So we’ve talked about Scottish folds and Persians (and other brachy breeds), but I haven’t seen a lot of talk about manx cats.
oh my gosh, isn’t she cute? :D Just look at that little tuft of fur on her butt! She doesn’t have a tail! Who else wants to go out and get like a million little bunny cats?
Stop. It’s time to talk about Manx Syndrome. The name itself is a bit of a misnomer, since it doesn’t just affect manx cats (or even EVERY manx kitty; Nala exhibited only very mild symptoms). Cymrics are also affected. For simplicity’s sake, it’s often just called Manx Syndrome. What it IS, is a form of spina bifida.
Tail development is highly linked to spine and spinal cord development. When a cat is bred to lack a tail, they’re being bred for abnormal development of coccygeal (tail) and sacral vertebrae (the spinal cord just in front of the tail). It can also affect vertebrae further up the spine in particularly severe cases.
This can cause some pretty serious issues including urinary incontinence, chronic diarrhea, constipation, and their hind limbs may not function properly. We also see megacolon or rectal prolapse in these cats—- the fact that they lack the tail muscle also means they lack certain colon muscles, resulting in a failure to push poop out. The more serious symptoms are generally present by the time a kitten is 6 months old. They’re usually euthanized at that stage. If they aren’t, they will usually end up wearing diapers their whole lives (or require manual manipulation to poop, if they’re constantly constipated; this is, needless to say, extremely unpleasant for everyone involved) and require very frequent bathing.
In manx cats, there are varying tail lengths:
Rumpy riser - either just a few vertebrae, or even just cartilage
Stumpy - a few centimeters of tail
Stubby - a tail that’s about half the length of a typical cat’s tail
As you get shorter and shorter, the likelihood of spina bifida increases. I still see cats with tails affected by manx syndrome. A study done in 1979 (warning: study includes pictures of internal organs and dissections) produced nine rumpy cats, three rumpy risers, fourteen stumpies and eighteen longy Manxes. All of the rumpies had MS, two of the rumpy risers did, and only one of the stumpies had it. The longies were almost unaffected— they still presented with more arthritis in their tail than typical cats, though. So having just a few vertebrae protected these cats from the worst effects of MS.
Taillessness is caused by the M gene. It’s an autosomal dominant gene, so a cat needs only one to present with tail-abnormalities; this means a cat with Mm will not have a tail, while a cat with mm will HAVE a tail. A cat who develops with MM dies in utero. They simply don’t develop. Honestly, the fact that it’s a lethal combo is pretty telling, so let’s get into detail EXACTLY WHY IT’S LETHAL.
And this is because the M gene punches holes in some pretty important codes. So think of a vertebrae like a pizza pocket: you got the bone on the outside, then there’s a membrane (meninges), and finally there’s bundles of nerves on the inside. But the M gene can cause holes in the bone, exposing the meninges. The meninges can be squeezed through the holes (called “Meningoceles”), which puts a lot of pressure on the nerves inside. You know, kinda like when you squeeze a stress toy.
So a cat with MM would develop with LOTS of these holes, exposing the meninges, while a cat with Mm only develops SOME holes exposing the meninges. That’s… that’s still pretty bad. The ideal number of holes is zero. Now, these meningoceles CAN naturally heal over time, but the cats often still exhibit urinary incontinence and other issues associated with Manx Syndrome (see the 1979 study linked above).
“Ok, but could we just… breed Manx cats to have longer tails?”
Unfortunately, we can’t. The M gene is highly penetrating and inconsistent. Even if it’s not causing a visible abnormality (ie, lack of tail), it’s still frequently present. This means that even a long-tailed manx still presents issues such as tail kinks. Stumpy cats also tend to develop arthritis at a higher rate than typical cats— you can even feel it in their tails sometimes. They’re so stiff, it’s like grasping a stick. Vets may even opt for amputation to reduce the pain. Considering phantom limb syndrome, even this may not help.
Now, the good news is that there are short-tailed cats WITHOUT Manx Syndrome. The Japanese and American bobtail breeds both get their little cute tails from a completely separate mutation and, as far as I can tell, it’s harmless. I’m not certain about the Kurilian bobtail.
If you have your heart set on a manx kitty, please, PLEASE go to a rescue and be aware of what to ask. Be sure to ask if the cat has any symptoms and be prepared to handle them if they develop later in life. Even if your breeder-produced kitten turns out just fine, there could be many more that didn’t make it. One healthy kitten isn’t worth the price of suffering. Breeding should be done to improve a breed, including their health, not merely to stick to the standard perfectly. If the breed includes an inherent amount of suffering, it should not be reproduced further.
2087
germansingergirl
gracieabrams
prguitarman
theartofmadeline
