Genetic Disorders Genetic Disorders

Maltese Maltese

Introduction Introduction When choosing any breed of dog you must be aware of When choosing any breed of dog you must be aware of

potential health concerns potential health concerns All dogs mixes and pure bred can have health concerns All dogs mixes and pure bred can have health concerns The more popular breeds and their mixes will have more The more popular breeds and their mixes will have more

genetic problems listed and more likely to have puppies genetic problems listed and more likely to have puppies with problems . with problems .

Although more serious in dogs under 6 lbs all sizes of Although more serious in dogs under 6 lbs all sizes of Malteses can have any of these health concerns. Malteses can have any of these health concerns.

Make sure your breeder offers a written health guarantee Make sure your breeder offers a written health guarantee good for one year.good for one year.

Have the puppy heath checked at your Veterinarian.Have the puppy heath checked at your Veterinarian.

Heart Disorders Heart Disorders Patent ductus arteriosusPatent ductus arteriosus Where the ductus arteriosus does not Where the ductus arteriosus does not

close within 24-48 hours after birth, the dog is left with a patent close within 24-48 hours after birth, the dog is left with a patent ductus arteriosus (PDA). PDA causes unnecessary recirculation of ductus arteriosus (PDA). PDA causes unnecessary recirculation of blood through the heart, greatly increasing the workload of the blood through the heart, greatly increasing the workload of the heart and potentially causing terminal heart failure in time if the heart and potentially causing terminal heart failure in time if the PDA is not closed via surgeryPDA is not closed via surgery

Mitral valve dysplasiaMitral valve dysplasia The term "mitral valve dysplasia" refers The term "mitral valve dysplasia" refers to this exact situation, where from the moment a pup is born, its to this exact situation, where from the moment a pup is born, its mitral valve does not seal properly, and therefore imposes an mitral valve does not seal properly, and therefore imposes an increased workload on the heartincreased workload on the heart A mild degree of mitral valve A mild degree of mitral valve dysplasia usually means no symptoms and a normal life, dysplasia usually means no symptoms and a normal life, whereas severe mitral valve dysplasia can produce life-whereas severe mitral valve dysplasia can produce life-threatening symptoms even in the first year of lifethreatening symptoms even in the first year of life. .

Eye Disorders Eye Disorders Retinal dysplasiaRetinal dysplasia: : The condition is present from birth. The condition is present from birth.

At 3 to 4 weeks of age, the breeder may notice that At 3 to 4 weeks of age, the breeder may notice that severely affected pups are less active and frequently severely affected pups are less active and frequently bump into objects. A veterinarian will be best able to bump into objects. A veterinarian will be best able to examine the pup's eyes for this condition with an examine the pup's eyes for this condition with an ophthalmoscope at 12 to 16 weeks of age, when the ophthalmoscope at 12 to 16 weeks of age, when the retina is matureretina is mature

GlaucomaGlaucoma is a leading cause of blindness in dogs. It is the is a leading cause of blindness in dogs. It is the result of increased fluid pressure within the eye (elevated result of increased fluid pressure within the eye (elevated intraocular pressure or IOP). If the pressure can not be intraocular pressure or IOP). If the pressure can not be reduced, there will be permanent damage to the retina and reduced, there will be permanent damage to the retina and optic nerve resulting in visual impairment. Complete optic nerve resulting in visual impairment. Complete blindness can occur within 24 hours if the IOP is extremely blindness can occur within 24 hours if the IOP is extremely elevated or can occur slowly over weeks or months if the elevated or can occur slowly over weeks or months if the elevation is mild. Glaucoma is usually very painful. It is elevation is mild. Glaucoma is usually very painful. It is considered a medical emergency Unfortunately it is not considered a medical emergency Unfortunately it is not usually apparent until dogs reach 3 year of age .usually apparent until dogs reach 3 year of age .

Eye DisordersEye Disorders Progressive retinal atrophyProgressive retinal atrophy: : deterioration of the retinal cells causes deterioration of the retinal cells causes

blindness. blindness. Generalized PRA - early onset:Generalized PRA - early onset: The first sign is generally failing The first sign is generally failing

night vision, as early as 6 weeks of age, and this progresses to night vision, as early as 6 weeks of age, and this progresses to complete loss of vision by about 1 - 2 years of age. Collies may retain complete loss of vision by about 1 - 2 years of age. Collies may retain some vision until the age of 2 - 3 years. In miniature schnauzers, poor some vision until the age of 2 - 3 years. In miniature schnauzers, poor night vision usually develops later (6 months to a year) and there is night vision usually develops later (6 months to a year) and there is advanced loss of vision by 3 to 4 years. Affected Alaskan malamutes advanced loss of vision by 3 to 4 years. Affected Alaskan malamutes are day-blind (hemeralopia) at 8 to 10 weeks of age; night vision is are day-blind (hemeralopia) at 8 to 10 weeks of age; night vision is never affected.never affected.

