Start your scouting and preparation for tick and fly season now

Tim McDermott DVM, OSU Extension Educator, Franklin County (originally published in Farm and Dairy)

Visit, your guide to ticks, mosquitoes, and other biting pests. Photo: Anna Pasternak, UK entomology graduate student

As I write this article, it is ninety degrees outside in the first week of May! It is time to start thinking about how we can keep our grazing animals safe from the various arthropods that can cause medical problems, production losses, and economic impact. We have always made plans for fly control over the summer, but it is time we consider adding tick control into our prevention and treatment plans as well. I wrote an update on Longhorned ticks and Theileria in the March 7th All About Grazing section, “What to watch for with Longhorned Ticks and Theileria in Ohio in 2024” but here is a quick refresher.

As of the beginning of 2024 we had positively identified ALHT in 11 counties in Ohio including Franklin, Delaware, Ross, Gallia, Vinton, Jackson, Athens, Morgan, Monroe, Belmont, and Guernsey county. We anticipate finding more positive counties in 2024 as this tick likes to feed on many different species of wildlife and therefore can move on wildlife while they are feeding over a 7–10-day period. To learn more about ALHT check out the BITE SITE link below.

Theileria is a protozoal blood parasite that affects cattle. It can cause increased heart rates and respiratory rates, anemia, jaundice, open cows, and increased mortality. There is no approved treatment, except supportive, approved in the US. We have had positive diagnosis through Ohio’s Animal Disease and Diagnostic Laboratory and Virginia’s ViTALs laboratory of Theileria orientalis IKEDA in eight counties including Crawford, Guernsey, Adams, Columbiana, Tuscarawas, Monroe, Belmont, and Harrison counties. The Longhorned tick is the primary vector of Theileria in Ohio. Other routes that we are seeing this disease enter the state are through purchased cattle coming from states that have high rates of Theileria, as once the cows have recovered from disease, they become asymptomatic carriers.

I had discussions with producers last year about when to start scouting for Longhorned ticks and what you use on cattle that protects against them. I think the time to start scouting is now! While Longhorned ticks prefer heat and humidity, and most of our largest outbreaks of ticks in high numbers have occurred in July, we have seen that Longhorned tick can emerge as soon as the weather works for them and in fact, we had our first outbreak in 2023 in April! The other discussions I have had with producers is regarding using fly products and do fly products also give protection against ticks? While some fly protection and prevention products also work to prevent ticks, that is not the case with every product. It is important that you read, understand, and follow the label on all pesticides and that label will provide the necessary guidance on what pest you are allowed treat for. Long story short, it has to be labelled for use on flies and ticks to be effective against flies and ticks. That still gives us several choices. The next answer is what form of product do we use and when do we apply? I have found that those choices have to be individual to the farm and the production operation. You know how you work animals best and each farm is different. Making sure you are picking the correct product and are scouting to find out when the pests are coming are two of the major inputs into determining which product to use, and when to use it.

Want to learn more about how you can keep yourself, your family and your animals tick safe? Check out the OSU BITE SITE @