Toxocara vitulorum

Question 1

What is Toxocara vitulorum?

Answer 1

A parasitic roundworm affecting cattle and other animals

Specifically known to infect calves.

Question 2

What is the primary transmission route of Toxocara vitulorum?

Answer 2

Trans-mammary route

This route is the major source of infection for calves.

Question 3

What is the size range of male Toxocara vitulorum?

Answer 3

6-25 cm

Question 4

What is the size range of female Toxocara vitulorum?

Answer 4

8-30 cm

Question 5

Describe the eggs of Toxocara vitulorum.

Answer 5

Medium, spherical, thick shell, rough surface, unembryonated, dark brown

Contain one cell.

Question 6

What happens during the life cycle of Toxocara vitulorum after oral ingestion of embryonated eggs?

Answer 6

L3 larvae migrate to various organs, including liver and lung, and remain dormant until pregnancy

Then they migrate trans-mammary to infect the calf.

Question 7

What is the pathogenesis of Toxocara vitulorum in adult cows?

Answer 7

Usually not pathogenic, but migrating larvae can cause organ damage

Adults can also suffer from nutrient deprivation.

Question 8

What is the impact of Toxocara vitulorum on calves?

Answer 8

High mortality rates

Calves are particularly vulnerable to severe effects.

Question 9

What are some clinical signs of Toxocara vitulorum infection?

Answer 9

Cough, colic pain, convulsions, movement disorders, butt paralysis, diarrhea

Question 10

What treatments are effective against Toxocara vitulorum?

Answer 10

Albendazole, Ivermectin

Question 11

What control measures can be taken to prevent Toxocara vitulorum infection?

Answer 11

Keep cows off contaminated pastures, manure removal, disinfection of stalls

Question 12

How is Toxocara vitulorum diagnosed?

Answer 12

Coprological examination

Question 13

In which geographical areas is Toxocara vitulorum most commonly found?

Answer 13

Tropical areas

Question 14

What is the significance of water buffalos in relation to Toxocara vitulorum?

Answer 14

Seen to be very susceptible to infection

Question 15

Fill in the blank: The major source of infection for calves with Toxocara vitulorum is the _______.

Answer 15

trans-mammary route

Question 16

True or False: Toxocara vitulorum causes significant pathogenic effects in adult cows.

Answer 16

False

Question 17

What is the larval migration pattern in Toxocara vitulorum after ingestion?

Answer 17

Liver-lung migration, followed by dormancy in various organs

Question 18

What happens to Toxocara vitulorum eggs after they are excreted?

Answer 18

They are excreted through the feces

Question 19

Life cycle of Toxocara vitulorum

Answer 19

• Trans-mammary route is the major source of infection.
• Oral ingestion of embryonated eggs on pasture for adult cow. L3 larvae in the intestine travel to various organs (liver-lung migration) where they stay dormant for a period of time until the cow is pregnant. Larvae then undergo transmammary migration in the cow, entering the milk, which results in a lactogenic infection in the nursing calf.
• The larva develops inside the calf until the larva matures into adult.
• The eggs are excreted through the feces.

Question 20

Epidemiology of Toxocara vitulorum

Answer 20

• Reservoir of larvae in the tissues of the cow, trans-mammary transmission can happen.
• Up to 100% of calves can be infected in endemic regions with poor control measures.
• Water buffalos seen to be very susceptible.

Question 21

Transmission of Toxocara vitulorum

Answer 21

• Somatic migration - hypobiosis of larvae
• Lactogenic - most common, no migration in calf