Generalized PRA (progressive rod-cone degeneration) - late Generalized PRA (progressive rod-cone degeneration) - late onset:onset: Generally night blindness is noticed between 2 and 5 years of Generally night blindness is noticed between 2 and 5 years of age (depending on the breed) progressing to total blindness within a age (depending on the breed) progressing to total blindness within a year or so. Peripheral vision is lost first.year or so. Peripheral vision is lost first.

Central PRA (CPRA) - retinal pigment epithelial dystrophy Central PRA (CPRA) - retinal pigment epithelial dystrophy (RPED): (RPED): Loss of vision occurs much more slowly than in generalized Loss of vision occurs much more slowly than in generalized PRA, without initial night blindness. Affected dogs may not lose vision PRA, without initial night blindness. Affected dogs may not lose vision completely. Because the changes are in the centre of the retina, completely. Because the changes are in the centre of the retina, affected dogs initially have trouble locating still objects in bright light. affected dogs initially have trouble locating still objects in bright light.

Nervous System DisordersNervous System Disorders HydrocephalusHydrocephalus: : an abnormal build-up of cerebrospinal fluid (CSF) in an abnormal build-up of cerebrospinal fluid (CSF) in

cavities in the brain (the ventricles). This results in increased pressure on cavities in the brain (the ventricles). This results in increased pressure on the brain. Puppies with severe hydrocephalus often die at a very early the brain. Puppies with severe hydrocephalus often die at a very early age due to pressure from the increased fluid in the brain. In other less age due to pressure from the increased fluid in the brain. In other less severely affected pups, the signs gradually become apparent over the first severely affected pups, the signs gradually become apparent over the first few months of life, and in some mild cases the condition is only diagnosed few months of life, and in some mild cases the condition is only diagnosed later in life. later in life. The types of signs seen with this condition include lack of thriftiness The types of signs seen with this condition include lack of thriftiness (smaller than littermates, slow to grow), a domed skull (which gradually (smaller than littermates, slow to grow), a domed skull (which gradually becomes more pronounced), abnormal movement behaviour (e.g., becomes more pronounced), abnormal movement behaviour (e.g., restlessness, aimless walking), problems with vision, and seizures. These restlessness, aimless walking), problems with vision, and seizures. These pups are very slow to learn - it may be extremely difficult to housetrain pups are very slow to learn - it may be extremely difficult to housetrain them for example, or they may lose their housetraining.them for example, or they may lose their housetraining.

Generally the signs gradually worsen, although by 2 years of age they may Generally the signs gradually worsen, although by 2 years of age they may stabilize. To minimize brain damage, the condition must be recognized and stabilize. To minimize brain damage, the condition must be recognized and appropriate treatment begun early. However, affected animals will likely appropriate treatment begun early. However, affected animals will likely always be slow and have a limited ability to learn.always be slow and have a limited ability to learn.

Nervous System DisordersNervous System Disorders Shaker dog diseaseShaker dog disease : : This disorder usually develops This disorder usually develops

suddenly in young adult dogs (6 months to 3 years of age). suddenly in young adult dogs (6 months to 3 years of age). The signs become progressively worse over 1 to 3 days and The signs become progressively worse over 1 to 3 days and then remain the same until treatment is begun. There is an then remain the same until treatment is begun. There is an all-over tremor that can range from mild to so severe that all-over tremor that can range from mild to so severe that the dog may have difficulty walking. This is called an the dog may have difficulty walking. This is called an intention tremor, meaning that it is worse when the animal intention tremor, meaning that it is worse when the animal is excited or tries to perform a specific action (such as eat, is excited or tries to perform a specific action (such as eat, walk towards an object, etc). The tremor decreases or walk towards an object, etc). The tremor decreases or disappears when the dog is relaxed or at rest. Commonly disappears when the dog is relaxed or at rest. Commonly there are rapid, random eye movements as well. The there are rapid, random eye movements as well. The condition is not painful and your dog's personality is condition is not painful and your dog's personality is unaffected. Treatment is generally effective; some dogs unaffected. Treatment is generally effective; some dogs require medication for life to control the tremorsrequire medication for life to control the tremors

Liver Disorders Liver Disorders Portosystemic shuntPortosystemic shunt: : Portosystemic shunt (PSS) is Portosystemic shunt (PSS) is

a birth defect of the circulation in the liver. Most a birth defect of the circulation in the liver. Most animals with congenital portosystemic shunts animals with congenital portosystemic shunts show symptoms before 6 months of age. When show symptoms before 6 months of age. When symptoms are subtle, however, the condition may symptoms are subtle, however, the condition may not be diagnosed until much later. The most not be diagnosed until much later. The most definitive way to deal with PSS is surgerydefinitive way to deal with PSS is surgery

Cornel University is doing a study on this defect. Cornel University is doing a study on this defect. The Maltese is one of the breeds being studiedThe Maltese is one of the breeds being studied

Reproductive Disorders Reproductive Disorders

CryptorchidismCryptorchidism: : Cryptorchidism means that one Cryptorchidism means that one or both of a dog's testicles have not descended or both of a dog's testicles have not descended into the scrotuminto the scrotum

