Data from: Prevalence of and potential risk factors for multiple resistance to acaricides in Rhipicephalus (Boophilus) microplus ticks: A survey in the state of Rio Grande do Sul, Brazil

Teixeira Ferreira, Priscila 1 ; de Bem Bidone, Nathalia2; Groff, Fernando2; Silva da Silva, Patrícia1; Silveira de Jesus, Mariana1; da Cruz Payao Pellegrini, Debora3; Laureano Doyle, Rovaina1; Reck, José1; Klafke, Guilherme1

Published Dec 09, 2025 on Dryad. https://doi.org/10.5061/dryad.sj3tx96dd

Data files

Dec 09, 2025 version files 50.23 KB

Raw_Data_INQR.csv

46.32 KB
README.md

3.91 KB

Abstract

The cattle tick Rhipicephalus (Boophilus) microplus (Canestrini, 1887) (Ixodida, Ixodidae) is responsible for significant economic losses in bovine production in tropical and subtropical regions worldwide. Control of this tick predominantly involves the use of chemical acaricides; however, their indiscriminate use has led to the selection of resistant populations. A survey on tick populations was conducted in the state of Rio Grande do Sul in Brazil to assess the prevalence of multiple resistance to acaricides (MRA) in cattle farms. Additionally, questionnaires were administered to identify potential risk factors associated with MRA. In total, 176 farms with a bovine population of >40 cattle were randomly assigned for tick sampling. The resistance to six acaricidal compounds was investigated by bioassays. A larval packet test was performed for amitraz, chlorpyrifos, cypermethrin, fipronil, and ivermectin. Fluazuron was screened using an adult immersion test. MRA (i.e., resistance to three or more compounds) was detected in 173 samples, representing 98.3% of the total samples. Among these samples, 125 (71%) showed resistance to all six compounds tested (MRA-6). Additionally, we classified the resistance intensity into four levels (I to IV) based on the quartile distribution of the bioassay data. Ten samples showed high and extremely high levels (III and IV) of resistance to all six compounds tested. Two variables were significantly associated with multiple resistance to all six compounds tested: use of injectable acaricides and six or more acaricide treatments per year. These results regarding widespread resistance and the emergence of MRA ticks are alarming and highlight the significant challenge of tick control in southern Brazil.

Dataset DOI: 10.5061/dryad.sj3tx96dd

Description of the data and file structure

Larval packet test and an adult immersion test were performed to identify multiple resistance in tick samples. Questionnaires were administered to farmers to identify potential risk factors associated with multiple resistance as well. File structure with information about sample identification, bioassays, and questionnaire answers.

Files and variables

File: Raw_Data_INQR.csv

Description:

Variables

Sample: Number of the sample
Hectare: Hectare area of the farm (unit: hectare)
Number_of_animals: Number of animals in the farm
Cypermethrin - Amitraz: Result of mortality rate (unit: %) in larval packet test (LPT) due to acaricides
Fluazuron - Result of in vitro efficacy (unit: %) in adult immersion test (AIT) due to fluazuron
Municipality: Municipality of the farm (name of the city)
Cattle: Cattle prodution (beef, dairy, mixed of beef and dairy production)
Prodution system: Prodution system (full cycle, calf and stocker cattle operations)
Pasture: Pasture (native pasture, cutivated pasture, native and cutivated pasture, feedlot)
Breed: Breed (taurine, zebu, crossbreed)
Buy_animals: Farmers buy animals from external sources (yes, no)
Quarantine: Quarantine after buying animals (if yes for Farmers buy animals from external sources, yes, no, n/a)
Acaricide_treatment_after_buy_animals: if yes for Farmers buy animals from external sources, yes, no, n/a
Dip_vap_active: dip vap active in the farm (yes, no)
Type_of_acaricide_treatment: Type of acaricide treatment applied in the farm (dip vap, spraying mannual, spraying automatic, injectable, and/or pour on)
Acaricides: name of acaricides used in the cattle (amitraz, cypermethrin/deltamethrin, cypermethrin+DDVP, DDVP+clorfenvinphos, cypermethrina+clorpiriphos, macrocyclic lactones, fipronil, and/or fluazuron)
Number_treatments_last_year: Number of acaricide treatments in the last year
Control strategies: controlled burning, bush hogging, rotational grazing, spelling pasture and/or crop-livestock system, none
Veterinary_assistance: Veterinary assistance for the farmers (yes, no)
Control_by_vet: Tick control by vet (if yes for Veterinary assistance, then yes, no, n/a)
Previous_bioassays: Previous bioassays applyed in the tick populations at the farm (yes, no)
Babesiosis_and_Anaplasmosis: History of Babesiosis and Anaplasmosis in the animals of the farm (yes, no)
Number_cases_of_those_diseases: Number of cases of those diseases in the animals of the farm (if yes for History of Babesiosis and Anaplasmosis in the animals of the farm, the number of cases or n/a)
Number_dead_animals_thoses_diseases:Number of dead animals because of thoses diseases in the animals of the farm (if yes for History of Babesiosis and Anaplasmosis in the animals of the farm, the number of dead animals or n/a)

N/a = not applicable

Note 1: semicolon-delimited with comma decimal

Note 2: samples were categorised in the paper as resistant if the mortality rate (for cypermethrin, clorpyriphos, fipronil, ivermectin, amitraz), and in vitro efficacy (for fluazuron) was < 95%

Code/software

PoloPlus (LeOra Software, 2004)

Microsoft Excel

VassarStats (http://www.vassarstats.net/odds2x2.html)

SPSS version 20 (IBM SPSS Statistics Base v.20; IBM Corp., Armonk, NY, USA)

ArcGIS 10.5 (ESRI, Redlands, CA, USA)

non-fixed Silvermans bandwidth (Silverman, 1986)

Access information

Other publicly accessible locations of the data:

Data was derived from the following sources: