Observations on infestations of undipped cattle of British breeds with the cattle tick, Boophilus microplus (Canestrini).

Abstract

A small herd of cattle infested with the cattle tick, Boophilus microplus (Canestrini) was kept in a previously unstocked paddock for 11 months without treatment for tick infestation. Frequent examinations showed that widely differing numbers of ticks developed on the cattle. The "tick resistance" of one animal, which showed no adult ticks during the summer months, could only be accounted for by mortality of the larvae and nymphs on the animal, since as many larvae were seen on selected small areas of this animal as on some animals carrying many adult ticks. The animals grazed together and thus would encounter similar numbers of tick larvae. The degree of susceptibility to adult tick infestation showed negligible correlation with skin thickness measurements and was not related to coat length. Larvae reappeared on the cattle 6 weeks after the first stocking of the paddock in March. The animals became almost free of ticks for 2 weeks in August. Although larvae were most numerous in November-December, they gave rise to fewer adults than the earlier wave of larvae in September- October. Some of the cattle suffered from "tick-worry'' in October, but thereafter their condition improved without treatment.

The use of sampling methods in studies of the distribution of larvae of Boophilus microplus on pastures.

“…The decline in numbers of larvae on all areas between mid November and the end of December is associated with the end of the second summer generation of ticks (Wilkinson 1955). There was fair agreement between catches of larvae during pasture sampling, and counts on selected areas of the flanks and dewlaps of cattle (Fig.…”

“…In March 1952, six spayed cows were admitted to the hitherto empty paddock and three steers were added in June. The animals received no acaricidal treatment; information on their tick infestations has already been published (Wilkinson 1955).…”

Infestação experimental de equinos por Rhipicephalus (Boophilus) microplus

“…Isso talvez possa ocorrer quando não houver, naquele local, outra espécie de hospedeiro preferencial (LABRUNA et al, 2001) e também esteja presente a condição de susceptibilidade individual do hospedeiro, como observado neste estudo e previamente descrito em bovinos por WILKINSON (1955).…”

Relationship Between Resistance to Boophilus Microplus, Nutritional Status, and Blood Composition in Shorthorn X Hereford Cattle

“…It is now well established that there are marked differences between breeds of cattle in their resistance to the cattle tick, Boophilus microplu8, and also that within breeds there are wide animal variations in susceptibility to tick infestation (Wilkinson 1955;Riek 1962;Francis and Little 1964;Roberts 1968). However, the mechanism of tick resistance in cattle remains largely undetermined.…”