Rosemarie Tang continues her discussion of the causes of aggressive behaviour in dogs. The certified animal trainer and behaviour counsellor also outlines what to do when a dog first shows aggressive behaviour before the cause is identified, what to do about an aggressive puppy and what to do if you encounter a strange aggressive dog when out.

Tang says there are three more forms of aggressive behaviour. "One of these is predatory aggression. The behaviour is motivated by the need to obtain food and the best way to avoid a dog developing predatory behaviour towards other family pets is to socialise them when they are young."

Another is redirected aggression, which can occur due to over-arousal/excitement, with the aggression directed at the closest target. "Avoid putting a dog in situations where redirected aggression might occur and if you see a situation building, interfere before it escalates."

Finally, there is idiopathic aggression, which is an unprovoked and unpredictable form of aggression, with dogs suffering from it sometimes being described as having a crazed look in the eyes just before they become violent. The cause is not known and it can be confused with other forms of aggression and needs to be diagnosed by a professional.

"If a dog is suddenly threatening or being aggressive to the owner or [other people] it lives with, the first and most important thing to do is to take steps to protect everyone. Aggressive behaviour, if left untreated, can get worse over time and, eventually, may be the cause of harm to members of the household or other animals," Tang says.

She says the owner must manage the environment to minimise opportunities to show aggressive behaviour and avoid situations that may trigger threats or an attack. "Contact the dog's veterinarian immediately to have the dog evaluated for medical conditions that could be influencing its aggression. It is very important that children, older adults and those with disabilities be kept safe from an aggressive dog."

After medical causes have been ruled out, seek help from a veterinary behaviourist to establish the exact cause of aggression and develop a behaviour modification programme.

"In treating aggressive behaviour cases, my role is a rehabilitation trainer working closely with the veterinary behaviourist to demonstrate and implement the practical aspects of the treatment plan carefully in order to avoid injury, maximise the chances of success and not make the problem worse."

When it comes to aggressive puppies there are two main causes: resource guarding and fear. Tang says that resource guarding often develops in large litters where there is a lot of squabbling over food or other resources. Preventative desensitisation exercises are very useful in these instances. Fear-based aggression is often shown by nervous and shy puppies, which need lots of positive socialisation experiences to help them feel safe and build confidence.

Tang says: "Early socialisation may reduce aggression. It's critically important that a puppy thoroughly enjoys the company and actions of people, and gets lots of positive exposure to the rest of the world before the critical socialisation period ends at 12 to 16 weeks. Temperament problems must be prevented during early puppyhood because rehabilitating adult dogs is more complicated and time-consuming."

Her main tips for puppies are:

  • Socialise the puppy early, often and throughout its lifetime.
  • Actively teach the puppy to be confident and friendly.
  • Always use only positive, reward-based puppy training techniques.
  • Make training sessions fun for the puppy and always end on a positive note.
  • Never punish the puppy by shouting, smacking or scaring it.

"I believe relatively few dogs are beyond help. If an owner is committed and gets the right professional help, there's a good chance that the behaviour will improve."

Her advice for those that may encounter an aggressive dog in public (and the owner is not in control) is to take steps to reduce the risk of being attacked. This includes: don't panic, make yourself as neutral as possible, stand sideways (not facing the dog), no sudden movements, don't extend hands or arms (keep them by your side), avoid eye contact and back away, but do not run away.

"There are no guarantees that this will save you from being bitten but it will reduce the risk," Tang says.

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