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Pet Care - Worming

Pet care advice about Worming

Broadly speaking there are two types of worm that are relevant in cats and dogs, roundworms and tapeworms. These worms spend most, but not all, of their active life in the gastrointestinal tract of their chosen host. A proportion of worms at certain life cycle stages will hibernate as small cysts in the bodies of dogs and cats. These cysts will reactivate during pregnancy and lactation.

Puppies and Kittens kitten and puppy together
Puppies and kittens should be wormed monthly with fenbendazole (panacur/ wormazole) as per manufacturers instructions. This is to control any worms that may have reached the young animal from its mother. Repeated doses are required as the worms may only be killed while in the guts, not during their migration through the young animals body. The wormers only kill the adult worms in the intestines.

Six months of age and older
After 6 months of age, dogs and cats should be wormed between two and four times a year. Cats should be wormed more frequently if they hunt and eat wildlife and less frequently if they are house cats. Dogs should be wormed more frequently if they spend time in the same areas as small children as the dog round worm, Toxocara, can very rarely cause blindness if contracted by humans.

Pregnant Bitches
Pregnant bitches should be wormed daily with fenbendazole (panacur/ wormazole) from day 40 of the pregnancy to try and reduce the flow of worm larvae from the dam to the growing pups. The wormers (anthelmintics) only kill worms that are present at the time of worming. It is a good idea to use a complete wormer such as milbemax at least once a year. Wormers should be obtained from veterinary surgeries or pharmacists as many 'over the counter products' have very limited effect.


Tapeworms can be very long worms and are made up of individual segments. The most common evidence of a tapeworm is seeing a small segment, with the appearance of a rice grain, being passed or crawling out of the animal's anus. Animals become infected with tapeworms by eating an intermediate host. Intermediate hosts include fleas, worms, snails, slugs, frogs, rodents, and birds. Tapeworms are not a particular problem in puppies and kittens.


Roundworms vary in size but are classically described as having the appearance of spaghetti or noodles. Roundworms can be contracted by eating intermediate hosts as with tapeworms, by eating grass or other vegetation with eggs on and in young animals from their mother via the placenta and milk.