For a number of years, we have been utilising fly parasites as part of our fly control protocols to build a sustainable reduction in fly population on farm.

Biting and nuisance flies cause all sorts of problems during the summer, especially on dairy farms and more intensive systems. Issues include Summer Mastitis and New Forest Eye, as well as reduced grazing time through increased cow movement and subsequent reduced yield.

The process starts when the female parasites lay their eggs in the pupae of developing nuisance flies. The eggs then hatch and feed on the dead fly larvae before emerging and going on to parasitise many more nuisance fly pupae in the same way. Each female is capable of parasitising up to 350 nuisance fly pupae every day. So, when you take into account that approximately 85% of all the flies on a farm are in developing stages (pupae and maggots), it makes a lot of sense to stop them there at source rather than killing them as adults using insecticides. By the time an adult fly lands on a cow treated with a topical fly product and is killed it may well already have laid hundreds of eggs, perpetuating the fly problem.

But of course, as with any biological control, it takes time for results to show. The life cycle of the fly parasites takes around 18-28 days. Whereas the life cycle of the nuisance flies takes somewhat less time and is completed in two weeks. This is why we recommend thinking about fly control now rather than when flies start to hatch! It becomes harder to stay on top of the population, if you are playing catch – up.

Additionally, for the first few years it is beneficial to use in conjunction with more traditional approaches; as well as focusing on farm cleanliness.

With parasites, the greatest benefits are seen when they are used regularly. This allows a build-up of parasitic flies and suppression of breeding numbers of the nuisance flies. One study conducted in Argentina recorded a 90% reduction in fly population when compared to untreated control farms!

Your vet techs can help roll out fly control, we are always happy to help!

Although you may not believe us, the warm, dry weather will creep up on us quicker than we think so now is your chance to get ahead with fly control! Give us a call for more information.