The impact of dietary supplementation of different feed additives on performances of broiler breeders characterized by different egg-laying rate

ABSTRACT This study was conducted to determine the impact of different feed additives on reproductive performance, egg quality, intestinal morphology, and blood metabolic profile of broiler breeder with different egg-laying rate. A total of 512 AA broiler breeders (48 wk old) were used in a 2 × 4 factorial design which encompassed 2 egg-laying rate levels [average (AR) and low (LR)] and 4 different dietary groups [control (no additive), 6×108 CFU/kg Enterococcus faecium (EF), 200mg/kg apple pectic oligosaccharide (APO), and 1,000mg/kg tributyrin (TRI)]. As expected, the LR breeders presented higher egg weight, eggshell thickness (P