Personality Traits: Which are Heritable?

The Goodbye Bird

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I'm wondering which personality traits you feel can be bred for and which ones you feel are more or less random and it would be pointless to try to breed for.

The breed I'm going for (Oriental Shorthairs) has a wonderful personality already. They're tolerant of other cats, love to snuggle with each other, and even make cat piles if there are enough of them. They're also famously affectionate to the point of demanding the affection and extremely vocal with a distinctive, often very loud voice. There's nothing I'd want to change about any of that, but I'm curious about what could be added.
 

StefanZ

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What is known for sure, is a good psyche in the stud, tends to give good psyche in the kittens. Ie a friendly and easily handleable stud tends to give friendly kittens...

Otherwise, what is hereditary and what is individual is difficult to say, unless you make controlled experimental large scale breeding, as had been done with these stud behavior.

But if you have say, a nice stud or queen, whom you see has a behavior you want to promote, be sure to use this one in your breeding programme.
Perhaps even if its not totally perfect show exemplar. Being healthy and good enough may be sufficient.
 
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The Goodbye Bird

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Perhaps even if its not totally perfect show exemplar. Being healthy and good enough may be sufficient.
Actually the Heinlein novels about Lazarus Long gave me the idea that I could breed for longevity directly. In the story, nigh-immortals were created because somebody decided to subsidise your reproduction if you had a direct relative who reached a very high maximum age. Obviously you don't want to breed from geriatric cats, but you can keep track of how long a healthy young breeding cat's forebears lived.

What is known for sure, is a good psyche in the stud, tends to give good psyche in the kittens. Ie a friendly and easily handleable stud tends to give friendly kittens...
This runs along the lines of genetic memory being passed through the male.

Baby Mice Can Inherit Fear of Certain Smells From Their Parents
After imprinting those males with a fear of acetophenone, the researchers inseminated females with the scared mice's sperm. The baby mice never met their father, but those sired by a blossom-hating dad had more acetophenone smell receptors. Compared to pups born of other dads, most were also agitated when acetophenone filled the air. This same finding held true for those original males' grandpups.

This means I should handle the king as much as possible.

It also means if I'm somehow encouraging a bad trait, it could actually become genetic. There's as much potential for permanent harm here as permanent gain.
 

Willowy

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Epigenetics and genetic memory are fascinating subjects. I honestly wonder how much they have to do with mental issues in humans.

I think breeding for personality is probably pretty complicated. Looking at humans, personality is inherited to some extent but isn't linear (I think that's the word I'm looking for). Like: my brother has 3 kids, all very different in their personalities. The oldest boy is very much like my dad, but nothing like my brother and only a little like his mother. The girl is very much like my paternal grandmother, but not like either of her parents. The youngest boy is a lot like my mom, and also a little bit like my brother (I guess he had to get one like him eventually!). So, yes, inherited, but not always directly from the parents.

But of course, if you want to breed friendly cats, it certainly isn't going to hurt to choose friendly cats as your breeding stock. And maybe grill the breeder you get them from about their ancestors' personalities.
 

lutece

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I know it's entertaining to think about various theories, but it's also important to focus on the basics:
  • healthy cats,
  • with good temperaments,
  • that meet the breed standard,
  • have reasonable genetic diversity,
  • family history of good fertility and healthy kittens,
  • are not carrying known disease causing mutations,
  • and are not closely related to one another.
It can be difficult enough to obtain breeding cats with all of the above characteristics. Focus on basics first and then you can develop whatever theories you want later on.

If you are serious about your breeding program, I recommend using Optimal Selection Feline to test breeding cats for known disease genes and genetic diversity (which is an issue in the Orientals, it's pretty low on average) and make use of its breeder tool to plan high diversity matings. Genetic diversity is an important part of breeding for life span and health.
 

StefanZ

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Actually the Heinlein novels about Lazarus Long gave me the idea that I could breed for longevity directly. In the story, nigh-immortals were created because somebody decided to subsidise your reproduction if you had a direct relative who reached a very high maximum age. Obviously you don't want to breed from geriatric cats, but you can keep track of how long a healthy young breeding cat's forebears lived.



This runs along the lines of genetic memory being passed through the male.

