Sterilisation is another controversial subject. The two most popular reasons for desexing a dog are: population and behaviour control. For many dogs neutering will be the most significant surgical procedure they experience. All surgery incurs some risk of complications, including adverse reactions to anaesthesia, haemorrhage, inflammation, infection, etc. Even with specialised facilities it is often difficult to manage both male and female dogs that have not been sterilised.

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So, exactly what is desexing of a dog? It is the removal of the gonads (body parts responsible for allowing the production of sperm and eggs to produce offspring). In males, the gonads are the two testes, and in females, the gonads are the two ovaries. However, the gonads also produce a variety of hormones, including the female sex hormones: oestrogen and progesterone; and the male hormones including: testosterone and androsterone. This brings us to the question "Do the gonads only have a reproductive function?" The answer is no. They also play pivotal roles in the maintenance of body muscle and bone growth, as well as reducing body fat.

 

We encourage you to research this topic well before making this difficult decision and recommend looking at different types of sterilisation for both male and female dogs. We also encourage you to consider the age at which it may be best to sterilise a dog from a health perspective. The points for and against desexing male and female dogs below do not refer to behavioural or population control, but rather, other less commonly considered facts.

 

Both male and female gonads produce oestrogen. If the gonads (testes or ovaries) in either sex are removed, this hormone is no longer produced. Oestrogen plays an important role in bone growth and development. Prevention of oestrogen production in immature dogs can cause the growth plates to remain open. Continued growth can cause abnormal bone structure, resulting in irregular body proportions.

 

Male and female dogs neutered at an early age are more prone to hip dysplasia and cruciate ligament injuries.

 

Male Dogs:

 

On the positive side for neutering male dogs:

 

• eliminates the small risk (probably <1%) of dying from testicular cancer

• reduces the risk of non-cancerous prostate disorders  

• reduces the risk of perianal fistulas  

• may possibly reduce the risk of diabetes (data inconclusive).

 

 

On the negative side for neutering male dogs:

 

• if done before 1 year of age it significantly increases the risk of osteosarcoma (bone cancer); this is a common cancer in medium/large and larger breeds with a poor prognosis.   

• increases the risk of cardiac haemangiosarcoma by a factor of 1.6

• triples the risk of hypothyroidism

• increases the risk of progressive geriatric cognitive impairment

• triples the risk of obesity, a common health problem in dogs with many associated health problems

• quadruples the small risk (<0.6%) of prostate cancer  

• doubles the small risk (<1%) of urinary tract cancers.  

• increases the risk of orthopaedic disorders

• increases the risk of adverse reactions to vaccinations.

 

Female Dogs:

 

On the positive side for spaying female dogs:

 

• if done before 2.5 years of age, greatly reduces the risk of mammary tumours, the most common malignant tumours in female dogs (but only 30-50% of these are malignant & the prognosis is usually good.

• nearly eliminates the risk of pyometra, which otherwise would affect about 23% of intact female dogs; pyometra kills about 1% of intact female dogs

• reduces the risk of perianal fistulas  

• removes the very small risk (≤0.5%) from uterine, cervical, and ovarian tumours .

 

On the negative side for spaying female dogs:  

 

• if done before 1 year of age, significantly increases the risk of osteosarcoma (bone cancer); this is a common cancer in larger breeds with a poor prognosis   

• increases the risk of splenic haemangiosarcoma by a factor of 2.2 and cardiac haemangiosarcoma by a factor of >5; this is a common cancer and major cause of death in some breeds

• triples the risk of hypothyroidism

• increases the risk of obesity by a factor of 1.6-2, a common health problem in dogs with many associated health problems  

• causes urinary “spay incontinence” in 4-20% of female dogs  

• increases the risk of persistent or recurring urinary tract infections by a factor of 3-4

• increases the risk of recessed vulva, vaginal dermatitis, and vaginitis, especially for female dogs spayed before puberty

• doubles the small risk (<1%) of urinary tract tumours

• increases the risk of orthopaedic disorders

. reduced lifespan

• increases the risk of adverse reactions to vaccinations.

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Should you choose to desex your dog, there are options/procedure types regarding the sterilisation of both male and female dogs. It is possible to leave the gonads that produce sex hormones functional, while still sterilising the dog. There may be considerable health benefits in pursuing this option with your vet.

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