Burger King pledged earlier this year that by 2017, all of its pork and eggs will come from free-range animals. The fast-food chain has came under scrutiny again after a video was released by animal rights activists showing acts of abuse against cows used by Burger King. (Watch video below)

Mercy For Animals released the video which was secretly recorded at Burger King cheese supplier, Bettencourt Dairies in Murtaugh, Twin Falls County, Idaho. In the disturbing video, it documents workers punching, shocking, jumping and kicking the cows in a bid to purposefully inflict pain on the cows. In one particularly disturbing scene, a helpless cow is seen being dragged by a tractor.

Mercy For Animals said its team spent three weeks this summer recording undercover footage at Bettencourt Dairies, one of the largest in the U.S. Burger King indirectly supports the abuse by receiving cheese supplies from Bettencourt, Mercy for Animals said.

"This is blatant animal abuse that Burger King should not be supporting," Eddie Garza of Mercy for Animals said at a news conference Wednesday in Miami.

The Florida-based fast-food chain responded by noting that less than 1 percent of its cheese can be traced to the Idaho dairy.

The recording has led to criminal animal cruelty charges against three employees: including a manager. Farmworker Jose Garza's pre-trial date has been set for Tuesday October, 16. The manager Jose Acensio and the other employee, Javier Rojas-Loayza have yet to be caught.

Meanwhile, animal welfare expert, Dr. Temple Grandin - who is the subject of the widely acclaimed movie "Temple Grandin" which documents who innovative methods to reduce animal abuse and stress as they are led to the slaughter house - weighed in on the controversy.

"The abuse of the downed cow with electric prods and dragging with the tractor was horrific animal abuse. If this abusive treatment had occurred at a slaughter plant, the plant would have been shut down by the USDA. The atrocious treatment of cows at this dairy is an indicator of a total lack of management supervision," she said, according to Broward Palm Beach news.

Mercy For Animals is urging Burger King to terminate its relationship with Bettencourt Dairies and have a more zero tolerance policy when it comes to how the cattle that provide their meat and dairy are treated.

MFA is also urging Wendy's and Kraft food to stop buying products from the supplier.

Warning: Video contains graphic content