Effects of spatial distribution on the decomposition of sheep faeces in different vegetation types

The relative rate of sheep faeces breakdown was investigated in different vegetation types comprising Cichorium intybus, Lolium perenne, Lotus corniculatus and Trifolium repens across a range of plot sizes and at two spacing densities of faeces. Invertebrate populations were sampled using non-baited pitfall trapping. Relative breakdown rate was estimated using Perspex strips containing 10 holes filled with faecal material recorded daily until all holes were empty. Breakdown was most rapid in swards containing Lolium perenne and slowest in those containing Cichorium intybus. Faster rates of faecal breakdown were associated with higher numbers of invertebrates and when closely spaced but higher invertebrate numbers were observed in pitfall traps set at larger spacing intervals. When grazing and defecating sheep were included, the above results were reversed with faecal material breaking down significantly faster in C. intybus swards than in L. perenne. Vegetation type and stocking density potentially may be manipulated to regulate rates of faecal breakdown as part of an integrated parasite control strategy to be developed against intestinal parasites of sheep.