Australian Shepherd Health & Genetics Institute

Australian Shepherd Health & Genetics Institute

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Bones & Joints FAQs


What is Elbow Dysplasia (ED)?

ED is not a single disease, but rather a set of related defects that are grouped under the term “elbow dysplasia.”  If your dog is diagnosed with ED, it may have fragmented medial coronoid process (FCP),  ununited aconceal process (UAP), or osteochondritis desicans (OCD).   Some dogs diagnosed with incomplete ossification of the humeral condyle are deemed to have elbow dysplasia.  The condition arises in the cartilaginous growth plate at the elbow end of the humerus, the bone above the elbow joint when the growth plate fails to harden as it matures.  This particular problem seems to be restricted to Spaniel breeds and is probably not be a concern for Aussie breeders.  Either or both elbows may be affected.  Larger boned and faster growing pups seem more prone to this disease than dog with moderate or light bone or who mature more slowly.  Having elbow dysplasia is a risk factor for also having hip dysplasia; the more serious the condition the higher the risk.

How do I know if my dog has ED?

OCD, FCP and UAP all cause stiffness, stilted gait or lameness, usually while the dog is under a year of age and sometimes as young as 4 months.  The affected joint will be swollen and painful.  There may be atrophy of nearby muscles.  Some dogs are subclinical.  The only sure way to diagnose ED is with x-rays.  If x-rays still fail to reveal a cause for lameness, magnetic resonance imaging (MRI) or arthroscopy may be necessary.

OFA uses a single flexed view.  European registries use two views, one flexed and one extended, ) because they hold some cases may be missed if only a single view is used.

What does having ED mean for my dog?

In symptomatic dogs the joint will degenerate, resulting in diminished range of motion and chronic pain. Early surgical treatment accompanied by weight reduction and restriction of activity is recommended.  Some type of medication may be necessary.

How common is ED in Aussies?

It is also more common than most people are aware.  4% of the dogs in ASHGI’s 2009-10 health survey were affected.  ED has been largely disregarded in the breed, even though it is may be as frequent as hip dysplasia.  The Canine Health Information Center lists it as one of the mandatory screening procedures for our breed. 

Is ED inherited in Aussies?

Yes.  The inheritance of elbow dysplasia is complex and no specific genes have yet been indicated.  It is possible that some or all of the ED defects may be inherited independently though the frequency of the FCP/OCD connection indicates some relationship between them at least in a significant number of cases.  OCD is also felt to be the same disease no matter what joint it occurs in, therefore breeders should keep shoulder OCD cases in mind in relation to ED until science gives us better genetic information than is available at present.

The defects are most common in large, heavy-boned or fast-growing breeds, so it is possible that the disease may be to some degree secondary to body morph (which is itself inherited) but not all large, heavy-boned or fast-growing dogs get ED.

What does ED mean for my breeding program?

All Aussies intended for breeding should have their elbows screened.  Affected dogs should not be bred.  Parents and full and half siblings of an affected dog should not be bred close on the pedigree that produced ED or to mates with a family history of ED.

Another thing to consider is conformation.  Dogs that are fast-growing, large or heavy-boned for an Aussie may be  more prone to OCD in the elbow or shoulder.  If your dogs have these traits you will want to select away from them.

What is Hip Dysplasia (HD)? 

HD is a degenerative disease of the hips that arises from a combination of joint conformation and laxity.

Do “tight hips” mean my dog is more likely to have HD?

No.  When hip joints are referred to as “tight” it means the fitting between the femur (thigh bone) and the hip socket is firm.  The various hip registries recognize that tighter is better because tight hips are less likely to move around in the joint, causing wear and degenerative joint disease.  The PennHip system focuses specifically on the degree of laxity in the joint. The tightest, best-formed hips get the highest ratings or scores.

How do I tell if my dog has HD?

Radiologic exams (x-rays) of the hips are the only way to positively diagnose HD.  Affected dogs may or may not be lame or have poor rear locomotion.  Lameness and movement faults can be due to a number of other causes.

How do you know if HD screening results are good or bad?

No matter the system, most scores are relatively easy to interpret:  lower numbers are better than high ones, A is better than E, and “excellent” is, well, excellent.  You can usually find detailed information on scoring on the websites of the hip registries, whether kennel club operated or independent.

