title: Rhipicephalus (Boophilus) microplus resistant to acaricides and ivermectin in cattle farms of Mexico.
abstract: Ticks and the diseases they transmit cause great economic losses to livestock in tropical countries. Non-chemical control alternatives include the use of resistant cattle breeds, biological control and vaccines. However, the most widely used method is the application of different chemical classes of acaricides and macrocyclic lactones. Populations of the cattle tick, Rhipicephalus (Boophilus) microplus, resistant to organophosphates (OP), synthetic pyrethroids (SP), amitraz and fipronil have been reported in Mexico. Macrocyclic lactones are the most sold antiparasitic drug in the Mexican veterinary market. Ivermectin-resistant populations of R. (B.) microplus have been reported in Brazil, Uruguay and especially in Mexico (Veracruz and Yucatan). Although ivermectin resistance levels in R. (B.) microplus from Mexico were generally low in most cases, some field populations of R. (B.) microplus exhibited high levels of ivermectin resistance. The CHPAT population showed a resistance ratio of 10.23 and 79.6 at lethal concentration of 50% and 99%, respectively. Many field populations of R. (B.) microplus are resistant to multiple classes of antiparasitic drugs, including organophosphates (chlorpyrifos, coumaphos and diazinon), pyrethroids (flumethrin, deltamethrin and cypermethrin), amitraz and ivermectin. This paper reports the current status of the resistance of R. (B.) microplus to acaricides, especially ivermectin, in Mexican cattle.
authors: Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Yucatán, Mérida, Yucatán, México.
authors: Róger Iván
authors: RI
authors: Rodríguez-Vivas
authors: Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Yucatán, Mérida, Yucatán, México.
authors: Luis Carlos
authors: LC
authors: Pérez-Cogollo
authors: Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Yucatán, Mérida, Yucatán, México.
authors: José Alberto
authors: JA
authors: Rosado-Aguilar
authors: Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Yucatán, Mérida, Yucatán, México.
authors: Melina Maribel
authors: MM
authors: Ojeda-Chi
authors: Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Yucatán, Mérida, Yucatán, México.
authors: Iris
authors: I
authors: Trinidad-Martinez
authors: Cattle Fever Tick Research Laboratory, USDA, Edinburg, USA.
authors: Robert John
authors: RJ
authors: Miller
authors: Knipling-Bushland U.S. Livestock Insects Research Laboratory, USDA, ARS, Kerrville, USA.
authors: Andrew Yongsheng
authors: AY
authors: Li
authors: Knipling-Bushland U.S. Livestock Insects Research Laboratory, USDA, ARS, Kerrville, USA.
authors: Adalberto Pérez
authors: AP
authors: de León
authors: Knipling-Bushland U.S. Livestock Insects Research Laboratory, USDA, ARS, Kerrville, USA.
authors: Félix
authors: F
authors: Guerrero
authors: FEPAGRO Saúde Animal. Laboratório de Parasitologia, Eldorado do Sul, RS, Brasil.
authors: Guilherme
authors: G
authors: Klafke
mesh_terms: D056810:Acaricides / Q000494:pharmacology* / Q000627:therapeutic use; D000383:Agriculture; D000818:Animals; D000977:Antiparasitic Agents / Q000494:pharmacology* / Q000627:therapeutic use; D002417:Cattle; D002418:Cattle Diseases / Q000188:drug therapy; D004351:Drug Resistance; D007559:Ivermectin / Q000494:pharmacology* / Q000627:therapeutic use; D007783:Lactones / Q000494:pharmacology / Q000627:therapeutic use; D008800:Mexico; D048494:Rhipicephalus / Q000187:drug effects*; D013984:Tick Infestations / Q000188:drug therapy / Q000662:veterinary
chemical_list: D056810:Acaricides; D000977:Antiparasitic Agents; D007783:Lactones; D007559:Ivermectin