Animal rights activists filled a Burlington, Ont., court while others stood vigil outside as the trial began for a woman who gave water to pigs in a sweltering truck on their way to slaughter.

Anita Krajnc of Toronto is charged with mischief and faces jail time or a maximum $5,000 fine for providing water through the narrow openings of a metal trailer to the pigs as they were headed to Fearman's Pork Inc. in Burlington on June 22, 2015.

Krajnc, 49, is part of the group Toronto Pig Save, which regularly holds vigils outside the pork processing plant.

Krajnc has said the pigs were overheated and severely dehydrated. There was a tense confrontation with the truck driver, Jeffrey Veldjesgraaf, which Krajnc's group recorded.

"These are not humans, you dumb frickin' broad," Veldjesgraaf says in the video.

The next day, pork farmer Eric Van Boekel of Mount Elgin, Ont., contacted police. Officers investigated and charged Krajnc with mischief for pouring an "unknown liquid" into the trailer.

A video of the incident was played in court on Wednesday, as footage of the panting pigs left some of the animal rights activists tearful.

Veldjesgraaf, the Crown's first witness, said his was transporting 190 pigs from Van Boekel's hog farm that day, a load worth around $45,000. They weren't given any water during their 110-kilometre trip, which took about an hour and a half. They had some water as soon as they reached Fearman's, he said.

He said he regularly hauls pigs aged four to six months, which drew gasps from the animal activists in the room. On warmer days, he reduces his load to around 160 pigs.

Anita Krajnc gives pigs water near a slaughterhouse in Burlington, Ont. (Elli Garlin)

Veldjesgraaf said his main concern was over what was in the water that Krajnc's group gave the pigs, and whether it might contaminate the livestock. But he also agreed, under questioning by defence lawyer James Silver, that he had said to police that Krajnc and Toronto Pig Save had to be stopped because they were "messing with our livelihood."

Crown Attorney Harutyun Apel also called Van Boekel, who said he transports about 110,000 pigs each year to Fearman's for his contract with Sofina Foods. Van Boekel is expected to finish his testimony Thursday morning.

Silver and Krajnc's other lawyer, Gary Grill, intend to call Krajnc to testify, as well as Armaiti May, an expert in animal welfare and a member of the Humane Society Veterinary Medical Association, who will testify about whether the pigs in the video are in distress.

They also plan to introduce virtual reality video for Justice David Harris that depicts the inside of a slaughterhouse.

​The trial resumes in the Ontario Court of Justice in Burlington on Thursday. Dates are also scheduled for Oct. 3 in Burlington, Nov. 1 in Milton, Ont., and Nov. 10 in Burlington.

CBC Hamilton's Samantha Craggs is reporting live from the courtroom, and you can follow her coverage in the box below, alongside curated comments as interest in the trial grows.

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