|Canine Hip Dysplasia
This disorder also has a hereditary basis, but the patterns of heredity are more difficult to predict than with the eye disorders. Parents certified free of hip Dysplasia may produce some puppies with this condition. Dogs with the condition should never be bred. Diagnosis can only be made by X-ray examinations. Environmental factors such as nutrition of young puppies and rearing practices can cause or increase the severity of the condition. Talk with your veterinarian for more detailed information.
Canine Hip Dysplasia is observed in all breeds with an adult weight greater than 35 pounds. The problem is in the development of the boney structures of the hip joint. In normal hip joints the femur (thigh bone) sits solidly in the acetabulum (cup of the pelvic bones). In hip dysplasia, loose ligaments allow the head of the femur to begin to work free as the puppy grows. Because of this joint laxity, there is abnormal wear and tear on the boney surfaces that touch resulting in the development of arthritis. This arthritis results in varying degrees of symptoms including pain and restricted movement.
The Orthopedic Foundation for Animals (OFA) will certify the X-rays of breeding dogs as normal and issue a certification number. The dog must be at least 2 years old to obtain an OFA certification. Ask to see these documents on both parents before purchasing a puppy.
Further reading: Hip Dysplasia (CHD) by Jack Vanderwyk
Retinal dysplasia involves
abnormal development of several structures of the visual system. Dogs may
be very mildly affected and demonstrate folds in the retina. These are
areas where extra retina develops and instead of forming a thin membrane
over the back surface of the eye, the extra retina develops into folds.
This fold results in a blind spot. Often times the retina is also undernourished
and an area of retinal degeneration will occur. Dogs with mild changes
(i.e. a few retinal folds), usually have no
Labradors with a more severe form of retinal dysplasia may result in blindness due to large areas of retinal folds or degeneration. Retinal detachment can also develop resulting in blindness. The more severe form of retinal dysplasia can occur with retinal separation, cataracts, and eye enlargement in dogs which inherit the gene from both the bitch and stud dogs. These dogs also may suffer from skeletal dysplasia or dwarfism, as the same gene for retinal dysplasia (which works in a dominant fashion for the eyes) cause skeletal dysplasia (in a recessive fashion).
Further reading: Dwarfism by Jack Vanderwyk
Source: Dog Owners
Home Veterinary Handbook, Delbert Carlson, DVM and James Giffin, MD
PROGRESSIVE RETINAL ATROPHY
HEMOPHILIA A, FACTOR VIII OR AHF DEFICIENCY
DWARFISM ASSOCIATED WITH RETINAL DYSPLASIA
DEFICIENCY OF TYPE II MUSCLE FIBERS
EXERCISE INDUCED COLLAPSE
CONGENITAL PHIMOSIS AND CUTANEOUS MAST CELL TUMORS
VITAMIN A RESPONSIVE DERMATITIS
PERSISTENT HYALOID ARTERY
PERSISTENT PUPILLARY MEMBRANE
FACTOR IX DEFICIENCY
UNUNITED ANCONEAL PROCESS