Skin Disorders Skin Disorders sebaceous adenitissebaceous adenitis This is a perplexing condition in which the This is a perplexing condition in which the

sebaceous glands in the skin become inflamed for unknown sebaceous glands in the skin become inflamed for unknown reasons, and are eventually destroyed. These glands normally reasons, and are eventually destroyed. These glands normally produce sebum, a fatty secretion that helps prevent drying of the produce sebum, a fatty secretion that helps prevent drying of the skin.skin.This disorder requires long term management, which can be This disorder requires long term management, which can be frustrating for both owners and veterinarians because the frustrating for both owners and veterinarians because the response to treatment is highly variable. There may be periods of response to treatment is highly variable. There may be periods of spontaneous improvement or worsening of the condition, spontaneous improvement or worsening of the condition, independent of treatment.independent of treatment.Your veterinarian will likely try a combination of approaches, to Your veterinarian will likely try a combination of approaches, to determine with you what will be most effective for your dog. Most determine with you what will be most effective for your dog. Most important is the regular use of anti-seborrheic shampoos to important is the regular use of anti-seborrheic shampoos to remove scales and dead hair, together with fatty acid dietary remove scales and dead hair, together with fatty acid dietary supplements. This may be all that is required in mildly affected supplements. This may be all that is required in mildly affected dogs. Additional treatments include spraying the dog with a dogs. Additional treatments include spraying the dog with a mixture of propylene glycol and water to help restore lubricants to mixture of propylene glycol and water to help restore lubricants to the skin and the use of oral essential fatty acidsthe skin and the use of oral essential fatty acids

Nervous System Disorders Nervous System Disorders Deafness Deafness Pups lose their hearing a few to several weeks Pups lose their hearing a few to several weeks

after birth. Signs of bilateral deafness may include after birth. Signs of bilateral deafness may include aggressive play because the deaf pup does not hear cries aggressive play because the deaf pup does not hear cries of pain from littermates, and having to be jostled to of pain from littermates, and having to be jostled to waken. Unilateral deafness is much harder to spot.waken. Unilateral deafness is much harder to spot.

If your dog is deaf in only 1 ear, you will likely not even be If your dog is deaf in only 1 ear, you will likely not even be aware of it. In training sessions, you may notice that your aware of it. In training sessions, you may notice that your dog responds better to hand signals than verbal cues.dog responds better to hand signals than verbal cues.One-sided deafness is generally not a problem. However it One-sided deafness is generally not a problem. However it is much more difficult for bilaterally deaf dogs to lead a is much more difficult for bilaterally deaf dogs to lead a normal lifenormal life

Breeding stock should be tested by the BAER test before Breeding stock should be tested by the BAER test before being used for breeding, and pups should be tested before being used for breeding, and pups should be tested before being sold. Hearing loss, if present, is complete - that is being sold. Hearing loss, if present, is complete - that is the dog either has normal hearing, or is totally deaf in 1 or the dog either has normal hearing, or is totally deaf in 1 or both ears.both ears.

Hypoglycemia Low Blood Sugar Hypoglycemia Low Blood Sugar Seen in puppies 6 to 9 weeks Seen in puppies 6 to 9 weeks Can be fatal . Often occurs without warning. Can be fatal . Often occurs without warning. Causes : Stress, missing a meal, chilling, too much play and Causes : Stress, missing a meal, chilling, too much play and

upset stomach.upset stomach. Typical signs: listlessness depression, staggering gate, Typical signs: listlessness depression, staggering gate,

muscle weakness, and tremors especially in the face muscle weakness, and tremors especially in the face Severe sugar drop seizures develop, or puppy become Severe sugar drop seizures develop, or puppy become

stuperous and goes into a coma and without help dies.stuperous and goes into a coma and without help dies. Sometimes a puppy appears fine and goes into a coma Sometimes a puppy appears fine and goes into a coma Prolonged or repeated attacks can cause brain damage Prolonged or repeated attacks can cause brain damage A Veterinarian can rule out other cause such as liver shunt, A Veterinarian can rule out other cause such as liver shunt,

infections, or an enzyme or hormone deficiencyinfections, or an enzyme or hormone deficiency Although not a genetic problem this is mostly seen in young Although not a genetic problem this is mostly seen in young

puppies of toy breeds and is life threatening. puppies of toy breeds and is life threatening.

In ConclusionIn Conclusion Maltese list 11 health concerns Disorders relatively

common in this breed :Patent duchtus arteriosus . PDA

Note above disorder(s) is very common in this breed. Do not take lightly the other disorders. Some are very serious .

Information for this presentation as a public service provided by: www.delayrekennel.com with information provided by :

A joint initiative of the Sir James Dunn Animal Welfare Centre at the Atlantic Veterinary College, University of Prince Edward Island, and the Canadian Veterinary Medical Association..

Permission is granted to reprint pages from the database, provided that credit is given as follows: Crook A et al. 2011. Canine Inherited Disorders Database