups with five replicates of ten birds, following a 2×3 factorial design with two temperatures (24 and 35°C) and three HFV supplementing levels (0, 2, and 4 mL/L) after one-week acclimation. Broilers in the thermoneutral groups were kept at 24°C, while HS groups experienced 35°C for 8 hours daily from day 21. Feed and water were provided ad libitum under a 24-hour lighting program. HS increased breast pH, reduced b* color value, raised ΣSFA and ΣMUFA levels, and lowered ΣUFA and ΣPUFA ratios. Supplementing 4 mL/L HFV increased breast L* color value and ΣSFA level while reducing ΣUFA ratio. The 2 mL/L HFV dose decreased ΣMUFA and increased ΣPUFA levels. Overall, HFV supplementation improved meat quality and beneficially altered fatty acid composition in heat-stressed broiler breasts. These results suggest that HFV supplementation may be a practical natural additive for broilers under cyclic heat stress and provide new evidence regarding its combined effects on meat quality and intestinal microbiota. Content of this journal is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.