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Standard and health? A provocative question?
Let us read the standards regarding the aspects of their
proportions and implications for health.
Standard Manx in
TICA,
Manx Breed Group Standard, 05/01/2004:
BODY:
Torso: short back which forms a smooth continuous arch from
the shoulders to the round rump.
Body should not be so short that it appears out of balance.
Legs: Sturdy boning and well-muscled. Forelegs shorter than
hind legs. Hind legs with substantial musculature, should be
straight when viewed from behind.
GENERAL DESCRIPTION:
The Manx and Cymric have short front legs, height of hindquarters,
great depth of flank, and a short back which forms a smooth
continuous arch from the shoulders to the round rump.PENALIZE:
level back; short hind legs, fine boning, bowed or cow-hocked
(knock-kneed) hind legs. |
The back shall be short.
A very dangerous wording, when thinking on the possible
problems, which Manx may have.
We will make a short excursion into the anatomy of the spine.
 |
| atlas |
1st vertebra of the neck carrying
the head |
| axis |
2nd vertebra of the neck, it is the
axis for the 1st vertebrae to turn the head around |
| orbit |
hollow for the eyes |
| mandible |
lower jaw |
| hyoid |
bone for the tongue |
| The spine is divided
into different regionst: |
| vertebra |
the single bone forming the spine |
| cervical vertebrae |
7 vertebrae for the neck |
| thoracic vertebrae |
13 vertebrae at the location of the
chest
humans have 12; the ribs are mounted in this region |
| lumbar vertebrae |
7 vertebrae
humans have 5 |
| sacral vertebrae |
3 vertebrae
humans have 5 |
| coccygeal vertebrae, the first part
of the caudal vertebrae |
humans have 3-5 vertebrae, which are
melted together (Coccyx) |
| scapula |
shoulder blade |
| clavicle |
bones at the shoulder, where the
arms are mounted, in cats the clavicles are "floating" and freely
moveable, when compared with humans, which allows cats to slip
through every opening, when the head can slip through |
| humerus |
upper bone of the arms
remark: the term "arms" is usual in animals |
| radius |
at the side of the large toe at the
front legs (inside) |
| ulna |
at the side of the small toe at the
front legs (outside) |
| carpals |
bones at the root of the palm (feet) |
| metacarpals |
middle bones of the palm (feet) |
| phalanges |
bones of the toes |
| sternum |
bone in the middle of the chest
The wording that the cat has a sternum to indicate a fault in
xiphoid is wrong, because each cat has a sternum. |
| xiphoid process = xiphoid |
the process at the end of the
sternum |
| The ribs are divided
into: |
| costa |
rib |
| costae verae |
true ribs mounted to the sternum via
cartilage |
| costae spuriae |
false ribs, those are melted
together and are mounted to the sternum via a bony arch |
| costa fluitans |
floating rib, freely moveable, it is
not connected with the sternum |
| femur |
upper bone of the hind legs |
| patella |
|
| tibia |
one of the two long bones of the
lower hind legs |
| fibula |
the second of the two long bones of
the lower hind legs |
| tarsals |
bones at the root of the feet |
| metatarsals |
bones of the middle of a foot |
We are interested in the spine of the Manx. There had been done
researches, how the vertebrae and the regions of the spine are
developed in the Manx, when compared to cats with normal length of
tail.
There are 4 types of Manx:
| |
|
number of lumbar
vertebrae |
number of coccygeal
vertebrae |
| Rumpy |
completely without any
tail,
they also do not have any coccygeal vertebrae |
6,7 |
0 |
| Rumpy Riser |
they also do not have
any tail,
but they have coccygeal vertebrae with less vertebrae than
normally tailed cats |
6,9 |
4,4 |
| Stumpy |
they have a very short
tail,
they also have less coccygeal vertebrae and much less caudal
vertebrae |
7,0 |
10,3 |
| Longie |
with normal length of
tail, normal amount of coccygeal vertebrae |
6,9 |
19,6 |
| Domestic
cats |
|
7,0 |
21,9 |
Concerning the cervical and thoracic vertebrae there were no
significant differences in the number of vertebrae.
