Before and after neutering your cat

¿Should I neuter my cat or not? There comes a time when cat owners must face this dilemma. This is a decision that must be taken together with professional veterinarians that will probably result in behavioural changes.

Neutering is a type of surgery that consists of removing the testicles of the male, where most of the testosterone that is present in their bodies is produced. This hormone controls their sexual behaviour and related actions, such as scent-marking, aggressiveness towards other males and roaming in search of females in oestrus.

By neutering them, male cats normally lose their sexual behaviour. However, some males may keep their mating instinct or interest for females for months, or even for life.

Neutering also eliminates or minimises the frequency of breeding-related behaviours in 80–90% of cases. The reduction of this type of behaviour has many positive consequences for both cats and their owners. For cats with access to the outside, the lack of excessive roaming reduces the risk of accidents. The inhibition of their tendency to fight against other males reduces the risk of suffering bites and scratches, which sometimes transfer very serious illnesses, such as the feline immunodeficiency virus or feline leukaemia. The reduction of scent-marking brings plenty of advantages, especially for those cat owners who don't have outdoor access. However, neutering does not eliminate scent-marking completely, since this is a behaviour controlled not only by sexual hormones but by the level of stress of the animal. With regard to scent-making, the difference between un-neutered cats and neutered cats is the smell of their urine, which is less intense in neutered cats due to the low levels of felinine – a substance that provides a strong scent to urine and which is abundant in un-neutered cats.

All these behavioural changes take place immediately after neutering or, in some cases, after several weeks. Neither their environment nor previous experience seem to have a deep effect on these changes, and neither does their age, since neutering pre-pubertal cats (when they are 6–7 months old) produces the same effects as in adult cats.

However, we cannot expect neutering to solve all the behavioural issues of our cats. Although neutering produces some changes in the behavioural aspects of cats, it does not change their personality. If you are planning to neuter your cat to prevent or solve behavioural problems, it is important that you first get to know the side effects of neutering and establish realistic expectations on the improvements you may obtain.