WHAT DISEASES DO LABRADORS SUFFER?

Labrador Retrievers are victims of a range of diseases and conditions, but not more than other breeds.

24 Diseases and Conditions Labrador Retrievers suffer

It is easy to form the impression that Labradors are more inclined to disease and inherited conditions than other breeds, but that would be wrong.

More attention is given to Labradors and more research may be done on the breed because of its popularity as a pet and family member.

This could lead to misconceptions about the health of Labradors as a breed.

Osteoarthritis 

Osteoarthritis is a common disease that can be observed in the effect it has on dogs and humans and which has its basis in a range of joint disorders.

Research shows that osteoarthritis is one of the more common degenerative diseases in dogs, including Labrador Retrievers.

It leads to structural and functional decline of the joint and results in lameness and pain.

The condition affects the connective tissue that provides a smooth lubricated surface for fluent and painless movement of the joints.

More than 20% of all dogs older than 1 year in the USA suffer from osteoarthritis and more than 6% (and suspected much more extensive) in the UK.

Secondary osteoarthritis (SO) is the most common form in dogs. So is the result of underlying disease or injuries.

It is believed that diet, exercise, and genetics all play a role in developing osteoarthritis in dogs.

Hip and elbow dysplasia can also contribute to the development of osteoarthritis.

There are six key risk factors associated with osteoarthritis and other canine joint diseases:

Genetics

Secondary hip joint osteoarthritis is inherited additively (parents transmitting small effect variants of genes to their offspring).

The cumulative effect over generations is that secondary hip joint osteoarthritis becomes more prominent in every generation.

It could be possible to test for the presence of the gene and to reduce, and eventually get rid of, the hip joint osteoarthritis gene in purebred Labradors.

It would result in improving breeding programs and the quality of life for dogs and their owners. Read more about the research done on this topic.

Conformation required by breed standards

Breed standards are descriptions of the features of the ideal example of breeds.

Labrador breed standards describe the ideal Labrador Retriever features based on the purpose for which the Labrador is bred.

Breed standards may require specific features which then get intensified by repeated breeding for those features.

Eventually, the feature may become over-emphasised which may lead to negative results.

Conformation breeding standards are increasingly based on the role change pets, especially dogs, have undergone in recent times.

These consider the family dog a family member and not merely a pet or property.

One aspect that influences the practice of animal breeding, is the development of genetic testing.

Genetic testing was not around when breeding standards were initially formulated and these standards still mostly do not make provision for using genetic research and evaluation in breeding standards.

Every breeder wants to have breeding material from the dog that wins the prizes because that is the best representation of the specific breed at that time.

This however results in many offspring from one popular sire and an increasing number of dogs becoming close relatives.

This may strengthen the breed as far as breed features are concerned but also means that any unknown weaknesses (that may only surface after many generations) also become overemphasised.

This was the case with dog breeds affected by degenerative myelopathy.

Breed

The breed features are dictated by breeding rules and are an integral part of what makes a modern dog breed, including Labradors.

This may contribute to certain weaknesses being transmitted to the offspring of breeding pairs just as it intensifies the good traits of a breed.

In 2015 in the UK, Labrador Retrievers have been known to have 55 known disorders and conditions such as hip dysplasia are fairly common inherited conditions in Labrador Retrievers and other breeds.

Osteoarthritis showed a high prevalence in Labrador Retrievers in the UK.

Bodyweight

Increasing body weight was also found to have an association with joint disease, most likely due to the increased load on joints.

Sex and neuter status

The existing research has not confirmed possible risk factors such as age and neuter status and more research will hopefully give more certainty.

It may contribute to the occurrence of osteoarthritis due to increased weight in neutered dogs and because neutered dogs tend to be older.

Age

Age has not been proven to contribute to the onset of osteoarthritis mainly because it is difficult to ascertain when the condition first occurred.

Other notable risk factors are the month of birth and early life factors such as exercise levels and type.

The risk posed by the month of birth probably has to do with months that offer more favorable weather for exercise opportunities at a young age which increases the risk of joint disease development in later life.

