Is orthopaedic hindlimb pathogenesis in Maine Coons partly due to their gait?

-

The title is a little bit complicated, but it is based upon a study which is even more complicated 😢😎! Researchers asked the question as to whether the well-known hindlimb health problems of the Maine Coon cat namely hip dysplasia and patella luxation were due in part to the way the Maine Coon walks i.e., their gait and the forces encountered.

Polydactyl paws- Maine coon Tootsie
Polydactyl paws- Maine coon Tootsie. Image by Valley Girl on Flickr.

We know that these diseases are inherited because, I would argue, of sloppy breeding practices which are accepted by the cat associations. But are they exacerbated by the gait of the Maine Coon?

The researchers compared the "ground reaction force" and ancillary forces of Maine Coon cats with those of regular domestic cats. 

"Ground reaction force" (GRF)means the force applied to the feet of cats by the ground on which they walk. Or "the force exerted by the ground on a body in contact with it." As I understand it GRF changes as the cat walks.

More technically, (and this probably won't interest anybody 😃) the "parameters evaluated were peak vertical force (PFz), vertical impulse (IFz), time to PFz (TPFz), step length (SL), paw contact area (PCA), stance phase duration (SPD) and symmetry index (SI) for the fore- and hind limbs".

In conclusion, once they had normalised these forces i.e., they had taken into account the size and weight disparity between Maine Coon cats and other domestic cats, they found that there was no difference or more accurately they "could not confirm differences".

Accordingly, the authors of the study were driven to "conclude that genetic or other causes may be involved in orthopaedic hindlimb pathogenesis seen in MC cats more often than in other breeds".

In other words, it looks as though the sole reason for hip dysplasia and patella luxation in Maine Coons is the inheritance of genetic mutations which import these diseases into offspring from, ultimately, foundation cats in breeding lines which should have been culled.

P.S. An interesting thought is whether polydactyly exacerbates these hind limb issues.

P.P.S. If the reader is a scientist, please feel free to comment and ellucidate!

Comments

Post a Comment

Please share your Maine Coon experiences.

Popular posts from this blog

The extreme Maine Coon face

-
Image
This is an example of extreme breeding. This is a Maine Coon but this cat is an extreme and rare example of this breed. This is not the way they look normally. This face is almost like an aggressive robot with the piercing eyes and the huge muzzle.  Or like a lion's head. The head looks enormous and very heavy. It looks unreal. But it also looks very impressive.  And purchasers like impressive-looking domestic cats. But this not the face of a Maine Coon that wins cat show competitions as it does not fit the breed standard as accurately as the more moderate winners (see below).  In fact, the CFA standard is clear in that the cat should have a balanced appearance although this cat was not bred under the CFA breed standard as I understand it (see below).  Click here for more on the kind of MC which wins at shows . Maine Coon selectively breed to have an extreme face. Image in the public domain. And the Maine Coon is meant to be a large cat, the largest domestic cat b...
Read more

Maine Coon Size - this is a huge one!

-
Image
  Enormous Maine Coon with a head bigger than the person holding him. Pic: in public domain. Maine Coon size is very important to both breeders of this cat and the public. I sometimes think that the public is more obsessed with Maine Coon size than the breeders are. The bigger the Maine Coon the better. There is a fascination about it and I confess that there is nothing much more impressive than a huge Maine Coon. They've been bred like this through selective breeding but please remember that they weren't always like this. The original Maine Coons were regular farm cats in the state of Maine in 19th-century and before. They were robust, rugged, medium-longhaired moggy cats but impressive nonetheless. Their impressiveness led to breeders deciding to breed them which in turn led to the breed being accepted by the cat associations and then to win cat shows and become perhaps one of the most famous breeds in the world. The breed standard for the Maine Coon as provided by e.g. Cat F...
Read more

Average lifespan of Maine Coon cat

-
Image
How long do Maine Coon cats live for? What's the average lifespan? Do they live shorter lives than the average random-bred family cat? These are difficult questions to answer accurately. In fact, I don't think we can answer them accurately because nobody has been counting. Nobody has a database or carried out a full-blown survey and therefore you will read anecdotal evidence i.e. statements by breeders or people who think they know the answer and these answers get repeated on the Internet. I am not sure that they are accurate. Picture of a Maine Coon who looks like a middle-aged man. Photo: Pinterest. My research indicates that people believe that Maine Coon cats live between about 10 and 15 years old. Some may live longer than that and some may live shorter lives. One well-known Maine Coon, Rubble, lived for 31 years and was at one time the oldest domestic cat in the world. But there will always be exceptions and this article is about the mean or the average although these ...
Read more

Comparison of a black smoke Maine Coon at 6 weeks and 6-years-of-age

-
Image
This is a cross-post as the image is so damned good. It is amazing because the cat is amazing. To put the same cat at different stages of their life in the same photograph is a nice idea especially with this Maine Coon (MC) who has an amazingly heavy face. It is so mightily masculine to be almost unbelievable. He has a priceless expression on his face too. Very serious compared to the innocence of his face when he was 6 weeks old. He looks a bit coy when 6 weeks old and a slightly grumpy middle-aged man when 6 years old. Comparison of a black smoke Maine Coon at 6-weeks and 6-years-of-age. Image in pubic domain. No doubt he is huge too. You get a clear sense of that in the image. There is a serious and less impressive side to this image. It's the backstory that people don't really want to read about and discuss or in fact do anything about: heart ( HCM ) and joint disease. The bigger and heavier the MCs are the more predisposed to heart disease they are. Here is the posts on...
Read more

Are Maine Coons illegal in some countries, states or territories?