Baby Mice Can Inherit Fear of Certain Smells From Their Parents
After imprinting those males with a fear of acetophenone, the researchers inseminated females with the scared mice's sperm. The baby mice never met their father, but those sired by a blossom-hating dad had more acetophenone smell receptors. Compared to pups born of other dads, most were also agitated when acetophenone filled the air. This same finding held true for those original males' grandpups.

This means I should handle the king as much as possible.

It also means if I'm somehow encouraging a bad trait, it could actually become genetic. There's as much potential for permanent harm here as permanent gain.
Talking about Heinlein and his SF novels. He had another one where heredetics was mentioned as essential for the plot.
The Thema was, Black is beautiful.
And thus, our black hero, told about his family history. Since about 200 years, they did their outmost to marry as black as they could. (I suppose some of their ancestors willy nilly met some white man whom spoiled their blackness. So to speak. But the net result WAS The ANCESTOR started from a bleakish startpoint, coffe with much milk??... OK, so we are presented with a long chain of successive doing their outmost to marry as black as possible, and held the not so very much black children from marrying (or at least, not marrying into this here family, they could of course marry into other families, no problems).
BUT. 30 years ago they discovered an genetic engineering gimmick which made possible to choose exactly the color of skin of the childs. And thus, our hero and all of his siblings are now pitch black... Exactly as desired by all their ancestors...
They all were proud blacks, but NOW they are black for real... :)


Jokes and SF novels aside.

What Lutece mention, diversity is important, and thus, a too hard selection is a danger.

On a genetic course, the prelector took as an example.
Say, you want long tails in your cats. And thus, dont breed any cats with short nor even medium tails.
You will soon see you had lost many other genes than just the gene for short and medium tail...

Because genes arent totally randomly set. Some are connected, and we dont always know or understand exactly how and why...
So, beware of harsh and radical programmes, unless you know exactly what you are doing!

And or are ready, to get a big amount of leftovers. Ie kittens whom doesnt meet your dreamed off standards.
It may easily become a maze and ethical problems.
 
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The Goodbye Bird

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Traits that go together may have a developmental element or they may simply happen to be in close proximity on the same chromosome.

I selected a breed in trouble on purpose. Cats with less genetic diversity need more breeders. Cats that are outcrossed to some other species entirely (like Savannahs and Bengals) may have their own problems but they have a wealth of genetic diversity.

Now I'm not saying I will inbreed (I won't) but I often think that the health of a breed in trouble could be improved with a bigger focus on genetic testing and a smaller focus on COI. By refusing to inbreed, in a way you're preserving all that recessive genetic nastiness just to get a bigger chance of a healthy individual this time. But you're sort of passing the buck.

Cats in the wild inbreed and bad recessive traits express and get selected out.

We're in a place with a lot of breeds where they don't have good longevity and/or they have a few known problems.

Part of it is that people will breed from a cat of less than perfect health to get better conformity to type. I mean, you have to. The wild selects for exactly one type: Wild type. Every element of the wild type is something that allows a cat to survive better. And the moment you say, I want this trait, so I will pick cat B instead of cat A, where cat A is the one that would have survived in the wild, and cat B is not, you have lost some health. At best you can be neutral and lose survival traits that may not matter to the situation like coat colour.

Once you pick a cat of less than perfect health to breed from, you have already disregarded the whole reason not to inbreed. COI is a calculation that basically gives you a cat's chance to inherit a bad trait we assume the duplicate cat in this one's ancestry carried. Well, once you go ahead and say, alright, this cat has a bad trait and I'm going to breed from it anyway, as far as I see that cat's COI should be 100. It's no longer an unknown. We know it and we did it anyway.

Conversely, if we could know that a cat was perfectly healthy, perfectly clean genetic slate, it wouldn't be a problem to inbreed. Arguably no cat has this and it's a fair point.
 