The British Veterinary Association (BVA) scheme used in the UK and some former colonies, and the US-based PennHip probably have the most complex scoring systems.  Neither designates dogs as dysplastic or not, but rather determines a continuum of scores for each breed.  In both cases you would want a dog to be better than the breed’s median.  The median score can change over time if hips get generally better or worse.  Current information should be available with other information about the programs.    By selecting breeding dogs from those with better than median hips you reduce your risk of producing HD and over time can improve breed hip joint conformation.

Is PennHip a better system for screening brood bitches?

You should not have your bitch’s hips evaluated by any method if she is in or close to her heat, pregnant or lactating.  Changes in hormone levels at those times can make the hips more lax than normal and may affect results.  These are normal fluctuations for a female, but since your hip x-rays capture only a single moment in time you risk giving the reviewer the impression that your bitch’s hips are always as they appear in that particular x-ray.

Does an OFA rating of Fair mean my dog is slightly dysplastic?

No.  A “fair” rating is not dysplastic.  Fair rated dogs will get an OFA number; dysplastic dogs do not.  OFA has three passing ratings:  Excellent, good and fair.  There are three dysplastic ratings:  Mild, moderate and severe.  There is one “in-between” rating:  Borderline, meaning they aren’t sure and you should have the dog re-examined after a period of time.  Only the passing ratings, including Fair, get an OFA numbers.

However, different hip evaluation systems use different criteria.  It is not uncommon for an OFA Fair dog to be given a borderline or mildly dysplastic rating in Europe.  This isn’t necessarily a matter of who’s right or wrong, but different approaches to the same problem.  But if you are a North American breeder using OFA who plans to sell dogs to other parts of the world, particularly Europe, you may not want to offer Fair dogs or offspring of Fair rated dogs to overseas clients.

What does having HD mean for my dog?

Over time the dysplastic hips accumulate greater-than-average wear, leading to degenerative joint disease (DJD).  Some don’t show visible signs until old age but occasionally very young dogs can be badly affected.  DJD can be extremely painful.  There are surgical options for the worst cases but the techniques are expensive and not always successful.   If your dog has severe hip dysplasia, discuss treatment options with your vet and consider consulting a veterinary orthopedist.  Having hip dysplasia is a risk factor for also having elbow dysplasia; the more serious the condition the higher the risk.

How common is HD in Aussies?

The 2009-10 ASHGI health survey indicated that 10% of Aussies have HD.  That is about twice the frequency reported by OFA.  However, an unknown number of dysplastic dogs’ x-rays are never submitted to OFA.  The actual frequency most likely lies somewhere between the two.   Even if the frequency is only 5% it indicates a very serious breed health concern.

 Is HD inherited?

Yes.  The disease is genetically predisposed but environmental factors including levels and type of exercise, nutrition, and sexual sterilization have bearing on the development and progression of HD.  Inheritance is complex.

 Is HD in one hip only inherited?

Unless there is overwhelming and vet-confirmed evidence of traumatic damage to the hip, yes.

Can I prevent HD by only breeding dogs that have really good hip screening results?

People put too much emphasis on hip screening results.  Screening is necessary, but even more important is family history.   If your dog has only the one affected near relative, this mitigates his risk but there is still a strong probability that he carries at least some genes for it and could produce it depending on what he was bred to.  You are more likely to get HD out of two OFA excellent rated dogs that have dysplastic siblings or offspring than out of two OFA fair rated dogs that have no affected kin.

 What does HD mean for my breeding program?

With genetically complex problems like HD, you have to look beyond the standard pedigree.  Determine the status of full and half siblings’ first-step relatives (parents, offspring, and full/half siblings) of your dog, its parents and grandparents.  Make a similar study of prospective mates.  If a dog has multiple affected kin a mate with few or none is needed, regardless of their specific screening results.  If you use the BVA or PennHip systems who will want to use better-than-median scores and the closer that score is to median, the correspondingly higher you would want the mate’s score to me.

