Desexing, neutering or surgical sterilisation of pets

Surgical sterilisation is a controversial topic. The questions are
1)Should I sterilise my pet?
2)What is the best age to have the procedure performed?

Let me give you a hint, there is no “one right answer” to either of these questions as it depends on many factors.

Surgical sterilisation of a female dog or cat is called a spey and involves removing the ovaries and usually the uterus. In a male, the procedure is called a castration and it involves removing the testicles. The result is the pet loses the ability to reproduce and no longer produces the sex hormones -oestrogen, progesterone and testosterone.

With any surgical procedure, there are some risks (anaesthetic complication’s, wound breakdowns or infections, bleeding etc.) but these can be minimised with good standards of care by both the veterinary team and the post-operative care given at home.

The main question is why and when do we desex our pet?

Advantages of desexing include:

population control – desexing prevents unwanted litters. It is a hugely rewarding experience going through a pregnancy and birthing with your pet BUT don’t take it lightly. It is very expensive (even if you do sell them all) and time consuming to raise a litter and there is always the problem of unwanted puppies and kittens ending up in shelters and pounds.

behavioural benefits– By removing the sex hormones there is dramatic reduction in the tendency to want to escape and roam and possibly get hurt in the process (e.g. hit by car, wounds going over/ under fences etc.). Desexing greatly reduces intermale aggression (not fear aggression) and hence fighting which can result in serious wounds, painful abscesses and in cats the transmission of feline aids. Other benefits include a reduction in urine marking, mounting and masturbation as well as not having females coming into heat spotting blood through the house or cats calling (they get very affectionate, vocal and sound like they are in agony!)

When is the best time to desex my pet?
Traditionally desexing was performed around the 6 months of age. Early desexing has become more popular as puberty can occur before this (especially cats), many of the shelters or breeders will not rehome a pet until they have been desexed and generally the procedure has a shorter surgery time and healing (but slightly higher risk of anaesthetic in paediatrics).

The medical effects of desexing depend on the sex of the pet, the age desexing is performed as well as the breed.

In male dogs:
Desexing before the age of 6 months can cause a slight increase in the incidence of sugar diabetes, some cancers (e.g. of the bone, bladder, spleen and prostate) and there is a higher rate of orthopaedic disease (hip dysplasia and cranial cruciate ligament injury) in some large breed dogs e.g. German shepherd and Retriever. Whereas desexing male dogs after 1 year of age or not desexing at all increases the risk of hypothyroidism, some cancers (e.g. of testicles and perianal skin), prostate disease (hyperplasia, cysts, infections), and perineal hernias.

In female dogs:
Desexing before their first heat may cause a higher risk of hormone responsive urine incontinence and a slight increase in risk of some tumours (of the bone, bladder and spleen), peri-vulva dermatitis and vaginitis. Desexing after their first season significantly increases the risk of breast cancer (risk increases with each cycle), ovarian problems (cysts, cancer) and uterine infections (pyometra).

Obviously desexing eliminates some diseases (i.e. you can’t get testicular cancer if you don’t have testicles, or a pyometra if you don’t have ovaries and a uterus) but it is important to remember the studies done are not on every breed of dog and an increase / decrease in risk is just that i.e. it does not mean your pet will / will not get the disease.

Currently the consensus is to recommend desexing for most pets due to the benefits on population control and pet behaviour. The jury is still out on the best age to have the procedure performed -it is really something you should discuss with your vet for your individual pet.