Do cross breeds live longer than pure breeds?

[BikeRunSki]

Apologies in advance if I use any terminology wrongly, I’m not really a dog person.

DM lives by herself (widowed for 25 years), currently with only her dogs for company, 250 miles away. Fortunately, we saw her at Feb half term! Anyway, she adores her dogs, especially the older one. They are both black lab/springer spaniel crosses, both girls and are 13 and 9. The 13 year old had one of her front legs amputated when she was 5, because she broke it and it didn’t heal well.

The 13 year old is really getting quite doddery, but DM is convinced that she has “a good few years left in her yet” because she’s not a pure breed. Is this right? I’ve googled (I know!) life expectancies for Springers and Labs and both say 12-14 years, which is how old she is now. I‘m really hoping DM is right and this is not wishful thinking on her behalf. I’m worried the dog will due during lockdown and no one will be able to comfort her. Maybe I am being irrational because I can’t visit?

Yes because of inbreeding.

Still a well bred pure breed can be healthy too.

It's so hard that they live for such a short time. My dog is only 4 and I already dread him going.

I have 4 rescues, the springer x collie has never had an ill day in her life, nearly 10 and seems like a puppy. My 8 yr old staffy has had cancer, I lost another staffy at 7 to cancer; she was a blue which are hugely inbred and have countless health issues.

Yes x breeds healthier as pure bred dogs are so inbred.

Not really the answer to your question but my friend has a pure bred Springer who is at least 14 years old. No one knows exactly as the poor dog had been abandoned and the rescue place said they thought the dog was between 1-2. Anyway the dog is very healthy doesn’t look like it’s on it’s last legs or anything.

Ah this is all good to know!!

I think I am probably inventing worries fir nothing, as displacement for not being able to visit this BH weekend.

There's a bit of a myth of hybrid vigour sometimes - if you take (for instance) a cross of a Cavalier and a French Bulldog, both breeds are prone to health problems and could pass on problems from both sides of the family to pups.

My own young crossbreed has dodgy front legs, which both the vet and I are agreed is probably the result of crap breeding (he's a rescue).

A Heinz 57 mongrel of many types may be healthier on average, but you don't get so many of those about nowadays!

A well bred dog of a breed that isn't riddled with health problems can often be longer lived than a cross anyway

A properly bred pedigree dog from healthy, not inbred stock which has been health screened for diseases known to that breed is likely to be healthier than a crossbreed.

At 13 her dog is probably nearing the end.

"Hybrid vigour" can be a thing but it's not 100% and not guaranteed because genetics doesn't work like that, which is why the inheritance of characteristics is described in probabilities and not absolutes.

You might get a cross with 100% of the 'good' characteristics of both breeds, 100% of the 'bad' ones or pretty much any percentage mixed good and bad. The same applies to the genetic characteristics of the parents of pure breeds. Then if course there's the modes of inheritance: dominant, recessive, etc., etc..

TL;DR version: yes and no.

13 is a pretty good age and it seems the dog has been very well cared for. Her being doddery may be 'just' old age, or she may have soreness somewhere; arthritis perhaps due to joint wear on her remaining limbs. Hopefully the lockdown won't go on too long and you could get this checked, most vets do a 'veteran' health scheme to help with the usual challenges.

If she's not already on them your mum might consider a supplement or two for the dog's joints and general well-being?

Ah, the dogs are very well loved, and I bejice Old Hoppalong has “old girl supplements” and routine check ups. I’ve never been concerned about her before, but an off the cuff remark by DM a few days ago about her “girls” giving her structure to her days, and the older one being 91 in dog years alarmed me. But I think I’m just exaggerating small worries because of the situation.

On average yes, mixed breeds do tend to live longer than pedigrees for the simple fact that on average they have greater genetic diversity than pedigrees which has a major effect on lifespan. It's no coincidence that some of the recognised breeds with the shortest average lifespans are also some of those with the shallowest gene pools.

Obviously it's not a guarantee and there are other factors to consider (size in particular clearly has an impact on life expectancy) but dogs with greater genetic diversity are likely to have a longer lifespan and fewer health issues than ones with higher levels of inbreeding.

This article has some very interesting information about the negative effects of inbreeding on lifespan.

On average, crossbreds and mongrels live longer than pedigrees. They have less risk of having two copies of deleterious recessive genes, tend to have better immune systems, and are generally more successful at producing puppies (higher levels of fertility). They are also less likely to have the sort of extreme morphology that results in major health problems (e.g. long back causing problems for dachshunds, lack of muzzle causing breathing problems for French bulldogs).

I’ve kept & showed, bred a few litters, pure breed terriers all my life, Cairns & Skye Terriers. All except four have lived well into their teens, around 16 years. Five reached 18, two were 19 & one had just turned 20 when she died. Currently I’ve got three teenagers.

Regarding gene pools, I’m no vet, just an experienced breeder if many years, Skyes are right at the very top of the At Risk British Native Breeds, one of the reasons I keep them as well as loving the breed so have one of the smallest gene pools. My 20 year old was a Skye as was one of the 19 year olds.

Mongrels are much cheaper to insure, which neatly answers your question.

Yes it is mostly true. I have one of each.
My mixed-breed is 11 next and she is the picture of health, at the last vet checkup she said she'd never seen a dog in such good shape for their age. She likes the slow life now but she would walk and run for hours and hours if she had the chance.
My pure-breed was in the vets more times in his first couple of years than the older has been in her entire life. As awful as it sounds, I do think he'll 'go' first despite being 5 years younger than the other.

My two pedigree Yorkies lived to 18 and 19. It depends vastly on the breed and how they're cared for.

Small dogs usually live longer than large dogs of any type.

Like others have said, it really depends on the dog type but based on the age of mine own familys dogs (currently got a 15 year old) I think you are right

Relatives had a teacup yorkie that lived till 21! I think the little light breeds have less pressure on their heart that just keeps them going. Another relative had Victorian bulldog that sadly passed away at 7 (but was expected). The bully also had some breathing problems linked to short muzzle and was blind in one eye, also some deafness (white dog). Both were pedigree but I think in some breeds the physical attributes have been 'breed into the breed for the standard'. Which is a bit sad really as a healthy dose of non 'kennel club standards' would probably help some breeds out a lot. Obviously much depends on the actual dog too though as all general illness can strike on top of the 'norms'. German sheperds for example are well known for the back end going during later life.

I'd also advise her to watch the dogs weight, it's really easy to let it creep and if the dog is missing a front limb it really can't afford to carry extra baggage.