A single case of hip dysplasia in an offspring is not grounds for removing a dog from breeding.  However, it should not be bred to the same mate again nor bred close on its own pedigree or that of the mate’s.  The same would apply to unaffected siblings.  Beyond that, follow the advice given above.

What is osteochondritis desicans (OCD)?

OCD is a loose bit of cartilage within a joint.  It can occur in  the elbow, shoulder or joints of the hind limb.  Dogs usually have shoulder or elbow OCD.  When it occurs in the elbow it is considered a form of elbow dysplasia.  The condition is painful and may require surgery.  It is possible for OCD to be caused by trauma, but not by the usual sort of bumps and bruises normal for an active dog.  The disease is frequently seen in larger, heavier-boned breeds (Rottweilers, Bernese Mountain Dogs) and dogs that mature rapidly.  Large, heavy-boned, or fast-maturing Aussies may be at increased risk for OCD.

How common is OCD in Aussies?

It is relatively rare, but when it is in the elbow it is considered a form of elbow dysplasia, which is common.

How do I know if my dog has OCD? 

Dogs with OCD will be lame in the affected limb but the lameness may be intermittent.  If your dog is lame, even occasionally, have your vet check it out.  All breeding Aussies should be screened for elbow dysplasia.  The screening process may reveal OCD in the elbow.

If your dog is affected, consult with your veterinarian about surgical options.  If the dog is active in performance events OCD may impact its ability to continue.

Is OCD inherited?

In almost all cases it is.  (Severe trauma to the joint can also cause it.)  Current veterinary thinking indicates that this disease may be part of a larger complex of inherited diseases that includes hip dysplasia.  Breeders should take note if OCD occurs in a family of dogs in which hip dysplasia is a problem.  Dogs with OCD should not be bred.

How do I manage OCD in my breeding program?

Do not breed dogs with OCD.  Select for dogs that are moderate in size and bone.  (It should be noted that large and heavy-boned dogs do not meet the breed standard though they are sometimes fashionable in the show ring.)  Screen all breeding stock for elbow dysplasia (OCD of the elbow is a form of ED) prior to first breeding.  If OCD is produced, do not repeat the breeding.  Breed the parents and healthy offspring only to mates that have passed elbow screening and have no family history of ED or OCD in any joint.

What is patellar luxation?

Luxated patellas are also sometimes called genu valgum or slipped patellas.  The patella is the kneecap, which is located on the front of the stifle joint.  Luxated patellas result from improper formation of the groove at the lower end of the femur in which the patella slides when the stifle joint is flexed and straightened.   One or both stifles can be affected.  In larger breeds like the Aussie the luxation is lateral (to the outside.)  Sometimes patellar luxation can be caused by injury, but a vet would be able to detect that. The condition can be associated with straight stifles, ruptured cruciate ligaments, and hip dysplasia.  Patellar luxation can lead to degenerative joint disease in the stifle in older dogs which is painful and can cause lameness.

Isn’t this a toy breed problem?

Luxating patellas may be more frequent in toy and small dogs, but they occur in larger breeds, too.  Great Pyrenees, are one example. Unfortunately, they happen in Aussies, too.

How common is patellar luxation in Aussies?

It is rare.

How can I tell if my dog has patellar luxation?

Dogs with patellar luxation have abnormal carriage (the stifle will be kept flexed and the foot may or may not touch the ground) or abnormal gait in the hind limbs (crouched, bowlegged stance with inward-turned feet).   It is diagnosed with a manual exam.

Is patellar luxation inherited?

Yes.  The inheritance appears to be complex.

How do I manage patellar luxation in my breeding program?

Do not breed an affected dog.  Breed for correct angle of the stifle joint to minimize risk associated with straight stifles.  Don’t repeat the cross that produced it or breed either parent or the siblings of an affected dog close on their own pedigree or to anything with a family history of luxating patellaas, bilateral cruciate rupture, or hip dysplasia.  Screen patellas on all your breeding stock related to the affected pup and all puppies from those dogs before they leave.  Do hip screening on all breeding stock (this should be standard for Aussies.)

How is natural bob tail (NBT) inherited?

The gene known to cause bob-tail in Pembroke Corgies has been found in Aussies.  It is an incomplete dominant, like merle.  Puppies that inherit two copies die early and are reabsorbed.  Dogs with one copy are NBT.  This gene does not determine tail length in NBTs nor whether the tail is straight or crooked.  Those traits may be controlled by other genes or regulatory DNA.

