Supplementation of Mannan Oligosaccharide in Broiler Diets on Growth Performance and Nutrient Digestibility

This study evaluated the effects of mannan oligosaccharide (MOS) supplementation in broiler diets on growth performance and nutrient digestibility. A total of 200 vaccinated, day-old, broiler chicks were randomly assigned to five dietary treatments with four replicates each following a completely randomised design. The experimental diets included a control with no MOS supplementation (T1) and four treatment groups supplemented with MOS levels of 0.5 (T2), 1.0 (T3), 1.5 (T4) and 2.0 (T5) g kg^-1 diet. Growth performances, dressing percentage, carcass quality, nutrient digestibility of feed and cost-benefit were evaluated. Results indicated that live weight of birds at 21 d of age was significantly higher (p<0.05) in T4 (1,220±88 g) and T5 (1,220±88 g) compared to T1, T2 and T3. However, there were no significant differences in feed conversion ratio, carcass weight and dressing percentage among the treatment groups (p˃0.05). Additionally, the water holding capacity of meat was significantly higher (p<0.05) in T3 and T4 (78±17%) groups compared to T1 (72±17%). During the starter period, dry matter (77.2±1.6%) and crude fat (90.2±2.4%) digestibility were significantly higher in T4 compared to the control. However, no significant differences were observed during the finisher period. Crude fiber digestibility during both starter and finisher periods was significantly higher in birds fed with T4 (74.6±1.3% and 70.6±1.9%, respectively) compared to the control. Profit per bird was significantly higher (p<0.05) in T4 (LKR 1,157±52) compared to T1 (LKR 616±52). In conclusion, supplementation of MOS at 1.5 g kg-1 enhances the net profit while improving growt