Part Two of our guide to French Bulldog health and genetic conditions deals with French Bulldog spine malformations and disease, hip and patellar issues, hot spots and skin problems.
The French Bulldog’s Spinal System
The French Bulldog was selectively bred from dwarf examples of the English Bulldog. This fact, when combined with the intentional selection of shorter specimens in the breeding programs of today and yesterday have combined to give us both today’s short backed dog, and the plethora of spinal issues plaguing this breed. Another possible correlation is the breed standard’s prized ‘short and lowset’ tail, which sometimes manifests as a non existent, telescoped or screw tail.
Hemivertebrae is a defect present at birth and genetically based, although the genetic structure appears to be a complex (multiple genes involved) interaction. Commonly referred to as “butterfly” vertebrae, hemivertebrae has its highest incidence in brachycephalic (short muzzled), screw-tailed dog breeds. In fact the screw-tail is actually an example of a hemivertebrae formation. This malformation may be pleasing when located in the tail but can have serious repercussions when located elsewhere in the spine.
Hemivertebrae are the result of the left and right halves of a vertebrae failing to fully fuse during fetal development. The resulting vertebrae resembles a butterfly when viewed from above. Each half of the hemivertebral body often grow unequally, creating a wedge-shaped (viewed vertically) body. The presence of a wedge vertebrae can cause a dorsal curvature (kyphosis) or a lateral curvature (scoliosis). Deformations in the backbone can compress the spinal cord and/or its blood supply, with serious ramifications.
Symptoms indicative of hemivertebrae will be dependent upon the number of malformed discs and the locations of these discs. The best way to be assured of proper spinal formation is through x-ray evaluation by a veterinarian familiar with “proper” spinal formation for your breed. My vet and the orthopedic vets at Guelph University feel that detection of Hemis may be successfully done as early as four months.
von Willebrand’s Disease
von Willebrand’s disease is a bleeding disorder found in many breeds of dog as well as other animals. It is characterized by hematomas, nosebleeds, and intermittent limping (due to bleeding into the joints). Similarly to hemophilia A, dogs with this disorder are deficient in clotting factor VIII activity. One of the primary distinctions of von Willebrand’s disease however, is that this disorder is not sex-linked.
Hereditary von Willebrand’s disease is complex. Each breed of dog will have a different set of “typical symptoms” of the disease. Symptoms can range from abnormally long bleeding time due to a cut toenail, to hemorrhaging during minor surgery, to spontaneous nosebleeds, with a wide assortment of presentations between. Injuries that are followed by bleeding may or may not require a transfusion. Even a small wound may necessitate veterinary treatment. Carriers of this disorder can live their entire lives with no outward indications of this disease.
Only through testing of all prospective breeding stock and selective breeding is there a hope of eradicating this disorder. The test is simple and inexpensive, and will show if the tested dog is a high, low or non carrier of the disease. The common sense procedure of not breeding from high carriers, and of not breeding low carriers to other low carries may eradicate vWD forever from our breed.
Hip Dysplasia (also called CHD – Canine Hip Dysplasia
Hip dysplasia is the most common cause of rear-end lameness in canines, and is due to the structure of the hip joint. In the healthy dog there is a broad pelvis with a rounded cup into which the ball of the femur fits solidly. The ligaments and good musculature hold the ball in place while allowing free motion of the femur. Canine hip dysplasia (HD) is caused when the femoral head does not fit properly in the hip socket, causing instability of the joint. Over time, this malformation can cause degenerative joint disease (DJD) which causes increased pain and immobility. Surgery can help to correct the problem, but can be expensive and stressful for dog and family. Genetics play the largest role in whether or not a dog will develop hip dysplasia. Other factors include environmental (including weight and nutrition) and under what conditions the puppy is raised, also training methods and rearing practices. Even dogs with normal hips can produce dysplastic puppies.
Breeders can (and should!) have their breeding stock x-rayed by their vets, with the x-rays sent to either the OFA (The Orthopedic Foundation for Animals), the GDC (Institute for Genetic Disease Control), or, in Canada, the OVC (Ontario Veterinary College). All three of these bodies maintain open registries on hip health in tested dogs.
Patellar Luxation
Patellar luxation is the dislocation (slipping) of the patella (kneecap). In dogs, the patella is a small bone that shields the front of the stifle joint. This bone is held in place by ligaments. As the knee joint is moved, the patella slides in a grove in the femur. The kneecap may dislocate toward the inside (medial) or outside (lateral) of the leg. This condition may be the result of injury or congenital deformities (present at birth). Patellar luxation can affect either or both legs. Testing is available to predict a the presence of PL in a dog, but cannot predict it.
The most common occurrence of luxating patella in French Bulldogs is the medial presentation. Shallow femoral groove, weak ligaments and malalignment of the tendons and muscles that straighten the joint are all conditions that will predispose a dog toward luxating patellas.
