I don't know wether this belongs in training, genetics or behaviour. I was triggered by the question about Pit Bulls today. Are aggressive dogs born or made? There are certainly lots of very small dogs that strain at the lead, snarl and snap. Their owners often seem almost proud of their 'spirit'. But I look at them (the dog) and think, you are agressive and if you were a larger dog you would be seriously bad news. Even a small dog could inflict considerable damage to a young child and scar them forever. My husband has a scar on his thigh where he was attacked when he was a young child.
I think that a tendency to bite first and ask questions later can certainly be bred for and inherited. However any dog can also be trained (or learn....same thing) that is is advantageous to behave in that way, and I would expect that most dog bites ultimately come down to that. A proportion of those will be provoked by human behaviour (e.g. parents letting the kid crawl all over the dog until one day....).
I think that aggressive dogs are more made than born, even in those breeds that have a bad reputation which sort of goes with the saying "there's not a bad dog, only a bad owner". Aggressive small dogs are a case in point - I've come across many owners of small dogs who think that they're dog doesn't need training because they are small and can be picked up. The only problems I've had with other dogs on walks are from small dogs, off lead with no recall, charging for my dog barking and growling
I can't remember who on the forum said this before now - maybe there is a tendency to "celebrate" the characteristics of the breed, so encourage those traits. Like we encourage retrieving in Labradors, I wonder if people who own pit bulls encourage guarding and aggressive behaviour. Same with terriers etc. I have to say, I meet a great many unpleasant small dogs - but I do wonder if they have a hard time with other much bigger dogs when they are younger and so learn to defend themselves in a snappy, unpleasant way. Charlie avoids Westies like the plague, he has had so many bad encounters with them...
I have always said that too often, owners encourage their dogs to behave like the stereotype , which I abhor . I also believe that aggression can be caused by poor breeding ethics , for example someone who lives near to me was, until very recently, using one of her Labrador dogs as a stud dog, despite the dog being of extremely dubious nature . I don't think that dogs should be categorised as breeds which are " nasty " , far better to categorise owners as being inept in their lack of early socialisation skills, lack of general training etc . So, yes to both , they can be born with certain tendencies if one or the other parent is not of a good nature, but more often it is down to poor ownership skills .
I think made. Interestingly tho in the last two weeks, I've met two labs, showing their teeth, aggressively barking and lunging for Bella on lead, scary
A dog trainer told me some years ago that dogs don't know whether they are big or small. I believe it's owners not so much the breed which now has lots of breeds branded as dangerous which they may not be in the hands of a responsible owner. Any dog is capable of aggression even Labradors and it's dangerous to people around you to think your dog could never be aggressive or have the potential to hurt anyone. No dog can or should be 100% trusted.
When I was a child, there was a couple who lived by us with two Westies. both were very snappy. They told me it was because their jaws weren't properly developed due to being overbred and so they were in constant pain. That is particularly sad. It is far too common to see small dogs getting away with murder just because they are small, and I sometimes wonder if the ones that are snappy are just fed up with being manhandled all the time!