The effects of probiotic Yeasture® using at different rearing periods on performance, intestinal microbial population and carcass traits in broiler chickens

The present study was conducted to investigate the effects of using probiotic Yeasture® at different rearing periods on performance, intestinal microbial population and carcass traits in broiler chickens. A total of 378 one day old chickens (male and female) were randomly allotted to one of the 21 floor pens in a completely randomized design with seven treatments and three replicate groups and eighteen chickens in each group (9 male and 9 female). The Experiment treatments consisted of seven groups: A (control, without probiotic), B (prebiotics feeding between 1 to 10 days), C (prebiotics feeding between 1 to 24 days), D (prebiotics feeding between 1 to 42 days), E (prebiotics feeding between 11 to 24 days), F (prebiotics feeding between 11 to 42 days) and G (prebiotics feeding between 24 to 42 days). The chickens received the desired probiotic at different days of rearing period. The basal diets were corn and soybean meal, so 0.3 g/kg of basal diets in starter (1-10 days), 0.25 g/kg of basal diets in grower (11-24 d) and 0.2 g/kg of basal diets in finisher (24-42 d) period of probiotic was added to the basal diets for each other than treatment. The growth performance (evaluated through body weight gain, feed intake and feed conversion ratio), intestinal microbial population (the measurement of Lactobacillus and Coliforms) and carcass traits (relative weights of carcass, intestine, liver, gizzard and abdominal fat) were determined. Body weight gains and feed conversion ratio were significantly improved in broilers with added probiotic compared to the control group (P<0.05) whereas feed intake was not significantly altered. In addition, intestinal microbial population and carcass and gizzard weights markedly increased in the probiotic treated birds compared to control chickens (P<0.05). These results show that diet supplementation with probiotic Yeasture® at the early days of the rearing periods of broiler chickens especially, 1 to 24 and 1 to 42 days, had a positive effect on intestinal microbial population, leading to more nutrients being assimilated by the chickens and consequently greater performance in broiler chickens.