Ectoparasites camelids

Question 1

Which mites are most common with alpacas?

Answer 1

Chorioptes

• Chorioptes bovis
• Surface dwellers
• Mild pruritus, alopecia and scaling of the feet and tail base
• Extension to ventral abdomen, medial limbs and the ears
• Superficial skin scrapes at the margin of lesional areas
• Distinct scaling between toes where mites are carried. Also seen around perineum.
• Can find these mites easily in superficial skin scrapes.

Question 2

Describe scabies in camelids?

Answer 2

• Intensely pruritic
• Sarcoptes scabiei (variant auchinae)
• Pruritus with hyperaemia, papules, pustules with crusting
• Limbs - between the toes, medial thighs, ventral abdomen, chest, axillae, perineum and prepuce
• Zoonotic risk
• Response to macrocyclic lactone therapy? Don’t make good responses with MLs.
• Potentially fatal disease

Question 3

Scabies – diagnosis?

Answer 3

• Superficial skin scrapes (live right at the top of the skin) Only need to find one mite to make a diagnosis.
• Histopathology?
• Response to treatment?
• Predisposing factors?

Question 4

What is this?

Answer 4

Psoroptes

• Pruritus and hair loss is particularly associated with the pinnae and ear canal
• Also shoulders, back, sides, tail head, perineum, nares, axillae, groin, neck and legs
• Psoroptes sp. (not able to readily differentiate from gross morphology)

Question 5

What are some treatments considered for camelids?

Answer 5

• Llamas do not absorb ivermectin (oral or injectable) as well as ruminants
• Successful treatment of alpacas with lice, sarcoptic and psoroptic mange with two injections of moxidectin 7-10 day apart
• Ivermectin at 200 micrograms/kg s/c - variable, usually good effect:
  
  • Psoroptic and sarcoptic mange
  • Sucking lice
  • Concurrent infection of Chorioptes and Sarcoptes in llamas in combination with fipronil
• Llama hair/fibre does not contain lanolin
  
  • Topical applications of insecticidal/acaricidal products used in other ruminants may not be as effective in camelids because no lanolin to keep the active ingredient on body
• Need for pharmacokinetic studies and controlled clinical trials