Cardigan Welsh Corgwn
Some of the more difficult problems facing breeders of Cardigans and many other achondroplastic or "dwarf" breeds of dog are undesirable anomolies or distortions of the bones and joints. Breeding to prevent and improve structure is one of the key concerns of a good breeder and understanding how certain traits are inherited is a very important part of this goal.
Structural problems related to dwarfism are sometimes minor and might be little more than an undesirable feature like incorrect head proportions or leg length, but in other cases they can lead to CHD (Canine Hip Dysplasia), IVDD (Intervertebral or Degenerative Disk Disease in the back), OCD (Osteo Condritis Dessicans, a problem affecting the elbow joint), Luxating or Sub-Luxating Patellas ('popping' kneecaps), hyper-extending (weak or double-jointed/popping) Hocks, Degenerative Joint Diseases (DJD) like Osteoarthritis and problems affecting the ligaments leading to slow development in puppies ('swimmer' puppies or puppies that are abnormally slow to walk after 3-4 weeks of age). There seems to be one more or less common form of dwarfism in the breed described as hypochondroplasia, but there might additionally be several more co-existing forms including achondroplasia and pseudochondroplasia in the cardigan gene pool which can result in much smaller than expected individuals or individuals having the more extreme features of dwarfism with the above listed problems and/or a higher puppy/neonatal mortality rate. To read more about the many different forms of dwarfism, the Little People of America Medical Resource Center offers an informative list of identified types of dwarfism and related conditions affecting humans .
In the interest of understanding the nature of dwarfism in cardigans and working towards improving the Wyntr line, radiographs of hips, elbows and patellas have been taken and sent to the OFA for evaluation. The results have been as variable as the many other features of the breed. More recently, the OFA has begun to accept cardigan radiographs of the spine to it's registry. Celeste is the first of the Wyntr cardigans to be submitted for registration.
Below are links to see radiographs of most of the individuals in the Wyntr line, plus some of the 'old timers' who are less closely related. The only dogs missing at this time are Bolt and Bastion, who unfortunately did not have duplicate or 'discard' copies of their hip radiographs available and the only originals are currently filed with OFA. With the advent of digital imaging, this will hopefully no longer be a problem in the future.
Blast: Hips Elbows - left right Front
Quick: Hips Elbows - left right
QT: Hips Elbows - left right
Shade: Hips Elbows - left right
Rah Rah: Hips Elbows - left right
Avalanche: Hips Elbows - left right
Bastion: Elbows - left right
Beautiful: Hips (see notes below for more information on this radiograph) Elbows - left right
Beautiful's radiographs 2006 : Hips Spine: Lumbar
Quick & Beautiful's Kids
See the hip radiographs done on five of Beautiful's puppies at 11 weeks:
Clover | Clarion | Celeste | Cruiser | Colossus
Cowboy 2007 - Hips Elbows: Left Right Spine: Thoracic Lumbar
Celeste 2007 - Hips Elbows - left right Spine: Neck 1 Neck 2 Thoracic 1 Thoracic 2 Lumbar 1 Lumbar 2
Fudge: Hips (age 13) Spine: Lumbar (age 13)(see notes below)
Dare - front(see notes below for more information on this radiograph)
Tully: Hips Elbows - left side view, left top view, right side view, right top view, Patella/leg - left, side view (see notes below for more information on these radiographs)
See Beautiful just a few minutes before she was born!
see notes below for more information on these radiographs
When looking at the hip images, the view is looking down at the dog while it is lying on it's back, so the left leg is on the right side of the image and visa versa for the right leg.
For elbows, the view is looking down at the inside of the leg with the dog's shoulder/body located outside the image at the top.
