Lungworm in Angora goats
By Dr Mackie Hobson BSc(Agric),BVSc

1. Parasites

Lungworm (Dictyocaulus filarialhas) is uncommon but has been diagnosed in Angora goats in late summer after a good season in the Karoo and more commonly on pasture grazed goats. Young previously unexposed goats are most susceptible.

Clinical signs:

• Cough
• Dyspnoea (difficult breathing).
• Can lead to death (often developing into a bacterial pneumonia)
• Survivors - weight loss and often remain ‘poor doers’.
• Most goats recover

How is lungworm spread?

Adult females in the bronchi (airway of the goat) lay eggs which hatch in the bronchi. The larvae are coughed up and are swallowed and are passed out in the faeces. The larvae can develop in the faeces over a week (warm, moist conditions favour survival and spread).

The larvae can spread in water or mechanical transmission.

Carrier goats

Adult goats can become immune to further infection while others remain with sub-clinical infections
leading to pasture contamination.

What does the lungworm do to the goat’s lung?

The lungworm can cause blockage of the airway with inflammatory exudate (eosinophils) and mucous, in response to the larvae. The goat may develop emphysema and lung oedema.

The irritation caused coughing and leads to the development of pneumonia, found more in the
caudal lobes.

Diagnosis of Lungworm

• In Angora goats this is usually diagnosed on Post Mortem finding. (Often incidental in poor doers).
• Laboratory testing: Baermann technique the method of choice, ELISA antibody tests
• Larvae are often not found in the faeces when doing microscopic checks

Treatment of Lungworm Infection

• Broad-spectrum anthelmintic (see website benzimidazoles and macrocyclic lactones https://www.angoras.co.za/article/anthelmintic-drug-list-2019
• Antimicrobials for secondary bacterial infections
• Anti-inflammatory drugs as needed

Control of Lungworm

Lungworm infections in flocks are controlled primarily anthelmintics.

Reference:
MSD Veterinary manual