Histochemical Localization of Esterases in the Integument of the Female Boophilus microplus (Acari: Ixodidae) Tick

Department of Veterinary Pathobiology, College of Veterinary Medicine, Texas A&M University, College Station 77845-4467, USA.
Journal of Medical Entomology (Impact Factor: 1.82). 12/2001; 38(6):780-2. DOI: 10.1603/0022-2585-38.6.780
Source: PubMed

ABSTRACT The cattle tick Boophilus microplus (Canestrini) is one of the most important ectoparasites affecting tropical cattle with worldwide distribution. Application of organophosphate compounds (OP) is extensively used as a tick control method. However, the appearance of ticks resistant to the OP decreases the therapeutic efficacy of such compounds. Esterases have been implicated as potential biochemical mechanisms for detoxification in B. microplus larvae. We found increased esterase activity in the inner layers of the integument of OP resistant adult female B. microplus ticks as compared with the OP susceptible ticks. We discuss the potential role of these enzymes during acaricide metabolism and propose future research.

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