Risk factors for canine osteoarthritis

Research indicates a strong relationship between joint disease and certain genes that influence growth, musculoskeletal development and breed as well as breed standard requirements.

This knowledge can highlight individual “at-risk” dogs.

Dysplasia

Dysplasia is a term used to describe the presence of abnormal cells within a tissue or organ.

There are around 400 conditions of skeletal dysplasia in humans, but dogs in general, and Labradors in particular, suffer mostly from only a handful of these conditions.

Retinal dysplasia/oculoskeletal dysplasia 1 (SD1)

This dysplasia is an inherited collagen disorder affecting Labrador Retrievers and is observable as dwarfism and eye abnormalities in puppies of 4 – 6 weeks old.

It leads to dwarf or “mini” dogs and is a dysplasia with serious health effects for the dog. SD1 leads to malformed (bent) legs and large heads and eventually results in hip dysplasia.

Skeletal dysplasia 2 (SD2)

Skeletal dysplasia 2 (SD2) is an inherited disorder that causes a mild form of dwarfism consisting of short legs with normal body length and width.

Elbow dysplasia

Elbow dysplasia is an encompassing term for a range of conditions.

There are three common developmental problems that are often referred to as elbow dysplasia, namely a fragmented coronoid process (FCP), an ununited anconeal process (UAP), and osteochondritis dissecans (OCD).

Elbow dysplasia is the most common dysplasia in Labrador Retrievers followed by hip dysplasia.

Elbow dysplasia occurs in many dog breeds, not only Labradors.

It is so prevalent that The International Elbow Working Group was formed to increase the knowledge on and awareness of elbow disease in dogs.

Hip dysplasia

Canine hip dysplasia (HD) is a common polygenic trait characterized by hip malformation that results in osteoarthritis (OA). It causes pain and lameness.

It is a common condition among humans and dogs and leads to osteoarthritis in both species, although the Labrador Retriever demonstrates a 3.4-fold increase in risk for the development of HD and seems to have a genetic predisposition for the disease.

A DNA test was developed for the early detection of canine hip dysplasia which can contribute to the early detection of the presence of the gene in breeding dogs.

Hip dysplasia is caused when cartilage, which is displaced by bone to form the skeleton, suffers disruptions in the proteins and molecules that give structure to the cells and tissue in the body (extracellular matrix) which then lead to disturbance of bone formation.

The condition is so prevalent that the British Veterinary Association already screened more than 250 000 dogs from different breeds for hip dysplasia.

Skeletal dysplasia can be the result of an inherited or spontaneous genetic mutation.

The treatment is a hip replacement.

Copper-associated chronic hepatitis (CACH) and copper-metabolism disorder (copper toxicosis)

Copper toxicosis is a metabolic disorder that can cause chronic liver failure and neurological problems that result from deviations in normal levels of copper in the body.

Copper is necessary for the body to make red blood cells and keep nerve cells and the immune system healthy.

Copper deficiency is known as Menkes disease and excess copper is known as Wilson disease. Both diseases occur in Labrador Retriever and Labrador Retriever cross-breeds.

The liver manages copper content in the body and excretes excess copper in the bile.

But when the control mechanisms of the body “malfunction” spontaneously or due to hereditary reasons, copper can build up in the body and become toxic or poisonous.

Some research indicates that Labrador Retrievers suffer from a hereditary form of hepatitis that is caused by defective copper metabolism.

Cranial Cruciate Ligament Disease (CrCLD)

The cranial ligament stabilizes the knee.

“Cruciate” refers to the ligaments arranged in an X form. If the ligament is often partially teared over time from jumps from heights and quick turns and the CrCLD progresses, it leads to a thickening of the joint and eventually osteoarthritis.

Any lameness is not necessarily the result of CrCLD but could be damage to the hip.

It is possible to test for the potential risk of a dog getting Cranial Cruciate Ligament Deficiency.

CrCLD is the most common cause of lameness in dogs. It affects the stifle and leads to limb lameness and degenerative joint disease.

