Albert

• General

• Eyes

• Chondrodystrophy-related problems

• Joints

• Skin - the Itchy and Scratchy show

The glen health and breeding statistics quoted have been obtained from the KoiraNet database 07/08, chondrodystrophy-related facts are from a variety of sources, including an article published in the Finnish Kennel Club official magazine, breed club websites as well as from my own knowledge of the disorder in humans (I am a doctor). 

The glen of imaal terrier is a fairly healthy and robust breed as far as pedigree dogs go. It’s heavily built, rather long, has a huge head that seems to defy gravity and front legs that look as though they have bowed under the weight of that front, but even so the finished product is strong and well proportioned in its own funny way.

The glen of imaal terrier is a chondrodystrophic breed just as other short-legged breeds such as dachshunds, bassets, corgies and other long-bodied terriers are. Chondrodystrophy also occurs in humans (though in humans it is more commonly referred to as achondroplasia or chondrodysplasia). It is a recessively inherited cartilage growth disorder that results in normal growth of the head and body, but disrupted growth of the limbs. Humans have started to selectively breed dogs with this genetic defect, as short-limbed dogs have had a lot of good uses. Larger ground-dogs have fitted into and worked in fox and badger sets better, and bassets have chased slowly, tracked precisely and their masters have been able to keep up with the working basset on foot, unlike with the long-legged hounds. The chondrodystrophy-mutation is also at least in part behind the large heads and heavy build of the bull-breeds. Malformed limbs are a typical symptom of the disorder, and this is also why the glen of imaal terrier has out-turned front feet and bowed legs. The funny front legs are thus not a selected trait to make the dog dig better, as I’ve sometimes heard explained, but simply a potentially problematic by-product of being short-limbed. The dachshund, for example, has largely been rid of its crooked legs thanks to sound breeding choices. Unfortunately, the effects of chondrodystrophy aren’t limited to the cartilage of the legs, but other cartilagenous structures such as intervertebral discs and even heart valves are affected by this developmental disorder. I will return to chondrodystrophy-related health issues in more detail later.

Another major issue the glen of imaal terrier has as a breed is their small numbers. After the breed was officially recognised and out-crosses to other terriers stopped, the number of individuals used for breeding collapsed, and this has resulted in glen of imaal terriers being genetically very similar. When there is little genetic variation within a population, recessively inherited disorders, which are effectively masked by dominant healthy genes in heterogenic populations, are able to surface and cause disease. Even the current population of glen of imaal terriers is small, and good “out-crosses” are quite difficult to find and arrange due to the small number of different lineages and individuals. Also due to some what I would go as far as calling thoughtless breeding practices, the gene pool of Finnish glens is very shallow despite their numbers having soared. As a result, the inbreeding-percentage of Finnish glen litters averages at around 5-10%, which is equivalent to cousin- or half-sibling marriages. We have even had some cases of father to daughter inbreeding.

Glens have been very fortunate so far, and they do not have illnesses to the extent that they very well could with this background. On the other hand, the Finnish glen of imaal associations have not been very active in documenting glen illness and longevity, and very few official health examinations besides eye checks are conducted on glens, so we could even get some nasty surprises if this issue was examined in closer detail. The worst or at least the most discussed health issue that has surfaced in the breed is PRA, progressive retinal atrophy, which is an inherited eye condition that leads to blindness.

As of yet the glen of imaal terrier is not part of PeViSa, which is a Finnish Kennel Club directed breeding-programme to fight hereditary disease. Thus it is not compulsory to conduct ANY health examinations on breeding glens, ensuring the health of dogs used for breeding is completely up to the judgment of individual breeders.

When examining glen health statistics, the eyes unfortunately grab one’s attention. From 1990 onwards, as many as one in five (20%) of glen of imaal terriers have some form of hereditary eye condition. The most common condition is PRA (74% of cases), but hereditary cataract is also common (13%)  as is PHTVL/PHPV (13%). In addition Finnish glens have had other various eye diagnoses, which may or may not be hereditary.

If one had to choose a hereditary condition, PRA is one of the least devastating to have. As PRA usually progresses quite slowly, the affected dogs accommodate surprisingly well to their handicap and get on with life as usual. Some even fetch with no apparent problems. Glen of imaal breeders are very aware of PRA, and firm measures have been undertaken to limit its occurrence in the breed. At least in Finland as many glens as possible undergo official eye examinations, and affected dogs and their close relatives are excluded from breeding. This makes every case of PRA quite a disaster in a breed of this caliber, as a multitude of potential reproducers are overruled with each confirmed case, and some of them may not even carry the disease. It would thus be important to develop a PRA gene test for glens, whereby carriers could be identified via a simple blood test. Such a test exists for quite a few breeds already, and glen breeders are collecting samples and working hard towards the development of one for glens, too.

