Castration and Behaviour
21st Jun, 2017
In the UK we castrate male dogs for many reasons, primarily to avoid unwanted pregnancies but we also neuter to prevent roaming, to control unwanted sexual behaviours, in the hope of calming a dog down, in order to prevent aggression problems developing or to solve an existing aggression problem. There is mixed evidence as the efficacy of castration for all of these reasons, the only sure fire thing that castration will solve is unwanted pregnancies!
However, if not already developed castration can be effective in preventing:
• Inter-male aggression;
• unwanted sexual behaviours;
• and to prevent roaming.
But once a dog is already acting out these behaviours they become learned and castration is unlikely to be effective on its own. Even when castration is relevant, there is only a percentage chance that it will work. This varies from 90% for some problems, such as roaming to find potential mates, down to 50% for others such as inappropriate scent marking. This is because the male brain is programmed to display male behaviour by testosterone even before birth.
The statistics show that entire male dogs are more likely to show aggression than female dogs or neutered males. Entire male dogs are more likely to be aggressive because they are more competitive over things they value than are either females or neutered males. They may be more confident in their ability to control things they think are important and as a result more likely to use aggression when confronted. Castrating dogs before they start to show aggression may well reduce the future likelihood of some individuals becoming aggressive, but again, once they have learned that aggression is a successful response, the learnt behaviour does not go away.
In cases where aggression is motivated by fear, which is not a testosterone related problem castration is not likely to be effective. Indeed, there is strong anecdotal evidence that castrating a dog can actually aggravate defensive aggression. The thinking here is simply that testosterone confers confidence and that the massive drop in testosterone following castration can lead to a corresponding fall in confidence thereby exacerbating defensive aggression and other fear-related problems. Accurate diagnosis is therefore essential to determine whether castration is appropriate.
It is generally accepted in the behavioural profession to advise against castrating a dog displaying fear related aggression or other fear related behaviour problems for this reason. It is wise to allow a dog to mature and for his confidence to develop before considering castration. Potential guide dogs in the UK have their confidence levels monitored and castration is timed to suit each individual. This may mean leaving the less confident dogs until almost a year old while others are done at 8 months.
If a dog is already showing aggression it is advisable to seek a professional behavioural opinion as to exactly what the cause is before considering neutering as an option. If the accurate diagnosis of a problem shows that castration is likely to help, the chances of success are greatly improved if the operation is done in conjunction with behaviour modification therapy (Claire Kirby BSc AS/Dip (CABC).