The story above rather illustrates how we have come to take the good nature of dogs for granted. The number of times I've heard people say that the dog has never shown any signs of biting before - just after it has bitten a child or chased and attacked livestock. It is a reminder that a dog is a dog and is still servant to the instincts and drives buried deep within it and this is so often overlooked. I'm as big an offender as the next person and have leant heavily on all my dogs good natures.
The working collie from the next door farm to us in Cornwall was a hard working and trustworthy dog. He worked the sheep and cattle on the farm, never strayed and would defend his territory. One day he savaged four of our sheep, three of which died and one had to be put to sleep. Three others lost their lambs. We heard the commotion and got there as the next door neighbour did. The dog went back to working on his own farm and was never a problem again. One of our own Greyhounds, who walked quietly past the chickens every day of her life for two and half years, was left out of sight for a couple of minutes. We ended up with five dead chickens. In both cases it was lack of respect on the part of the humans concerned that caused these incidents. We should of known better than to leave the Greyhound loose on her own and the farmer the same with the collie.
What is viscious and what is a dog acting naturally with no leader in sight?