Nantwich Veterinary Group Blog

Arriving at the practice in the morning, my first patient was already awaiting me: Moss, a border collie that had just eaten a plastic bag. To prevent the plastic bag getting stuck in his bowels, we decided to make him sick. To our surprise not only did he vomit up the plastic bag with a whole lot of food, but also three slugs and a round worm!

Round worms look like small pieces of spaghetti. They live in the dog’s bowels and consume partly digested food.

 Dogs become infected by swallowing roundworm eggs, which contain infectious larvae. These larvae hatch in the stomach and small bowels and migrate to the muscle, liver and lungs. The larvae will be coughed up and swallowed again, and, back in the bowels, develop into egg-producing adults. The eggs will pass in the dog’s faeces.

Although these worms are not very harmful to adult dogs, large numbers can cause vomiting, diarrhoea and weakness.

Roundworms can be diagnosed by detecting the eggs in a microscopic examination of a faecal sample, or like in this case by finding a mature worm in the vomit.

Moss was treated with a worming tablet. This will essentially anaesthetise the worm so that it releases its grip on the host’s intestine and passes with the stool. However this treatment will not kill the immature stages or migrating larvae.

Roundworms can pose a health risk for humans, and children are particularly at risk. Prompt disposal of dog faeces is important, especially in gardens and playgrounds. The main danger is that the larvae migrate to the eye where they can cause blindness.

Pregnant bitches that have had roundworms at any time in the past will transmit them to their pups before birth, even if there are no eggs in the faeces. This is because the larvae that migrated to the muscles will have encysted in a resting phase. The hormonal changes during the pregnancy cause the larvae to migrate again, across the placenta to the puppies. The larvae can also be passed on after birth through the milk.

Almost all puppies are infected with round worms when they are born and should be wormed at regular intervals from 2 weeks of age onwards. Affected puppies can lose weight and have a pot-bellied appearance.

After 6 months of age, all dogs should be wormed 3 to 4 times a year.