The disease affects the movement of the dog because of the lameness it creates. It affects the braking and starting ability of the dog.

The preferred treatment of the disease is surgery but non-surgical treatment can also be effective depending on the diagnosis.

Medial Coronoid Disease (MCD)

Medial Coronoid Disease is a component of elbow dysplasia and causes lameness in dogs. It is a hereditary condition.

It is the fragmentation of the medial coronoid process (see image) but because there can be MCD without fragmentation (but with cracks or fissures), it is often referred to as “coronoid dysplasia”.

In one study of 38 breeds, more than 50% of dogs with MCD were Labrador Retrievers.

The term medial coronoid disease includes all the pathological changes which can be attributed to fragmentation of the medial coronoid process

Treatment can be surgical or medical. Medical showed quicker recovery times than surgical treatment although there was no difference after nine months.

Limber tail

Limber tail is paralysis of the tail in large working dogs and often occurs after swimming in cold water.

It presents as a stiff tail against the body changing into a flaccid tail. Although it appears to be painful, limber tail resolves itself within 10 days.

Limber tail is obvious in Labradors because of the specific appearance of the Labrador tail.

There is an ongoing study of limber tail which may provide more information about this condition.

Centronuclear Myopathy (CNM) in Labrador Retrievers

Centronuclear Myopathy is a hereditary disorder of skeletal muscles.

Myopathy is a muscle tissue disease. Centronuclear Myopathy is characterized by loss of muscle tone and muscle control which is visible in loss of posture and an unusual way of walking. It is also known as hereditary myopathy of the Labrador Retriever (HMLR).

The theory is that the change in the structure of the gene (mutation) occurred spontaneously in a single Labrador.

It then spread through the Labrador Retriever population. If both parents carry the defective gene, their litter will suffer from CNM.

If only one parent carried the defective gene, the offspring will not suffer from the disease but will be carriers.

A DNA test is available and diagnoses dogs affected with CNM and can also detect those dogs which are carriers, displaying no symptoms of the disease but able to produce affected pups.

It is good to test all breeding dogs to remove carriers of defective genes from the breeding population.

Tests are accessed via the American Kennel Club’s Canine Health Foundation. Laboratories are:

• Animal Health Trust, UK.
• Vetnostics, Australia.
• ASAP Laboratory, Australia.
• Animal Genetics, USA.
• DNA Diagnostics Center (in over 50 countries).
• Gensol Diagnostics, USA.
• Alfort School of Veterinary Medicine, France.
• Paw Print Genetics (USA).
• VetGen, USA.
• UC Davis Veterinary Medicine Veterinary genetics Laboratory, USA,

Not all Labrador Retrievers suffer from the condition because it is hereditary and does not occur in all Labrador families.

Congenital Myasthenic Syndrome (CMS)

Congenital myasthenic syndrome (CMS) is a neuromuscular disorder in Labrador Retrievers characterized by generalized muscle weakness and fatigue, often induced by exercise.

CMS is part of a diverse group of disorders, the congenital myasthenic syndromes stemming from a defect in transmitting signals from nerve cells to muscles.

Congenital means it is present from birth (inherited) and myasthenic means muscular weakness with abnormal fatigue. Muscle weakness gets worse with exercise.

The condition also occurs in humans.

CMS usually occur in puppies before 12 weeks and the fatigue disappears after resting.

DNA testing can alert breeders and prospective owners to the presence of CMS but only where both parents carry the gene, will the disease be active in their offspring.

Cystinuria Type I-A in Labrador Retrievers

Cystinuria type I-A is kidney stones.

One of the functions of the kidneys is to reabsorb essential minerals and proteins back into the body.

Cystine is an amino acid that builds up and forms stones instead of going back into the bloodstream if it is not reabsorbed by the kidneys.

Cystinuria type I-A is a kidney disorder in which the kidneys are unable to reabsorb cystine, leading to the formation of crystals in the urinary tract, which can cause urinary obstruction, difficulty in passing urine, and the presence of blood in the urine.

