The tick population in Ontario has been growing and is expected to exponentially grow over the next few years as a result of climate change. Ticks travel by clinging to birds and deer. There are many species of ticks that live in Ontario. The American dog tick and the blacklegged or deer tick are the ticks most likely to be acquired by dogs; however, other ticks may be detected, particularly on animals that travel. Every spring there is a “bloom” or increase in tick numbers. Ticks arrive in Ontario on migrating birds, and some ticks hibernate over winter and emerge to feed in the spring. There is also a fall bloom.
Ticks & Diseases
Ticks can carry several diseases which can infect people and dogs. In Ontario, the more common diseases include Lyme disease and Anaplasmosis. Lyme disease and Anaplasmosis are spread by the bite of blacklegged ticks. Blacklegged ticks can be found sporadically throughout the province. They are typically small when unfed (1 – 5 mm in length) and all active stages feed on blood.
Ticks usually come in contact with people or animals by positioning themselves on tall grass and bushes. They may take several hours to find a suitable place on the host to feed. Most tick bites are painless so your pet will not feel the tick’s presence. Dogs can become infected when an infected tick has been feeding on them for at least 2 days. The tick itself becomes infected by feeding on infected mice, birds, deer, and other animals. Eighty percent of the ticks submitted for identification from canine patients of Nottawasaga Valley Veterinary Hospital were the blacklegged tick.
Direct transmission of Lyme disease from one dog to another has not been reported, even when infected and uninfected dogs have lived together for long periods. Transmission of Lyme disease from dogs to people has not been reported.
Up to 90% of dogs infected with Lyme disease do not show any signs of illness. In dogs that get sick, the signs may be vague and may not appear for two to five months after tick exposure. The most common clinical sign is lameness, but a small percentage of dogs develop severe, life-threatening kidney disease. Lyme disease, once diagnosed, can be treated with a variety of antibiotics.
Anaplasmosis is much less common than Lyme disease and it may cause lethargy, inappetence, fever and a reduction in platelets, which are required for the normal clotting of blood.
Prevention and Yearly Screening
Tick prevention and regular screening tests are paramount in preventing illness in your dog. There are a variety of products available in topical preparations or in chewable tablet form which kill ticks on dogs. There is also a vaccine available for at risk dogs.
Yearly screening with the Idexx 4Dx test allows us to detect dogs that have been exposed to ticks carrying Lyme disease, Anaplasmosis and Ehrlichiosis before illness occurs. Identifying exposed dogs allows us to initiate further tests and formulate a treatment plan.
Tick preventive products should be started as early as April and should be used into November. The greatest tick activity is seen in April, May, June, September, October and November. Ticks survive in cooler weather and are active at 4 degrees Celsius and above.
For more information on tick prevention or to book your dog for a screening test, call us at 705-434-2226.