Animal rights groups are calling for a ban on the sale of horse meat after disturbing video emerged from a Quebec slaughterhouse showing horses being knocked unconscious before they are butchered.

One of the videos, shot with a hidden camera in Les Viandes de la Petite Nation in western Quebec, shows an agitated-looking horse standing in a small stall.

A worker from the facility near Montbello, Que. walks up to the animal, pets it briefly, then shoots it in the head with what is known as a captive bolt pistol.

The horse rears back, apparently in pain, before slumping down in the stall, unconscious.

In other videos, all shot over a period of two days, some horses are hit multiple times before they are knocked out. One is hit 11 times. In one video, a worker waves goodbye as a horse goes unconscious.

"It was basic shock and disgust," said Lisa Rowlands, who runs Refuge RR, a horse rescue farm in Alexandria, Ont., describing her reaction to the video.

"You can't have an animal that for most of its life is given medication, is given very good care, is treated with love and respect and all of a sudden say 'we're going to eat him.'"

A supervisor at Les Viandes de la Petite Nation, Stephane Giguere, defended the company in a brief phone call with CTV.

"What we do here is legal and supervised by the Canadian government. We do a very good job here," said Stephane Giguere. The company claims the footage was obtained illegally.

Alex Atamanenko, an NDP MP from B.C., wants to change the federal laws governing the industry.

Atamanenko has introduced a private member's bill to the House of Commons that would ban the transportation of horses for the purpose of importing or exporting the meat.

That would effectively shut down the horse meat industry.

"Mr. Speaker, whereas horses are ordinarily kept as pets for sporting and recreational purposes, and whereas they are not raised primarily for human consumption, and whereas horse meat products for human consumption are likely to contain prohibited substances, this bill would stop the import of horses for slaughter for human consumption," he said in the House of Commons earlier this year.

Atamanenko also said in a statement he is "sickened and disappointed" that the federal government "continues to allow this industry to abuse these animals and the regulatory system."

"This is the fourth plant to be exposed by undercover investigations indicating that an ingrained culture of abuse is still firmly in place," he said.

Atamanenko's Bill C-322 would put the brakes on an industry which doubled in size during the recent five-year ban on killing horses for meat in the U.S. That ban was lifted in mid-November.

The Canadian industry has since connected with markets in Europe and parts of Asia and is estimated to have brought in about $70 million last year alone.

In fact, the federal government provided roughly $2 million in funding last year to help expand the Quebec facility in question.

Twyla Francois of the Canadian Horse Defence Coalition -- which was sent the videos from inside the slaughterhouse -- agreed with Atamanenko that there are too few safeguards on the sale of horse meat.

"The meat is actually quite toxic, most of these horses come as ex-pets, ex-race horses," said Francois. "Nobody raises horses to be used as meat and so they're given series of drugs along their lives."

Atamanenko introduced his bill to Commons on Oct. 5 of this year. Few private members bills, particularly from opposition MPs, become law.

With a report from CTV Ottawa's Joanne Schnurr