The Calgary Stampede is coming under fire once again for its controversial calf-roping event, in a new ad that compares the event to abusing a baby.

The print ad was released by the Vancouver Humane Society and published in a Calgary newspaper this week.

The ad shows a three-month-old human baby, wearing a diaper and gazing into the camera, and a young calf, side by side.

The text under the images reads: "Just three months old. Would you abuse a baby to entertain a crowd?"

Speaking to CTV Calgary, Peter Fricker of the Vancouver Humane Society said the ad is appropriately critical of the "immoral" event.

"We think it's self-evident that if you chase an animal across an arena, rope it to a sudden halt at speeds up to 27 miles an hour and pick it up and throw it to the ground, it's going to experience fear pain and stress. We think that's completely immoral and inappropriate for the 21st century," Fricker said.

In the event, competitors on horseback chase down and lasso a calf, stop it dead in its tracks, then jump off their horse, flip the calf on its back and tie its legs together. The average calf used in the event is between three and six months old.

Organizers of the world's largest rodeo maintain they have taken steps to make the event more humane, such as removing the rule that stated a calf had to remain tied up and immobilized for six seconds.

“The fact of the matter is we don’t really worry too much what the Vancouver Humane Society says because of the simple fact that we go a long way to protecting animal welfare on our own,” said Doug Fraser, media relations manager for the Calgary Stampede.

“We have all sorts of programs in place to ensure that the animals are in the best shape possible,” Fraser told CTV News Channel.

Fraser cited such programs as Fitness to Compete, which has the aim of ensuring that all animals entered into the competition are in the best possible shape.

Under the program, inspectors check the animals when they arrive on the park, and horses are checked before and after the competition, according to Fraser.

“Let’s face it, these stock contractors make huge multi-million-dollar investments in these animals. I don’t think they’d want to send them into a dangerous situation,” Fraser said.

“So we are very confident in our animal care practices. We ourselves are stock contractors and we know darn well that we wouldn’t be anywhere if we didn’t help the animals.”

For the past 10 years, organizers of the Stampede have worked with the Humane Society and the SPCA to make their events, ranging from barrel-racing to chuck wagon races, more palatable to animal rights advocates.

The Vancouver Humane Society is calling for a ban on calf-roping at all rodeos across Canada and specifically wants the Calgary Stampede -- which starts Friday -- to blaze the way by dropping the event.

The Calgary Humane Society says it is also opposed to calf-roping, but is focused on working with the Stampede to improve treatment of animals at all its events, rather than advocating for a ban on calf-roping.

With a report from CTV Calgary's Stephanie Brennan