Companion Animals

identification of parasitic worms in working dogs

Companion Animals

Your pets and working animals.

Companion animals include working dogs such as sheep dogs and gun dogs as well as pet cats and dogs.

All these animals are at risk from parasites, although the risk can be different for each one. Some infections may also be spread between species, including livestock and birds. Therefore you should be aware of each animal’s specific risk and tailor your parasite control programme to suit.

Two main types of parasite commonly affect companion animals. Ectoparasites that live, feed and sometimes breed on an animal, and endoparasites that live and breed inside an animal.

How we can help you

We offer a wide range services that will help you:

  • Accurately identify parasites
  • Only treat your animal when necessary
  • Accurately target treatment
  • Predict future heavy parasite burdens
  • Monitor the effectiveness of your parasite control programme

Domestic pets

The key parasites for domestic pets are:


The European Scientific Counsel for Companion Animal Parasites (ESCCAP) UK and Ireland advise that you check your pet for ticks regularly, ideally every 24 hours during tick seasons. You should remove any you find with a suitable tick removal device (for more information on how to safely remove a tick please visit

This will reduce the risk of tick-borne diseases being transmitted into the bloodstream of your pet. Important diseases in the UK include Borrelia burgdorferi (which causes Lyme Disease) and Babesia canis, which has recently become more widespread in the UK. This is particularly important for dogs that walk in countryside shared by deer or livestock, and in parts of the UK known to have a high density of ticks or outbreaks of tick-borne disease.

Tick treatments are often combined with those for fleas and roundworm, which can simplify your pet’s parasite control plan.

If your pet becomes ill following a tick bite always seek advice from your vet.


As well as being a nuisance for both animals and owners, fleas can transmit tapeworms to your pet. Eliminating flea infestations can also be a frustrating process, often taking many months. Therefore, prevention is by far the best option.

You should combine regular preventative treatment with washing your pet’s bedding and vacuuming soft furnishings and carpets (paying particular attention to areas under curtains and furniture, against skirting boards and cracks in floorboards).

Flea treatments are often combined with those for ticks and roundworm, which can simplify your pet’s parasite control plan. Fleas typically become less active during the winter months but it is important to continue treatment for other parasites even if you temporarily stop treatment for fleas.

If your pet has recently had fleas you should also consider treating it for tapeworm.


Toxocara spp. infection is very common in cats and dogs, particularly young animals, especially if they hunt. ESCCAP UK & Ireland recommends you treat your pet for roundworms regularly, although no more than once a month.

Wormers are often combined with treatments for ticks and fleas, which can simplify your pet’s parasite control plan.


Angiostrongylus vasorum has spread across the UK. Therefore, it is now recommended you consider including treatment for it in your pet’s regular parasite control programme.

Dogs that are known to swallow slugs and snails, or eat grass that may contain small slugs and snails, are at increased risk. Some areas of the UK are higher risk than others so we advise you discuss the risk with your vet.


Cats and dogs that hunt are at higher risk of contracting tapeworm through eating their prey.

Dogs with access to raw meat, offal and carcasses may also be at risk of contracting Echinococcus granulosus tapeworm. This is a dangerous parasite that animals can transmit to humans, where it causes hydatid disease.

Echinococcus granulosus is widespread in Wales, along the Welsh border and in the Western Isles of Scotland. However infections have been recorded throughout the UK. ESCCAP UK & Ireland recommends that all dogs are treated for tapeworm with a product containing praziquantel four times a year, and those living in or visiting areas where the infection is widespread and they have access to carcasses are treated every 4-6 weeks.

Working animals

Working animals may be at a higher risk of contracting parasites than domestic pets. Therefore, as well as keeping to the advice for domestic pets, owners of working dogs should also be aware of the following:

Working Dogs

When working dogs defaecate in grass runs or in a particular area of a yard, it can create an environment where whipworms and the northern hookworm, Uncinaria spp., can establish themselves. You can control this by removing faeces regularly and worming your dogs with treatments effective against hookworms and whipworms.

Dogs that hunt are also more likely to eat raw game or offal, which may increase the likelihood of tapeworm infection. They may also come into contact with rabbit fleas.

Sheep dogs

Sheep dogs are also more at risk of exposure to Neospora caninum. This parasite is particularly dangerous for cattle and sheep, causing abortion and infertility.

Infected dogs can pass the infection on to sheep and cattle, and can also suffer from paralysis and muscle atrophy. Dogs usually pick up the infection after eating carcases or infected placenta.

Preventative drugs are not proven to be an effective method of control. Therefore, you should not allow your dogs to access livestock feed stores and should keep them away from infected flocks and herds.

Another parasite that presents a high risk to livestock is Fasciola hepatica, the common liver fluke. Although dogs can host liver fluke, it does not typically cause them many problems. Dogs usually pick up the infection after eating aquatic plants or drinking water contaminated with metacercariae.

However, the parasite is much more serious for grazing ruminants, and is particularly harmful for sheep.

All dogs should be prevented from feeding on carcasses, raw meat or offal. This is particularly important in areas where Echinococcus granulosus is widespread. If your sheep dogs are likely to come into contact with fallen stock, you should treat them every 4 – 6 weeks with a product containing praziquantel.

In addition to risk from parasitic disease, Border Collies are particularly susceptible to central nervous system toxicity associated with treatments containing ivermectin. Therefore you should look for this when worming your dogs and consult your vet before you treat them.


Hounds may be fed on raw horse meat containing Echinococcus equinus cysts. Whilst this species is not zoonotic (a disease that can be transmitted to humans from animals), feeding of raw offal containing the cysts can perpetuate the infection when horses eat grass contaminated with dog faeces containing the worm eggs.

You can control this by cooking offal before feeding, regular worming with a product containing praziquantel and, where possible, ensuring that faeces are removed.


Traditionally greyhounds have access to grass runs where they can defecate. This can create an environment where whipworms and the northern hookworm, Uncinaria spp., can establish themselves. You can control this by removing faeces regularly and worming your dogs with treatments effective against hookworms and whipworms.