John Dalziell on his Tinui farm in 2012. PHOTO/FILE
As the threat of Mycoplasma bovis lingers in the region, many Wairarapa farmers know from past experience all about the stress of eradicating a cattle disease. BECKIE WILSON looks back nearly 30 years with farmers who lived through bovine tuberculosis [TB] eradication.
For cattle farmers, the threat of bovine tuberculosis [TB], and now and Mycoplasma bovis, is no doubt one of the biggest stresses in their farming lives.
The two diseases are devastating to herds, the cost of eradication is high, and the impact on farmers’ profitability and well-being is severe.
These days, Wairarapa is considered a “low risk” area for TB, according to the TB Free programme, but that has not always been the case.
TB is most commonly found in cattle and deer as small lesions in the lymph nodes of the chest, and is spread by possums and ferrets.
While the disease was likely brought into the country in the late 1800s it was not known that possums were spreading the disease to cattle until the early 1970s.
By then, all cattle herds across the country were under regular TB testing, and by the 1980s the disease had been effectively eradicated from many cattle herds across the country.
But it was a different story for Wairarapa, where the test and slaughter approach was not working and it had become a major cause of livestock infection.
Masterton district councillor John Dalziell wore two hats during the TB eradication programme: as chairman of the Animal Health Board when elected in 2001, and as a sheep and beef farmer
While effects of the two diseases vary, the impact on farmers is much the same, he said.
The TB eradication process was an $80m-a-year programme involving a slaughter levy on all cattle and deer from farmers, and a contribution from council rates and the government, he said.
The Animal Health Board was formed in 1993 and was charged with the eradication of TB.
Effective disease management has led to a drop in infected herd numbers from 1700 nationally in the mid-1990s to 43 in 2016.
A key difference between the two diseases is the ability to identify the source.
“If you look at TB, once you killed the possums the disease risk reduced substantially, but with M.bovis, you have got to kill all cattle, so that’s a really distinct difference,” Dalziell said.
“It’s extremely stressful for farmers.”
With TB, only animals that test positive must be killed.
But Dalziell said at the height of TB, the culling of animals, coupled with the regulations set by the AHB to stop the spread, meant Wairarapa farmer’s profitability took a hit.
Selling restrictions were put in place for farmers who had infected herds.
There were various testing programmes depending on the level of risk for each area.
“Like in Wairarapa, which was a high-risk area, everyone would have been on annual tests, but infected herds were twice yearly.”
Central Plateau and the West Coast of the South Island were also high-risk areas.
Just as with M.bovis, some sceptics argued against the costly eradication programme that began in the early 1990s, he said.
While it took some time for the number of infected herds to reduce, many farmers could see the benefits and were soon on board with what was being done.
“Farmers are very tenacious people and when you get something threatening their animals and their businesses, like any business, you will work as hard as you can to minimise that threat.”
In another similarity with M.bovis, there was peer pressure among farmers whose cattle had TB, and those whose stock did not, he said
But Dalziell said the nature of the disease within a high-risk area meant that if a herd was not infected one year, it was likely to be infected the next.
“Everyone sort of knew who had it, and farmers were really open about it.
“Farming communities are really tight, I think most would feel a responsibility to tell their neighbours.”
While TB had not been fully eradicated yet, to have the region considered a low-risk was “fantastic”, he said.
The TB Free eradication programme, which involves testing and pest poisoning, aims to have the all livestock rid of the disease by 2026, and from possums by 2040, and finally for the country to be TB free by 2055.
“There are some comparisons obviously, but both diseases have been pretty demoralising for farmers, and extremely costly but in different ways,” Dalziell said.
Rural Masterton stud breeder, and previous Masterton district councillor David Holmes, said TB eradication was a very “frightening process” for Wairarapa farmers.
“As a stud breeder, every time we came up for our test we were on tenter hooks,” he said.
“You had to go through it to know,” he said.
While Holmes never had any TB-infected cattle, the stress was likely as intense for him as it was for farmers who had infected cattle.
A similar feeling was felt by farmers across the country with M.bovis-infected herds, he said.
TB had been in the country for “donkey’s years”, but the uncertainty surrounding the entry of M.bovis “bewilders” Holmes.
“The reality is we haven’t been told how it got here, perhaps it was bought in illegally, which makes it even worse.”
During the intense TB eradication programme, farmers had the certainty of knowing where it came from and how it was spread as they tackled the disease, he said.
Wairarapa Department of Conservation ranger Jim Flack said the past 25 years of intensive possum control had been “fantastic” for Wairarapa’s bush and birds.
“Possums had been munching their way through Wairarapa’s bush and birds unchecked for decades,” he said.
Now, there is a “network of healthy native bush” for native birds to flourish in, Flack said.
M.bovis disease impact
After an Otago farm was first declared to have Mycoplasma bovis one year ago, 53 properties across the country have tested positive to the disease.
Forty-one of those farms are still waiting for stock to be culled while more than 24,000 cows across the country have already been destroyed.
Six North Island farms in Pahiatua, Masterton, Waikato and Hastings are infected, including one sheep and beef farm in Bideford, near Masterton.
On May 28, the Government made the decision to attempt to eradicate the disease.
It is expected more than 150,000 cattle would be culled.
An estimated $886 million will be spent, under the $1.3 billion estimated cost over 10 years of not acting.
The Government will meet 68 per cent of the cost, with Dairy NZ, and Beef and Lamb NZ meeting the remainder.
The Ministry of Primary Industries is investigating seven possible means of the diseases’ entry into the country – imported live cattle, imported frozen semen, imported embryos, imported veterinary medicines and biological products, imported feed, imported used farm equipment, and other imported live animals.