Indications of patellar luxation are; difficulty in straightening the knee, pain in the stifle, limping, or the tip of the hock points outward while the toes point inward. The diagnosis of this condition can usually be confirmed (by a veterinarian) by manipulating the stifle joint and pushing the patella in and out of position.
There are 4 grades of deviation for this condition:
Grade 1:
Intermittent patellar luxation – occasional carrying of the affected limb. The patella can easily be manually luxated at full extension of the stifle, but returns to proper position when pressure is released.
Grade 2:
Frequent patellar luxation – in some cases luxation is more or less permanent. The affected limb is sometimes carried, although the dog may walk with the stifle slightly flexed.
Grade 3:
Permanent patellar luxation – even though the patella is luxated; many animals will walk with the limb in a semi-flexed position.
Grade 4:
Permanent patellar luxation – the affected limb is either carried or the animal walks in a crouched position, with the limb partially flexed.
Medial is termed “congenital” because the luxations occur early in life and are not trauma associated.
Clinical indications:
1) Neonates and older puppies – display clinical signs of abnormal leg carriage and function from the time they start walking. These cases are generally grades 3 or 4.
2) Young to mature animals – usually exhibit intermittently abnormal or abnormal movement all their lives. Generally evaluated when the symptomatic gait worsens. Most often grade 2 or 3.
3) Older animals – may exhibit sudden lameness. Usually due to further breakdown of soft tissues or the degenerative nature of joint disease. These cases are usually grade 1 or 2.
There is a school of thought that French Bulldogs frequently have Grade 1 luxations. One of the most common French Bulldog poses, the rear leg extended sit which gives them their typical ‘frog look’, is actually considered to be an indicator of luxation. Breeding from an animal exhibiting any form of diagnosed luxation is doubtful, but breeding of any dog with a level 3 or greater luxation is decidedly inadvisable. OFA, GDC and OVC all do screening for patellar luxation.
Hot Spots
A “Hot Spot” is an area of bacterial skin infection that increases through self-mutilation by the dog. An area of skin is irritated (flea bite, allergy or other irritant), the dog scratches or chews the area enlarging the opening, the area becomes infected, thus begins the cycle. Hot spots are warm, swollen, painful patches of skin that exude pus and serum, and tend to give off a foul odor. These areas can appear suddenly, they tend to enlarge rapidly (especially in hot humid weather) and can reach a size of several inches in diameter. Hair loss is rapid. Between the dog chewing or clawing the coat out and bacterial spread the progress can be significant within a matter of hours. Hot spots most often appear on the neck, ears, chest, rump, flanks, and back (areas of access to clawing or chewing).
Treat by clipping all remaining hair away from the infected area. This will allow air to dry the area and promote healing. Gently cleanse the area with a surgical soap (pHisoHex, Oxydex, or Betadine). Apply topical antibiotic-steroid cream such as Panalog to aid in reducing irritation and promote healing. Dependent upon the extent of the hot spot the dog may need oral antibiotics and steroids as well. The dog must be restrained from doing further damage to this area, this may necessitate the use of an Elizabethan collar.
To end the cycle the underlying cause must be determined. In the event of fleas – the fleas must be removed. In the event of allergies the irritant must be determined and eliminated to prevent hot spots from occurring elsewhere. A word of warning – do NOT treat hot spots with tea tree oil! Tea Tree oil has been known to cause neurological damage in canines and humans when applied in the undiluted form.
Atopic Dermatitis
Atopic dermatitis is known by many names throughout the dog world. Among these names are: canine atopic dermatitis, canine inhalant dermatitis, allergic inhalant dermatitis, atopic disease, and inhalant allergy. This condition is a commonly occurring, inherited, hypersensitivity to pollens or other environmental allergens, as a result of a disorder of the immune system.
The primary clinical indication is itching. This itching can take one or multiple forms, and is most often exhibited by licking or chewing of the feet, and/or the groin area; rubbing and scratching the face, ears, and front torso; rubbing sides or buttocks on furniture or any available object; and frequent periods of “sit and spin” sessions. Additionally, affected dogs can display reversed sneezing, coat discoloration, crusty, reddened eyes, reddening of the skin, papules, and hair loss.
This condition can vary greatly from region to region. Since the most common allergies are: dander, pollens of grasses, weeds, and trees; dust and molds. The irritants can be seasonal and some regions of the United States have a higher incidence of irritants than others. Found in both males and females, this condition has a higher incidence in females. The most common age of onset is between one and three years of age. It is alarmingly common in French Bulldogs, and its origins are a mystery at this time. It has been theorized that hypothyroidism is at root of this disorder, but thyroid testing of the dogs which we have had with this condition have been negative. Perhaps there is some other, underlying immune suppression at work which are not yet equipped to pin point or diagnose.
Idealistically, avoidance of the irritating substance would present the most desirable long-term means of treatment. This can be achieved in some cases, but in most this is not a practical solution. Medically, there are numerous treatments such as glucocorticoids and/or antihistamines. In some cases hypo-sensitization is the best means of treatment.