Dog owners in Newfoundland and Labrador should check their pets for deer ticks — small insects that can cause Lyme disease — when they return from walks in the woods or deep grass, the province's chief veterinarian warns. 

A Corner Brook dog was diagnosed with the disease in June after a deer tick was found on the animal, Hugh Whitney said Thursday.

It's the second confirmed case of Lyme disease in a dog in Newfoundland and Labrador. The first was in 2004 and was also found on the island's west coast.

The deer ticks live in tall grass or on the woodland floor. If a Lyme-infected tick bites, it can inject bacteria that cause serious illness, though it's rarely fatal.

Whitney said dog owners should be on the lookout for the small bugs, which can be difficult to spot.

"They drink blood, so they can swell up to a decent size when they're engorged," said Whitney.

"They may look like a wart or something like that on the skin, and they tend to be in areas where the dog would not be able to get easy access: the back of the neck, behind their ears, areas where they don't see them and can't lick them to get rid of them."

Whitney said the dog that contracted Lyme disease is being treated with antibiotics.

Dogs with the disease may exhibit lameness, loss of appetite, fever and loss of energy. They usually respond well to treatment.

People can also contract Lyme disease, but Whitney said there have been no reported cases in the province yet.