Strongyles 1 Flashcards
What are small strongyles of horses called?
Cyathostomins
What is Cyathostomin biology?
*Free living stages on pasture
*Parasitic stage within large intestine of horse
*Horses have no immunity
What are the typical size of cyathostomin eggs, L3 + adults?
Eggs = 80-100microns
L3 = 130microns
Adults = 1cm
What is the life cycle of a cyathostomin?
*Direct
*L3 ingested from pasture - migrate to large intestine develop to L4 in mucosa
*Develop to L5 in lumen of large intestines
*PPP = 6-8weeks
*Eggs shed on pasture
What stage of cyathostomin can hypobiose?
Early L3 stage in mucosa of large intestine
What are factors which may contribute to hypobiosis?
*Cold conditions
*Heavy parasite burden
Age - young horses**
What can be used to treat mucosal stage larvae + hypobiosed larvae?
***Moxidectin
*Panacur - if no benzimidazole resistance
What are the clinical signs of larval cyathostomins?
*Sudden onset diarrhoea + weight loss
*Sudden weight loss / oedema
*Acute diarrhoea, weight loss + collapse
*Colic
What is larval cyathostominosis
Mass emergence of mucosal-stage hypobiosed larvae (L3+L4)
What are predisposed factors to larval cyathostominosis?
*Age <5yrs
*High stocking density
*History of grazing heavily contaminated pastures
When is larval cyathostominosis more likely to be seen?
October - May
How can all ages of horses carry infections?
Horses do not develop strong immunity
What does over dispersion mean?
Small proportion of horses carry majority of parasite population
When is highest egg shedding seen?
Warm weather - July / August
*Peak L3 on pasture = August / September
