Dairy cattle-Spinose ear tick

Otobius megnini

Biology The spinose ear tick migrates, in the larval stage, to the head of the animal. The immature stages will attach and then feed within the folds of the ear. After mating, mature adults drop off, and the females lay several batches of eggs on the ground over the next year. While there are no known diseases transferred by the spinose ear tick, they do feed on the host for over 200 days. Moderate or worse infestations can lead to decreased weight gain and reduced milk production, and there is a risk of secondary infections developing at the feeding sites.

Management-chemical control

Ear tags

  • beta-cyfluthrin/piperonyl butoxide ear tag (CyLence Ultra)-Apply one tag to each ear of animals older than 3 months when ticks are present. Remove tags at end of season or before slaughter.
  • permethrin ear tag (GardStar Plus)-Apply one tag to each ear of animals when pests appear. Remove tags at end of fly season or before slaughter.
  • zetacypermethrin/piperonyl butoxide ear tag (PYthon)-Apply one tag to each ear of all animals over 3 months of age when ticks appear. Remove tags at end of season or before slaughter.

Pour-ons, sprays, backrubbers, dusts

  • pemethrin spray, ready-to-use (Catron IV; Prozap Screw Worm Ear Tick Aerosol: Durvet Screw Worm Aerosol)-Spray downward directly into animal's ear. Retreat as necessary.
  • permethrin spray, concentrate (various manufacturers; 10%-40%)-Dilute in water as directed. Spray animal as directed. Typical application interval is 14 days, as needed, but follow label.
  • permethrin pour-on (various manufacturers; 1%-10%)-Apply to animal as directed. Typical application interval is 14 days, as needed, but follow label.
  • permethrin backrubber/self-oiler (various manufacturers; 1%-40%)-Use undiluted or dilute in oil as directed. Recharge as needed.
  • zetacypermethrin/piperonyl butoxide dust (PYthon)-Apply 1/3 oz (1 T) directly to inside of each ear. Repeat as needed but not more often than once every 3 days.