Most of these radiographs are discarded images which were taken for OFA evaluation, so in many cases postioning may not be optimal, particularly Beautiful's first evaluation which has the right leg (on the left in the image) in the position required by OFA and the left leg (on the right) in what would be her normal leg extension. Note the curvature of the femur (upper leg bone) of the normally extended leg. This trait is common in dwarf breeds, especially those with heavier bone structure. A curved femur makes correct OFA evaluation very difficult in many cases when the leg has to be twisted in order to bring the bones into a postition where all the structures can be seen. In Beautiful's case, it would be almost impossible for her to turn her femurs this way under normal circumstances. and a repeat evaluation by OFA still describes her as "mildly subluxated". The scanned image sent to OFA is the one pictured in the above link under 'Beautiful's radiographs 2006'. There have been no significant changes since her first evaluation. The image of her spine was taken to check for any potential back problems. The image actually shows a better view of the contents of her colon than the structure of her spine. It is hard to see, but there is some very slight arthritis in her mid-back which was not considered a great concern at this time, but would still bear watching to ensure that nothing worse develops.
The radiographs of Beautiful's puppies were done without anesthesia, so several images have poor positioning due to the wriggly nature of puppies. This is particularly noticeable in Celeste's hip image where she attempted to turn herself over as the image was taken, so her spine, pelvis and right leg appear twisted while her left hip is blurred. Clarion's femurs are forshortened in appearance due to his legs being raised rather than extended when the image was taken and this may also be the case with Colossus. The immaturity of development can be seen in the incomplete growth plates on the inside center portion of the hip sockets in all the puppies and the overall softer, less calcified appearance to the bones.
For Blast and Dare's fronts, the small circle that can be seen just above the sternum in the image of Blast's front is the location of his trachea which has been intubated for gas anesthesia. The trachea is less obvious in the image of Dare's front because injectable anesthesia was used instead. Dare had what is known as a 'barrel' or a round chest shape with a 'flat' sternum and 'out elbows' giving a very bowlegged shape to his front. This is most obvious when compared to Blast's front. Blast has a correct oval shaped chest and although his forarms are bent in the manner described in the standard, his elbows do not bow outward from his body in the unsound manner seen in Dare's front. There is a mistaken belief among many breeders that a puppy with the sort of front like Dare's will improve or correct itself with maturity. What is often happening is that muscle and ligament development will build up to stabilize the forelegs and sternum, making the elbows appear to 'come in' and the chest to 'drop', but this does not change the actual weak underlying structures.
On Tully's radiographs, he developed a problem known as OCD in his left elbow at around 7 months old due to premature closure of the growth plates in the ulna of that leg. As a result, his elbow joint became slightly deformed, fracturing the cartilage and eventually resulting in osteoarthritis and degeneration in the joint. Unfortunately the x-ray machine used was an old one, so it is not the best image, but the difference can be seen when compared to other more normal cardi elbows like Blast's. Tully also suffered from a more generalized osteoarthritis for most of his life, a problem often associated with some forms of human dwarfism. Some osteoarthitic changes can be seen as a cloudy or blurred appearance to Tully's right hip joint. He also had a mildly luxating left patella. The image of his left leg shows the patella in it's proper postion (a small slightly diamond shaped bone in the upper right part of the image), but the inside part of the groove in which it rests is noticeably more shallow than the outside, which results in the kneecap 'popping' out of joint occasionally.
On Fudge's radiographs, she was showing some signs of rear limb weakness and loss of coordination. There was concern it might have been IVDD (intervertebral disk disease), but further analysis determined her problem to be DM (Degenerative Myelopathy). Unfortunately this progressive disease was untreatable at the time and I lost Fudge a year later to complications of this disorder. Sadly, so far stem cell research has not provided a treatment option as hoped and only regular low impact exercise has helped in delaying onset of symptoms in at risk or affected individuals. On a more positive note, a DNA test has been developed and Cardigan breeders how have this as a means to screen and make breeding decisions more reliably in order to reduce the incidence of this devastating disorder.
E-mail your comments or questions about these radiographs.
HOME | ARTICLES | Wales Trip | Kathy's Icons | NEW Wyntr Website