Should I neuter my pet?

Initiatives such as World Spay and Neuter Day, which ran last month, were originally set up for population control. But we now know there are many, many other advantages to pets in being neutered (yes, honest!). In this blog, we’ll explore the main advantages, and look at the reported disadvantages, of neutering your pets.

Advantage 1 – Population Control

Dog and cat overpopulation isn’t just a problem in Eastern Europe and the Third World, it’s a major issue here in the UK. When you remember that dogs are 15 times more prolific than humans – and cats can have 3 times more offspring even than dogs! – the risk of a population explosion is very real. There are tens of thousands of unwanted dogs and cats in the UK – by allowing our animals to breed uncontrolled, we add to that problem. Remember, in 7 years, 2 cats could have up to 40,000 descendents in theory – the only reason we’re not up to our eyeballs in kittens is because disease and starvation thin them out. Not a nice way to control population, compared with a safe surgical operation under anaesthetic and with pain relief afterwards.

Advantage 2 – Behavioural Changes

Entire (i.e. non-neutered) animals have a number of behavioural traits that we often find unappealing. Most of these are driven by the sex hormones testosterone (in the boys) and oestrogen (in the girls). In particular, we think of…

  • Roaming – male dogs and cats will roam over long distances to find females who are in season. This puts them at risk of becoming lost or injured.
  • Loss of training – similarly, a bitch in heat will frequently “forget” learned commands and tricks and go looking for male attention…!
  • Aggression – males tend to fight other males over mates, especially cats, but potentially dogs too. HOWEVER, see below…
  • Calling – when in season, entire female cats shout and “call” for a mate – this is noisy and may even be interpreted as “pain”.
  • Spraying – entire male cats often spray the house; less so females; and neutered cats rarely do so at all.
  • Sexual behaviour – entire males, especially dogs, often get… overexcited. They relieve this tension by humping and mounting (other dogs, their owner, visitors, furniture… whatever is available!). This is not generally considered polite behaviour.

Advantage 3 – Reduced Disease Risks

The sex hormones made in the testicles and ovaries predispose dogs and cats to a wide range of diseases; remove the organs, remove the hormones, reduce the risks. The big ones are…

  • Mammary tumours – spaying before the first season reduces the risk of breast cancer in bitches by a factor of 200, although the protective effect gets less the later it is done.
  • Pyometra – this infection of the uterus is a potential killer, and some studies suggest that up to 50% of entire bitches will have a pyo at some point in life. Once neutered, however, the risk goes down to essentially zero.
  • Testicular tumours – no testicles mean the boys get no tumours!
  • Prostate disease – the prostate gland is driven by testosterone; after neutering, it shrinks away almost to nothing. As a result, diseases such as Prostatic Hypertrophy, Prostatitis and Prostatic Abscesses are almost unknown.
  • Anal Cancer – specifically, cancer of the circumanal glands, which is rare in neutered dogs.
  • FIV in cats is spread mainly by fighting – neutered cats are at a dramatically reduced risk.

Advantage 4 – Longer Lifespan

Overall, if you take everything into account, research shows that neutered male dogs live 14% longer, and female dogs 26% longer. Meanwhile, cats of both sexes would be expected to live 3-5 years longer if neutered at an early age.

You may read a lot about possible disadvantages to neutering – and it’s true, there is some evidence that there are a few possible risks.

Disadvantage 1 – Tumours?

There is some evidence that neutered animals are slightly more prone to certain tumours, especially osteosarcoma (bone cancer) and Prostate cancer. These risks may be lower if neutered later. HOWEVER, overall, these are relatively uncommon cancers – for example, the biggest increase in osteosarcoma risk that’s been reported suggests that neutering increases the chances of the disease by 0.06%. There have been some reports of an increased risk of haemangiosarcoma (a blood vessel tumour), but this hasn’t been replicated in other studies. On balance, the increased risk of tumours is, in most cases, outweighed by the reduced risk of other diseases.

Disadvantage 2 – Weight Gain

Yes, it is true that a neutered dog or cat needs fewer calories than an entire one. However, this is simple enough to fix – feed them a bit less! Increased risk of injuries to parts of the musculoskeletal system are often reported in neutered animals; however, it seems likely that they are due at least in part to weight gain after neutering. Keep your pet slim, and the risk is very small!

Disadvantage 3 – Increased Fearfulness

In a female, or a healthy, well-adjusted male, dog or cat, this isn’t usually important. However, if you have one who is showing fear-based aggression, neutering will not help. The drop in testosterone levels may make the animal more afraid and therefore more prone to snap.

On balance, we believe that most pets can live a healthier, longer, and happier life if neutered. However, we’d always try and base that decision on an assessment of the dog or cat as an individual – so pop in and see us to talk about it if you’re worried!

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