BOSTON -- A disturbing video obtained by Team 5 Investigates from the animal rights group Mercy for Animals shows multiple incidents of mishandling of pigs at one of the nation’s largest pig farms.

NewsCenter 5’s Sean Kelly reported on Monday that some of the local grocery stores that purchase pork products from the farm are concerned enough to monitor the situation.

An undercover investigator with Mercy for Animals took hidden camera footage earlier this year at a large pig breeding farm in central Pennsylvania owned by Country View Family Farms. Some of the undercover footage shows piglets being grabbed by their ears and legs and then tossed around like footballs from worker to worker.

"It can cause severe damage to the animals," said Daniel Hauff, director of investigations for Mercy for Animals.

The rest of the video shows practices that veterinary experts tell Team 5 are far more painful. Some of the video is so disturbing Team 5 decided not to show it.

The videotape shows pigs being branded with tattoos ,as well as injured and runt piglets being euthanized in carbon dioxide gas chambers for hours. Although the practice is standard throughout the industry, Mercy for Animals told Team 5 the procedure did not work and caused baby pigs to suffer unnecessarily.

The pork is sold under the brand name Hatfield’s at stores all over New England, including Hannaford, Shaws and Stop and Shop.

“If the public saw how animals are actually treated on the farm, in the factory farm settings, then they would take a stand against it,” said Hauff.

The undercover investigator for Mercy for Animals also saw piglets being castrated by bare-handed workers using dull knives and scissors.

Mother pigs could barely move at all in gestation crates that are too small. The crates are banned in Europe, but in the United States, they’re industry standard.

“There are spots that there are wounds on the side of the pig and she can’t get away from it because the wound comes from a bar sticking right into her crate,” said Hauff.

Country View Family Farm's Veterinarian Dr. Jessica Clark told Team 5 that “providing excellent care of our hogs is a top priority because we have an ethical obligation to do so.”

Clark went on to say that the farm “cannot and will not condone mishandling of our farm animals and corrective measures have already been taken place.”

Team 5 Investigates has learned there are no federal laws requiring the USDA to inspect farms where animals are raised for slaughter, and most states exempt farm animals from anti-cruelty laws.

“The experts agree that the conditions at this facility, they’re horrendous,” said Hauff.

A representative for Stop and Shop said the company has asked the farm to take corrective steps and told Team 5 that the store will monitor the situation. A representative for Shaws said it will do the same.

But a representative for Hannaford’s didn’t respond to NewsCenter 5's request for a comment.

None of the stores would tell Team 5 if they’ll stop buying pork products from this facility.