| effect of moxidectin against natural infestation of the cattle tick boophilus microplus (acarina: ixodidae) in the mexican tropics. | the study was divided in to two trials and carried out in a ranch in eastern yucatan state, mexico. in the first trial, two groups of 15 bostaurusxbosindicus heifers, 6-12 month of age and naturally infested with boophilus microplus ticks were used. heifers in group 1 were treated with a 1% injectable formulation of moxidectin at the dose of 0.20mg/kg body weight by subcutaneous injection. the other group remained as untreated controls. number of immature and engorging female ticks were assessed ... | 2003 | 12531295 |
| prevalence and potential risk factors for amitraz resistance in boophilus microplus ticks in cattle farms in the state of yucatan, mexico. | southern cattle tick, boophilus microplus, control in the mexican tropics is based on the application by spray, dip or pour-on of acaricides. in mexico the first report of ticks resistant to amitraz was reported in 2002. amitraz resistance affecting the cattle industry of yucatan state, mexico, has not been investigated. a cross-sectional study was carried out in order to investigate the possible association between management risk factors and the prevalence of b. microplus ticks resistant to am ... | 2006 | 16730819 |
| 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 |