Chevillon Christine auteur aut IRD Ducornez S. auteur aut IRD De Meeûs Thierry auteur aut IRD Koffi Brou Basile auteur aut IRD Gaia H. auteur aut IRD Delathiere J.M. auteur aut IRD Barré N. auteur aut IRD text journalArticle eng text/pdf born digital access Rhipicephalus (Boophilus) microplus has been pesticide-controlled for several decades in the pacific island of New Caledonia. Since 1996, pesticide-control has been based on either deltamethrin (Butox (R)) or amitraz (Taktic (R)) in herds harbouring deltamethrin-resistant ticks. In this island, the first R. microplus deltamethrin- and amitraz-resistances were detected in 1992 and 2003, respectively. Using LPT bioassays, we have undertaken to update data regarding the geographical distribution and the physiological diversity likely to be involved in these resistances. We confirmed that after 17 years of intensive use of deltamethrin, several resistances of moderate levels (< 30-fold) have evolved and/or diffused in any part of the island. We also evidenced that amitraz-resistant phenotypes have recently evolved in diverse western tick populations, although none has reached fixation in any tick population yet. According to synergists bioassays, the physiological changes involved in amitraz-resistance in New Caledonia would involve target modification and detoxifying P450 cytochrom oxydase(s). It may also involve detoxifying esterase(s) although this later point will need confirmation on samples bearing higher frequency of resistant phenotypes. Results are discussed with regard to the local evolutionary dynamics of resistance. specialized Rhipicephalus Boophilus microplus resistance deltamethrin amitraz synergists bioassays 052 147 3-4 276-288 2007 0304-4017 https://www.documentation.ird.fr/hor/fdi:010040765 10.1016/j.vetpar.2007.05.003 0304-4017 [F B010040765] https://www.documentation.ird.fr/hor/fdi:010040765 https://www.documentation.ird.fr/intranet/publi/2007/10/010040765.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2007-11-06 2017-08-23 fdi:010040765 fre