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There is a very unromantic explanation to the curious and rather charming appearance of the glen of imaal terrier (as well as other short-legged breeds). The typical appearance is in fact the result of a developmental disorder called chondrodystrophy, which is caused by a relatively common gene mutation, and is also the most common cause of dwarfism in humans.  Before the glen of imaal terrier became primarily a pet, the pros of this disorder outweighed the cons, as being short limbed was absolutely essential for a dog of this size to go to ground after fox and badger. Chondrodystrophy occasionally occurs as a spontaneous mutation in breeds of normal structure, and it is thus easy to picture how our short-legged breeds have arisen. Now and again there has been a funny-looking, short legged puppy in a litter, and people have noticed the potential uses of these curious creatures in tracking and groundwork. The trait is effectively dominant, and thus quite easy to breed for.

Chondrodystrophy affets cartilage metabolism, and it thus affects the growth plates of long bones, resulting in stunted bone growth that leads to short and malformed limbs. Unfortunately, metabolism is also disrupted in other cartilaginous tissues such as intervertebral discs. Chondrodystrophic discs age prematurely, and the process often begins at a very young age. The backs of chondrodystrophic dogs are more prone to injury than those of normal dogs, and, for example, the  horrific curse of dachshunds, dachshund paralysis, is a result of chondrodystrophy-related intervertebral disc disease. I am not aware of cases of paralysis in glens. However, milder signs of intervertebral problems are reluctance to exercise, avoidance of stairs, reluctance to jump, limping, all kinds of pain when for example moving the head (eg eating/drinking) or when the dog is lifted. Other signs include weak or stuttery movements, especially in the hind legs, keeping a curved or hunched posture, and even problems urinating and defeacating or incontinence.

Chondrodystrophic growth plates are sensitive to damage, which easily results in excessively distorted limbs. Many breeders and breed clubs of other chondrodystrophic breeds warn puppy purchasers against over-exerting their puppies or allowing them to engage in activities that could result in damage to the growth plates or back.

All kinds of heart-valve problems are more common in chondrodystrophic breeds than in breeds with normal proportions. If a heart murmur is heard in a long-backed dog, it should always be taken seriously and the condition of these dogs’ backs should also be assessed, as these problems often go hand in hand. It is also interesting, that the occasional chondrodystrophic individuals of normally proportioned breeds and lineages where chondrodystrophy is more common have a much higher incidence of eye disorders than their healthy counterparts.

Chondrodystrophic dogs often show intervertebral disc calcifications in x-ray imaging. These are not in themselves a problem, but act as a good indicator of cartilage malfunction and reflect the risk of developing intervertebral disease. Finnish dachshunds breeders and fanciers have undertaken a massive x-ray campaign, and dogs with severe calcifications are excluded from breeding. Surely it would make sense to look into back problems more thoroughly in other chondrodystrophic breeds as well, including the glen of imaal terrier. Dogs, especially glens, do not always show they are in pain, at least not in ways we that we would expect. A dog may be relatively asymptomatic, mainly “lazy”, but still suffer significant pain.

Chondrodystrophy is very rarely discussed in relation to the glen of imaal terrier, and health issues related to it are not seen often anough to regard them as breed specific problems. Unlike breeders of bassets (including griffon bassets) and dachshunds, glen breeders generally do not advise puppy-buyers to be cautious regarding type and volume of exercise. I find it likely that also our beloved glens have more chondrodystrophy-related back and limb issues than we currently acknowledge. Bowed limbs and the flaws in weight distribution and joint angles that they entail make the affected dogs highly susceptible to front limb arthrosis. The glen is a heavy dog and the majority of its weight rests on the front, making its front limbs particularly susceptible to problems. When a glen leads a very sedentary life, as the majority apparently (and unfortunately) do, bowed limbs are inconsequential, but if the dog is physically very active they can easily cause a lot of bother.

Pictures with permission and kind courtesy of Stephen and Christine Collins of Rhosyn Kennels, www.rhosyngsd.com

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Hips

Hip dysplasia is not exclusive to giant breeds, but in fact surprisingly common in medium and small breeds, too. Hip dysplasia is a hereditary developmental disorder of the hip joint. Rather than developing as they should, the head of the femur (the “ball”) and the pelvic acetabulum (the “socket”) end up an odd match and do not fit into one another evenly. This structural defect puts a tremendous amount of strain on the surfaces within the joint and leads to premature arthrosis. This, at worst, makes the limb useless and is extremely painful for the dog.

Hip dysplasia, as already mentioned, is classed as a hereditary disease. However, in recent years it has surfaced that the role of dietary factors in the development of the disorder may be greater than previously assumed.   As with so many other health issues, hip dyplasia is probably also one where both genetics and environmental factors are involved.

In Finland hips are graded as listed below:

A = normal
B = almost normal
C = mild hip dysplasia
D = moderate hip dysplasia
E = severe hip dysplasia

Dogs with the same hip grade can exhibit highly differing phenotypes. There are dogs with E-hips that are practically lame, but also dogs with E-hips that barely show during everyday life. As a rule of thumb, D and E hips are usually symptomatic, whereas B and C hips are generally ok. Even healthy A hips will wear with time and can develop arthrosis if the dog has led a very active life, so an exellent hip dysplasia does not guarantee a life free from arthrosis.

