In addition to arthropods, there are several species of naturally occurring entomopathogenic fungi that are associated with flies.
These micro-organisms can be found in both intensive and extensive farming systems, and unlike many of the arthropods, grow best in moist area.
Some species have a broad spectrum of activity (e.g. Beauveria bassiana which can infect many insect species). Other species of fungi are more selective (e.g. Metarhizium anisopliae and Paecilomyces fumosoroseus, which are more effective against the face fly and the horn fly).
In addition, some strains of fungi are more active than others.
Most species are only active against adult flies. However, some species also have limited activity against larvae.
Some of the most studied fungi for fly control in livestock systems are Bavaria bassiana and Entomophthora muscae.
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