Efficacy of using parasitic wasps to control stable flies in Kansas feedlots

Release of parasitic wasps has resulted in stable fly reductions averaging 28, 42 and 38% for 1991, 1992, and 1993, respectively, with considerable variation from feedlot to feedlot. Costs for parasites plus sampling averaged $.23, $.32 and $.26 per animal during 1991, 1992, and 1993, respectively. Because stable flies are estimated to cause losses of $5.00 to $30.00 per animal, these costs are very reasonable.