Mycoplasma – know the signs

As Mycoplasma continues to dominate headlines, N8N asks Anexa FPC veterinarian John Penry how farmers can best manage the risk on their properties.

“The main advice is do not purchase cattle unless you have to, do not commingle cattle from other farms unless you have to. Be mindful in your herd of looking for the signs of the disease.”

As ‘gypsy day’ approaches, he says keeping animals from different herds separate, while advisable, is probably not achievable.

“Stock trucks should be washed between loads, if possible, and farmers should transport only herd groups in the one load and not multiple farms.”

Symptoms to be aware of –

Adult cows:
Mastitis that is often poorly responsive to treatment and in multiple quarters
Diffuse swelling of the joints/legs with associated lameness
Pneumonia

Calves:
Acute and severe pneumonia
Diffuse swelling of the joints/legs with associated lameness
Head tilt caused by an inner ear infection
Conjunctivitis

“Symptoms in either ages of animals can be seen in groups. It is not uncommon to see symptoms in cows (like mastitis as described) in conjunction with affected calves.”

Click here for the Dairy NZ fact sheet on signs of Mycoplasma bovis.

Dr Penry says farmers should work closely with their vet and Ministry of Primary Industries vet staff if they think there may be a problem.

“This has to be assessed and handled on a case-by-case basis.”

He says Anexa has fielded a number of inquiries about the disease, both of a general nature and more specific to individual farms.

“All testing is currently being done through the MPI lab and can only happen as they assess a herd, with a private vet, and decide on the appropriateness of testing.”

All herds in New Zealand have undergone two bulk milk tests. “This is a molecular test which looks for DNA from the bacteria.” He wasn’t able to comment on the cost of the test but says in Australia it typically costs around $60.

Asked about the future prior to the recent government decision to attempt eradication, Dr Penry said other countries where M. bovis was endemic have sporadic cases in affected herds.

“The example from other countries is that the more cattle are traded between farms, or commingled as heifers, the more the disease ends up on multiple farms in a district.”

John Penry is Group Head of Extension and Advisory Services at Anexa FVC.