The border herder who had been raising for three years suddenly bit people, probably because he was afraid or uneasy and attacked people. This may be caused by insufficient socialization, lack of training or abuse.
1. The dog senses danger and wants to protect its owner. It may be that some strangers made the dog feel threatened and therefore launched an attack on the strangers.
2. Dogs are naturally fond of chasing and fighting with dogs. If the dog is too busy chasing and fighting, it is very likely that the dog will accidentally bite the person when playing.
3. The dog is more irritable because of illness. The dog is uncomfortable and has many symptoms. The owner should pay attention to observation.
4. The competition in the living environment of animals is relatively fierce, so animals are very vigilant, and the same is true for dogs. If dogs have also been in such an environment, then their vigilance will be very strong.