Ffoulkes et al., 1978. Livest. Res. Rural Dev., 3 (2): 140-144

Four Zebu bulls of 200 kg live weight were used in a 4 x 4 latin square design to determine digestibility and voluntary intake of mixtures of chopped whole sugar cane and sweet potato forage in the proportions 100:0, 67:33, 33:67 and 0:100 (dry basis). The diets were recede isonitronenous with urea, and minerals were also given. There was an indication that voluntary intake of dry matter was lower on the sugar cane control than on the other diets containing sweet potato forage. Dry matter digestibility was in the-range 64 to 70% and did not differ between treatments. When the sugar cane control diet was compared with the treatment in which one third of the cane was replaced with sweet potato forage then the dry matter consumption index was significantly (P< .01) higher on the latter by 39% while intake of digestible DM was increased by 34%. The intake of sugar cane was reduced by only 9% when sweet potato forage was substituted at the one third level. It is proposed that the increase in voluntary intake caused by adding sweet potato forage to sugar cane may be due partly to the protein in the sweet potato forage acting as a by-pass nutrient and partly to improved rumen function due to the physical nature of this forage.