December 30, 2021

Don’t relent on fly and tick control late in the grazing season

By Mike Catangui, Ph. D

The face fly (Musca autumnalis) [Fig. 1] is a known vector of the bacterium that causes pinkeye disease in cattle. Pinkeye disease, if not immediately treated, can result in cattle blindness.

Fig. 1. Face flies feeding on the secretions of the eyes and nose of a cow.

Fall fly and tick control

Research conducted by MWI Animal Health Technical Services in central Nebraska indicated that face fly, horn fly (Haematobia irritans) [Fig. 2] and stable fly (Stomoxys calcitrans) [Fig. 3] populations peak in late summer through early fall.

In the southern United States, ticks can also become numerous at this time of year [Fig. 4]. Ticks are persistent blood feeders and vectors of several disease-causing microorganisms. Visible injuries (e.g., gotched or drooping ears) [Fig. 4] caused by ticks can lower the market value of cattle.

It is imperative for ranchers to not relent on their fly and tick control programs late in the season to ensure optimum cattle health and production.

For immediate reduction in fly and tick numbers, the herd can be sprayed with an insecticide using a mist sprayer [Fig. 5]. Water-based [Table 1] and oil-based [Table 2] insecticides can be used as on-animal sprays to control flies and ticks on pastured beef cattle.