Disease check: Leptospirosis

Learn how to tackle leptospirosis as part of Farmers Weekly’s disease check series

Symptoms

Leptospirosis is part of the complex that reduces productivity in beef herds, says Robert Anderson, Merlin Vet Group. “Lepto impacts on fertility, influencing high barren rates and abortion, which ultimately effects productivity.”

It also has the added risk of human infection manifesting itself as flu-like symptoms.

Worryingly, results from Intervet/Schering Plough show 68% of dairy farms and 65% of beef farms tested had been exposed to leptospirosis along with 65% of beef farms.

In dairy herds, leptospirosis can cause infertility and abortion alongside sudden milk drop, says Den Leonard, Lambert, Leonard and May. “Milk drop affected animals will typically go from looking ‘milky’ to dry.”

“Work carried out at Liverpool University showed cows positive for leptospirosis had reduced conception rates compared to negative individuals.”

How is it spread?

Leptospirosis is caused by a bacterium that lives in the kidneys of carriers and is spread in the urine.

“When infected urine makes contact with mucosal surfaces, such as the nostrils, a new infection will form.”

Consequently bacteria can be spread through urine, water supplies, close confinement and at pasture.

Sheep also form an added source of infection, increasing the likelihood of infection on mixed farms.

Testing and control

The disease can be tested for using milk and bloods, but it is difficult to categorically say it is the cause of the problem, says Mr Leonard.

“The best cause of action is vaccination. Research has shown vaccinated cows in an endemically infected herd had 19% better pregnancy rates and almost 17% less culling compared to unvaccinated animals.”

It is possible to blanket treat a herd with antibiotics to reduce the problem and then vaccinate, but this is costly, he says. “Commonly, bought in animals can be treated with antibiotics and then vaccinated before being introduced into the herd.”

For more from our disease check series click here.