Lungworm - sheep

Question 1

What are some common spp of sheep lungworm?

To what superfamilies do they belong?

Answer 1

• Dictycaulus filiaria
• Trichostrongyloidea
• Muellerius capillaris
• Metastrongyloidea

Question 2

What are some general features of Dictycaulus filiaria?

Answer 2

• Similar life cycle to D. viviparus
• Direct, L3 is infective, dx L1 in feces
• PPP a little longer though (~5 weeks compared to 4 in D. viviparus)
• Clinical signs milder than D. viviparus
  
  • chronic cough
  • unthriftiness
  • nasal discharge
  • dyspnea in severe cases
• Anterior cuticular knob - diagnostic

Question 3

What are some general features of Muellerius capillaris?

Answer 3

• Widespread and common
• Hair-like worms found in the alveoli
• Indirect LC - molluscs IMH (snails, slugs)
• Not pathogenic
• Lead shot lesions in lungs
• L1’s in feces

Question 4

Since Dictycaulus filaria and Muellerius capillaris are both diagnosed by L1’s in the feces, how do you differentiate the two?

Are both of these spp pathogenic?

Answer 4

• M. capillaris is smaller
• M. capillaris has a dorsal spine on the tail
• No - only D. filaria is pathogenic