INTESTINAL worms in dogs are very common and worm eggs are constantly present in the environment.
Working dogs are at high risk of carrying intestinal worms and contributing to their spread.
Protecting working dogs from intestinal worms is not only important for their health, but it is also an important part of protecting people as many intestinal worms have zoonotic potential (can infect people) as well as livestock.
The common intestinal worms that infect working dogs are: Tapeworm, Roundworm and Hookworm.
Tapeworm:
There are many species of tapeworm that can infect dogs.
Dogs become infected when they ingest a tapeworm infected intermediate host.
Intermediate hosts, such as cattle and sheep, become infected following ingestion of tapeworm eggs in the environment that have been excreted in the faeces of an infected dog.
In the intermediate host, larval cysts can form in muscles as well as other organs, which can reduce meat quality, resulting in economic losses for meat producers.
Clinical Signs: Normally infection with tapeworm is asymptomatic in dogs.
However, heavy worm burdens can rob the animal of nutrients, causing weight loss and diarrhoea.
Zoonotic Potential: The Hydatid Tapeworm can infect people if they ingest the tapeworm eggs.
Hydatid cysts can then form in any part of the body and can be life threatening if untreated.
Control: Even though infestation with tapeworm is normally asymptomatic in dogs, infestation contributes to contamination of the environment so control is important.
For adult dogs, treatment for most species of tapeworm is with either a broad spectrum worm tablet or specific tapeworm tablet every three months.
Puppies should be treated every fortnight from two weeks of age till 12 weeks of age, then monthly from three to six months then every three months.
It is also important to control fleas as they act as a host for the most common species of tapeworm, Dipylidium caninum.
To control the Hydatid Tapeworm adult dogs need to be treated every six weeks.
It is important to prevent hunting and scavenging in working dogs, as sheep, goats, cattle, wallabies and kangaroos can act as intermediate hosts for other species of tapeworm.
Removing carcasses and faeces from the farm and restricting the movement of working dogs when not working will help reduce the risk.
Working dogs should not be fed raw offal.
None of the monthly spot–on or oral flea control products will control tapeworm.
Round worm:
Toxocara canis is the most common roundworm species in dogs.
Dogs become infected when they ingest eggs passed in the faeces of an infected dog or ingesting an infected carrier host such as a rodent or bird.
Puppies can become infected in the womb or through the milk from mothers.
Clinical signs: Common signs in puppies include weight loss and a pot belly.
Other signs include loss of appetite, vomiting (including seeing worms in the vomit), diarrhoea, depression and can even lead to gastrointestinal blockage and death.
Zoonotic Potential: Ingestion of roundworm eggs from the environment may produce covert (hidden), ocular (eye) or visceral larva migrans.
Due to their poor hygiene compared to adults, children are more at risk.
Once ingested the larvae developing inside the egg hatch and can migrate within the body to organs such as the liver, lungs, brain and eyes.
Such migration can set up marked responses from our immune system, leading to symptoms such as abdominal pain, fever, liver enlargement and a cough.
Symptoms are often self–limiting, meaning they will resolve themselves, but infection can lead to serious complications if there is brain or heart involvement.
Larvae that migrate to the eye can lead to blindness.
Control: Bitches should be wormed prior to mating and throughout the pregnancy with a registered product that is safe for use during pregnancy.
Puppies should be treated fortnightly from two weeks of age till 12 weeks or age, then monthly from three to six months then every three months with a broad spectrum worm tablet or a monthly tablet or spot–on that controls fleas as well as roundworm.
Hookworm:
They are blood sucking worms that infect dogs and people.
Dogs are infected by ingesting larvae in the environment or by larvae penetrating the skin.
Clinical signs: Common signs include anaemia, anorexia and diarrhoea.
Zoonotic Potential: All hookworms are zoonotic and may cause cutaneous larva migrans in people.
Penetration of the larvae through the skin produce an itchy rash called 'ground itch'.
Control: Puppies should be treated every two weeks from two weeks of age till 12 weeks, then monthly from three to six months then every three months with a broad spectrum all wormer or a registered monthly tablet or spot–on product that controls fleas as well as hookworm.
In summary:
Intestinal worms in working dogs pose not only a significant risk to your dog but also your family.
Contact your local vet for more advice on the control of intestinal worms in working dogs.