Effects of β-glucan and Bacillus subtilis on growth performance, blood profiles, relative organ weight and meat quality in broilers fed maize–soybean meal based diets

Abstract

This study was conducted to determine effects of dietary supplementation of β-glucan and Bacillus subtilis on growth performance, blood profiles, relative organ weight, and meat quality in broilers fed maize–soybean meal based diets. A total of 480 mixed sex broilers (BW of 46.3±0.5g) were randomly assigned to 1 of 4 treatments in a 2×2 factorial arrangement with 2 levels of β-glucan (0 or 1g/kg) and Bacillus subtilis (0 or 108cfu/kg). There were 6 replicate pens/treatment with 20 chicks/pen for growth performance and 5 chicks/pen for meat quality and blood profiles in this 5-wk study. Broilers fed Bacillus subtilis diets had 5.3% and 3.3% greater (P<0.05) body weight gain (BWG) during d 22–35 and throughout the study, respectively. No effects were observed in blood profiles. Administration of either β-glucan or Bacillus subtilis increased (P<0.05) 3.9% or 3.8% of the relative weight of spleen, respectively, while the supplementation of β-glucan decreased (P<0.05) the relative weight of abdominal fat by 16.0%. Dietary supplementation with β-glucan decreased the breast meat b⁎ value 26.2% (P<0.05), and a synergistic interactive effect of β-glucan and Bacillus subtilis was observed (P<0.05) in b* value of breast meat. In conclusion, Bacillus subtilis at 108cfu/kg of diet improved BWG and relative weight of spleen, while 1g/kg β-glucan did not improve BWG but decreased the relative weight of abdominal fat and b* value of breast meat in broilers.