An evaluation of brewery waste as a replacement for concentrates in diets for growing crossbred common ducks

An experiment was carried out to determine the effect of feeding brewery waste that replaced different levels of concentrate in diets for growing crossbred common ducks. A total of 300 ducks at 3 weeks of age were allocated in a 2 x 5 factorial experiment. Two feeding systems were compared, with the brewery waste provided separately (S) or mixed (M) with a concentrate. For the first feeding system the concentrate was fed alone (C100M), or replaced successively by brewery waste at ratios of concentrate to brewery waste: 75:25 (C75M), 50:50 (C50M) and 25:75 (C25M) on a dry matter basis, and fed ad libitum. For the second system concentrate and brewery waste were fed separately, with the same levels as in the first system. Total feed intakes for both feeding systems and intakes of brewery waste, total dry matter, crude protein, calcium and phosphorus increased significantly as concentrate was reduced (p <0.05). Daily weight gains were not significantly different between the two feeding systems, but were significantly lower for the C25 and C0 diets (p <0.05). Replacement of 50% of the concentrate by brewery waste resulted in the best growth performance. The highest net profits were from the separate feeding system, and for ducks fed brewery waste only (C0). It is concluded that brewery waste can replace traditional diets for crossbred common ducks based on concentrate.