Cow/Calf Parasitology

How Critical is the Time of Deworming? and, Ostertagiosis Update

Abstract

Gastrointestinal parasitism is a year round problem in beef cattle herds. In attempting to formulate a strategic parasite control, we looked for the one parasite species, Ostertagia ostertagi, which caused most of the parasite problems causing clinical disease and economic loss. So based upon its seasonality and the peculiarities of its life cycle, a strategic deworming program including pasture management was developed. Perhaps the most important has been a better understanding of the epidemiology of ostertagiosis in each of our geographical-climatic regions. This has permitted development of control (pasture rotation) and treatment schedules which effectively reduce the impact of this parasitism.