Mice affected hay – What's the risk?

Given the high levels of mice activity NSW has dealt with over the past few months,  producers should be mindful that stored hay or the hay you are buying in, particularly relevant for producers here in the South East, could have some level of contamination from mice.

It is important producers consider their options before using or purchasing potentially contaminated hay, as it can carry risks, such as:

• livestock avoiding hay due to smell
• leptospirosis in cattle
• botulism in livestock.

Leptospirosis, commonly known as ‘Lepto’, is a disease transmitted through mice urine via direct contact or contamination of water and food sources. Strains of the disease can cause abortions and reproductive losses in cattle but not normally in sheep.

Cattle can be vaccinated against Lepto, by giving two injections four to six weeks apart. There is no vaccine available for sheep, but Lepto is not thought to cause clinical disease in sheep.

Botulism is a disease seen in animals that eat dead decaying carcasses, including mice carcasses, or contaminated food sources. Symptoms include paralysis and sudden death, with very few animals recovering.

There is a vaccine available for both cattle and sheep, which requires two injections with a four to six-week interval between them.

If you are planning on feeding contaminated hay, completing vaccination before feeding starts is key.

For more information, contact your district vet.