The Metabolism of Carbaryl in the Cattle Tick Boophilus Mioroplus (Canestrini)

Abstract

The metabolism of carbaryl has been studied in the engorged adult female cattle tick, B. microplus using 14C·labelled compounds. Forty-eight hours after injection of [carbonyl-14C]carbaryl only 6% of the radioactivity could be recovered in an aqueous acetone extract while 90% was recoverable after an equivalent injection of [1-14C]carbaryl. Hydrolysis of the carbamate ester, hydroxylation, and conjugation were the major metabolic pathways. The radioactivity of the extract was completely accounted for as I-naphthol (55%) and 1,5-dihydroxynaphthalene (45%) after acid hydrolysis. 1,4-Dihydroxynaphthalene appears to be absent. Evidence was also obtained for some hydroxylation of the N-methyl group. No unchanged carbaryl could be detected.