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Worming your Pet

Intestinal Parasites and Their Prevention

Nematodes (roundworms):


Roundworms are common in dogs and cats. Infection can either be passed down to puppies and kittens by their mother, or the eggs can be ingested. Once inside the intestines, the eggs hatch and grow into long white worms (up to 10cm long). In young puppies and kittens, common clinical signs include diarrhoea, failure to thrive, a poor hair coat and a "pot-bellied" appearance. Vomiting can occur when the roundworms migrate to the stomach.

Some species of roundworm can be transmitted to humans. This is only done by ingesting eggs from the environment, so children are more likely to be infected. This is why strict and regular worming treatment for your dog or cat is essential to prevent eggs being released into the environment, as well as good personal hygiene.



Lungworm (Angiostrongylus vasorum) infects dogs when they eat slugs, snails or frogs that are carrying the worm. When a dog is infected the adult worms live and reproduce in the heart and blood vessels of the lung. They lay eggs which hatch to larvae, which are then coughed up and swallowed. They pass through the dog’s digestive tract and out in its faeces. Slugs and snails are infected by ingesting (eating) the larvae which have contaminated the environment.

Some dogs develop signs of coughing, reduced exercise tolerance or breathlessness. These signs are associated with the presence of the worms in the heart and large blood vessels and the damage done to the lungs as the larvae work their way out. Some dogs, however, do not show these signs but develop even more worrying problems. The presence of lungworm can lead to poor blood clotting, which means that these unfortunate dogs sometimes present with bleeding problems. Neurological (nervous) signs such as seizures (fits) and back pain can also be seen. If left untreated these problems can be life threatening.

Once infected, it can be difficult to treat and may be fatal. This is why monthly treatment with a licensed worming product, such as Advocat, is recommended to prevent infections occurring in the first place.



These worms live in the small intestine of dogs and cats and are voracious blood suckers. This can result in life-threatening anaemia (low red blood cell count).



These worms are also in the roundworm family, and mostly affect dogs. Fortunately, they aren't found in the UK but are present in continental Europe. The parasite is transmitted via mosquitoes, enter the bloodstream and manifest in the heart. They can cause a range of clinical signs including weight loss, lethargy, coughing and more severe conditions involving the heart. Sometimes the infestation is so severe, the worms need to be removed surgically!


Cestodes (tapeworm):

There are two important groups of tapeworm.

Dipylids: These affect dogs and cats and are transmitted by fleas. They cause mild signs including diarrhoea. These worms have segments containing eggs which break off and are passed along with faeces.

Taenids: Some of these species involve dogs and foxes, and can also be transmitted by fleas. They can form cysts in the organs of their host, such as in the liver. One species (Echinococus granulosus granulosus) is not present in the UK, so worming medication is compulsory before entering the country


Please speak to one of our team for more advice about preventative treatment for parasites, or book a consult with one of our vets.