Sheep production on the north coast of New South Wales. 1. Effect of anthelmintics and grazing management on production and helminthosis of Merino wethers

Abstract

Merino wethers grazing unfertilized pastures in rotational and continuous grazing systems on the North Coast of New South Wales were drenched at high, medium and low frequencies. Liveweights, wool production, faecal nemarode egg counts of the sheep and deaths from helminthosis were recorded. The results indicate that high stocking rates and good wool production can be maintained with frequent drenching. Haemonchus sp. and Trichostrongyh sp. were the most important nematodes that infected the sheep and the epidemiology and control of these two parasites is discussed.