Effects of dietary addition of synbiotic on the performance, carcass traits, and serum parameters of Japanese quails

This study aimed to evaluate the effects of different levels of synbiotic (Syn) on the growth performance, carcass traits, and serum parameters of Japanese quails. A total of 1,500 (750 male and 750 female) Japanese quails were assigned to five treatments, including the control (basal diet) and basal diets with the addition of 0.1, 0.2, 0.3, and 0.4% Syn according to a completely randomized design. Each treatment in the male and female experiment groups consisted of five replicates, with 30 chicks for each replicate. The addition of Syn had no effect on body weight (BW), while the BW of female quails was higher than that of male quails at day 42. The addition of Syn reduced feed intake (FI) and improved the feed conversion ratio (FCR) (P