Control of Dermacentor nitens using a commercial formulation of Metarhizium anisopliae
ABSTRACT. Perinotto W.M.S., Camargo M.G., Golo P.S., Angelo I.C., Quinelato S., Monteiro C.M.O., Sá F.A., Coutinho-Rodrigues C.J.B., Marciano A.F., Fiorotti J. P. & Bittencourt V.R.E.P. [Control of Dermacentor nitens using a commercial formulation of Metarhizium anisopliae.] Controle de Dermacentor nitens utilizando uma formulação comercial à base de Metarhizium anisopliae. Revista Brasileira de Medicina Veterinária, 35(Supl. 2):35-42, 2013. Departamento de Parasitologia Animal, Instituto de Veterinária, Anexo 1, Universidade Federal Rural do Rio de Janeiro, Campus Seropédica, BR 465, Km 7, Seropédica, RJ 23890-000, Brasil. E-mail: firstname.lastname@example.org Dermacentor nitens ticks are commonly found in the equine auditory canal. This ectoparasite causes substantial economic losses due to its direct damage caused by the parasitism, transmission of pathogens, and embargoes during marketing and transport of horses. Metarhizium anisopliae senso latu (s.l.) is a cosmopolitan entomopathogenic fungus, which has been used to control ticks, in vitro. Studies have shown that when formulated these entomopathogenic fungi reach an improved percent of control against ticks and insects, what is essential to drive in vivo studies and obtain good results in the field. This scenario has aroused the interest of industries that have developed different formulations of entomopathogenic fungi. Metarril WP® is a commercial product based on M. anisopliae spores used in agricultural pest control, but little is known about their effect against ticks. Accordingly, this study aimed to evaluate the effects of this product on partially engorged females, eggs and larvae of D. nitens. The formulations were prepared following manufacturer’s recommendations and adjusted to 107 and 108 conidia mL-1, increased by 10 or 0.5 % mineral oil. The biological parameters of engorged females (posture weight, egg production index and nutritional index) were significantly reduced by 10% oily formulations at 107 and 108 conidia mL1 . Different treatments using Metarril WP® product yielded control percent of partially engorged females ranging from 10.57 % to 82.48 %. Formulations containing mineral oil also demonstrated high efficacy against eggs and larvae of D. nitens. Metarril WP® formulated in mineral oil showed to be effective against D. nitens in different developmental stages. This is the first report of the effect of this commercial product againstD. nitens ticks.