Dairy Australia is reminding farmers to remain vigilant and on the lookout for mycoplasma in their cows and calves.
An emerging cause of disease in cows and calves in Australian dairy herds for more than a decade, Dairy Australia said mycoplasma had recently occurred in New Zealand.
While only a relatively small number of Australian farms have been affected, disease caused by Mycoplasma bovis can result in lost production, culling and the death of cows and calves.
The infection can be difficult to detect as heifers and cows may carry mycoplasma without showing any signs of infection.
Mycoplasma infections also appear with a range of different symptoms on different farms, including calf pneumonia, head tilt, conjunctivitis, ill thrift, joint swellings, mastitis and even sudden deaths.
Once the infection is established in a herd it is difficult eradicate, as there is no effective vaccination or treatment.
Mycoplasma species can readily spread during milking from one quarter to another in the same cow or other cows via milkers’ hands or liners.
Cows can also become infected via contact with contaminated nasal secretions or uterine fluid.
Semen, embryos and contaminated equipment are also potential sources for transmission.
Calves can become infected by consuming milk from infected cows, contact with contaminated surfaces or contact with other infected calves (including via aerosol).
Dairy Australia said farmers concerned about mycoplasma in their herd should contact their local veterinarian for advice.