Large Animal Respiratory Parasites

Question 1

What can lungworm have a serious impact on? (9)

Answer 1

• Sustainable livestock industry
• Agricultural economy via:
• wool production
• milk production
• carcass quality
• weight gain (inappetence or anorexia)
• costs of drugs, labour and veterinary treatment
• death or culling
• fertility drops
• calving periods extend

Question 2

What is the most common respiratory disease in cattle in the UK?

Answer 2

Lungworm

Question 3

What are the clinical signs of Lungworm, hoose, husk, verminous pneumonia, parasitic pneumonia, parasitic bronchitis? (4)

Answer 3

Range from a mild cough with a slightly increased

breathing rate, to severe persistent coughing, with marked difficulty

in breathing and even death.

Question 4

What is this?

Answer 4

Parasitic pneumonia

Egg deposition/newly hatched larvae

Question 5

Label this image

Answer 5

Question 6

What is this?

Answer 6

Adult lungworm in bronchi

Question 7

What is this?

Answer 7

Emphysemic lung

Question 8

What size are the male and female lungworm?

Answer 8

Female up to 8cm

Male up to 5 cm

Question 9

What is the morphology of D. viviparus

Answer 9

Question 10

What is the taxonomy of lungworm?

Note: Phylum (1), class (1), sub class (2)

Answer 10

Question 11

Define phasmid

Answer 11

posterior cuticular chemoreceptors

Question 12

What are stronglydia known as? why?

Answer 12

Bursate nematodes because males characteristically have a copulatory bursa.

Question 13

Sub class - secernentea

What is the order? (5) sf? (lots)

Answer 13

Question 14

Phylum - nemathelminthes

Class - nematoda (roundworms)

What is the taxonomic classifcation after this? SF, family

Answer 14

Question 15

What is the Life cycle of the cattle Lungworm Dictyocaulus viviparus?

Answer 15

Question 16

What is the pre patent period of Dictyocaulus viviparus?

Answer 16

3-4 weeks

Question 17

What is the epidemiology of D. Viviparus?

Include:

Distribution?

Climate?

Age?

Pilobolous fungi?

Answer 17

•Distribution

–seen mainly in temperate areas.

•Climate

–larvae require moist, cool environment.

–adverse weather conditions decrease larval survival and dispersal.

–larvae can overwinter on pasture like GI nematodes.

•Age

–young animals are more susceptible.

•Pilobolus fungi

• facilitate the spread of lungworms larvae in a pasture

Question 18

What is the current trend in lungworm in the UK?

Answer 18

Rise in immunologically naïve populations who have either not been vaccinated or exposed to low levels of natural infection during their first grazing season.

Question 19

What is the clinical presentation of lungworm in cattle? (4)

Answer 19

Cough, decreased milk production, and weight loss, enlarged lymph nodes (not usually).

Question 20

What is the clinical presentation of lungworm in sheep and cattle? (6)

Answer 20

Cough, dyspnoea, catarrhal bronchitis, weight loss, lethargy. Greyish-green nodules. Goats are most susceptible and can die from pneumonia.

Question 21

What is the clinical presentation of lungworm in horses? (1)

Answer 21

•often seen in horse grazing with donkeys (natural host).

Question 22

What is the clinical presentation of lungworm in pigs? (4)

Answer 22

Dyspnoea, lethargy, weight loss, persistent cough.

Question 23

How can we diagnose lungworm? Both antemortem (6) and postmortem (1)

Answer 23

•Antemortem diagnosis:

–Clinical signs, grazing history

–Demonstration of larvae in faeces

–Tracheal wash

–Bronchoscopy and radiography

–Serological tests

–Failure of antibiotic therapy

•Postmortem diagnosis:

–Demonstration and identification of lungworms & characteristics lung pathology

Question 24

What should be included in the differential diagnosis for persistent respiratory manifestations in animals especially in enzootic areas.’?

Answer 24

Husk

Question 25

What differentials are there for lungoworm? (7)

Answer 25

* Lung abscess * Lung tumor * Bacterial bronchopneumonia * Necrobacillosis * Tuberculosis * Actinobacillosis * Hydatid disease

Question 26

What are the treatment options for: D. Viviparus? F. Filaria? D. Arnfieldi? M. Apri?

Answer 26

Question 27

What is your 1st choice for treatment of lungworm in dairy?

Answer 27

Eprinomectin

Question 28

Which treatment will you avoid using in dairy cows with lungworm?

Answer 28

Macrocyclic lactones - kills quickly and measn you get a build up of dead ones

Question 29

What are the control strategies for lungworm? (6)

Answer 29

•Deworming –Strategic deworming using anthelmintics. * Vaccination (Bovilis® Huskvac, Intervet UK Ltd) * Management Options –Supplementary approaches. –Sanitation and management. –Avoid mixing animals/ages on the same pasture. –Elimination of intermediate hosts (doesn’t apply for all lungworm species).

Question 30

What is the vaccine protocol for lungworm?

Answer 30

–One vaccine, made up of irradiated L3 infective larvae. –Two doses, 4wk apart at least 2 wk before animals can be turned out to allow the development of immunity.

Question 31

How to avoid a poor outcome in the management of parasitic pneumonia? (5)

Answer 31

DON’T wait for a husk to develop to suspect the diagnosis. DON’T exclude the diagnosis because there is no history of lungworm infection. DON’T exclude the diagnosis solely for geographic or seasonal reasons DON’T withhold therapy if you are clinically suspicious DON’T administer the vaccine to calves less than 8 weeks old

Question 32

What is the public health relevance of lungworms to humans?

Answer 32

Animal lungworms are strict animal parasites and don’t infect humans. However, there have been rare reports of human infections with the carnivore lung worm Eucoleus aerophilus in Morocco and Russia.

Question 33

What is the public health relevance of lungworm to animals?

Answer 33

Husk is a disease that need never exist given access to clean pasture and a veterinary public health infrastructure that monitors the water/food supply and thwart infections via treatment and vaccination, and elimination of the intermediate/reservoir hosts.

Question 34

What will need to be done in the future with lungworm? (3)

Answer 34

* Pathogenesis of disease –Identify host genetic determinants of resistance (hoping for natural resistance). * Better vaccines (long-lasting immunity) –New targets (e.g. more protective antigens, new virulence factors). * Controlling emergence of resistance –Monitor the development of new anthelmintic resistant strains.