When the flies get bad we run the calves through the shute and spray them with a permecthrin II dilution. I also spray their sleeping areas. Seems to keep the flies away for about 2 1/2 weeks. It can be reapplied every 3 weeks. I only have a few calves so it's not bad to spray them as they are lined up in the alley before the shute. :lol: :lol:
Gnats are reduced a little, but still hang around.