But the length of vertebrae was different between the different types
of tail:
There were also found sex-related differences in the length of
vertebrae.
 | Males have significantly shorter cervical vertebrae, Stumpy had
the shortest length of vertebrae. |
| Rumpy-females have significantly shorter thoracic vertebrae. |
| But also Longie had shorter thoracic vertebrae then Domestic
cats. |
| In both sexes the lumbar vertebrae were significantly shorter
than in Domestic cats. |
| The largest difference in length could be found in the coccygeal
vertebrae, where Stumpy had the shortest coccygeal vertebrae. |
Literature:
| Morphological Effects of the Manx Factor in Cats |
Joyce M. Howell, P.B: Siegel, Journal of Heredity, 1966; 57; 100-104 |
| Expressivity of the Manx Gene in Cats |
Roy Robinson, Journal of Heredity, 1993; 874; 170-172 |
The more significantly shorter the vertebrae and consequently the
shorter the regions of the spine are, the more severe the deformities
are, and also the mortality rate is significantly higher.
THEREFORE:
It is a bad wording and phrasing concerning the health, and a bad
service and support is made for the Manx, if the standard requires a
short, arched back.
Let us look at other organizations, what they write in the standard
concerning the back:
|
CFA |
GENERAL:
short back which arches from shoulders to a round rump
BODY:
The short back forms a smooth, continuous arch from shoulders to
rump, curving at the rump to form the desirable round look. Length
of back is in proportion to the entire cat
LEGS and FEET:
forelegs short, Hind legs much longer than forelegs
|
| FIFe |
General:
the short back and the depth of the flanks are the characteristics
of the ManxBody:
back compact and short but in balance to the body,
ending in a definite broad and round rump
Scale of Points
Back: shortness 10 points
Legs:
front legs short
the hind legs are higher than the front legs forming an angle
from the back to the front of the body |
|
WCF |
Body:
The back is very short, ending in a rump ideally as round
as an orange.Scale of Points
Back length 10 points
Short front legs, hind
legs are higher than the front legs |
As one can see here, all standards emphasize, that the back shall be
short. There are even 10 points awarded for the shortness of the back.
| When reading the literature carefully, where one can already see
very clearly, that the vertebrae are shorter and consequently the
regions of the spine are shorter, especially in the posterior two
regions, such standards will be the cause that the vertebrae will
become even shorter, because breeders will breed for a shorter
back. |
| It would be much better to require a cobby body, which
already includes some shortness implicitly, and to drop such
wordings like "short back", and to redistribute the 10 points to the
balance of the body. |
The front legs shall be short.
Also such a wording is quite dangerous, as the above mentioned
organizations require also sturdy legs.
Shall it be desirable that Manx cats will hop instead to run?
| It would be already sufficient enough, when it is written that
the hind legs are significantly stronger and longer.
The logic conclusion that the front legs are
shorter can be drawn, but the option is left open to have also front legs of
medium length, which probably would be much better for the spine. |
| It would be also sufficient, when it is written that the legs
shall have strong bones. |
TICA is the only organization, which requires straight hind legs and
considers angulated hind legs, as required in FIFe, as a fault, which
is for sure an advantage for the patella.
| To require angulated hind legs will shift the weight of the rump
to the knees, and that will harm the patella! |
Conclusions
All organizations emphasize the layout of the Manx, that it looks
cute with its short back.
A short back will increase the problem, that the vertebrae and
the posterior regions of the spine are already shorter than in
domestic cats, and will support to breed for even shorter vertebrae
and a shorter spine, and thus the problems, which can be found in
Manx, will be even enlarged.
Angulated hind legs together with an arched back shifts the
weight to the knees and will put more weight on the patella.
To be continued: The Manx syndrome. © katzenzeitung 4/2008 |
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