Vets plan to hoof dairy cows' health problems
A two-year pilot study into a hoof infection in dairy herds will get under way in Taranaki next month.
Inglewood vet Neil Chesterton, an international authority on lameness in pasture-fed cattle, detected bovine digital dermatitis (BDD) in a Taranaki herd in 2012.
BDD is a bacterial infection that features a strawberry lesion on the skin on the back of the hoof. "It doesn't cause much lameness, but it makes the foot uncomfortable," Chesterton said. "A cow with it favours the foot when standing for milking."
Since its discovery two years ago, at least 12 cases of BDD have been confirmed in Taranaki and the infection, which lowers production and fertility, has also been found in more than 50 herds around the country. Vets are now looking for BDD in herds throughout New Zealand.
In an effort to understand the disease and combat its spread, Chesterton has designed a two- year pilot study of about 70,000 cows on 300 farms within Inglewood Veterinary Services' practice. He will be assisted by colleague Peter Benn.
The two vets hope to find out how the infection spreads so measures can be put in place to prevent its establishment in dairy herds.
The study will begin next month on early calving farms and will continue until May.
In the first year a baseline of the incidence of BDD will be established and the study will be repeated next year. The findings will establish guidelines for a nationwide study.
It's a world first because no other country has investigated the disease in its early stages of colonisation.
"New Zealand is the only country in the world where the disease is not endemic on dairy farms," Chesterton said.
"It's widespread in Europe, the UK, North and South America and it looks as though it's taken hold in Australia.
"Other countries have waited until it's a serious problem before they investigate it. Peter and I want to look at it early to prevent it becoming a huge problem."
Funding has been received from Massey University, the Ministry for Primary Industries and Waikato-based Shoof International, which develops, manufactures and exports agricultural and veterinary equipment.
"It won't cost the farmers anything to have their herds screened," he said.
The funding covers the cost of screening and advice to farmers on preventing the infection if it's not in their herd or controlling it if it is present.
Benn will visit farms where an infection is suspected and take a sample for laboratory analysis and confirmation.
Testing of samples will be at a reduced rate at Gribbles Veterinary Laboratory in Palmerston North.
Every cow in every herd whose owners are willing to take part in the study will be screened during milking.
"The screening is quick and won't hold up milking," Chesterton said.
Each farm will be allocated a number to ensure anonymity. Farmers will be contacted about their milking times and two farms will be visited daily, five days a week, over eight months.
Each animal's back feet will be cleaned with a hose and checked with a torch by veterinary technician Amy Carroll.
"Amy will inspect every cow and will let the farmer know whether or not she suspects the infection is present."
Chesterton is hoping only a few herds will be found with the infection.
"But we don't know - and we want to know the truth.
"The study will give us a picture of what the disease is doing in one area of New Zealand.
"We will know within a month of the start how prevalent it is."
A Massey University masters student will manage the data gathered during the study.
He said many farmers were unaware of the infection because it did not cause severe lameness. "We want to make them more aware of it so they start looking for it."
He's appealing to any farmers who think it's present in their herds to contact him as soon as possible rather than wait for the project to begin.
Taranaki Daily News