Flies are notorious for causing problems to cattle both by their nuisance factor and by transmitting diseases between animals.
In the UK there are at least 20 species of fly which feed on cattle. Different species of flies feed on different secretions or tissues. Some pierce the skin and feed on blood; while others feed on sweat, skin secretions, saliva, or tears (some flies also feed on urine or faeces).
There are two ways in which flies cause harm to cattle:
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