I had to check some wheat yesterday, and as usual our Lab Noxx accompanied me as he does every day. We have had a lot of rain recently and the woods and thickets have been flooded and has pushed all sorts of animals to the edges. Also yesterday it was sunny and somewhat warm. Noxx has been trained for retrieving and also as a shed horn dog. As we got close to the edge of the field I cast him to make a downwind pass by a Cane thicket to scent for horns and he ran head on into a Cottonmouth snake that was sunning. He got bit on his front Paw and I heard him yelp and when I turned he came running to me and had immediately started limping. I thought he may have got a sticker and couldn't find anything and kind of put it off as not a big deal. He loaded in the truck fairly routinely and I never thought anything else about it until we got to the next farm (45 minutes) and when I opened his kennel, to my horror his front paw and leg was swelled to three times the normal size, and he was having a hard time breathing(seemed rapid and labored). I immediately ran him to his vet and they started him on an IV with meds and painkillers. He is staying at the vets as they have a person watching him all night. He made it through the night and when I got there today he had lost skin on his paw and part of his pad and it had started moving up his leg and still had a lot of swelling. He will continue to stay until we get an all clear. I think he will be fine but will make me be way more aware of where I send him as I feel horrible as I put him in that situation. I couldn't imagine having to tell my girls who are 4 and 7 something had happened to him. Please be vigilant.