The delay by animal welfare activists in reporting calves being born in boggy mud in Southland was "disappointing", the Ministry for Primary Industries says.

Animal rights group Safe yesterday released the imagery of cows calving in winter grazing paddocks in Southland. The photos showed the animals giving birth in muddy paddocks and also of newly born calves lying in the mud.

Safe campaign manager Marianne Macdonald said the footage was taken from the roadside next to five farms in Southland between July 31 and August 8.

"It was shot by Matt Coffey and Geoff Reid, who passed it on to Safe," she said.

Safe then released the information to the MPI yesterday morning before issuing a press release and links to the photos and video.

However, yesterday the organisation confirmed it had received the footage and videos on August 10 — 17 days before reporting it to the MPI.

Evidence of calves being born in muddy winter grazing paddocks on Southland farms has outraged animal rights organisation Safe.PHOTO: MATT COFFEY AND GEOFF REID

When asked about the delay, Ms Macdonald said it was not about calling out individual farmers; it was the whole system which was broken.

It was a like a lottery trying to gain footage of farms which showed damage to the environment and the suffering of animals, she said.

"There are about two million animals in Southland and Otago in mud. These five farms are just an example.

It was up to the MPI to investigate what was happening on farms, rather than waiting for volunteers to make complaints — "complaints that don’t lead to any effective changes in these appalling practices. So if MPI were effectively monitoring what happens on farms, they would easily find it."

MPI director of compliance Gary Orr said the ministry took animal welfare very seriously and was committed to looking into every complaint it received.

It was alerted to the images and footage yesterday morning and an investigation had started, he said.

"It is disappointing MPI was not informed of this issue more than 20 days ago, when the footage was available, so that we could have acted sooner.

"We strongly encourage any member of the public who suspects a case of animal ill-treatment or cruelty to report it to the MPI animal welfare complaints hotline by telephoning 080000-83-33 so that prompt action can be taken."

Yesterday, Environment Southland also confirmed it had received no complaint in relation to the Southland farms.

New Zealand Vet Association chief veterinary officer Helen Beattie said the MPI had set up a winter grazing task force, which had produced a report setting out guidelines including occurrences which should never happen.

"Certain issues are clear-cut and change can happen over the short term. Some things should never happen and action must be taken immediately to prevent them," the report said.

Animals giving birth on mud was something that should never occur, it said.

Ms Beattie said even though cows were scanned to try to determine when they would calve, premature births could occur.

This could mean cows might deliver calves unexpectedly before farmers had a chance to move them.