 Is it OK to breed two NBTs together?

No, particularly if they are very short NBTs.  Doing so can produce puppies with spina bifida or other lower spinal cord defects; something similar occurs in Manx cats. The 2009-10 ASHGI health survey found that 2% of breeding dogs were reported to have produced NBTs with defects bad enough to require euthanasia. Given that this is a percentage of all the breeding dogs in the survey many of whom were not NBT, actual percentage in NBTxNBT crosses might be even higher.  A lesser problem with NBT x NBT breedings is the risk of small litters due to reabsorbtion of fetuses.  In a breed that has sizeable litters the difference may not be noted and in any individual litter the effect might be negligible though it could also be pronounced, depending on the fall of the genetic dice.

 How common is NBT in Aussies?

27% of the dogs in the 2009-10 ASHGI health survey were NBT.  However, as of January 2003 18.41% of Aussies registered with ASCA had NBTs.  There was no significant difference between males and females, however dogs born during the 70s were more likely (23.04%) to be NBT.  Dogs born from 1990 on made up a majority of the data set and are therefore not significantly different from the overall average.  The difference between early and more recent ASCA dogs may mean breeders had selected away from NBTs in the interim.  It could also be due to failure to report the trait.  The much higher numbers for the ASHGI survey may be a reflection of this, though they may also be an artifact of a smaller data set.  With all that under consideration, one can probably make a reasonably accurate estimate of somewhere between 20% and 25% NBTs in the breed.

How short does a tail have to be for it to be natural bob?

Normal tail length varies considerably between breeds.  Presumably all individuals within a breed will have the same or very similar tail set and number of vertebrae in a normal tail.  Normal tails taper; the vertebrae get smaller as you move toward the end, giving the impression of a point.  In a bobtail, some number of vertebrae are missing so the end of the tail will be somewhat blunt–how blunt will depend on how short the bob is and whether the final bone is misshapen.  The 2009-10 ASHGI health survey also asked respondents about tail length.  Of the NBTs whose tail length at birth was known, slightly less 47% were quarter length or longer with 3 out of 5 of those having half- or ¾- length tails.

How common are crooked or kinked tails and how are they inherited?

10% of the NBT dogs reported to the 2009-10 ASHGI health survey had kinked tails.  Only one was reported in a dog that was not NBT so the association with bobbed tails is strong.

What is the proper tail (carriage, shape, and feathering) for an Aussie? 

At this point (2013) the breed standards do not address this.  It is very important that different countries DO NOT adopt different standards for tails and that those standards, when developed, reflect what is typical of the breed rather than what prominent individuals might prefer.  The 2009-10 ASHGI health survey was international in scope, so included a number of full-tail dogs.  Owners were asked about tail carriage, shape, and feathering.  A typical tail is slightly curved with feathering shortening from base to tip.  Tail carriage was less definitive though high over the back was clearly atypical.  Most were reported to carry their tails slightly above or slightly below the topline (level with the topline was, oddly, reported in only a minority of dogs) and a significant minority (21%) were reported to carry the tail low.

What is cleft palate?

Cleft palate is a developmental defect in which the midline of the palate fails to close before birth.  The opening can extend forward to separate the incisors and up to the nose, sometimes branching into each nostril.

How do I know if my dog has cleft palate?

In most cases it will be noticed at birth, however if the opening is only in the palate and doesn’t involve the front of the upper jaw or nostrils it might escape notice, though the puppy won’t be able to nurse normally and may be discovered if the breeder looks into the mouth.

What does cleft palate mean for my dog?

Cleft palate puppies have difficulty nursing and risk aspiration pneumonia when milk is inhaled through the open nasal cavity.  Survival rate is poor.  Smaller clefts may improve as the puppy grows.  Surgical correction is possible but expensive.  If the dog survives past puppyhood and does not have an opening from the mouth to the nasal cavity it will probably be fine.  If an opening remains, it will require constant care when feeding to prevent aspiration of food.

How common is cleft palate in Aussies?

It is rare.

