The video, filmed by an investigator working with the group Mercy for Animals Canada, appears to show agitated pigs with open sores in tiny cages, adult animals being euthanized using bolt guns in the head and piglets being euthanized by slamming them against the floor.
"The extreme cruelty documented at this factory farm would horrify most Canadians, but it is actually considered standard industry practice," said Kimberly Carroll, with Mercy for Animals Canada.
"Pigs are every bit as capable of experiencing pain and suffering as our beloved cats and dogs at home, and they deserve the same protection from abuse."
But people in the industry say most of what is seen in the video is not cruelty or abuse.
An Animal Care Review Panel, made up of a University of Manitoba animal sciences professor, an Ontario Veterinary College professor and a research scientist, said the images can be disturbing to watch, particularly the scenes with the piglets, but they said it's a humane way to euthanize them.
"The practices they were using were fine," said Jennifer Brown, a research scientist at the Prairie Swine Centre. "We should be more concerned when euthanasia does not occur in a timely fashion and piglets suffer needlessly."
The panel — set up by a U.S.-based organization representing farmers, food processors and retailers — said a few of the practices in the video appear to be improper, such as when a worker appears to swing a piglet into a metal post to euthanize it.
Sores and injuries are to be expected in an animal population, the panel said, noting the video didn't show how quickly the wounds were treated.
Another scene appears to show a pig squealing as it is being castrated, but Laurie Connor, the head of the department of animal science at the University of Manitoba, said in the panel's report that the pig seems to be squealing "just as much because it is being held upside down or because it is being restrained."
The industry is looking at how to make castration less painful, but Connor said the worker in the video appeared to carry out the process well and quickly.
Mercy for Animals Canada is calling on major grocery chains to stop carrying meat from producers who use gestation crates — tiny stalls in which sows spend most of their lives.
Dave Wilkes, senior vice-president of the Retail Council of Canada's grocery division said stakeholders are in the process of developing a code of practice for the care and handling of pigs, and issues in the video such as gestation crates are being reviewed.
Florian Possberg, a hog producer in Humboldt, Sask., said when he began his business 37 years ago the sows were in group pens, but they were "quite aggressive," he said. The meeker ones would not get enough to eat at feeding time and would sometimes be attacked, Possberg said.
The gestation crates restrict the sows' movement so their waste stays at one end and doesn't get mixed in with their feed, but the code of practice review is looking at how to give pigs more freedom of movement, he said.
Parts of the video are "troubling" to watch, especially the piglets being euthanized, but it's done to be humane, he said.
"We're not cruel people," Possberg said. "We do the very best we can for our animals. This video just portrays us in the light of being callous and cruel to our animals and that's just not the case."
The video was released after an investigator working with Mercy for Animals Canada got a job at a Puratone Corp. farm in Arborg, Man., and spent about 10 weeks filming with a hidden camera.
The group sent its footage to the office of Manitoba's chief veterinarian, which has said it will be reviewing the video.
The advocacy group said meat from the plant is purchased by Sobeys (TSX:SBY), Loblaws (TSX:L), Metro (TSX:MRU.A), and Walmart Canada. Wilkes, speaking on behalf of the retailers, said when things go wrong immediate action must be taken.
"Our members and everybody that works with hogs must treat them with respect and compassion," he said.
"As an industry right throughout the supply chain we have zero tolerance for animal abuse."
Puratone CEO Ray Hildebrand has said in a statement that the company is "disturbed" by the images, which he added do not reflect its animal care rules.
Hildebrand has said an investigation is underway and that "corrective actions" will be taken as a result of the video.
Maple Leaf Foods (TSX:MFI), which entered into an agreement last month to acquire Puratone, released a statement saying the treatment in the video is "disturbing" and not accepted industry practice.
"We will conduct a thorough audit of Puratone's animal welfare practices," Maple Leaf said. "Our requirements meet or exceed industry and regulatory standards and must be strictly followed. We have a zero tolerance policy for animal abuse of any kind."