The disease occurs in humans, cats and dogs, including Labradors.

There are indications that dogs that are neutered have less risk of suffering from Cystinuria type 1-A.

The disease is inherited and dogs with parents who both carry the defective gene will suffer the disease while dogs, where only one parent carries the gene, will be carriers but not sufferers.

Cystinuria occurs more in animals in European countries than in the USA and Canada.

Because the condition is hereditary its presence in a dog or family of dogs can be identified with DNA testing.

Degenerative Myelopathy (DM)

Degenerative Myelopathy (DM), also known as chronic degenerative radiculomyelopathy (CDRM), is a disease that affects the spinal cord. It results in increasing hind limb weakness and eventual paralysis.

The disease occurs in many breeds including German Shepherds although it has been found in Welsh Corgis. Older large working dogs are inclined to get CDRM.

It seems the disease has a mutation that resembles lateral sclerosis in humans.

CDRM is not a disease that is of main concern to Labrador Retriever breeders and owners.

Degenerative joint disease (DJD)

Degenerative joint disease is osteoarthritis.

Although DJD occurs in most breeds it is nearly 5 times more prevalent in German Shepherds than in Labradors, Golden Retrievers and Rottweilers combined.

It is one of the three most prevalent disorders in Labrador Retrievers in the UK.

The disease is the gradual deterioration of the cartilage in moving joints, leading to loss of joint movement, stiffness, lameness and pain.

It often occurs together with articular diseases such as hip dysplasia (HD), elbow dysplasia (ED), or cranial cruciate ligament rupture (CCLR).

DJD is caused by trauma, infection, the body’s own immune system, or malformation during development.

There is no cure and treatment is medical or surgical. Prevention is mostly limited to responsible feeding to ensure that your Labrador does not become overweight as that places stress on the joints.

You could also give your Labbie supplements that effectively control the destruction of cartilage.

Stem cell therapy is receiving attention as a treatment for degenerative joint disease.

Indications that your Labrador may have DJD are:

• Stiffness of the limbs is noticeable when the dog changes from a lying to a standing position.
• Lethargy or sleepiness.
• Irritability when touched in areas where joints are present such as the hips and shoulders.
• Unable or unwilling to jump into a car or onto furniture.
• Difficulty or refusal to walk up stairs.
• Loss of interest in previously liked activities such as walks or chasing.

Exercise-Induced Collapse (EIC)

Exercise-induced collapse is a genetic neuromuscular disorder characterized by muscle weakness, lack of coordination, and life-threatening collapse after intense exercise in otherwise apparently healthy dogs.

It causes dogs to collapse after intense activity or strenuous exercise and may lead to death although most dogs recover after resting.

Exercise-induced collapse is an autosomal inherited disease which means the Labrador inherited a mutation in a gene that gives them a higher chance to develop EIC.

Autosomal inheritance occurs in cancer, cystic fibrosis and sickle-cell disease in humans.

EIC starts at an age of around 12 months in Labradors. Some dogs develop an abnormal walk because the rear limbs become weak and unable to support the dog’s weight.

Research showed that 5 – 20 minutes of strenuous exercise with extreme excitement triggers the collapse.

Complete recovery happens after 5 – 25 minutes with no after-effects.

Three factors play a role in EIC in Labradors:

• Temperature or humidity that is much higher than what the dog is accustomed to, although dogs have collapsed and died after retrieving in frigid waters. Death will rather occur in dogs during land-based rather than in swimming activities.
• Dogs that have symptoms of EIC, usually have excitable personalities, and research indicates that their level of excitement plays a role in triggering the collapse.
• Exercise type. Activities that demand intense exercise, particularly if it is accompanied by a high level of excitement or anxiety can be expected to cause collapse. Routine exercises do not induce collapse.

Most Labradors that suffer from EIC are removed from active life and become pets.

Treatment of Exercise-Induced Collapse starts with avoidance of intensive exercise and excitement.

Other medicinal treatments are available and should be discussed with your Vet, but do not expect miracles at this stage.

