A video showing the mistreatment of bobby calves was given to the Ministry of Primary Industries by the animal welfare group Farmwatch.
Ministry says probe over alleged mistreatment started before TV exposure.
The Ministry for Primary Industries (MPI) says it had started an investigation into the alleged mistreatment of bobby calves well before the issue came to light in a television programme over the weekend.
The footage shown in the programme was part of extensive footage given to the ministry by the animal welfare group Farmwatch on September 14. Animal welfare officers reviewed the footage and immediately began an investigation, the ministry said.
MPI deputy director general regulation and assurance Scott Gallacher said the nature of the footage aired - which showed calves being kicked and clubbed to death - was unacceptable. "Anybody seeing this type of abuse would be appalled. We share that view," Gallacher said.
The company that featured in the TV programme was Down Cow, a small pet-food slaughter facility which, according to its website, specialises in beef, sheep, horse, goat and veal.
The ministry said there were clear laws and guidelines for how animals should be treated. MPI said it was not acceptable to throw, kick or hit animals. Using blunt force to euthanase bobby calves is unlawful, except in emergency situations.
MPI gets about 700 animal welfare complaints a year and follows them all up. The ministry said it had a strong record of successful animal welfare prosecutions.
Petfood Manufacturers Association secretary Richard Brake confirmed Down Cow was a member. Big multinational companies such as Heinz are also members.
"It's pretty disturbing and you wonder about the humanity of some people," Brake said.
The association's members were licensed by MPI and were regularly audited by the ministry, he said.
"The association is not a regulatory body but we certainly don't condone behaviour like that from our own members," Brake said. "That few minutes of footage was pretty horrific.
"We are right behind MPI and we will give them every assistance that they need."
It is estimated about 2 per cent of New Zealand's bobby calves end up as pet food.
John Darroch, an investigator and photographer for Farmwatch, said there had been a mixed response to the footage. He said some farmers were "indignant and unhappy" because they felt it portrayed them in a poor light, but feedback from members of the public had been positive.
Federated Farmers director and Dairy Industry Group chairman Andrew Hoggard said the footage was "not how that process occurs", adding that the actions of a few could have damaging consequences for the industry.
"The reaction so far has been from fellow farmers and they are all disgusted by the footage," Hoggard said.
"The disgust was mainly around how the calves were treated but also that these cowboys can potentially put the rest of our livelihoods at risk through their poor actions and callous treatment."
Dairy NZ chief executive Tim Mackle says the abuse of bobby calves was not as widespread as the animal welfare group Farmwatch maintained, but conceded farmers still had work to do in the area of animal welfare.
Mackle said he was "appalled" at the contents of the TV programme which showed bobby calves being thrown into trucks, and footage of animals being beaten and clubbed to death at a pet food processing plant.
"Farmers, like me, have reacted with disgust," he said. "A fair bit of the footage was appalling.
"At the same time, we would argue strongly that it [animal abuse] is not as widespread as Farmwatch are asserting," he said.
"We know that we have got an issue, and that clearly there are some things that must be fixed," Mackle said. "We need to be talking to the transport sector and to the meat industry about how we can work together to uphold our reputation, which is very good internationally, but also to look after animals."
Surveys by DairyNZ, a farmer-funded industry group, showed 95 per cent of farmers were compliant with the animal welfare code.
"That's not high enough and we need to keep lifting that," he said.
One industry source said there was a regulatory loop hole between the requirements for pet food processors, which are subject only to periodic supervision from the Ministry for Primary Industries, and export-grade abattoirs, which require full-time veterinary supervision.
Not talking
• The company at the centre of the bobby calf abuse story at the weekend was Down Cow, which is based at Te Kauwhata, near Huntly.
• Down Cow's website says it is a pet-food slaughter facility, specialising in processing beef, sheep, horse, goat and veal.
• Down Cow is a member of the New Zealand Petfood Manufacturers Association.