Since you said you have no way of getting your hands on him I assume you don't have the ability to tranq him, and if that is true, I would encourage you to get a dart gun so you will have it for the future. If you are raising deer, there will be a day you will need it - no doubt! I personally have had bucks break their antlers from time to time, a small part of, and I never did anything and they were fine, but that doesn't mean you won't have trouble. If guys are saying you need to do something right away, then you might want to listen to them, cause they have probably had the problem they are trying to save you from. If you come across the ability to get your hands on him should it be necessary, and some say it is, then I would rub a bug repellent (with deet) around his head, face, and ears inside and out. His ears waving around with repellent on them will help keep flies away. CyLence is a product many recommend, so I would apply that to him. I would also liberally apply an antibiotic cream all over where you cut. And of course give him a shot of your preferred antibiotic. But yes there is an antibiotic you give in water - oxytetracyclene. It is a 5 day treatment that comes in a packet that is good for 120 gallons of water for the theraputic treatment of deer and is sold at Farm&Fleet, and you have to dump out daily what they don't drink and give fresh. I am not recommending this product for your situation and I'm not saying you shouldn't use it, just saying it's available. You can also pick up CyLence there as well. Good luck!