Willowy

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if we could know that a cat was perfectly healthy, perfectly clean genetic slate, it wouldn't be a problem to inbreed.
Theoretically that would make sense. In reality, there's no way to know if a cat is a perfectly clean genetic slate, and that's probably not even possible for a living organism (like you said). Even if you weed out the obvious/testable genetic illnesses, inbreeding will eventually lead to increased cancer rates and general lack of vitality, to a genetic dead end.
Cats in the wild inbreed and bad recessive traits express and get selected out.
They do but eventually the line peters out without fresh blood. It happens a lot among farm cats. At some point they start to be very sickly with low lifespans and reduced litter size. The population shrinks. New cats move in to fill the void. Fresh blood! The population rebounds and is generally healthier. Then it happens again, over and over. Since fresh blood can never be added to a purebred population, by definition, genetic diversity shrinks with every generation, so if you want to keep things going as long as possible, it's smarter to choose as much genetic diversity as possible.
 

lutece

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Since fresh blood can never be added to a purebred population [...]
Actually, breeders do add outcrosses to pedigreed breeds from time to time, in order to increase diversity. There is no such thing as a 100% "purebred" breed... all breeds have incorporated outcrosses at some point, as part of their development over time. But it's also important to manage diversity within the breed to avoid having to do that too often.
 

lutece

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Cats that are outcrossed to some other species entirely (like Savannahs and Bengals) may have their own problems but they have a wealth of genetic diversity.
Bengals' average genetic diversity is slightly below average for pedigreed cats. A tiny bit of wild species ancestry in the far off past doesn't add a tremendous amount of diversity in itself... breeders had to subsequently do a lot of line breeding in order to develop the breed as we know it today. Even though the Bengal is a popular and numerous breed, that in itself doesn't make the gene pool large, when there are bottlenecks and popular sires in the past.
Now I'm not saying I will inbreed (I won't) but I often think that the health of a breed in trouble could be improved with a bigger focus on genetic testing and a smaller focus on COI.
Almost all mutations with harmful effects are unknown. We only know about a few of them. So, managing genetic diversity is generally a much more important factor for breed health than screening for the (relatively few) mutations that we know about. In fact, it's important not to be too severe in eliminating animals from a breeding program even if they carry known disease mutations... breeders need to carefully and gradually eliminate carriers over time without losing too much overall diversity.
You might enjoy some of these articles from the Instiute of Canine Biology (they also have courses you can take).
 

lutece

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Part of it is that people will breed from a cat of less than perfect health to get better conformity to type. I mean, you have to. The wild selects for exactly one type: Wild type. Every element of the wild type is something that allows a cat to survive better. And the moment you say, I want this trait, so I will pick cat B instead of cat A, where cat A is the one that would have survived in the wild, and cat B is not, you have lost some health. At best you can be neutral and lose survival traits that may not matter to the situation like coat colour.
The natural domestic cat doesn't have a single "wild type." There is a fairly wide range of body and head types that all work just fine for health and survival in the domestic cat's natural environment (domestic cats aren't really "wild animals" that "must survive in the wild"). Physical structure can start to be an issue when breeders intensify specific extreme features. For example, I have read that very small and deep-set eyes in European Maine Coons can predispose the cat to entropion (eyelid turning inward, causing the lashes to irritate the eye). However, that type of eye placement is really not necessary for the breed standard... you can breed beautiful Maine Coons with normal sized, normally positioned eyes.

Some breed standards are more challenging for producing healthy cats. Breeds with extremely short faces can have issues in both dogs and cats... when breeders are very careful they can reduce the impact of these features (for example, breeders can select for symmetrical faces with proper bite, and large nostrils to reduce breathing issues) but it can be a challenge to work with such breeds and it does raise ethical questions. Other breeds such as Scottish Fold and Manx are built around genetic mutations that have inherent health issues; I know several Scottish Fold breeders who have switched to producing only straight eared cats for this reason. But most cat breed standards do not require breeders to produce a cat with physical structure that is opposed to health.

Wild felines also have a wide variety of features, head types and body types. There is no single type of wild feline that is "the one that survives in the wild." Both wild and domestic felines can have a range of features and remain healthy.
 

