The Napier grass was established at the ISB mini-farm of the University of Malaya and fertilised with urea at a rate of 180 kg N/ha annually. The grass was harvested daily (at approximate 45–60 d maturity after the previous harvest) from four equal plots. Its maturity was controlled by cutting at different times to obtain similar quality grass throughout the experimental period. Each of the four plots was used for 15 consecutive days, and the re-growth from three of the previously used plots was used again at the end of the experiment. The grass was chopped mechanically to a length of 5–7 cm and fed to the animals when it was fresh. Soya waste was supplied by a supplier from a local soya bean-processing centre at 7-d intervals, stored in plastic containers, which were kept airtight. The commercial pelleted compound feed was purchased from a feed manufacturing company (FFM Marketing Sdn. Bhd., Selangor, Malaysia).