Preventative Care: Equine Parasites Flashcards
what is praziquantel effective against?
Anoplocephala perfoliata (tapeworms)
which parasites are of concern now in horses?
cyathostomins (small strongyles)
tapeworms
why do adult horses require individualized attention to their parasite control needs?
vary greatly in their innate susceptibility to infection and level of strongyle egg shedding
what percentage of adult horses are usually shedding 80% of the eggs?
15-30%
how often should all adult horses be dewormed?
twice yearly
how often should horses younger than 3 years be dewormed?
at least 4 times a year
what are the main treatments for ascarids in young horses?
pyrantel
benzimidazoles
why do ascarids cause respiratory disease?
ascarid larval migration
what should you do if you are first deworming a 9-month-old weanling?
administer slow kill dewormer first
then give full dose
what can you use to deworm for cyathostomes in adult horses?
moxidectin
fenbendazole 5 days
what is the most common parasitic intestinal disease in horses?
cyathostomes (small strongyles)
what drug overdosage can cause serious adverse reactions in foals and miniature horses?
moxidectin (quest)
what is moxidectin (quest) useful for?
wide spectrum
encysted cyathostomes
better penetration into intestinal mucosa
what is the chief complaint with Strongylus vulgaris in adult horses?
moderate or severe colic
never dewormed
where do Strongylus equinus migrate?
liver
pancreas
where do Strongylus vulgaris larvae migrate?
arteries
what is the chief complaint with tapeworms in adult horses?
moderate or severe colic
what is the clue with lungworms in adult horses?
donkey contact
what are the main pathogenic mechanisms of lungworms in adult horses?
adult in lung: Dictyocaulus arnfeldi
associated inflammation
how can you diagnose Dictyocaulus arnfeldi?
baermann fecal flotation
microscopic exam: fully formed larvae within egg
TTA or BAL eosinophilic inflammation
how can summer sores in adult horses be treated?
moxidectin
manage sores
what is the chief complaint with pinworms in adult horses?
rubbing tail and hindquarters
how can you treat pinworms in adult horses?
pyrantel
how do the avermectins (zimectrin and quest) work?
paralytic: increase binding of GABA to glutamate-gated chloride channels
rapid influx chloride
what is pyrantel effective against?
large and small strongyles
parascaris
Oxyuris
Srongyloides
anoplocephala double dose
what are thee chief complaints for ascarids in young horses?
unthrifty, rounded abdomen, poor haircoat
nasal discharge or cough
how can you diagnose Parascaris equorum?
fecal flotation: large circular thick-walled eggs
what can you use for Parascaris equorum?
pyrantel: strongid T
fenbendazole: panacur
not ivermectin
what can you use for slow-kill in a young horse (first deworming)?
fenbendazole half dose, 72 hours apart
what are the pathogenic mechanisms of cyathostomes in adult horses?
larvae encyst in colon wall
inflammation as excyst
is there a seasonal occurence of cyathostomes?
yes: as move out of cysts
how can cyathostomes be diagnosed?
fecal flotation: oval egg with morula
what are the main pathogenic mechanisms with Strongylus vulgaris in adult horses?
adult parasite within cranial mesenteric artery
intestinal infarcts, emboli
what are the options with Strongylus vulgaris colic?
resection
euthanasia
which drugs work against Strongylus vulgaris?
iveremctin (zimectrin) or moxidectin (quest)
pyrantel pamoate (strongid T)
fenbendazole (panacur)
what are the main pathogenic mechanisms of tapeworms in adult horses?
adult in distal ileum: Anoplocephala perfiolata
inflammation and hypertrophy wall
ileal impaction
how can you diagnose lungworms in adult horses?
eosinophilic inflammation in TTA or BAL
baermann fecal flotation: oval egg with larva
how can you treat lungworms in adult horses?
avermectins: ivermectin or moxidectin
what causes summer sores?
Habronema spp usually
Onchocerca cervicalis masses
what can you treat pinworms (Oxyuris equi) with?
pyrantel
fenbendazole
not ivermectin
