Time of Application of Anthelmintic to Cattle Infected with Fasciola hepatica

Abstract

In the suburbs of Kobe 105 dairy cows were subjected to fecal examination ten times. Cows from which eggs of Fasciola hepatica had been detected were given an anthelmintic against adult worms seven times. The mean rate of egg detection was 52.2% after the first treatment and 31.2% after the last one, showing a gradual decrease.
Fasciola infection was presumed to take place mostly by ingestion of metacercariae attached to rice straw. It was concluded that anthelmintic should be used mainly over a period from January to May in the Kobe area, and that each cow should be treated at least three times, or in October, January, and April or May.