Horn Flies1 and Stable Flies:1 Feeding Activity3

An electronic bitometer was used to study the feeding activity of horn flies, Haematobia irritans (L.), feeding on a cow. Females averaged 38.4 feedings/day and spent an average 163 min/day in feeding; males averaged 24 feedings/day and spent an average 96 min/day in feeding. In contrast, female horn flies offered blood in the laboratory averaged 10 feedings/day and spent an average 15.3 min/day in feeding. Gut contents of female horn flies also indicated they fed more than 24 times/day. Female stable flies, Stomoxys calcitrans (L.), averaged 1.8 feedings/day, and males averaged 2.8 feedings/day.