Is cleft palate inherited in Aussies?

Probably not.  Cleft palates can occur for a variety of reasons, only some of which are genetic.  If there is no prior history of cleft palate in related dogs it is unlikely to be inherited.  Non-hereditary causes include toxic exposure at a critical point in development or an “accident of development” in which something went wrong for unknown reasons.

The only clearly hereditary cases of  cleft palate in Aussies were associated with a syndrome of multiple skeletal anomalies, including cleft palate.  All those dogs were descended from a single female outside the mainstream of the breed.  Few, if any, remain alive today.  In Europe, where someone probably found research papers published on the condition,  it is referred to as “skeletal lethal.”

What does cleft palate mean for my breeding program?

So long as there is no familial pattern of occurrence, it isn’t a breeding concern.  If it is familial, don’t breed affected dogs, don’t repeat the breeding, and breed all near relatives only to dogs from families where it is not known to occur.

What is Skeletal Lethal?

Several scientific papers were published in the 1980s and early 1990s about a syndrome of multiple skeletal anomalies, including cleft palate.  In Europe it has been referred to as  “skeletal lethal.”   This was due to an X-linked mutation that arose in a single female dog.  All male offspring that inherited the mutation had severely deformed skeletons and cleft palate.  All but one died shortly after birth.  Females with a coup of the mutation had crooked long bones in the legs and polydactyly and/or fused toes.  Few, if any, of these dogs remain today.  It should not be considered a breed health issue.

If a dog has extra toes on its rear feet that are right alongside the regular toes, are they dewclaws?

Probably not.  Extra toes, or polydactyly, occur occasionally in dogs though it’s more common in cats.  The most frequently seen cases in dogs involve rear and/or extra dewclaws which do not touch the ground when the dog is standing normally.  Dogs will sometimes have polydactyly involving other toes.

There is an example of polydactyly in Aussies.  In the 1980s an X-chromosome linked genetic disease that caused multiple skeletal anomalies was identified.  Females with a copy of the mutation had extra or fused toes.  Most of the references to polydactyly in Aussies you will find in scientific literature relate to these dogs, all members of a single family.

What are dewclaws?

Dewclaws are fifth toes on either front or rear legs.  They emerge along the side of the lower leg and do not touch the ground when the dog is in a normal stance.

Can a dog have multiple dewclaws on one leg?

Yes.  Double rear dewclaws are required in some breeds.  Sometimes a dog may have triple rear dewclaws. Multiple front dewclaws are abnormal.  Rear dewclaws are abnormal for members of the dog family in general (wolves, foxes, etc.), but do occur in domestic dogs.  Whether they are “normal’ or not depends on the breed.  They are not normal in Aussies.

 Why should rear dewclaws be removed?

Front dewclaws are allowed to be removed per the breed standards, but shouldn’t be for functional reasons.  Rear dewclaws, remnants of the first toe, are non-functional and should be removed in breeds where they aren’t required (including Aussies.)  Rear dewclaws do not attach to the other bones in the rear legs.  They are encased in flaps of skin that protrude from the leg and lack continuity with the remainder of the skeleton.  In field conditions they may snag on things and tear.

 How common are rear dewclaws in Aussies?

There are no statistics on rear dewclaws, but they don’t appear common.  However, they obviously occur often enough – or at least did historically – for them to merit mention in the breed standards.

How are rear dewclaws inherited?

Unknown, but since they are characteristics of some breeds, they are inherited.

How should I handle rear dewclaws in my breeding program?

They should be considered faulty and bred away from.

 Why shouldn’t front dewclaws be removed?

People do it for easier grooming or to make the front leg look smoother; some feel it presents an unnecessary risk of injury to dogs working in rough terrain.  The breed standards allow it but there is compelling reason not to remove them.

The front dewclaws are equivalent to our thumbs. 

Even though these toes don’t reach the ground when a dog is standing or trotting, they are functional, stabilizing the carpal (wrist) joint, especially when moving at speed or making sharp turns.  They are used for self-grooming and to help steady objects a dog may hold between its forepaws when lying down.  All but one wild dog species (the African Wild Dog or Painted Wolf) have front dewclaws, including all those most closely related to domestic dogs.

