Ornithodorus spp

From Cow
Adult female Ornithodorus moubata
A stillborn calf which died as a result of epizootic abortion, transmitted by Ornithodorus coriaceus

Ornithodorus spp ticks are one of the more common common skin parasite of cattle in tropical and temperate regions worldwide[1].

Species of Ornithodorus scrub ticks which have been reported in cattle include:

  • O. savignyi (India, Sri Lanka)[2]
  • O. coriaceus (USA, Mexico)[3]
  • O. gurneyi (Australia)
  • O. moubata (Africa)[4]
  • O. porcinus (Africa)
  • O. marocanus (Spain)
  • O. turicata (USA)
  • O. dugesi (USA)
  • O. coriaceus (USA)
  • O. tholozani (Eurasia)
  • O. papillipes (Eurasia)
  • O. crossi (Eurasia)
  • O. tholozani (Mediterranean)
  • O. lahorensis (Eurasia)
  • O. turicata (USA, Mexico)
  • O. furucosus (South America)
  • O. braziliensis (South America)
  • O. rostratus (South America)

As well as causing 'tick worry' and skin disease, these ticks are vectors for Epizootic bovine abortion (Borrelia crocidurae & Myxobacteria spp)[5], Rickettsia spp, Anaplasma spp, Babesia spp, Trypanosoma spp, Theileria spp, Francisella tularensis (Tularaemia), Q fever, human haemorrhagic fever, sawgrass virus and Powassan virus.

Control of this parasite is usually effective with topical acaricides such as ivermectin, doramectin and fipronil[6]. Commercial vaccines are also being tested in cattle and are showing promise.

Commercially available synthetic acaricides are commonly used, but indiscriminate practices in their application have resulted in the rapid evolution of resistance. Although single acaricide treatment can destroy all of the ticks on an animal, they will not prevent reinfestation.

The infested pasture must remain free of all livestock for 6 to 9 months or longer, to break the tick life cycle.

References

  1. Merck Vet Manual
  2. Sutherland IH (1990) Veterinary use of ivermectin. Acta Leiden 59(1-2):211-216
  3. Kennedy PC et al (1983) Epizootic bovine abortion: histogenesis of the fetal lesions. Am J Vet Res 44(6):1040-1048
  4. Klingler J & Friedrich T (1997) Site-specific interaction of thrombin and inhibitors observed by fluorescence correlation spectroscopy. Biophys J 73(4):2195-2200
  5. Hall MR et al (2002) Diagnosis of epizootic bovine abortion in Nevada and identification of the vector. J Vet Diagn Invest 14(3):205-210
  6. Kiss T et al (2012) Tick prevention at a crossroad: new and renewed solutions. Vet Parasitol 187(3-4):357-66