It is a fact that women live longer than men. All over the world, wherever data on human health is collected, the trend is the same. Those with XX chromosomes rather than XY, have a biological advantage when it comes to clocking-up birthdays.
Is the same true for dogs?
Does the gender of your pet dog pre-program how long they will live? The answer is ‘Yes’, but also ‘No’ depending on whether they are neutered or entire.
This article answers dogged questions such as:
- Which gender lives the longest?
- What difference does desexing make?
- Are causes of death different for females and males?
- What is the biggest single factor that influences a dog’s lifespan?
The Trend for Female Seniors
It isn’t just people where the females live longer than males. Studies show this is also the cases for monkeys in the wild and for Old World Apes. And if you thought th elater might be down to males apes being killed in fights or protecting the females, think again. Statistics around lab rat life expectancy, bears out this same trend. Rats that receive the same diet, same medical attention when they get sick, and live in the same environment, can expect the females to live longer
An Exception to the Rule
Biological scientists agree that for the majority of mammalian species, females live the longer. However, one species does buck this trend…and that species is the meerkat.
OK, you say, so I can stop reading now. If the majority of mammalian species have more females reaching big ages than males, then the same must apply to dogs.
Well, yes… and no. Read on to find out factors that buck this trend.
Dogs are a Special Case
Tall or short, most people are roughly similar in size. This is not the case for dogs.
Our canine companions come in a wide variety of shapes and sizes (or breeds!) from the diminutive tea-cup Chihuahua to the giant Great Dane. And when it comes to lifespan, size matters.
- Small breeds live longer
- Large breeds age more rapidly
This average life expectancy varies by 50%, from the long-living breed to those with the shortest lifespan.
Dogs have Four Genders
Before moving onto the meat of the issue, here’s a curve-ball. Dogs have not two but four genders. That is:
- Female entire
- Female neutered
- Male entire
- Male neutered.
And the interesting thing is neutering DOES have an impact on life expectancy: But for better or worse?
Dog Lifespan League Table
- VetCompass: Gathers data by analysing the computerized records of UK, first opinion vet practices. This follows all pets from puppies (or kittens or guinea pigs or rabbits ) to end-of-life to give an invaluable overview of their health.
- Veterinary Medical Database: This collects data from member hospitals of the North American Veterinary Colleges. This is a slightly less ‘real’ slice of the pet population since it looks at referred animals with health problems.
Drum roll: The gender with the longest average lifespan is…neutered females.
But there’s a twist, because entire females (those that still have a womb) have the shortest lifespan.
OK, to make things clear:
1st place for longest lifespan: Neutered females
2nd place: Entire male dogs
3rd place: Neutered male dogs
4th place: Entire female dogs.
The prize for being in first place (neutered females), is a clear six-months increased life expectancy than the second placed dog (entire males.) Of course, this is an average, so there will be entire males that live longer than neutered females, and entire females that outlive entire males…but rule of thumb is neutered and female is a winning combo in the lifespan stakes.
Yet Another Twist in the Tale
Another quirk thrown up by the data is that young male dogs are more likely to meet an untimely end, than females.
Although we can guess at the reason (perhaps they run off more or get into fights) in truth, this needs more research to be sure.
Causes of Death
Do the same conditions kill male and female dogs, or do they differ?
Actually, the different genders carry different risks. The most common conditions that impact on lifespan are:
- Female dogs: Endocrine disorders such as Cushing’s disease or diabetes mellitus (sugar diabetes)
- Male dogs: Heart disease and blood-related disorders
But this is where it gets confusing, because both desexed males and females carry a higher risk of getting cancer during their lifetime….and yet neutered females have the greatest lifespan. This takes a bit of getting your head round. Again, the implications of this need further research.
The Take Home Message
Should you choose a male or female puppy if you want a dog to live as long as possible?
By the law of averages, a neutered female dog has the greatest probability of a long life. But the story is more complicated than this and you can influence events. For example:
- Take great care of young male dogs (remember their increased risk of an early death.) Time is well-spent in reward-based obedience training and avoid leaving them outside unattended. If they avoid meeting an untimely end, who knows, they may be one of the longer living males to outdo the females.
- Whether a female is neutered or not places them at opposite ends of the lifespan expectancy league. Yes, neutering can have implications (which require a separate blog post!) but for the majority of female four-leggers it pays off to neuter
The Biggest Factor of All
But when all’s said and done, the factor with the biggest influence on life expectancy is breed! Giant breeds have a single figure life-expectancy whilst small dogs off live well into their teens. So there’s a lot to be said for keeping your pet healthy but just getting on with life and not over-thinking things!
If you would like to know more about the effect of gender on canine lifespan, follow the link to Do Female Dogs Age Differently than Male Dogs? from the Journal of Gerontology.