On the face of it, with modern farming methods and the widespread use of insect repellents on cattle, the prospects for the tick wouldn’t appear promising. However, as a vet in practice, I am becoming more aware of the threat to animal health from these parasites all the time.

The most common livestock tick in Ireland is called Ixodes ricinus. The disease associated with this tick which we are all most familiar with is Babesiosis, or redwater. Redwater causes severe anaemia and is often fatal.

However, with relatively new and more accurate tests now available, we are identifying other tick-borne diseases, such as Q Fever and Tickborne Fever.

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The tick has a three-year life cycle, comprising of four stages – egg, larva, nymph and adult. At each stage of this life cycle, the tick needs to bite an animal and have a blood meal before developing on to the next stage. This blood meal takes between three and nine days, depending on the stage, so the vast majority of a tick’s life is spent in the environment.

The environment most suitable for ticks would always be considered as densely vegetated or rough pasture. A lot of modern farms would have well-managed and closely grazed swards. However, due to disease being passed through generations of ticks and the ticks themselves using sheep, wild animals and birds as hosts, infection can persist for years in an area.

Q Fever is caused by a bacteria, Coxiella burnetii, and is a zoonosis, which means that farm staff can suffer symptoms due to contact with infected cattle. These symptoms range from mild flu-like signs to serious chronic ailments. Infected cows can shed bacteria at calving and in their milk. In cattle, Q Fever is usually subclinical, but can cause reduced appetite and late abortion. There have been reports of reduced herd fertility and subclinical mastitis leading to high SCC.

Tickborne Fever is usually seen in late spring or early summer and clinical signs include sudden high temperatures, reduced appetite and milk yield, respiratory distress with coughing, and a general malaise which can make animals more susceptible to secondary infections. In my experience, these animals are poorly responsive to treatment, but symptoms regress over the course of about a week and treatment is usually just supportive.

From a human health point of view, knowing your herd status for these diseases is prudent. Your vet can advise you on the necessary diagnostic tests.

Kieran O’Mahony works at Glen Veterinary Clinic, Blind St, Tipperary, part of XLVets., a group of practices working to achieve a better future for agriculture and veterinary in Ireland. Visit www.xlvet.ie.