Horn flies are one of the major pests of cattle and is found in most cattle producing areas of the world. (Hendrix, 2013) Adult Horn flies spend their entire life on the host, they only leave to oviposit eggs on the manure of the cattle (Hendrix, 2013) Horn flies have the appearance of the common house , slightly smaller in size. (Tomberlin, 2004)The full cycle of horn flies from egg to adult stage ranges from 20-30 days, adult flies live for approximately 3 weeks and feed on the host 20 to 30 times a day (Tomberlin, 2004). Horn flies have higher populations in the spring and fall then in the high heat of summer AgriLife, n.d ). When temperatures are less than 21°C the horn flies will gather around the horns of cattle, warmer climates will bring flies to collect on the shoulders, back and sides. High temperatures with strong sun rays cause the horn flies to gather on the ventral abdomen. (Hendrix, 2013). Cattle infected by horn flies show signs of irritation by kicking at their stomachs, flicking their tails and twitching their flanks(AgriLife, n.d ).
Face flies look similar to the common house fly (Hendrix, 2013). These flies are nonbiting, but they feed on the excretions from animal’s mucus membranes, and the liquid deposits found in manure. (Hendrix, 2013). Face flies are strong flyers and travel from host to host, this gives them an opportunity to transmit diseases throughout the livestock herd (Hendrix, 2013). A common infections caused by the face fly are ketatoconjunctivitis which is more commonly known as pink eye, and the transfer of Thelazia spp more commonly known as eye worms (Hendrix, 2013) In order to limit the face fly and be rid of the horn fly a method of control needs to be used.