It is for use as an aid in preventing disease caused by Clostridium chauvoei (Blackleg), septicum (Malignant edema), novyi (Black disease), sordellii, perfringens Types C & D (Enterotoxemia), and Haemophilus somnus. You can get it any any cattle supply store
The last time I wormed mine I used the ivermectin pour on for cattle. You should be sure to get the right dose on them or I think they may become ill??? I've heard of ppl putting it on dogs and they get sick if to much is applied but idk if it holds true for deer. Pretty sure I got a good dose on mine last time they were in the chute and they are ok.