Parasites in Dogs

Controlling Intestinal Worms, Heart Worms, Fleas and Ticks written by Dr Claire Stevens

Dog are vulnerable to infestation by several types of parasites, including intestinal worms, heartworms, fleas and ticks, which can negatively impact their health and well-being if left unattended.

Intestinal Worms

Since puppies and kittens are most susceptible to intestinal worm infestations, deworming is probably the first health care issue a pet owner will need to attend to when after welcoming a new puppy into the home.  Intestinal worms are internal parasites that live within a dog’s intestines. Their size can vary from small to relatively large (reaching a length of up to 18 centimetres). No matter whether they are large or small, all intestinal worms negatively impact a dog’s health, and if left untreated can prove deadly. Intestinal worm infections are not limited to dogs; most animal species, including birds, cats, fish, horses, rabbits, reptiles, and humans, can become infested with worms.

In Australia, the most common intestinal worms affecting pets include:

• Tapeworm
• Roundworm
• Hookworm
• Whipworm

If your dog has a severe worm infestation, it may struggle to maintain weight and a healthy coat. In certain cases, a heavy burden of worms can cause a dog to vomit or suffer from diarrhoea, and can sometimes even cause anaemia (where your dog will have a low red blood cell count). If left untreated, a severe intestinal worm burden can be fatal.

Since worms tend to have complex life-cycles, including a period where they develop outside the dog’s body, it is important to understand the lifecycle of the specific worm you are dealing with when implementing a deworming program. For example, some tapeworms complete part of their lifecycle inside fleas, so it is important to also control fleas if you wish to control tapeworms.

It is vitally important to deworm your pets regularly to reduce the likelihood of infection and reinfection from worms dispersed into the environment in your pet’s faeces. There are many different types of deworming treatments available, which depending on the treatment, can target specific worms or a broad range of worms. Deworming treatments are typically available in various forms, including tablets, chews, or spot-on treatments that are absorbed by the skin. However, because dogs can often become re-infected, especially if their environment is heavily contaminated with worms, it is important to repeat the treatment periodically. Another good reason for regular deworming it to protect your family’s health, as children are particularly vulnerable to becoming infected with worms carried by their pets.

Tips for preventing worms in dogs:

• Get your veterinarian to draw up a regular deworming schedule for your pet and follow it diligently
• Keep your pet’s environment hygienic, cleaning up your pet’s waste regularly
• Promptly pick up pet faeces from lawns, sandpits and other areas where children play
• Encourage your children to wash their hands after playing in the sand or with their pet/s, and before eating
• Don’t let children play in soil that you suspect could be contaminated with worms
• Always pick up and dispose of your dog’s waste when walking/playing in public parks or playgrounds

Heart worms

Dirofilaria immitis, commonly known as heart-worm, is an internal parasite spread by mosquitoes that can potentially be deadly to pets. Heart-worms have a complex lifecycle, with part of the lifecycle occurring inside a mosquito before the final stage of maturation that results in an adult worm infecting a dog or cat’s heart, leading to symptoms indicating heart failure, such as lethargy, reluctant to exercise, coughing, and ultimately even death.

While heartworm is common throughout Australia, the good news is that it can easily be prevented with a range of treatment options, including an annual injection that can be administered by your veterinarian. It is advisable to consult with your veterinarian who can advise you on the best heartworm prevention program for your pet.

Fleas

Fleas are external parasites that bite into the skin of your pet to feed on their blood. Flea infestations can not only cause skin irritations in dogs, they can lead to worm infestations too. They are more prevalent in the warm summer months, but can also occur in homes that are heated during winter. The lifecycle of the flea is such that only a small part of its adult life is spent on your pet. Eggs are laid in the environment, where they hatch into larvae that can survive for a year. It is therefore important that you not only apply flea treatment directly to your pet, but that you also consider the environment to prevent re-infestation. Regularly vacuum and clean carpets, floors and wooden skirting boards, and wash your dog’s bedding in the washing machine on the hottest cycle. Consult with your vet, who can recommend the best flea treatment product/s to control fleas on your dog, as well as to manage fleas in your pet’s environment if necessary.

Ticks

Ticks are small external insect parasites belonging to the Arachnida family that measure about 3-5 mm in length. There are several different species of tick in Australia, including the brown dog tick, bush tick and cattle tick, but the species that pose the greatest risk to pets is the paralysis tick (Ixodes holocyclus), which occurs from Victoria to North Queensland. A bite from a paralysis tick can cause your dog to become gravely ill, and sadly can be fatal. The most obvious symptom is paralysis in the hind limbs; unsteady on feet, with a staggering walk; a dry cough or change in your pooches’ bark. If you notice any of these symptoms look for ticks on your dog and seek advice from your veterinarian. Your vet will be able to advise you on the most effective tick control strategy to keep your dog free of ticks.

Both internal and external parasites can be extremely harmful to your pet’s health. As with most things, prevention is better than cure. Ask your vet to recommend a regular parasite control program to ensure your pet is kept free of these potentially deadly pests.