Summer fly burden causes significant welfare harm to horses through irritation, skin lesions and disease transmission, with integrated fly management reducing suffering across the grazing season.
Summer fly welfare in horses is a pervasive, underappreciated welfare problem. Horses under severe fly pressure spend significant energy in fly-avoidance behaviour - foot stamping, skin twitching, head shaking and clustering in tight groups. This chronic irritation reduces feeding time, resting quality and overall wellbeing. For horses with sweet itch, the welfare impact is even more severe. Integrated fly management combines physical barriers, environmental management and selective insecticide use to reduce fly burden without creating resistance or unnecessary chemical exposure. The welfare benefit of good summer fly management is measurable - horses with effective protection show calmer behaviour, maintain better body condition and have fewer fly-related skin and eye problems.