By Cara Sheridan, veterinary advisor with MSD Animal Health

Leptospirosis is one of the most common causes of abortion in cattle in Ireland. It is an endemic disease, meaning that the majority of herds test positive for it.

Leptospirosis is also a zoonosis – it can cause disease in humans. All those working with stock are potentially at risk. Clinical signs of the disease in humans are flu-like symptoms, with headaches and fever. This can occasionally progress to meningitis.

There are two serovars of leptospirosis commonly found in cattle in Ireland – Leptospira interrogans hardjo and Leptospira borgpetersenii hardjo.

Leptospirosis circulates in a herd by direct transmission from infected animals (new infections or carrier animals) or by indirect transmission through urine, birth fluids, milk, contaminated water, or other species – for example, sheep.

It’s very difficult to eradicate as some cows can become carriers. Leptospires can also survive for up to six weeks in wet soil and stagnant water or slow-moving streams.

Clinical signs of Leptospirosis

Early signs are usually mild and transient and therefore may go unnoticed.

Diagnosis of Leptospirosis

Diagnosis of the disease is based on blood sampling and looking for high antibody levels in affected animals.

However, this can prove difficult. Often, the infection is present six-to-12 weeks before clinical signs become apparent (e.g. low pregnancy rates picked up at scanning).

It can also be based on the culturing of urine samples. In addition, leptospiral abortion diagnosis is best based on the identification of bacteria in the foetus. Farmers are encouraged to speak to their vets about investigating leptospirosis in their herds.

Timing of Vaccination

It is essential to vaccinate heifers before their first pregnancy. The primary vaccination course consists of two injections four-to-six weeks apart.

An annual booster before turnout and at least two weeks before breeding is required. It is a 2ml dose, given under the skin to all cattle greater than one month of age. The correct use and timing of the vaccinations are vital to their success. The manufacturer’s recommendations should always be read.

More information

For more information on leptospirosis and how you can keep your herd disease free, just [button link="http://www.bovilis.ie/leptospirosis/"]Click here[/button]