Factors regulating tapeworm populations: dispersion of eggs of Taenia hydatigena on pasture.

A dog with four patent Taenia hydatigena was placed at a fixed site on a pasture for 50 days. The spread of the eggs was determined by grazing lambs for 10 days on various plots, and counting the cysts present at autopsy. Some 'wild' eggs were detected on the pasture before the dog was introduced. Nevertheless, a marked divergence from randomness was detected in the cyst counts of lambs grazed within 80 metres of the kennel but not beyond from 10-20 and 40-50 days after the dog had been introduced. The main egg clusters remained within a radius of 25 metres.