Shamed dairy farmer Allan Crafar says he will appeal against recent convictions for "dirty dairying" practices, and although supporters have engaged a new lawyer for him, he will defend himself in court.

Crafar, spokesman for New Zealand's largest family-owned dairy business, Crafar Farms, which was put into receivership last week by its banks, was clearly under enormous stress when the Business Herald contacted him. But he vowed to "fight my own case" as serious new animal welfare issues fuel the crisis enveloping the family.

Ministry of Agriculture inspectors, under orders from Minister David Carter to visit all 22 Crafar farms after scores of calves died through neglect on one of the group's largest properties in the King Country, have reported underweight cows, overstocking, inadequate feed and lack of shelter for calves.

Receiver Michael Stiassny of KordaMentha has said not all the animal welfare issues were the fault of the Crafar family as some animals were owned by sharemilkers.

Reporoa-based Crafar said friends were encouraging him to accept a new Hamilton lawyer they had found, but he would need at least $35,000 and so would represent himself in the appeal.

He said the receivers had at least 10 people "on the job" in his business. Crafar Farms has had several convictions for environmental lapses and has been in the spotlight over animal welfare issues in the past. But extreme weather - drought in 2007-08 and unseasonal recent snow on the Central North Island Plateau, where many of the Crafar farms are - combined with debt-fuelled expansion and plunging milk earnings to result in a full-blown crisis across the business.

Westpac, Rabobank and PGG Wrightson Finance called in the receivers after Crafar Farms breached covenants on its loans, owing around $200 million.

Crafar's dairy company Fonterra said it had worked with the family for two years on problems. "We have been involved in specific issues around milk quality and the environment in particular," said Tim Deane, general manager shareholder and supply services.

"If you go back and look at the prosecutions for non-compliance, he did fix them and spent a heap of money fixing them. In our experience when you do intervene, he does fix it. But in this case we didn't know about it [calf deaths]. We didn't pick it up. It's impossible to know everything that is happening on 11,000 farms."

Deane said a lesson had been learned from the Crafar crisis.

Fonterra had robust systems and specialists to spot problems and help farmers deal with them. So did MAF, industry-good agency DairyNZ and Federated Farmers, which had also been involved recently at Crafar farms.

"What we could do a little better is co-ordinate our efforts more. None of us has perfect information but if you combined it all I'm sure we would pick up things that otherwise might be missed."

Fonterra was still collecting milk from Crafar farms, he said. The industry heavyweight reserves the right to suspend a farmer's milk collection over significant food safety and environment issues.

"There is a very rapid action plan taking place to get problem areas sorted fast. If we weren't picking up milk we would end up with an environmental disaster," Deane said.

"We are comfortable that the quality of milk is good, and we are also comfortable that MAF and the receivers are addressing the management issues very quickly, so on that basis we are picking up milk."

The Crafar case risked damaging New Zealand dairying's reputation. "It is impossible for me to say absolutely there are not other problems on Fonterra's 11,000 dairy farms, but I would strongly argue the Crafar case is the exception."

Fonterra had specialist teams dedicated to identifying and responding to on-farm food safety, animal welfare and environmental problems and annually assessed every dairy farm shed and the area within a 45-metre radius, Deane said. It also did surprise inspections if it suspected identified problems were not being addressed by the farmer.

Fonterra, MAF, DairyNZ and industry educator Ag ITO work on developing and publishing animal welfare education material, he said, and Fonterra and DairyNZ had just finished workshops on farming in tough times.