John H. Pruett

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In this study, acetylcholinesterases (AChEs) were extracted from two Mexican Boophilus microplus strains that demonstrated resistance to the organophosphate (OP) acaricide, coumaphos, in bioassay. The rate of inhibition of the extracted AChEs by the diethyl-OP paraoxon was determined for two resistant strains and two susceptible strains of B. microplus. The(More)
This manuscript provides a summary of the results presented at a symposium organized to accumulate information on factors that influence the prevalence of acaricide resistance and tick-borne diseases. This symposium was part of the 19th International Conference of the World Association for the Advancement of Veterinary Parasitology (WAAVP), held in New(More)
Nine Hereford calves were infested with Psoroptes ovis and were allowed to develop clinical mange during a 9-week period. Blood, serum, and urine samples were obtained before and after calves were infested and were compared with those from 3 noninfested control calves. All calves were euthanatized and necropsied 9 weeks after they were infested. Gross and(More)
A strain of Mexican Boophilus microplus (Cz) collected near Coatzacoalcos, Veracruz, Mexico, exhibits a moderate, but significant, level of permethrin resistance. Unlike other highly permethrin resistant strains, the Cz strain does not have a mutation within the sodium channel gene that results in target-site insensitivity. However, the Cz strain possesses(More)
Rhipicephalus (Boophilus) microplus cDNAs, BmAChE1, BmAChE2, and BmAChE3, were previously identified as presumptively encoding acetylcholinesterases (AChEs), but biochemical identity was confirmed only for recombinant BmAChE3. In the present study, four recombinant BmAChE1 constructs and single recombinant constructs of BmAChE2 and BmAChE3 were expressed in(More)
Mutations were identified in the cDNA sequence encoding the acetylcholinesterase BmAChE3 in strains of Rhipicephalus (Boophilus) microplus (Canestrini) resistant or susceptible to organophosphate (OP) acaricide. The mutation that occurred most frequently in the OP-resistant San Román strain resulted in a substitution of glutamine (Q) for arginine (R) at(More)
  • J H Pruett
  • International journal for parasitology
  • 1999
The control of arthropod ectoparasites of livestock by systemically delivered chemicals was introduced in the 1950s. Their low cost, ease of use, and high level of efficacy ensured dependence upon them for ectoparasite control. However, current societal and scientific concerns regarding dependency upon chemicals have emphasised the need for the evaluation(More)
This report is designed to provide additional information regarding larval soluble proteins toward the planned development of a comprehensive database of Rhipicephalus (Boophilus) microplus proteins that elicit a humoral immune response in cattle as a result of natural ectoparasite infestation. Larval proteins of R. microplus are complex and the protein(More)
Cattle grub larvae are able to survive a lengthy 8 1/2-mo internal migration within the naive bovine host connective tissues. Larval survival is observed even in the presence of host immunological responses to principal parasite proteins. In this study, data are presented that suggest that a digestive enzyme, hypodermin A, of the first-instar larvae(More)
The complete cDNA sequence encoding a Boophilus microplus (Canestrini) (Acari: Ixodidae) acetylcholinesterase (AChE3) was expressed in the baculovirus system. The recombinant AChE3 protein (rBmAChE3) was secreted as a soluble form into the cell culture medium and was identified as a functional AChE by substrate specificity and by inhibition with the(More)