What type of fly control feed or tubs do you recommend? I had a trailer built that uses half plastic barrel feeders and a metal framework to fasten on 4 cow life rubs on. Thinking about using feed similar to the Wind & Rain with fly control med in it (if it don’t bankrupt me). I tried a tub of it ($180) and it just lasted a few days on 50 head of cows & calves. I’m in southern Illinois.