ANDREW BAKER

Q The problem with Sammy the cockapoo, aged six, is that he is perfectly respectful of other fully grown dogs, regardless of size, but he seems to go out of his way to frighten, bark at and otherwise upset puppies and younger dogs whenever we encounter th

CAROLINE CLARK If Sammy wasn’t exposed to little dogs or puppies during the important socialisation period (three to 12 weeks) then he won’t have learnt how to interact with them. They may even appear alien to him. This can cause a level of anxiety and fear, which often manifests as aggression.

Or, perhaps during his socialisation period, he had an aversive encounter with a small dog and has learned to be fearful of them. As dogs get older and more confident they begin to use more proactive behaviours to try to repel what they think is a threat.

Treatment primarily involves desensitisation and counter-conditioning. You could get someone with a small dog or puppy to meet you in a very quiet location. Make sure that they are far enough away from each other so that Sammy is unreactive. Begin by engaging him in something he enjoys doing and, over time, you should be able to increase their proximity to one another. It’s important not to rush things and do ensure that both dogs remain safely under control.

At the same time, build more positive associations by doing something that Sammy finds emotionally pleasing. This might include play, reward-based training or just being relaxed. This is called counter-conditioning. Very gradually, the intensity of the stimulus is increased as he becomes comfortable and unreactive at each stage of the training.