Removing front dewclaws can impact health:  Physically active dogs which have had the front dewclaws removed are prone to developing arthritis at the carpal joint, sometimes sufficiently severe and early to end a performance event or working career.

What is Spondylosis?

Spondylosis is a degenerative disease of the spine due to age or injury.  Affect dogs develop bone spurs on the vertebrae, sometimes bridging them.

How do I know if my dog has Spondylosis?

Initially dogs are asymptomatic, though you may notice protrusion of the bone spurs.  Over time the dog will begin to exhibit pain, stiffness, and restricted motion.  Spondylosis can be confirmed with an x-ray.

What does having spondylosis mean for my dog?

Spondylosis is degenerative and can cause pain.  Severe cases can impinge on nerves and may require surgery.  For the less affected, it is necessary to restrict activity and manage the pain.

Is spondylosis common in Aussies?

It is somewhat common in older dogs, possibly because Aussies live such active lifestyles.

Is spoldylosis inherited?

In some breeds it is, which indicates that it may be genetic in Aussies in some cases.  However, given that it is almost always reported in older (7 years plus) Aussies points to an aging and/or wear and tear issue.

 What does Spondylosis mean for my breeding program?

Unless you are seeing it in multiple related young dogs it is unlikely to be a breeding concern.

What are transitional vertebrae?

Congenitally malformed vertebrae situated at junction points between distinct segments of the spine where the vertebrae change shape, as from the ribcage to the lower back or lower back to the hips.  This last, the lumbosacral region is the place most transitional vertebrae occur in dogs.  Transitional vertebrae will have characteristics typical of both spinal segments.

How do I know if my dog has transitional vertebrae?

They will be noted on x-rays, commonly when hip x-rays are done but possibly when x-rays are taken for diagnostic purposes and the spine is included in the frame.

What does having transitional vertebrae mean for my dog?

OFA states that “transitional vertebrae are usually not associated with clinical signs.” However, there are reports of Aussies with degenerative disease of the spine in the area of the transitional vertebrae.  It may be that these abnormal vertebrae can be subject to increased wear-and-tear in physically active dogs which engage in activities that require spinal flexibility.

Are transitional vertebrae common in Aussies?

Unknown.  While they are recorded in some hip x-ray screening reports there is not currently any statistical database that tracks them.  They are probably not very common, but not very rare either.

Are transitional vertebrae inherited?


What do transitional vertebrae mean for my breeding program?

Treat them as a fault and don’t breed dogs with transitional vertebrae to mates with a family history of transitional vertebrae.

What is dwarfism in dogs?

It depends on what you mean by “dwarf.”  If a dog has normal proportions but is unusually small, it could be due to any number of things.  The size of dogs varies tremendously.  Some breeds are normally very small and others very large.  However, unusually small stature combined with normal proportions could be due to poor nutrition in puppyhood or underlying health problems.    The most common type of dwarfism in dogs is chondrodysplasia. It is “normal” for some breeds (Corgis, Bassets, etc.) but obviously not for Aussies.

Breeders can alter a breed’s proportions if a long and low look becomes stylish by selecting for dogs with less leg and/or longer backs.  Body outline, for all breeds, is described in the breed standard.  Anything that significantly alters the correct proportions for the breed, whether longer and lower or shorter and higher, is breeding against the standard.

Are Mini Aussies dwarfs?

Miniature American Shepherds (aka Mini Aussies) are a smaller type of dog with a normal canine body outline.  Their size difference isn’t due to dwarfism but because breeders selected for a dog that looks like an Aussie but is significantly smaller.

What is chondrodysplasia?

Chondrodysplasia is a type of dwarfism in which the dog’s long bones fail to extend during growth periods.  It’s normal in breeds like Bassets, Dachshunds, and Corgis.  If a dog’s legs are very short but his body and head are normal sized, it has chondrodysplasia.

 How do I know if my dog has chondrodysplasia?

Chondrodysplastic pups can’t be distinguished at birth from other pups.  The disease prevents growth of the long bones so isn’t noted until the pups start to grow.  If puppies are very tiny at birth, it could be due to any number of things.  If they are otherwise progressing normally they may catch up in size.  If their behavior is in any way abnormal, something is wrong and you should get them to a veterinarian.

