The effect of the dung beetle, Onthophagus gazella, on the ecology of the infective larvae of gastrointestinal nematodes of cattle

The ecology of nematode larvae infective for cattle was studied in the vicinity of standardized dung pats experimentally exposed lo the dung beetle, Onthophagus gazella. In moist climatic conditions two, 10 and 30 pairs of O . Gazella reduced the numbers of larvae on grass surrounding dung pats by 40, 74 and 66% respectively, compared with control pats not exposed to beetles. After 84 days, many larvae remained in control pats and pats attacked by two pairs of beetles, but few were found in other pat types. Infective larvae survived for at least 84 days in soil and buried faecal material, and larval migration through soil occurred. The daily temperature variation within dung beetle burrows was considerably less than that of the external environment. This insulation against extremes of temperature probably contributed to the longevity of buried larvae.