United States and European Union fresh pork imports threaten the disease-free New Zealand pork industry, according to industry body New Zealand Pork.
The first consignment of imported fresh pork arrived in February, and so far a total of about 275 tonnes has entered the country.
Of this, 250 tonnes comes from the US, and 25 tonnes from the European Union.
The disease which has pig farmers worried is the porcine reproductive and respiratory syndrome (PRRS) virus.
It can wreak havoc on pigs but is harmless to humans.
PRRS, which has swept worldwide since 1987, is not found in New Zealand, Australia, Sweden, Finland or Switzerland, and is also not reported in some developing countries without significant commercial pork industries.
Most major producers and exporters of pork, including the US, Canada and Denmark, have had PRRS for several years.
New Zealand Pork chairman Ian Carter said the industry was opposed to the risk of bringing in the harmful organism through fresh imports.
It was not opposed to the import of pork carcases, which were turned into ham or bacon, because the PRRS virus was destroyed during processing.
"Since January we've been asking for a testing regime for the fresh pork.
"At present the Ministry for Primary Industries (MPI) is only inspecting the imports," Carter said.
A spokeswoman for MPI said testing was not a requirement under the import health standard.
The way was opened for the pork imports in December when New Zealand Pork lost its final appeal in the Supreme Court, after a series of court cases lasting five years.
Sows affected by PRRS suffer abortions and death, while piglets are born weak.
Growing pigs are then affected by respiratory diseases, such as pneumonia.
It costs the US pork industry more than $700 million a year to combat the virus.
Dr Eric Newman, a consultant veterinarian epidemiologist, was employed by New Zealand Pork to quantify the risk of the disease entering the country. He calculated there was a risk of an incursion within 10 years.
On the other hand experts hired by the Ministry for Primary Industries (MPI) said the risk was once in 1227 years.
"There was a difference between the experts because critical information was missing. No-one has done the work on how much virus we can anticipate in an average piece of pork when it is on the plate, because we don't know how much disappears during processing," Dr Newman said.
"Some people are more risk averse than others, and that's how they reached different conclusions," he said.
Carter said New Zealand Pork was also unhappy with procedures to deal with diseased waste. He said MPI had adopted the stance that, since it was against the law to give pigs contaminated meat, people would not do it.
"That's like saying that it's against the law to drive faster than 100 km/h. The fact is, if there isn't a policeman around, people will break the limit.
"It's the same with feeding contaminated pork to pigs. Just because it's illegal doesn't mean it won't happen," he said.
Carter said New Zealand Pork was not so much worried about commercial farmers - "it's their business which is at stake" - but people on lifestyle blocks with one or two pigs.
"People on lifestyle blocks are keen on doing the right thing and think they are being good on the environment by feeding waste to livestock rather than putting it in a landfill," Carter said.
Newman said MPI had stipulated that cuts of imported fresh pork had to be 3 kilograms each, therefore "consumer ready" with little chance for waste.
"It's a novel way of dealing with the issue of waste.
" It presumes that there will be little waste from a 3kg cut, but in fact that is a large cut for the average person," Newman said.
Carter acknowledged New Zealand did not produce enough pork to satisfy the local market.
For example, pork bellies which are sought after by restaurants, are imported from Finland which does not have PRRS.
Mad Butcher chief executive Michael Morton said his stores sold imported fresh pork loin.
"There's no skin or bone on it so there's no waste, it's a premium product," Morton said.
He said he was informed by importer Smithfields that MPI officials had opened up cartons of the fresh pork, taken temperatures and sliced the pork open.
They had not done tests for PRRS because lymph nodes, where the disease is found, were not on the meat.
Morton said if New Zealand farmers could provide the equivalent product his company would sell it, but pig farmer numbers were dropping.
In 2012-13, pig numbers dropped to 298,000, down by 5 per cent on the previous year.
- Waikato Times