Mariana Fogale de Andrade
Selective control of Rhipicephalus microplus in a dairy
cattle herd from different genetic groups
Mariana Fogale de Andrade1
* ; Rodrigo Giglioti1
; Gunta Gutmanis1
; Bianca Tainá Azevedo1
Cristiane Fernandes de Carvalho Fiorin1
; Anibal Eugênio Vercesi Filho1
; Luciana Morita Katiki1
; Cecília José Veríssimo
1Instituto de Zootecnia – IZ, Agência Paulista de Tecnologia dos Agronegócios – APTA, Nova Odessa, SP, Brasil
Alternatives for Rhipicephalus microplus control are needed in the light of its resistance to acaricides. One of the
ways to decrease the use of acaricides in a herd is selective control (SC). In the present study, SC was evaluated
in a dairy herd consisting of different genetic groups: Holstein, Jersey, crossbreed and Girolando. Ticks were
counted in the right anterior third region on around 90 cows, totaling nine evaluations at intervals of 21 days.
Commercial pour-on acaricide was applied only when the infestation was greater than or equal to eight ticks
larger than 4 mm in the anterior third region. Tick counts were transformed into log10 and analyzed using mixed
models. There was significant difference among groups: Holstein had the highest averages of tick numbers, as
expected, although 34.3% did not receive tick treatment. In the other groups, SC reduced the use of acaricides
by 79.1% for crossbreed, 81.5% for Jersey and 94.9% for Girolando. The criterion used for applying the acaricide
successfully kept the tick population under control. The great advantage of SC was savings to the system, without
harming the animals, in addition to generate fewer residues in the animals and in the environment.
Keywords: Cattle, tick, alternative control, partial treatment of the herd.