It's hell for pigs in one of the largest pork producers in U.S. - Iowa Select Farms in Kamrar, Iowa. A new undercover investigation conducted by Mercy For Animals, an animal rights group based in Chicago, revealed that at this factory firm mother sows and their piglets are forced to suffer brutal abuse and lives of unrelenting confinement and misery.

The nonprofit animal rights group has released a hidden camera video that shows horrific images of throwing piglets into concrete flooring, tail-removal and piglet castration without benefit of anesthetic and confined conditions of fully grown sows within gestation crates.

Gaining access as employees, our investigators go in as eyes and ears for the public, Nathan Runkle, executive director of Chicago-based Mercy for Animals, told abc News. They give their real names and real social security numbers and they shoot the video with a small undercover camera. Part of our message is there is not a single federal law that provides protection to factory animals. What we need are stricter, stronger laws, Runkle said.

Dr. Jonathan Balcombe, a world-renowned animal behaviorist, said, This video depicts scenes of unbearable suffering and inexcusable neglect. ... This farm should be closed down at once.

Veterinarian Dr. Armaiti May also denounced the operation. I was greatly disturbed and appalled to watch footage of such horrifying cruelty and neglect towards pigs, May say.

May further recommended that group housing be instituted which allows enough space for pigs to turn around and extend their limbs without touching the sides of the enclosures or each other. All surgical procedures including castrations should be done only with the pigs anesthetized and using sterile technique.

Gestation craters have already been banned in the entire European Union, New Zealand, and seven states in the U.S. including Florida, Arizona, Oregon, Colorado, California, Maine and Michigan.

Iowa Select Farms, the fourth largest pork producer in the U.S, supplies pork to JBS Swift, which, in turn, sells products to some of the biggest retailers in the nation such as Costco, Safeway and Kroger, abc News reported.

Here is the shocking video and some screenshots:

Piglets

Piglets are kicked by an employee. Source: YouTube/screenshots
Mother

Mother sows are confined inside tiny cages. Source: YouTube/screenshots
An

An employee is cutting the tail of a piglet without giving any pain relief. Source: YouTube/screenshots