Fernndez-Salas A.,University of Veracruz |
Rodriguez-Vivas R.I.,University Autnoma Of Yucatn |
Alonso-Diaz M.A.,University of Veracruz |
Alonso-Diaz M.A.,University Autnoma Of Yucatn
Journal of Parasitology | Year: 2012
Abstract: The objectives of this study were: (1) to determine the prevalence and factors associated with Rhipicephalus microplus, resistant to cypermethrin and amitraz, from cattle farms in Veracruz, Mexico, and (2) to determine in vitro mortality percentages of field populations of R. microplus exposed to discriminating doses (DD) of cypermethrin and amitraz. Fifty-three populations of R. microplus were tested by bioassays using DD of cypermethrin (0.05) and amitraz (0.0002). The prevalence of cattle farms with R. microplus ticks that were resistant to cypermethrin and amitraz, and co-resistant to both acaricides, was 90.6, 54.7, and 47.2, respectively. The level of cypermethrin resistance, measured as a survival percentage, was higher as compared to amitraz. Cattle farms with ≤50 animals (odds ratio OR 3.84, 95 confidence interval CI 1.0713.70, P 0.038) and a stocking density of >1 animal unit per ha (AU/ha) (OR 4.21, 95 CI 1.017.71, P 0.050) had a higher probability to develop R. microplus tick populations co-resistant to both acaricides. In conclusion, there is a high prevalence of R. microplus populations on cattle farms in Veracruz, Mexico that are both resistant to cypermethrin and amitraz and co-resistant to both acaricides. The level of cypermethrin resistance is critical, and the exposition variables of ≤50 cattle and a stocking density of >1 AU/ha were factors associated with R. microplus co-resistant to both acaricides. © American Society of Parasitologists 2012.
Gonzlez-Moreno A.,University of Alicante |
Bordera S.,University of Alicante |
Leirana-Alcocer J.,University Autnoma Of Yucatn |
Delfin-Gonzlez H.,University Autnoma Of Yucatn
Environmental Entomology | Year: 2012
The biology and behavior of insects are strongly influenced by environmental conditions such as temperature and precipitation. Because some of these factors present a within day variation, they may be causing variations on insect diurnal flight activity, but scant information exists on the issue. The aim of this work was to describe the patterns on diurnal variation of the abundance of Ichneumonoidea and their relation with relative humidity, temperature, light intensity, and wind speed. The study site was a tropical dry forest at Ría Lagartos Biosphere Reserve, Mexico; where correlations between environmental factors (relative humidity, temperature, light, and wind speed) and abundance of Ichneumonidae and Braconidae (Hymenoptera: Ichneumonoidea) were estimated. The best regression model for explaining abundance variation was selected using the second order Akaike Information Criterion. The optimum values of temperature, humidity, and light for flight activity of both families were also estimated. Ichneumonid and braconid abundances were significantly correlated to relative humidity, temperature, and light intensity; ichneumonid also showed significant correlations to wind speed. The second order Akaike Information Criterion suggests that in tropical dry conditions, relative humidity is more important that temperature for Ichneumonoidea diurnal activity. Ichneumonid wasps selected toward intermediate values of relative humidity, temperature and the lowest wind speeds; while Braconidae selected for low values of relative humidity. For light intensity, braconids presented a positive selection for moderately high values. © 2012 Entomological Society of America.
Villegas-Trejo A.,Servicios de Salud de Morelos |
Manrique-Saide P.,University Autnoma Of Yucatn |
Che-Mendoza A.,Servicios Estatales de Salud de Guerrero |
Cruz-Canto W.,University Autnoma Of Yucatn |
And 5 more authors.
Journal of the American Mosquito Control Association | Year: 2010
Aedes albopictus, Culex corniger, Cx. restuans, and Toxorhynchites theobaldi are reported for the first time for the Mexican State of Morelos. The updated list of species reported is also presented. © 2010 by The American Mosquito Control Association, Inc.
Manrique-Saide P.,University Autnoma Of Yucatn |
Uc V.,University Autnoma Of Yucatn |
Prado C.,University Autnoma Of Yucatn |
Carmona C.,University Autnoma Of Yucatn |
And 6 more authors.
Journal of the American Mosquito Control Association | Year: 2012
We report the collection of Aedes aegypti, Culex quinquefasciatus, Cx. interrogator, Cx. thriambus, Cx. coronator, and Cx. salinarius larvae from storm sewers within an endemic area for dengue transmission in Merida, Mexico, during the rainy season of 2011. This is the first record of the dengue vector Ae. aegypti breeding in storm sewers in the southeast of Mexico. © 2012 by The American Mosquito Control Association, Inc.