CASSAVA FORAGE AS A CATTLE FEED: APPARENT DIGESTIBILITY AND CONSUMPTION OF THE WHOLE FORAGE

Four Zebu bulls of about 200 kg liveweight and two years of age were used to measure the digestibility of cassava forage (leaves, petiole and green stem). One animal selected leaves and petiole, while the other three ate the entire forage. The average digestibility (mean of three ± SEx) was 66.5 ± 0.6 % with a Consumption Index of 2.00 ± 0.16 kg/100 kg liveweight. These values compare favourably with measurements made with sweet potato and banana forage. Key Words: Cattle, cassava forage, digestibility, intake A number of experiments have recently been carried out using the aerial part of cassava as a component of the diet to supply fibre and protein (Meyreles et al 1977a; Meyreles et al 1977b; Meyreles et al 1977c; Fernandez et al 1977; Fernandez et al 1978). It has generally been found that small additions of cassava forage to cane diets have been associated with only slight improvement in animal performance. However, when given as a forage source in molasses based diets, the rate of animal liveweight gain has been high. It is therefore important to know the apparent digestibility of the forage alone in order to have a better understanding of the way it functions as a dietary component. Materials and Methods Animals, Treatments and Design: Four Zebu bulls of approximately 200 kg were given chopped cassava forage (green stem, petiole and leaves). All four animals were on experiment at the same time. Procedure: The animals were given the chopped cassava forage for one week before being put into digestibility crates for a second week. A total collection of faeces was made during the last six days of this second week. Food consumption was recorded daily, faeces were bulked in a plastic bin until the end of the collection period when they were weighed, mixed and dry matter determined. The cassava forage was offered ad libitum, fresh forage being offered daily in the morning after removal of the surplus from the previous day. At all times the animals had access to water and were given a mineral supplement of 60 g/d of salt and dicalcium phosphate (50:50 w/w)