Male dogs are more frequently neutered than females to influence their behaviour. However, some dogs exhibit undesired behaviour such as aggression, as a result of neutering. Surprisingly, dog trainers and behavioural therapists recommend neutering far less frequently than veterinarians, while they are schooled in the field of canine behaviour. This is the conclusion of a study conducted by Wageningen University & Research.
Little is known about the reasons that drive dog owners to have their dog neutered. This study focusses on male dogs since over half of the male dogs are neutered for reasons of behaviour, such as aggression. This applies to only 11 per cent of the female dogs.
Effect not always positive
Remarkably, neutering does not always result in improved behaviour. Occasionally, aggression is increased. 'For example, aggression can increase if a male dog is already insecure, and grows even more so as a result of the castration,' says researcher Pascalle Roulaux. She leans on personal experience; her neutered Labrador has this issue.
Aggression increased in eighteen per cent of the neutered dogs. It is therefore important for a sound decision to weigh the pro's and con's before castrating a male dog, thus safeguarding the relationship between the dog and its owner. Fellow researcher Ineke van Herwijnen observed an increase in aggression and disobedience in dogs with dissatisfied owners. Less satisfied owners are more likely to rehome their dog, making the canine-human relationship of key importance to the dog's wellbeing.
Balance between medical and behavioural advice
In total, some 500 owners of neutered and intact dogs provided information through an online survey. Three quarters had been advised by a vet, half by a dog trainer, and only 38 per cent by a behavioural therapist. Veterinarians are more likely to recommend castrating a dog than trainers or therapists.
It would seem that dog owners are mainly influenced by vets in choosing castration. This is relevant since vets are more likely to give advice from a medical point of view than from a behavioural perspective.
'For a sound decision on the issue of neutering, it is important to find a balance between medical and behavioural advice', Roulaux stresses. For a correct balance, more research on the behavioural effects of neutering is needed. Precisely because so little is known, there is a risk that behaviour is not sufficiently considered in the choice to neuter.