Spatial distribution on pasture of infective larvae of the gastro-intestinal nematode parasites of sheep.

Scottish Crop Research Institute, Invergowrie, Dundee DD2 5DA, Scotland, U.K.; AFRC Institute for Arable Crops Research, Rothamsted Experimental Station, Harpenden, Herts AL5 2JQ, U.K.
International Journal for Parasitology (Impact Factor: 3.64). 10/1989; 19(6):681-5. DOI: 10.1016/0020-7519(89)90047-7
Source: PubMed

ABSTRACT The horizontal distributions of infective larvae on pasture grazed by sheep have been investigated. Using Taylor's Power Law it was found that larvae had a more aggregated distribution in September than August, the Law index of aggregation being 1.97 and 1.89 for the 2 months, respectively. However, at each time the degree of aggregation remained fairly constant for a range of spacings between points from 5 to 30 m. These results suggest that Taylor's Power Law could be used as a basis for devising an efficient pasture sampling strategy. More data are required, however, to determine the extent to which aggregation of the larvae varies with time of the year.

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