Are there any efforts underway to select for longevity? Is it even theoretically possible? It should practically be possible with sperm/egg storage and artificial insemination. It may not be economically feasible for creating a dog breed though I suppose.
Rat breeders (yes they exist) breed for longevity and resistance to cancer. I’d imagine all breeders breed for longevity, although it might not be the top priority. Certainly breeding for health would have that effect. I’ve heard of Great Dane breeders breeding for longevity as well, since the large dog breeds tend not to live very long.
Do you know how breeding for longevity is accomplished? Do they breed individuals whose ancestors had longer lives more frequently?
Good animal breeders often have a good feel for genetics even with no formal training. They will recognize features and confirmation traits that these long lived animals have and be able to spot them in younger dogs even if they didn’t come from the exact same heritage. Bird dogs have a fairly long life span of about 16 years compared to some of the small dogs that can hit 19 and 20 fairly common. I think a dog that lives along time and is a working dog has time to build up a reputation and would be attractive to use a breeder.
There are people like Michael Rose who are doing this exact thing, only in fruit flies, simply by breeding the longest living flies from each generation. According to wiki they’ve managed to quadruple the flies’ lifespan. Obviously it’s much easier to do this in something with as short a generation time as flies, but no reason why you wouldn’t be able to do it in other organisms.
That’s the difficult thing about selecting for longevity - after you’re sure you’ve got the trait, your animal is likely to be post-reproductive.
I don’t know about HoneyBadgerDC’s assertion that breeders will recognize physical traits linked to longevity - do you have a cite? So many factors contribute to life expectancy, I can’t see how this could be possible.
Like with any selective breeding programs, choosing the correct foundation stock is only the first hurdle - culling subsequent stock which doesn’t meet your criteria is also vital. Often, breeders have to weigh an animal’s strengths and weaknesses. For many breeders, choosing physical traits for “type” is the easiest characteristic to assess, and, easier to assess against a standard.
As miss elizabethsays, simply excluding genetically unhealthy animals will increase a line’s average lifespan. And health testing (e.g., hip/elbow dysplasia, Fanconi syndrome, etc) is becoming more and more the norm for dog breeders.
Well, its tricky because usually by the time you know how long the animal will live, it hasn’t been useful for breeding for a little while. For example, female rats are prone to getting mammary tumor and dying young, but by the time they start to get those problems they are no longer fertile. So you use a lot of record-keeping, and have to be willing to stop breeding from a certain line, even if they are quite pretty or have other traits you want, if you can see they are prone to dying young. I mean, beyond that it’s like any other breeding; you breed from the stock that has the traits you want (in this case a family history of longevity, or perhaps a family history or not getting cancer) and do not breed from stock that has traits you don’t want. And, over generations, it makes a difference.
You got some good answers I didn’t see already. Anyway, just as a general point, I think a lot of people don’t fully appreciate the amount of work and record keeping that goes into (good) breeding. It’s an incredibly tedious hobby, with very little payoff, since it takes generations to really notice a change. That’s why people say reputable breeders never make any money; if you’re really trying to improve the breed its far more work than profit. But, if you truly love the animals, it’s worth it, because you’ve contributed positively to their genetic heritage and also your records can be used by future breeders.
Thanks for that cite. I should have expected fruit flies 
I agree, but that’s not an insurmountable obstacle, especially not today.
This is not necessarily true though is it? I mean, it seems to make sense, but I wouldn’t assume it. ETA: Ack. sorry, I didn’t catch the word “average”. Yeah, that’s true, but not particularly what I’m interested in.
Yes, I agree it wouldn’t be simple, particularly not with traditional breeding methods. Which is why I wanted to know if someone was doing specifically this. It turns out they are, at least with fruit flies.
They really are also doing it with rats. I mean, I could try to find you cites if you really care, but if you google rat breeding there’s plenty about it. I’d say for most good rat breeders it’s the #1 concern. I know we have a member on the board who is a rat breeder, Feyrat. Maybe she’ll see this and respond.
I did google rat breeding for longevity, but couldn’t turn anything authoritative up easily. If you know of a good resource, it would be good if you could post it. It should be interesting to see.
It’s been awhile since I read up on it (my rats died about 6 months ago, which means I was reading about it about 3 years before that) but I’ll see what I can find.
Some horse breeds are known to live longer than others, including Arabians and Appaloosas. I don’t think this was a directly bred-for trait, but rather a side effect of a trait they did breed for: endurance. A horse with a more efficient heart/circulatory system and respiratory system is just going to live in better health, longer.