Exercise-Induced Collapse and Heatstroke

Heatstroke is much more serious than EIC. It requires longer recovery times and often lead to additional complications such as renal failure.

Because EIC is hereditary, it means that a dog with active EIC inherited the condition from both parents.

A dog that inherited the gene from only one parent will be a carrier but not a sufferer and a dog from “clean” parents will neither have EIC or be a carrier.

Source (pdf download)

Hereditary Nasal Parakeratosis (HNPK)

Keratinocytes form the outermost layers of the skin. Keratin is the material for nails, hair, claws, horns, hooves etc.

Hereditary nasal parakeratosis is a genetic defect that affects specialized cells of the canine nose, resulting in the formation of a crust with cracks over the nasal area of young dogs.

It is a disease of the skin that leads to the formation of a crust with cracks over the nasal area of young dogs. Dogs with HNPK develop dry, rough, gray to brown crusts and cracks on the tip of the nose. It may make bacterial infections more prevalent.

Twenty-five percent of the offspring of two carriers can be expected to have HNPK. The presence of genes that could lead to HNPK can be identified with gene testing.

Hereditary Nasal Parakeratosis is not fatal and the health of an affected dog is not otherwise in jeopardy.

Hyperuricosuria (HUU)

Hyperuricosuria is an inherited disorder that leads to excessive uric acid in the urine which causes the formation of bladder and kidney stones.

Bladder and kidney stones are mostly removed with surgery and the best prevention is diet management.

The presence of the disorder can be found with a gene test because it is a hereditary disorder.

All canine breeds are affected and it is not more prevalent in Labradors than in other breeds.

Narcolepsy in Labrador Retrievers

Narcolepsy in Labrador Retrievers affects the brain’s ability to control sleep and wake cycles.

It is a sleeping disorder characterized by
daytime sleepiness,
disrupted sleep patterns, and
quick-passing episodes of muscle weakness or paralysis triggered by play or food.

It also manifests as the sudden loss of muscle tone and collapse without loss of consciousness which is triggered by strong positive emotions such as play and food.

Narcolepsy is autosomal recessive so both parents need to carry the defective gene for the offspring to suffer from it.

If one parent carries the gene and the other parent lacks it, the offspring will be just carriers and not sufferers.

The disease is rare in Labradors.

Pyruvate Kinase Deficiency (PKDef) in Labrador Retrievers

Pyruvate kinase deficiency in Labrador Retrievers is a chronic, severe hemolytic anemia caused by the defective production of an enzyme called pyruvate kinase.

Pyruvate kinase is an enzyme necessary to produce energy. Signs in affected dogs may include a lack of energy, low endurance, and fatigue.

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Hemolysis means the destruction of blood cells.

Anemia means the red blood cells are not replaced at the same rate it is depleted.

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The disease was first identified in Basenji dogs, occurs in cats, but does not occur extensively in Labrador Retrievers.

It has an occurrence of less than 1% in Labradors. Breeds that are affected are Beagle, Cairn Terrier, Labrador Retriever, Pug and West Highland White Terrier.

A gene test can confirm the presence of the gene that creates PKDef.

Progressive Rod-Cone Degeneration (PRA-prcd)

Progressive rod-cone degeneration (PRCD) negatively affects the photoreceptor cells in the eye. It is an inherited condition that has been identified in many dog breeds.

It starts with night blindness and leads to color blindness, daylight blindness and eventually total blindness. PRA-prcd can be confirmed with a gene test.

PRA-prcd is the animal version of retinitis pigmentosa in humans.

In Japan, the disease was found to be more widespread in the general Labrador population than in the guide dog population.

Skeletal Dysplasia 2 (SD2) in Labrador Retrievers

Skeletal dysplasia 2 (SD2) is an inherited disorder that causes a mild form of disproportionate dwarfism consisting of short legs with normal body length and width.

The condition occurs in Labrador Retrievers and Labradoodles and is hereditary. A test can confirm the presence of the gene that causes the disease.

