(Musca autumnalis)

Location: Pasture

Named for where it congregates, this known vector of cattle eye diseases is commonly found on the faces of cattle, feeding on secretions around the eyes, nose, and mouth and potentially spreading infection-causing bacteria such as bovine pinkeye. The pest develops in fresh, undisturbed manure and can be identified by its house-fly-like size, yellowish-orange striped abdomen on males, and sponging mouthparts.

(Haematobia irritans)

Location: Pasture

Typically clustered on the backs of cattle, the horn fly feeds on the blood of livestock, taking up to 40 blood meals per day and rarely leaving its host except when females lay eggs in fresh manure. The resulting stress from blood loss and energy depletion can lead to reduced weight gain, lower feed efficiency, and decreased milk yield, and the pest can be identified by its smaller size compared to other flies, brownish-gray to black coloring, and piercing, sucking mouthparts.

(Stomoxys calcitrans)

Location: Confined

Stable flies are biting insects that primarily target the legs of livestock, and the female’s painful bites cause stress and discomfort that can reduce weight gain and overall productivity in cattle and other animals. They can be identified by a dull-gray color, a distinct checkerboard pattern on the abdomen, and a size similar to house and face flies.

(Musca domestica)

Location: Confined

The house fly thrives in both suburban settings and farm or ranch environments where it feeds on organic matter such as feedstuffs, animal manure, and garbage. Because it adapts easily and reproduces rapidly, it can quickly become a nuisance and a sanitation concern. It can be identified by four distinct stripes on the thorax, sponging mouthparts, and a pale yellowish abdomen.