A small possum dug into our coop at 3 am this morning. It killed one of my 12 week old pullets and maimed another. She has several deep bites on her tail. Of course it's Sunday and the vets are all closed, but is there an injectable antibiotic that I could get at Tractor Supply, like Durvet? I've been irrigating the wounds with saline and iodine but she's going to need something intravenous. TIA!