Disophenol in bovine gastrointestinal and lung nematodes

Abstract

The effect of the use of Disophenol applied every two months was studied in 48 weaned, crossbred (Zebu x Holstein) calves, six to nine-month old, naturally infested by gastrointestinal and lung nematodes. The animals were subdivided at random into four groups of twelve (A, B, C & D), and were maintained in four paddocks of approximately 8,300 m². Groups B and D were treated with Disophenol at 10 mg/kg. live weight, groups A and C remained untreated, while a horse was added to groups C and D for the purpose of other studies. Weekly fecal examination and two monthly necropsies were carried out for each group between May and October 1977. The statistical design utilized was complete randomization. Disophenol significantly reduced (P≤0,05) the number of Haemonchus placei, Oesophagostomum radiatum, and Bunostomum phlebotomum adults, did not have a marked effect on fourth final stage larvae and had no effect on fourth initial stage larvae of Haemonchus placei. It also had no effect on either adults or immature forms of Trichostrongylus axei, Ostertagia ostertagi, Ostertagia lyrata, Cooperia punctata, Cooperia pectinata, Strongyloides papillosus and Dictyocaulus viviparus.