| a dog naturally infected with rickettsia akari in yucatan, méxico. | rickettsia akari is the causative agent of rickettsialpox, a primarily urban mite-borne rickettsiosis that is encountered in the united states and in a few countries around the world. its vector is the mite liponyssoides sanguineus, which is found on rats and mice, which serve as reservoirs for the disease. in this work we report a severe animal case of r. akari infection with two unusual features: r. akari was found in a dog, and its potential vector was a tick. | 2009 | 19492943 |
| first report of the cattle tick rhipicephalus microplus resistant to ivermectin in mexico. | three cattle farms with ticks, rhipicephalus microplus, thought to be resistant to ivermectin in yucatan, mexico were studied (sfdo, spn, luady). each field-population was collected and tested twice several months apart. the larval immersion test was used on the progeny of collected adult females to test the susceptibility to ivermectin. dose-mortality regressions, lethal concentrations (lc), their confidence intervals and slope were estimated by probit analysis. resistance ratios (rr) were dete ... | 2010 | 19951828 |
| survey of rhipicephalus microplus resistance to ivermectin at cattle farms with history of macrocyclic lactones use in yucatan, mexico. | engorged females of rhipicephalus microplus were collected from 30 cattle farms in yucatan, mexico to evaluate ivermectin resistance. the larval progeny of each tick sample were produced in laboratory and evaluated using the larval immersion test to obtain the larval mortality. concentration-mortality data were subjected to probit analysis to generate lethal concentrations (lc). resistance ratio (rr) of each tick sample was calculated by dividing its lc with that of an ivermectin-susceptible str ... | 2010 | 20570047 |
| the prevalence of pyrethroid resistance phenotype and genotype in rhipicephalus (boophilus) microplus in yucatan, mexico. | a field survey was conducted to evaluate susceptibility of rhipicephalus (boophilus) microplus to cypermethrin on 49 farms in three areas of yucatan, mexico. the modified larval packet test was used to evaluate larval mortality at different cypermethrin concentrations. dose-mortality regressions, lethal concentrations (lc(50)-lc(99)), confidence intervals and slope were estimated by probit analysis. phenotype was defined as susceptible, tolerant or resistant when the resistance factor (rf) deriv ... | 2011 | 21978740 |