-
Image
One Maine Coon website asks if Maine Coons are legal? My initial response was that it is a bizarre question (second thoughts below), but I'll answer it in my way. I say that it is a bizarre question because the Maine Coon is an entirely domestic cat by which I mean NOT a wild cat hybrid and therefore there is no reason whatsoever to declare it illegal in any jurisdiction unless that there is some other fanciful reason to ban the cat (there might be - see below). Are Maine Coons illegal in some countries, states or territories? No, to the best of my knowledge. Image: MikeB I know of no jurisdiction anywhere in the world that bans Maine Coons which makes sense. Conversely a similar sized domestic cat, the F1-F2 Savannah, is illegal in many jurisdictions (states, territories and countries) because it is a wildcat hybrid. The cat has some wild cat DNA which some legislatures consider to be detrimental to human health and welfare and to the conservation of wildlife (if the cat escapes t...
Read more

Tortoiseshell Maine Coon with split-face

-
Image
Maine Coon with "split face". Photo: Screenshot. This is a very impressive Maine Coon. As you can see she is a tortoiseshell and as you probably know almost all tortoiseshell and calico cats are female. There are a few male tortoiseshell cats (and this might be one of them). Their sex is caused by a genetic aberration because the genetics of tortoiseshell cats dictates that they are almost always female. About one in 3000 are male as I recall. Also, it is not that unusual to see this extreme pattern on the face which creates the appearance of a "split-face". This is not what is called a "chimera" but a normal variation of the tortoiseshell pattern. Sometimes you do see what some people call "two-faced" cats with this sort of face due to a sharply defined pattern down the middle of the face. But the genetics behind that is different to this normal tortoiseshell variation. This is a particularly extraordinary looking Maine Coon cat. Not all Maine C...
Read more

5 Maine Coon transformations from kitten to adult (video)

-
Image
Maine Coon kitten and his adult self. Photo: Robert Silka. This is a series of photographs by the very famous Maine Coon photographer: robert_sijka. I think he presents his photographs too dark as there is not enough information in the photographs for my liking but he takes great photographs of great Maine Coon cats. In this series he photographs a kitten and their adult version. Each individual cat is a wonderful example of the Maine Coon breed. I can count five examples. In my experience, these Google Blogger videos only work if you click the centre play button and then, immediately afterwards, the play button bottom-left! It sounds bad but the short video is worth watching.
Read more

Eerie picture of a Maine Coon sitting like a human on a chest of drawers

-
Image
This is a slightly scary picture according to those who've seen it. One social media user said it was the devil and "If I walked into a room and saw that, I would assume some shit is about to go down". There is a ghostly stillness and sinister feeling about the image. 'Eerie' is a better description. This attractive cat appears to be completely at ease and comfortable sitting on top of a chest of bedroom drawers. The lighting from below (deliberate?) enhances the eerie effect. It seems possible that this is a photo-edited image but if so, it has been done with great skill. However, I don't think this is Photoshopped. Rethink: to be honest, the more I look at the picture, the more I feel that this is a photo-edited image. It is just too unnatural to be real. Although some domestic cats get themselves into some very strange positions. Maine Coon calmly sitting just like a human on a chest of drawers. Picture source unclear. Image deemed to be in the public d...
Read more

Picture showing a Maine Coon as big as a child

-
Image
Another good example of the size of the bigger Maine Coons. Photo: Reddit.com This is a good photograph from the point of view of comparing size because it is from above and so we can see the full length of this almost totally black Maine Coon with white boots. The cat looks bigger than the child which is possible because I've seen Maine Coons which are positively enormous. I'm sure breeders of this cat go out of the way and bend over backwards to breed the biggest Maine Coon that they can. It's a challenge. They're not meant to necessarily be as big as this, as far as I know. That wasn't the initial objective under the breed standard. The standard does not say that Maine Coons must be enormous. In fact, the Cat Fanciers' Association breed standard, in the opening paragraph provides an overview of the cat and there is no mention that this cat should be very big. It is reproduced below (great cat though): "GENERAL: originally a working cat, the Maine Coon is...
Read more

Should Maine Coons wear collars?

-
Image
Should Maine Coon cats wear collars? It's a question posed by the owner of the website Maine Coon Central and I think the question is not a great one to be perfectly frank but it does just about need to be addressed which is why I am writing this article. Maine Coon cat wearing a collar. Photo by Warren Photographic (modified by MikeB) and used with his express permission. You could ask the same question about any domestic cat that goes outside. Cat collars normally contain an identification tag. Cats that go outside might get lost. The ID tag can help them be reunited with their owner without recourse to having to scan for a microchip. The thing is though that it is probably exceptional for a Maine Coon cat to be allowed to go outside unsupervised. Quite rarely people take them outside on a harness and lead to allow them to explore the outside and be mentally stimulated. However, under these circumstances you don't need a collar with an ID tag for obvious reasons (unless they ...
Read more