 What does chondrodysplasia mean for my dog?

Chondrodysplastic puppies can live normal lives.  It is extremely incorrect for an Aussie, but the dog itself should be fine.  Dachshunds sometimes have back problems, but this is due to the exaggerated length of their backs in relation to height; most chondrodysplastic dogs do not have such proportionally long backs.

How common is chondrodysplasia in Aussies?

It is rare.

 Is chondrodysplasia inherited?

Chondrodysplasia is recessive.  If a dog has it, its parents are carriers.

 Is there a DNA test for chondrodysplasia?

There is a DNA test for chondrodysplasia in Norwegian Elkhounds, but it apparently does not apply to other breeds.  This indicates that there is more than one genetic factor that causes or contributes to the trait.

 What does chondrodysplasia mean for my breeding program?

For now, the best breeders can do if they get chondrodysplastic offspring in a litter is not repeat the breeding and in future breed the parents, normal siblings and other close relatives only to dogs with no family history of this defect.

What is a cranial cruciate ligament rupture (CCL)?

Cranial cruciate ligament ruptures are the most common stifle problem in dogs.  The cruciate ligament stabilizes the stifle joint by keeping the femur (thigh bone) and tibia, the leg bone below the stifle in proper orientation.  Ruptures occur due to ligament degradation over time.  A wide variety of factors play a role in this, probably including some degree of heredity.

How do I know if my dog has a cranial CCL?

Affected dogs exhibit lameness in the affected leg and an unstable gait.

How is CCL diagnosed?

In some cases diagnosis can be made by manipulation of the joint.  X-rays and ultrasound may also be used.

What does having CCL mean for my dog?

The condition can be extremely painful and requires treatment.  In a dog the size of an Aussie, surgery is necessary to stabilize the joint.  If surgery cannot be done for some reason, a knee brace may help.  This is a career-ending injury in a working or performance dog.

How common is CCL in Aussies?

Common.  According to the ASHGI Health Survey about 2.5% are affected, with a third affected in both stifles.  The unilateral cases were almost all on the right.

Are cranial cruciate ligament ruptures inherited?

To some extent they probably are.  If multiple cases have occurred in a family of dogs, a hereditary component should be assumed to be involved.

What do cranial cruciate ligament ruptures mean for my breeding program?

 If multiple cases have occurred in a group of related dogs, affected dogs should not be bred.  Their first-step relatives (parents, offspring, full and half siblings) should be bred only to mates with no recent family history of CCL.

 What is panosteitis?

Panosteitis, sometimes called “pano,” is an orthopedic disease causing inflammation in the long bones of the legs in young (5-18 month old) dogs.  Usually large dogs are affected, but it can occur in any breed including the Australian Shepherd.

 How do I know if my dog has panosteitis?

The dog will be lame in one or more limbs, usually in the forelegs but hind legs may also be affected.  Lameness may occur first in one leg, then another.    If multiple legs are affected at the same time the dog can have great difficulty moving around.  Some dogs have fever or loss of appetite.

How is panosteitis diagnosed?

Panosteitis can be diagnosed with x-rays, though your vet will probably also do blood tests to rule out other possible causes of inflammation.

What does having panosteitis mean for my dog?

This is a very painful disease that requires treatment.  It can last for days or months.   Pain management, through limiting activity and medication plus anti-inflammatory medications are the most common types of treatment.  The dog should be monitored by the veterinarian every few weeks during the course of the illness.  Fortunately, this disease is limited in nature and will ultimately go away on its own; treatment is aimed at maintaining quality of life for the dog during the illness.  If untreated, the dog may lose muscle mass.  In rare cases other bone diseases may develop.

 How common is panosteitis in Aussies?

It is rare.

Is panosteitis inherited?

It is generally considered to be inherited.

What does panosteitis mean for my breeding program?

Having panosteitis should be treated as a severe fault; even though affected puppies almost always recover it is painful to the dog and a significant management issue for the owner.  Do not repeat breedings that produce it.  Affected dogs, if bred, and their first-step relatives (parents, offspring, and full or half siblings) should not be bred to dogs that had panosteitis or who have near relatives who were affected.