Cyathostomins - Small Strongyles (1)

Question 1

What are the hosts?

Answer 1

All equids

Question 2

Describe a small Strongyle egg

Answer 2

60-120 x 35-60 micro m

Question 3

Describe an adult small Strongyle

Question 4

Describe the life cycle

Answer 4

PPP: 1.5-4 months

Larvae more pathogenic stage

Process of going from a L3 to L4 and emerging damages mucosal lining

L3 encyst sin intestinal walls

Arrested development: up to 2.5 years

Question 5

Site of infection

Answer 5

Adults - lumen of large intestine

Larvae - throughout large intestine mucosa

Question 6

Describe the general Pathogenesis

Answer 6

Larval Cyathostomins

Primarily clinical signs associated with emergence of L4

Primarily young animals, older possible

History of horses with syndrome

 - Inadequate treatment during the preceding grazing season
 - Overstocked, highly infective pastures

Mare - origin of infection for a foal

These circumstances result in accumulation of late large burdens of encysted larvae

Each horse has its own supply of mucosal larvae to become next season’s adult

Question 7

Describe the Pathogenesis in Northern temperate climates

Answer 7

Larvae arrest during winter

Emerge as adults during spring

Egg counts increase in spring

Question 8

Describe the Pathogenesis in southern temperate climates

Answer 8

Larvae encyst during summer

Transmission occurs during winter

Question 9

Describe the clinical signs

Answer 9

Diarrhea - L4 can sometimes be seen in diarrheal fluids (reddish mobile
larvae)

Chronic and sudden weight loss

General debility

Weakness

Cachexia (general ill health and malnutrition)

Edema

Intussusception - prolapse of one part of the intestine into the lumen of
an immediately joining part
Colic

Question 10

How do you diagnose?

Answer 10

Egg in fecal - McMaster

- Eggs in feces of foals (

Question 11

How do you treat or prevent?

Answer 11

Som BZs and MCLs for mucosal larval stages

BZs, MCLs, and others for adults

Resistance to all drug classes

Accurate diagnosis required - culture eggs, identify L3

Manage pasture

 - Clean up feces
 - Mixed grazing
 - Do not overstock

Question 12

Explain drug resistance

Answer 12

Survive treatment with an antiparasitic drug that is generally effective against the same parasite species at the same dose and against the same stage of infection

Tolerate the approved dose of antiparasitic drug to which they were previously susceptible due to genetic mutations

Question 13

What is the common name?

Answer 13

Small Strongyles