Feeding dihydroquercetin to broiler chickens.

1. A total of 80 male Ross 308 broilers were used in a study to investigate the effect of dietary dihydroquercetin (DHQ) on growth performance variables, gastrointestinal tract (GIT) and immune organ development, glutathione peroxidase (GPx) and haemoglobin in blood, hepatic vitamin E content, dietary N-corrected metabolisable energy (AMEn), and nutrient retention coefficients when fed to broiler chickens from 7 to 35 days of age. 2. Two treatments were used in this study: control (C) and C + 0.5 g/kg extract of Siberian Larch (Larix sibirica) per kg feed, containing 85 % DHQ. The diets were fed over two feeding phases, a grower phase from 7 to 28 d of age, and a finisher phase from 28 to 35 d of age. The birds were reared under the breeder's recommended conditions. 3. In general, there were no effects of DHQ on growth performance of broiler chickens. However, the results of this experiment showed that there can be changes in redness colour of the breast meat when DQH is fed. No negative effects of feeding DHQ at 0.5 g/kg diet were observed in this study. 4. Supplementation of poultry diets with DHQ under standard industry rearing conditions, did not improve performance or any of the studied variables, except an increase of redness index of the breast fillets. Feeding DHQ at different doses and/or under more challenging conditions, e.g. heat stress, may, however, bring positive responses.