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Interesting discussion! I live in an area where spay and neuter programs have been very successful, so there is a lot more people looking for random bred kittens than are getting born. So I ended up with a couple diluted hybrid Savannah kittens, and have done a lot of thinking about how we define animals as either domesticated or wild. One aspect of this is when animals begin being selectively bred to have traits we find pleasing as humans, but that do not necessarily contribute to their longevity and health. Random bred cats are really an unusual animal because they seem to have evolved, mostly through natural selection, to be wild animals that benefit from intimate relationships with humans, but up until very recently, unlike any other domestic animal they were free to come and go as they please, choose where they lived, and were free to choose what they felt was best for them. From what I have read, the main genetic difference between our family members who are cats, and their still wild cousins, is a few genes that make them more relaxed and tolerant of humans. I think I have read that every other animal we have domesticated is by nature a herd, flock or pack animal, and we simply insert ourselves into this hierarchy as boss, which herd animals find acceptable. I find it totally intriguing that a supposedly solitary hunter managed to somehow evolve such a complex and deep social sensitivity that enabled it to form such strong bonds with humans, but it makes sense that cats that earn human love probably have better chances of surviving and reproducing. Or they used to... I realize too many kittens from random bred cats is the most immediate concern in most parts of the world, but I also worry we may be driving the amazing evolution of social skills we see in cats backwards, by spaying and neutering all the random bred cats that are loved and easiest to live with (or spaying and neutering the ones that have no home, but easiest to catch) and breeding more for a look than the capacity to form a deep bond. So I am glad to see a discussion about the importance of breeding for temperament, and how this might be continued, but without encouraging the birth of unwanted kittens!
 

lutece

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[...] I also worry we may be driving the amazing evolution of social skills we see in cats backwards, by spaying and neutering all the random bred cats that are loved and easiest to live with (or spaying and neutering the ones that have no home, but easiest to catch) and breeding more for a look than the capacity to form a deep bond.
Show breeders typically do select pretty strongly for temperament, not "just for looks." Most of us live with our breeding cats, and select cats for our breeding programs that are a pleasure to live with. Also, even though most breed standards don't mention temperament, cats of all breeds must have good temperaments to do well in shows. Top winners generally have outstanding temperaments, as they must be able to tolerate traveling and being shown extensively, they must be friendly with strangers, and relaxed and playful in a variety of environments. Judges like to put cats in their finals that have a lot of charisma and put on a great show for the spectators.
 

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I had not thought of that as a factor, but it makes sense that that would help!
 
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The Goodbye Bird

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There is no single type of wild feline that is "the one that survives in the wild."
Maybe I was trying to far oversimplify the issue to an absurd case in which only one kitten out of any given litter will live. That's not the case. But one kitten will grow up to have more reproductive success in the wild than the others. So picking any cat other than that one will have effects.

Think of it in terms of hit points. HP = health, but in a much more general sense than simply resilience to physical damage. In my analogy it's more a measure of the ability to survive and reproduce in its wild environment.

Every feature on a cat you pick out of the wild contributes at least 1HP. The shape of its snout helps it bite optimally. The little ridge of face fur on a tiger helps it spread its scent, hold its territory, and ultimately breed more.

For every feature we breed for that is out of the range of wild type, there is some reason the wild type does not possess that feature.

So if the HP range of the kittens in a given litter is 56, 54, 51, 28, and we select any cat to breed from other than the 56HP cat, health has been lost. Sometimes it's in ways that don't matter like having a white coat. But we also don't know exactly how those 2HP have been lost when we select the seemingly perfectly healthy second cat, we just know they have been lost somehow because the best survivor is that first cat. So we made an unknown sacrifice to get a trait the second or third cat had. Well, it was probably nothing, we think, something like coat colour that doesn't matter to its longevity. Then before we know it we have cats with only 10HP and they're not living as long. Some few of those sacrifices weren't benign.

In some cases the sacrifices are known, like the breathing issues and short snouts. When it's known, to some degree you can help it, just as you described with selecting for bigger nostrils.

The key then is to always know exactly why the wild type range is like it is - in other words, to figure out exactly where those 2HP went.
 

lutece

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But one kitten will grow up to have more reproductive success in the wild than the others. So picking any cat other than that one will have effects. [...]
There are two problems with this viewpoint.

1) There just isn't a single perfect / optimal shape for a cat. Look at felines all around the world, both wild and domestic. There is lots of variety... they do not all look the same. There are plenty of ways for noses and ears and eyes to be shaped that are all just fine.

