Louisville-based sports-apparel firm Pearl Izumi is trying to make amends with the outraged public over a controversial running-shoe ad featuring a dead dog.

The advertisement ran in a Canadian magazine with a picture of a runner giving his dog CPR on a trail, implying the animal had a heart attack while trying to keep up with its distance-running owner.

The caption below the image said the new line of shoes “isn’t for the faint of heart.”

The company responded quickly to the negative response last week by posting an apology on Facebook that read, “We would like to sincerely apologize to everyone for the ad that ran in Canadian Running Magazine. As most of us here at Pearl Izumi are dog owners, we want you to know we would never, ever do anything to harm an animal. Please know that we have deleted the ad and removed it from all future publications.”

Pearl Izumi posted another update on its running Facebook page Friday, further apologizing and noting that the company is making a $10,000 donation to the Boulder Valley Humane Society to prove its commitment to healthy pets.

Margaret Campbell, a marketing professor at the University of Colorado at Boulder, said that the biggest mistake Pearl Izumi likely made was not testing out the ad on consumers before running it.

“Several different companies have fallen into this same trap over time,” Campbell said. “Humor is hard to get right; it is easy to offend. So, I always say go out on the street and test it on at least a few people.”