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Ticks in Ontario

By March 2, 2017 Uncategorized

The most common tick species seen in Ontario are the American Dog Tick and the Deer Tick (Black legged tick).   Ticks can carry blood borne diseases such as Ehrlichia, Anaplasma and most commonly Lyme Disease (transmitted by the Deer Tick).  Tick populations are on the rise in both numbers and geographic distribution meaning the risk of tick borne disease is increasing.

Ticks feed on blood and can take around 5-6 hours to attach firmly to a pet and up to 10 days to fully engorge when feeding.  Unfortunately, it can take as little as 24-48 hours after attachment for a tick to transmit disease to the pet making tick preventatives key in preventing tick borne disease.  After feeding, a female tick can lay up to 8000 eggs per day.  Ticks can take up to two years to complete their life cycles but milder winters can allow adults to breed through winter months.

When and Where Are Ticks Active

Ticks are most active in the spring and fall from March-June and September-November.  However, with milder winters they can be active as early as February and as late as December.  They are active at temperatures as low as 4 degrees Celsius and can survive over winter.  Ticks prefer damp humid environments and especially wooded or grassy areas.  Precaution should be used when walking on trails, through leaf litter or near shrubs.

Lyme Disease (Borrelia burgdorferi)

Lyme disease is transmitted by deer ticks and can affect both dogs and people.  Lyme disease can be transmitted to cats but is very rare as cats are such fastidious groomers.  It can take as little as 24-48 hours after a tick attaches for it to transmit Lyme disease to the pet.  Deer ticks become infected after feeding on animals such as deer, who are carrying the disease, then transmit it to the pet via the bloodstream while feeding.  12% of deer ticks carry Lyme, but in Lyme endemic areas (lake Ontario, Long Point etc) up to 60% of deer ticks carry Lyme disease.  95% of dogs infected with Lyme disease will not show symptoms, making blood testing after tick exposure very important.  It takes up to 6 weeks after tick exposure for a dog to test positive with blood work.  For the 5% of dogs that do show symptoms, the effects may be permanent.  Signs of Lyme disease include: lethargy, inappetence, lameness, kidney failure and nervous system side effects.  The amount of time that a tick has been attached and fed on a dog determines the risk of contracting the disease: Less than 24 hours =  negligible risk,  24-48 = questionable risk, over 48 hours = significant risk.

Tick Prevention Option for Your Dog

Feel free to call us to discuss various options for tick prevention for your pet!  March is an ideal time to start on tick prevention before ticks emerge.  There are oral and topical tick and flea preventatives that kill ticks and fleas quickly.  With any tick preventative, speed of kill is important in preventing disease transmission.

I Found A Tick On My Pet, Now What?

If you have found a tick in your pet it is important to remove the tick as soon as possible to help decrease the risk of disease transmission.  Ticks can be removed with tick twisters, see link for demo ( ).  If you are unable to remove the tick or are uncomfortable doing so  we can remove the tick for you here at the clinic.  If you have successfully removed the tick, you can bring it to the clinic and we can identify the species of tick to determine whether Lyme disease transmission is a potential risk.  Note: Please bring the tick as is in a pill bottle or plastic bag for identification (Do Not Squish the tick or place in any liquids).  If a deer tick is found attached to your pet, we recommend blood testing in 6 weeks to be sure your pet was not exposed to Lyme disease.


For more information on ticks visit:

For information on the distribution of tick-borne infections in dogs in Ontario visit: 

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