It can also manifest as ear infections or pneumonia occurring in young calves.

Cause

The disease is caused by the bacteria mycoplasma bovis and usually occurs after the introduction of an infected animal into a herd. It can be a devastating disease that can occur all of a sudden and spread quickly throughout the herd and is frequently associated with an underlying suppression of the immune system.

Symptoms

Symptoms can include secretions from nose and eyes along with drooping ears, all signs of pneumonia. They can also develop ear infections. If not treated quickly swelling happens in the legs leading to lameness. Weanlings are more likely to suffer from respiratory problems while milking cows will be prone to mastitis. All age groups will be prone to joint ill (arthritis) type problems. Clinically, not only are joints hot, swollen and painful, but tendons above and below may also be affected. The lameness caused by mycoplasma is exceptionally painful.

Treatment

Treatment of mycoplasma infections is not always rewarding. Antibiotic treatment of mycoplasma mastitis is usually hopeless. Affected cows need to be segregated from non-infected cows. They usually go back in milk, so much so they need to be dried off and culled.

In the case of mycoplasma pneumonia, treatment courses of up to 10 days are required routinely. This bacteria has a unique structure, which requires specific antibiotics.

Milk testing may be required to diagnose the disease. Other forms of diagnosis include testing fluid from a swollen joint and blood testing. It is recommended that your vet takes these samples within the first two to three days of the clinical disease.

Prevention and control

While there are some reports of effective use of specially manufactured autogenous vaccines in young calves in other countries, these products are not available in Ireland. As no direct vaccine exists for mycoplasma bovis, protecting against respiratory viral and bacterial diseases and other management factors that predispose to respiratory diseases are essential to curb losses.

Because environmental contamination with Mycoplasma has been reported, cleaning of the environment, particularly watering equipment, after removing groups of affected cattle is recommended.

Preventive use of antibiotics in cohort animals, where a diagnosis has been confirmed, has also proved to be useful in restricting losses. This would obviously mean waiting until first clinical cases arise rather than the approach of treating with long-acting antibiotic on arrival at the feedlot.