2) We don't need, or want, to optimize our cats for "reproductive success in the wild." That doesn't necessarily lead to the best health, longevity, and happiness for the individual cat. For example,
  • A female cat that has early and frequent heat cycles and lots of litters might be really well adapted to producing lots of offspring "in the wild"... but not necessarily well adapted to having a long, healthy and happy life.
  • A male that has really stinky pee and is aggressive around other males might be well adapted to producing lots of offspring "in the wild"... but not necessarily well adapted to happily living with humans and other cats.
Cats have been living with humans for thousands of years. They can do okay as feral cats, but this isn't an ideal situation for the domestic cat. Cats are not wild animals, and we don't want them to be wild animals. We can, and should, provide a better life for our cats than that.

We want to raise cats that are healthy, happy, and well adapted to the human environment in which they live. So it's most appropriate to measure the success of our breeding programs by the health, longevity, and happiness of cats in their human homes.
 

Willowy

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a measure of the ability to survive and reproduce in its wild environment.
I think you may be oversimplifying a little. In many cases, natural selection is pure chance/luck. Yes, those with traits not suited to the environment won't survive, but for those with acceptable traits, sometimes what it comes down to is one ran right and one ran left, and the predator could only go after one of them. But that doesn't mean running left is better.

And cats being around humans affects their survival traits too. "Pretty" ferals/farmcats are more likely to be fed and protected by humans than a plain brown tabby, even though little African wildcats (what domestic cats are descended from) are all tabbies. So the traits that determine survival may not be those that would help "in the wild".
 
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The Goodbye Bird

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I think you may be oversimplifying a little. In many cases, natural selection is pure chance/luck. Yes, those with traits not suited to the environment won't survive, but for those with acceptable traits, sometimes what it comes down to is one ran right and one ran left, and the predator could only go after one of them. But that doesn't mean running left is better.
Right, but overall, you get a cat that is perfectly adapted to survive in its environment. Some chance/luck doesn't invalidate Darwin.

When you select any cat other than the one in the litter with the maximum survivability, you lost a few HP. Sometimes we know where they went and we can say with confidence that coat colour is not going to impact a cat's longevity in captivity even though it would in the wild. Sometimes, however, we may not know why the wild prefers a different cat than the one we selected and the HP lost might or might not impact the cat's vitality directly.

There just isn't a single perfect / optimal shape for a cat.
Clearly, cats that are shaped much as Orientals can be perfectly healthy because a serval is shaped about like that. It's gracile with large ears, though the head isn't exactly wedge-like.

Nature would only allow the change in shape in a way that didn't remove HP. Therefore, there must be such a way.

I'm just not positive the change in shape has been achieved in the same way.

We don't need, or want, to optimize our cats for "reproductive success in the wild." That doesn't necessarily lead to the best health, longevity, and happiness for the individual cat.
Of course not, but what I'm saying is that some traits that do help optimise the health and longevity of the cat are baked into any cat that you pick out of the wild, and if you change that cat, you may be sacrificing those traits without realising it.
 

Willowy

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Clearly, cats that are shaped much as Orientals can be perfectly healthy because a serval is shaped about like that. It's gracile with large ears, though the head isn't exactly wedge-like.
Servals are perfectly suited for their environment. They wouldn't thrive in a Northern climate. Ferals/farmcats in Northern climates usually have cobby bodies, small ears, thick fur. So the ideal body shape for a cat can't be generalized; it's highly dependent on climate and other environmental variables.

It also may not be useful to compare domestic cats to other species, as some may have adaptations that domestic cats don't.
 
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The Goodbye Bird

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So the ideal body shape for a cat can't be generalized; it's highly dependent on climate and other environmental variables.
My point is just that you don't know what else you may be doing when you change the shape.

If (just hypothetically) there was a gene that gave a cat double body length but halved its lifespan, Nature wouldn't make a serval that way but we can't say we don't have something like that floating around in our gracile domestic cats.

A concrete example of what I'm talking about is size. Large animals live plenty long in the wild, but if we take a medium animal and breed it bigger we tend to lose lifespan. If we wanted a huge moggie the size of a Florida Panther, we might be able to do that, but it would probably have all those lovely Great Dane issues and live for about eight years.
 
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