DIET COMPOSITION OF GUANACOS (LAMA-GUANICOE) AND SHEEP (OVIS-ARIES) GRAZING IN GRASSLAND COMMUNITIES TYPICAL OF UK UPLANDS

A study was undertaken to compare the diet composition of guanacos (La ma guanicoe) and sheep (Ovis aries) when pastured on improved and unim proved Agrostis spp./Festuca spp. dominated grassland typical of the U K uplands. Samples were collected from oesophageal fistulated guanacos and sheep grazing experimental plots that had been grazed previously by either sheep or guanacos. Sward composition and herbage biomass wer e determined for each plot using quadrat cuts. The sward composition a nd diet composition results obtained were used to calculate selectivit y indices for individual dietary components. Green leaf of broad-leave d grasses was the main dietary component for both animal species on bo th the improved and unimproved grasslands. In general, the guanacos co nsumed less green grass leaf and more dead grass leaf than the sheep. Their diets also contained significantly more Nardus stricta than shee p diets. The sheep diets contained significantly more Trifolium repens , which was consistently avoided by the guanacos. Only one dicotyledon ous species (Cirsium palustre) was consistently selected by the guanac os. There were fewer between-species differences in diet composition o n the previously sheep-grazed plots than on the previously guanaco-gra zed plots. (C) 1998 Elsevier Science B.V. Ail rights reserved.