One of my friends sister just lost her jack russell from a rattlesnake bite! Said they were working on the new land they bought and it had an old barn on it. The dog kept barking non stop in the barn...they never went to check on it (which I always check when the dogs are barking nonstop, there is normally a reason for it..and everytime I check, they have something!)...anyway, they heard the dog yelp and it ran to them...they seen the two puncture holes on his head (above his eyes)....went in the barn and killed a rattlesnake that was over 5ft long!! The vet said that there was nothing he could do (??) and the poor dog died a few days later....they said he knew and got up from his bed and went outside (at current home with a fenced yard) and went to the fartherest corner of the backyard and that is where he died....