Roundworms in Dogs

Roundworms are white, round-bodied worms, and can get up to 18cm long! These worms spend most of their life within the gut of dogs, feeding on intestinal contents. Roundworms reproduce by laying eggs within the intestine. These eggs are passed out with faeces, mature for up to seven weeks, and then become infectious. Dogs then ingest these infectious eggs, which hatch into larvae. Importantly, larval roundworms can travel out of the gut to a wider range of tissues, including multiple organs such as the liver and lungs, skeletal muscle and the gut wall, where they may form cysts. This allows dogs to maintain a level of infection, and bitches can pass on infections to their puppies via the placenta or milk. This infection of puppies is the most common route of infection. Sadly, toxocara can also infect humans and, while usually harmless in adults, can cause serious damage to children’s eyesight.

A roundworm infection, also called toxocariais, can be picked up by a dog in one of four ways:

1. By eating infectious eggs, in contaminated soil or faeces
2. By eating another infected animal, which can include rats or birds
3. Puppies can get roundworms through their mother's milk
4. Puppies can be born infected if their mother is infected

With so many sources of infection, and a high prevalence of toxocara infection in dogs in the UK, roundworms are a risk for all dogs. Certainly, it would be impossible to keep a dog away from all sources of infection, as this can include soil!

In a healthy, adult dog there may be no outward signs of a roundworm infestation beyond visible adult worms in the faeces or vomit. However, in severe infestation, or in dogs that are very young or have a poor immune system, you may also see:

• A pot belly
• Diarrhoea
• Weight loss, or poor growth
• Poor coat quality

With so many sources of infection, and a high prevalence of toxocara infection in dogs in the UK, roundworms are a risk for all dogs. Certainly, it would be impossible to keep a dog away from all sources of infection, as this can include soil!

In a healthy, adult dog there may be no outward signs of a roundworm infestation beyond visible adult worms in the faeces or vomit. However, in severe infestation, or in dogs that are very young or have a poor immune system, you may also see:

• A pot belly
• Diarrhoea
• Weight loss, or poor growth
• Poor coat quality

Sadly, a heavy infestation in a young puppy can even be enough to kill.

If your dog is experiencing any of these signs and you suspect that they might have worms then you should make an appointment with