Stargardt Disease (STGD) in Labrador Retrievers

Stargardt disease is a degenerative eye disorder or retinal disease resulting from the gradual loss of the photoreceptor cells that are responsible for sensing light.

Affected dogs show a decline in vision with age but appear to retain some vision throughout their life. It is a disease that affects dogs as well as humans.

A variant of the disease was first identified in Labrador Retrievers and a test can confirm the presence of the causative gene.

Genome sequencing in Labradors led to the identification of a similarity with human STGD.

X-Linked Myotubular Myopathy (XLMTM) in Labrador Retrievers

X-linked myotubular myopathy in Labrador Retrievers is an inherited muscle disease that leads to muscle weakness and progressive muscle atrophy in puppies.

Features of XLMTM

• Occurs as early as 7 weeks of age.
• Muscle weakness.
• Progressive muscle atrophy.
• A hoarse bark.
• Episodic collapse.
• Droopy jaw.
• Difficulty eating.

Although the disease is rare (it affects less than 1% of the population) and seems to be limited to Canadian Labradors, testing for the presence of the gene is available. Source

XLMTM is a model of the human condition.

All dogs that suffer from this condition are eventually euthanized.

How do Labradors get diseases?

Labrador Retrievers get diseases from the same sources as any other breed of dogs, but Labradors have a unique temperament which may expose them to other risks.

A large percentage of diseases and conditions stem from hereditary sources, some occur spontaneous in single dogs and are then transferred via breeding to become a hereditary condition and some are natural occurrences in most breeds of dogs.

Hereditary conditions seem to be unintended consequences resulting from the breeding of Labrador Retrievers to enhance certain traits.

Why do Labradors get diseases?

Labradors get diseases for the same reason that other animals and humans get diseases and other health conditions.

Any human, animal, insect, or plant suffers from diseases because they are all living organisms.

Labradors, just like other pure-bred animals run the risk of genetic disorders and weaknesses mostly due to breeding aimed at enhancing specific traits for activity, show, or human cosmetic crazes.

See Increased Prevalence of Inherited Disorders in this research paper and read about teacup dogs.

When and where do Labradors get diseases?

Labradors get diseases at any time of their lifecycle but inherited diseases are present at birth, although it may only become visible later in life.

Much depends on the disease or condition as some conditions affect puppies, some adult dogs, and other conditions affect old dogs.

Environmental factors also play a role in when Labradors get sick. The climate, severe weather conditions, stress, virus particles such as the dog flu virus, bacteria, contaminated dropping of other dogs, internal and external parasites, pesticides used in a home, fungal infections from contaminated soil, heartworms from mosquitoes, injury, rabies, and fungal infections all make dogs sick at any time they come in contact with the source of the disease.

How to cure diseases in Labradors

The most reliable way to cure disease in your Labrador is to take it to a Vet at regular intervals, and without waiting when something seems out of the ordinary.

Every condition and disease, with a few exceptions, that your Labrador may suffer from can possibly be successfully treated.

In our discussion of the different diseases and conditions above, we have named possible treatments, but the wise way in which to deal with any disease is to take your dog to the Vet.

Conclusion

Labradors can suffer any disease any other dog breed suffers from with an added few conditions stemming from breeding programs.

The dog an attractive species to discover genes underlying the similarity between some diseases in humans and dogs.

The high correlation of canine diseases to diseases in humans, and the importance of dogs to humans in a shared environment, make the dog a good starting point for research.

The concept of One Health is gaining popularity because of the similarities between animal and human diseases and conditions.

Human health can gain many positive results from the knowledge exchange between animal and human health researchers.

The contribution animal health research can make to human health is not a new concept, but has a history. Covid forced people to become aware of the value their pets have for them. We can expect the potential of cooperation between human and animal health to receive increased attention.

Your Labrador Retriever will suffer much fewer health problems if it is treated in the way the breed requires. The Labrador was bred to be a human companion and active working dog.

If you are a responsible Labrador owner and you make sure that your dog gets enough exercise and attention and is not obese, it will be a healthy dog.

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