Ectoparasites Flashcards
Name a chewing louse seen in sheep
Bovicola ovis
Name some environmental risk factors for Bovicola ovis infestation
Warm, dry weather
Dark housing
How is Bovicola ovis treated? Do all sheep need treating?
Deltamethrin (synthetic pyrethroid pour-on)
Or diazinon dip (OP)
Treat all if indoors, treat worst affected if outdoors
Which mites are found on the ventral abdomen and scrotum, causing pruritis and infertility?
Chorioptes bovis
What is the treatment for Chorioptes bovis?
OP dip (diazinon)
How is Chorioptes bovis diagnosed?
Skin scrape
What flies cause Flystrike?
Lucillia sericata
When does Flystrike typically occur?
May-October
Name some risk factors for flystrike
Faecal soiling on wool
Warm, humid temperatur
Carcasses on farm (attract flies)
What is the treatment for flystrike and headflies?
Deltamethrin (synthetic pyrethroid) Or diazinon (OP dip) Insect growth regulators Clean wounds Supportive care
How can headflies and flystrike be prevented?
Shearing
Dagging
Tail docking
Fly and other parasite control
What fly in sheep affects the base of the the horns?
Headfly - Hydrotea irritans
What are the clinical signs of Hydrotea irritans in sheep?
Affected horn base
Occular discharge
Ovine sweet itch is uncommon. What is sweet itch?
Hypersensitivity to Culicoides midges
What causes Sheep Scab?
Psoroptes ovis mites
When is Sheep Scab more prevalent?
Autumn, Winter months
Sheep Scab may cause an allergic reaction to the site 6-8 weeks post-infection. Where on the body are Psoroptes predisposed to?
Flanks
Dorsum
(or whole sheep)
How can Sheep Scab be diagnosed?
Wool pluck or skin scrape from edge of lesion
ELISA - (requires 12+ sheep)
What is the treatment for sheep scab? How much of the flock should be treated?
Diazinon (OP dip)
Ivermectin, moxidectin (MLs)
Dexamethasone if severe/allergic reaction
ALL of flock
What is the treatment for all sheep ectoparasites?
Diazinon - OP dip
Deltamethrin - SP pour on
(and ivermectin +/- dexamethasone for Sheep Scab)
Give examples of vectors that spread tick-borne diseases
Ixodes ricinus
Dermacentor reticulata
Haemphyllis punctuate
Extra-care should be taken with which stock around tick-borne diseases?
Young, naive stock
Give oxytetracycline before going into tick area
What is the treatment for ticks in sheep?
Diazinon (OP dip)
Deltamethrin (SP pour-on)
Louping ill is caused by which virus and is spread in which seasons?
Flavivirus
Spring, Summer, Autumn
How can louping ill be prevented?
Tick prevention
Vaccine
What pathogen causes the tickborne diseaes Q-fever?
Coxiella burnetti
Flu symptoms in humans
What pathogen causes tick-borne fever? Do animals develop immunity to this?
Analasma phagocytophilia
Yes develop immunity - naive animals susceptible
Which Tickborne disease is most common in Autumn and causes profound immunosuppression, fever, infertiliy in rams and abortion in ewes?
Tickborne Fever
Anaplasma phagocytophilia
What pathogen causes tick pyaemia?
Staph aureus
What does tick pyaemia (Staph aureus) cause in lambs?
Polyarthritis/joint ill
Spinal abscesses
