Nematodes of dogs

Question 1

What group of nematode worms does Toxocara Canis belong to and where can it be found?

Answer 1

Ascarid and in the small intestine

Question 2

What is its clinical significance?

Answer 2

Puppies can be born with it and large numbers can cause diarrhoea, vomiting etc

Question 3

What is the life cycle of Toxocara Canis in young dogs?

Answer 3

Eggs in faeces, Larvae undergo hepato-tracheal migration and then adults are in small intestine.

Question 4

What is the life cycle of Toxocara Canis in older dogs?

Answer 4

The larvae migrate through the body to somatic tissues causing granulomatus reactions. Somatic larvae are in arrested state and produce a lot of antigens to distract the immune system. They become activated when bitch reaches day 42 of pregnancy, some go to the placenta to effect foetus and others got to the mammary gland.

Question 5

What drug is used to control Toxocara Canis?

Answer 5

fenbendazole

Question 6

What species does toxascaris leonine infect

Answer 6

Dogs and cats

Question 7

How do you tell the difference between the eggs of toxascaris and those of toxocara?

Answer 7

Toxascaris eggs are smooth and pale whilst toxacara eggs are dark and pitted.

Question 8

Describe the morphology of hookworms

Answer 8

They are bursate and 1-2cm. They have a large buccal cavity and teeth,

Question 9

How do hookworms infect the host?

Answer 9

Either by attaching and skin penetration or ingestion?

Question 10

What is the main species of hookworm seen in the UK?

Answer 10

Uncinaria

Question 11

Give a brief description of Trichuris Vulpis

Answer 11

A whip worm that causes intermittent diarrhoea.

Question 12

Toxocara Cati infect what species?

Answer 12

Cats

Question 13

compare toxocara cati to toxocara canis

Answer 13

Similar in morphology but cati has no prenatal transmission. Somatic larvae can accumulate in a wide range of paratenic hosts.