ATTRACTIVITY OF CATTLE INFESTED BY AMBLYOMMA-VARIEGATUM (ACARI, IXODIDAE) FOR CONSPECIFIC ADULT TICKS FROM THE FIELD IN GUADELOUPE

Four field experiments were conducted with creole cattle in Guadeloupe to study the attractivity for adult ticks of animals previously infes ted with males of Amblyomma variegatum producing aggregation attachmen t pheromones (AAPs). In each experiment, two groups of cattle were use d; the first group was infested with adult A. variegatum and the secon d group was kept free of ticks and pheromones by acaricidal treatment and by washing the hair and skin of previously infested sites. Both gr oups were then exposed to natural infestation by ticks present in the environment or by ticks bred in the laboratory and released on the pas ture. The number of additional ticks infesting animals were compared b etween the treated and control groups. There were no significant diffe rences between both groups in the numbers of new male ticks infesting the animals during the first days following the beginning of the exper iment. Thereafter, comparison of the slopes of infestation indicated t hat infested cattle were no more attractive for male ticks than uninfe sted hosts. Uninfested cattle were spontaneously and rapidly infested by male ticks. It is concluded that carbon dioxide or another host com ponent was a major attractant for A. variegatum males. Female ticks at tached on predilection sites exclusively in the presence of AAP-produc ing males, i.e. 5-10 days after the attachment of the first males. Bas ed on these results we postulate that slow-release devices impregnated with pheromones have no additional attractive effect on A. variegatum males under Caribbean conditions. However, they may be useful in indu cing the attachment of females, but only in the first days preceding t he arrival of pioneer AAP-producing males. (C) Chapman & Hall Ltd.