A minute percentage of Finnish glens have had hip x-rays (15 glens, approximately 2%). 3 were A, 8 were B, 2 were C and 2 were D. Because the x-rayed sample was so small, no conclusions can be drawn regarding the state of glen hips on a larger scale.

However, the glen is a rather heavily built dog, and it would seem sensible to pay attention to hip matters before any problems surface. Hip dysplasia has raised its ugly head in several medium-sized dog breeds that have been assumed healthy, and thus hips have not been examined or concentrated on when breeding choices have been made. Standard schnauzers are a good (or rather a cautionary) example. The average percentage of hips graded A has gradually decreased from 56% in 1988 to only 16% in 2005. So what does it matter if there are dogs with B or C hips, if they are rarely symptomatic? It matters, as B hips and E hips are simply different manifestations of the same disease. If there are high numbers of B and C hipped dogs in a population, it is only a matter of time before D and E hips become more common.

Hip dysplasia is not inherited as simply as say a coagulatory disorder, which either is or isn’t, but rather it is a polygenetic disorder. A dog inherits a degree of hip dysplasia susceptibility, but the final manifestation on the hip joint depends on the presence and interaction of a multitude of genes, as well as on diet and exercise. Hip dysplasia is thus difficult to predict in individuals, but its risk is more easily evident in populations and lineages.

As a complicating end note I must also say that in hip x-rays “looseness” or “laxness” of the hip joint worsens the grade they get. Laxity is not necessarily a sign of dysplasia, and in some individuals laxity is simply an intermediate stage of development that will pass with age. This is why we sometimes see dogs with grade D hips as a 2-year-old, but grade B hips when they are 5. Some have loose joints simply as an individual characteristic, with no connection to hip dysplasia as such. These individuals may get a poor hip grade, such as C or D, without in fact having hip dysplasia.. In the previous paragraphs I have overlooked this issue in my explanations for the sake of simplicity.


Elbows

Elbow dysplasia is a similar condition to hip dysplasia, the location is just different. Even fewer glens have had their elbows x-rayed than hips, so there is practically no information available regarding glen elbows. All three x-rayed dogs had healthy elbows.

Knees

Surprise surprise, only very few glens have had their knees x-rayed. 92% of x-rayed dogs had healthy knees and 8% had almost healthy knees.

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The glen owner grapevine has led me to understand that an alarmingly high number of Finnish glens suffer from paw and skin problems.

The typical problem with paws is redness, itching and sores during spells of wet weather. With some the situation has progressed to being so painful that the dog is reluctant to walk and limps. The condition is not as severe as in furunculosis, but a somewhat milder disorder that is not as deep reaching in the tissues. There is no cure, and the susceptibility to paw problems typically follows the dog throughout its life. Good general care, ie keeping the paws clean and dry, is the best way to manage the situation. If the situation gets very bad, the vet may prescribe local antiseptic ointments and powders, or sometimes even oral antibiotics. Some dogs have had help from a change of diet.

Other types of itches are, unfortunately, also an everyday occurrence for some glens. The itching is very irritating to the dog, and often leads to secondary bacterial infection as sratching disrupts the immune barrier of the skin. This is often the start of a vicious cycle of itching->scratching->infection->more itching -> spread of infection -> more scratching etc. At worst antibiotics disrupt the situation even more when yeast kicks in. Trying to identify the fundamental cause of the itch can be a time and money consuming project: allergy investigations are expensive, elimination diets are painstaking and expensive. The wallet lightens and stress levels soar even further if an allergy IS identified and the vet advertises a high-price unpalatable bag of allergy-food, and the dog STILL scratches itself. Quite often the true cause of the itching remains elusive, and no explanatory allergies are found. Often certain foods such as wheat and beef make the symptoms worse, even if allergy has been excluded.

Various vague inflammatory ear and eye problems seem to typically belong to this category of scratching problems, too.

We must bear in mind that these types of problems are extremely common in most breeds of dogs, not glens alone. The hobbyist’s gut feeling is, however, that these problems prop up in glen conversation unacceptably often. Many terriers, such as the westie, are infamous for their skin issues. I believe breeders are making a huge mistake if they choose to ignore itching, allergies and paw problems when making breeding choices. At least in humans atopic and allergic tendency is highly hereditary. I see no reason to assume that this wouldn’t be the case in dogs. The baroque legs of the glen also give it a structural susceptibility to paw problems, but this is also an issue that should be addressed when making breeding choices.

At first itching and paw problems may sound very benign. In reality they can be very stressful for both dog and owner and severely affect the dog’s quality of life. The dog must endure constant itching and burning, and both owner and dog are exhausted by the washing, medicating, socks, ointments and investigations. Sometimes paw problems may even limit the amount of exercise the dog gets. Itching results in a lot of bother for the dog, a lot of grief for the owner and a huge amount of time, money and effort is consumed. In comparison, the slowly and painlessly progressing PRA can easily begin to seem like childsplay.

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