Effects of Micellar Quercetin Supplementation on Growth Performance, Nutrient Digestibility, Fecal Microbiota, Meat Quality, and Physiological Status in Broiler Chickens.

This study investigated the impacts of micellar quercetin (MQ) supplementation on growth performance, meat stability, excreta gas emissions, and physiological status. During a 35-day trial, 640 Ross 308 broilers were utilized. These birds were one day old, with an average initial body weight of 43.34 ± 1.43 g. They were randomly distributed across four experimental diets, each consisting of 10 replicate pens with 16 chicks per pen. The diets included the following: control (CON) with 0% micellar quercetin (MQ), TRT1 with 0.025% MQ, TRT2 with 0.050% MQ, and TRT3 with 0.100% MQ. The results indicate that broilers fed diets with increasing levels of MQ exhibited significantly higher body weight gains (BWGs) compared to the control group ( < 0.05). There was a clear linear increase in the breast muscle percentage with higher levels of quercetin supplementation ( < 0.05), while the breast color remained consistent across all groups ( > 0.05). Both cooking loss and drip loss exhibited a linear decrease as MQ levels in the diet increased ( < 0.05). The level of aspartate aminotransferase (AST) tended to decrease with higher MQ levels. Thyroxine (T4) and lymphocyte levels also showed a linear increase with increasing MQ dosage in the diet ( < 0.05). However, no significant effects were observed on nutrient digestibility, gas emissions, or fecal microbial components (, , and ) with higher levels of MQ supplementation ( > 0.05). In conclusion, augmenting quercetin levels in the diet positively influenced the BWG, breast muscle development, and meat quality parameters such as cooking loss and drip loss, with beneficial effects on blood profiles.