Determination of resistance status to amitraz in the cattle tick Rhipicephalus (Boophilus) microplus from Luzon, Philippines, through bioassay and molecular analysis
Issue Date
3-2021
Abstract
Tick infestations and tick-borne diseases are among the leading causes of economic losses in the cattle industry worldwide. Amitraz is one of the most commonly used chemical acaricides against the cattle tick Rhipicephalus (Boophilus) microplus. Resistance to amitraz has been reported in many countries but not in the Philippines. This study aimed to determine whether cattle ticks from provinces in northern and southern Luzon, Philippines, are resistant to amitraz. Engorged or nearly engorged female ticks were collected from 21 farms and allowed to lay eggs to produce larvae. Larval packet test (LPT) was performed using three concentrations of amitraz, as well as a negative control (diluent). Reverse-transcription polymerase chain reaction (RT-PCR) was also performed to amplify a fragment of the octopamine/tyramine receptor gene and was subjected to sequence analysis by multiple nucleotide and amino acid sequence alignments together with reference strain, amitraz-susceptible strain, and amitraz-resistant strain reported in other countries. LPT results suggest the absence of resistance in all of the tested populations. Interestingly, analysis of the octopamine/tyramine receptor amino acid sequence revealed four out of 14 larval pools having substitutions similar to that of the reported amitraz-resistant strains. Although no apparent resistance was observed in this study, prudent use of amitraz should be practiced as the development of resistance is still likely to occur in the future.
Source or Periodical Title
Experimental and Applied Acarology
ISSN
1688162
Volume
83
Issue
3
Page
399-409
Document Type
Article
Language
English
Subject
Acaricide resistance, Amitraz, Cattle tick, Rhipicephalus (Boophilus) microplus
Recommended Citation
Alota, S.L., Edquiban, T.R.J., Galay, R.L., Bernardo, J.M.G., Sandalo, K.A.C., Divina, B.P., Tanaka, T. (2021). Determination of resistance status to amitraz in the cattle tick Rhipicephalus (Boophilus) microplus from Luzon, Philippines, through bioassay and molecular analysis. Experimental and Applied Acarology, 83 (3), 399-409. 10.1007/s10493-021-00593-8.
Identifier
10.1007/s10493-021-00593-8
Digital Copy
yes
En – AGROVOC descriptors
Acaricide resistance; Amitraz; Cattle tick; Rhipicephalus (Boophilus) microplus.