Farmers urged to consult their vets as Theileria cases rise
The New Zealand Veterinary Association (NZVA) is encouraging farmers to consult their vet about suspected cases of
Theileria on their farms, and how to best manage Theileria, as the latest data from the Ministry of Primary Industries
shows an increase this season in the number of cattle infected with the disease. Naïve cattle that have been moved into
affected areas are particularly at risk.
Theileria, which causes anaemia in cows and is spread by ticks, affects cattle and is not a human or food safety issue.
Signs of Theileria include lethargy, low appetite and reduced milk production.
Dr Jenny Weston, President of the NZVA Society of Dairy Cattle Veterinarians, says that vets play a key role in working
collaboratively with farmers to provide advice, taking both a preventive and proactive approach to minimise the disease.
“This includes knowing the risks for cattle, putting in place measures such as strategic tick control and managing
movement of animals to reduce risk, and having a plan for early identification and management of affected animals.”
“We urge farmers to remain vigilant, and to speak to their local vet if they have any concerns about their cattle,” she
says. “Vets are on high alert and able to help monitor the situation for their farmer clients to identify infection
early and put in place the best management practices currently available.”
She adds that relying solely on tick treatments may not necessarily be effective as a prevention against the disease,
especially for animals that have never been exposed to Theileria before, such as cows moving to a new farm in another
region.
“Sometimes it is not clear whether cattle have immunity to the disease or not and therefore it is recommended to check
their status before moving.”
“It is also important to give some thought regarding movement of pregnant dairy cattle next June. Movement of any naïve
cattle to the endemic areas of the North Island places them at considerable risk of disease and broadly speaking is
inadvisable.”
The new Veterinary Handbook on Theileria, released in July, comprehensively outlines the most effective strategies for
differing farm circumstances. It includes up-to-date advice on: treatments once animals are showing clinical signs,
blood transfusions if appropriate, lowering stress levels by once-a-day milking and keeping cows close to the shed, as
well as good nutrition and husbandry. Methods of clinical diagnosis and herd screening to ensure early detection of
affected animals are also included.
The Veterinary Handbook was developed by the Theileria Working Group and published by MPI and NZVA, and includes
information to assist vets to determine a whole-herd approach when individual animals are suspected or diagnosed.
“Vets are also receiving regular updates from both MPI and NZVA about Theileria so are up with the latest developments
to assist farmers at this challenging time,” says Dr Weston.
ends