A PERSPECTIVE ON THE WET FAECES PRODUCED BY DRIED AND COARSELY GROUND OPUNTIA FICUS-INDICA CLADODES IN SHEEP DIETS -      H. O. de Waal, D. C. Zeeman & W. J. Combrinck

Department of Animal, Wildlife & Grassland Sciences, University of the Free State, Bloemfontein 9300, South Africa

Inclusion of cactus pear in ruminant diets is characterised by production of very wet faeces, often assumed to be diarrhoea. As partial substitution for coarsely ground lucerne hay, incremental levels (0, 12, 24 and 36%) of sun-dried and coarsely ground spineless cactus pear (Opuntia ficus-indica var. Algerian) cladodes were used in balanced diets for sheep. Feed intake and digestibility trials were conducted over a period of 19 days with 24 young Dorper wethers, divided in four treatment groups (T0, T12, T24 and T36). The four diets comprised respectively (on an air dry basis) 0, 120, 240 or 360 g/kg sun-dried and coarsely ground Opuntia cladodes; 660, 535, 410 or 285 g/kg coarsely ground lucerne hay; 300 g/kg yellow maize meal; 0, 5, 10 or 15 g/kg feed grade urea; and 40 g/kg molasses meal. The water intake of the wethers increased significantly (P<0.05) with increasing Opuntia cladode inclusions in diets, while urine excretion remained the same. The level of food intake and the faeces dry matter (DM) excreted remained the same for all diets, but the DM content of the faeces decreased with higher levels of Opuntia cladode inclusion. The wetter faeces produced by the sheep is ascribed to the mucilage content of the Opuntia cladodes. Although more definitive research is needed, it is concluded that the wet faeces produced by the sheep on diets T12, T24 and T36 was not as a result of diarrhoea induced by the coarsely ground Opuntia cladodes, but the larger quantities of water not reabsorbed from the lower digestive tract.