Risk of lungworm in unvaccinated calves and cattle

What is Lungworm?

Lungworm is a nematode that can affect many species of animals including sheep, cattle, deer, goats and horses. Each species typically has associated species of lungworm that it is susceptible to. The bovine lungworm called (Dictyocaulus viviparus) is the most common cause of lungworm in cattle.

Depending on species, lungworms reside in the bronchi and bronchioles of the lungs (and sometimes heart) where they lay eggs. These eggs are coughed up and swallowed into the GI tract, where they turn into the larvae. These larvae is then excreted by cattle onto pastures, where they develop into infective larvae within only 4-6 days. They can either be consumed from the pasture or make use of sporulating Pilobilus fungi to disperse themselves. This means lungworm can spread quickly within a herd, as they incubation time is short and they do not require an intermediate host.

Outbreaks are associated with wet summer weather, which June has been full of! Due to this, ensure you are observant of your cattle and watch out for signs of lungworm (listed below).

What are the signs of Lungworm in cattle?

Infection with lungworm can lead to a condition seen in cattle known as ‘husk’ or parasitic bronchitis. Signs of lungworm in cattle are a dry cough, increased breathing rate and difficulty breathing, rapid weight loss or loss of body condition and in bad infections sudden death. If you suspect lungworm due to these signs, we strongly advise you to call your vet.

Can I test my cattle for lungworm?

There are multiple ways to confirm infection with lungworm, from post mortem to testing faeces, saliva, serum and milk. At RRL we can perform a lungworm test to confirm the presence or absence in your animals faces. If you would like to get your cattle tested, click here.

What can I do to prevent Lungworm in cattle?

  • If you are letting your herd out onto pasture you know has had lungworm in the past, it can be good practice to first vaccinate immature calves.
  • Vaccinating mature calves if they have arrived from other farms and not been exposed to lungworm
  • Consider implementing a strategic anthelmintic dosing program to make sure your cattle are always covered. NADIS has some good advice on how to establish this type of program.

If you’d like to learn more about lungworm, watch this NADIS webinar full of great information!

How do I treat lungworm?

If you have a cow with signs or your herd are showing signs get a confirmation of diagnosis from the vet prior to treatment. You must then treat the entire grazing group or herd with an anthelmintic licensed to treat lungworm in cattle.

You may need to treat the symptoms caused by lungworm infection with anti-inflammation medication or antibiotics.

Remove your cattle (if possible) from the infected pasture to a clean pasture or barn.

Culturing Lungworm at Ridgeway

We can culture lungworm at our facility. We have recently cultured Dictyocaulus filaria ( a sheep lungworm) to produce larvae for a study. Please get in contact with us if you require this service.

Lungworm in other species

If you’d like to know more about lungworm in other species, see our articles about Lungworm in sheep and Lungworm in cats and dogs.




McLeonard C, van Dijk J. Controlling lungworm disease (husk) in dairy cattleIn Practice 2017;39:408-419.

McNulty, S., Strübe, C., Rosa, B. et al. Dictyocaulus viviparus genome, variome and transcriptome elucidate lungworm biology and support future intervention. Sci Rep 6, 20316 (2016).