Inherited disorders of the urinary and reproductive systems

Cryptorchidism, retained testicle

roblib — Sun, 02 May 2010 01:42:47 +0000

What is ... ?:

During development before birth, the testicles migrate from the abdomen into the scrotum. Normally this is complete by 10 days of age. Cryptorchidism means that one or both of a dog's testicles have not descended into the scrotum. If this does not happen by 8 weeks, the dog is generally diagnosed as cryptorchid, although the testicles may still descend up to 4 months or so.

How is ... inherited?:

Although the condition is of course seen only in male dogs, both males and females can carry the gene for cryptorchidism. Heterozygous males and females, and homozygous females, will be physically normal, but can pass the gene on to their offspring. Homozygous males are cryptorchid. Thus cryptorchidism is thought to be a sex-limited autosomal recessive trait

What breeds are affected by ... ?:

What does ... mean to your dog & you?:

Dogs that are cryptorchid have a much increased risk of testicular cancer (approximately 10 times). Castration will of course eliminate this risk. Dogs with cryptorchidism can not be shown.

How is ... diagnosed?:

Your veterinarian will diagnose this condition when s/he examines your dog at the time of vaccination. Most affected dogs have 1 testicle that is not descended.

How is ... treated?:

The only treatment for this condition is removal of both testicles (neutering or castration). Dogs with cryptorchidism should be castrated for 2 reasons: if the testicles are not removed, there is an increased risk of testicular cancer, and if your dog is bred, the trait will be passed on to future generations.

Breeding advice:

Affected dogs and their parents (who carry the gene) should be not be bred.

Resources:

Wheeler R. Cryptorchidism. In: Côté E, ed. Clinical Veterinary Advisor Dogs and Cats. Missouri: Mosby Elsevier, 2007:261.

Sargan DR. Cryptorchidism. In IDID - Inherited diseases in dogs:web-based information for canine inherited disease genetics.

Disorders of sexual development - sexual reversal

roblib — Sun, 02 May 2010 01:45:03 +0000

What is ... ?:

At fertilization, the sex chromosomes are established as XX (the animal will be female) or XY (male). During development of the embryo, ovaries develop if the chromosomes are XX, and testicles if XY. An abnormality can occur in chromosome differentiation (to produce XXY, XXX, XO). This is rare in dogs and is not thought to be inherited. Gonadal intersex refers to developmental abnormalities in the gonads (ovaries and testicles) despite a normal set of sex chromosomes. In some cases (pseudohermaphrodites), the sex chromosomes in these dogs match the sex of the gonads, but the genitals are abnormal. This is only seen (rarely) in females, and is generally due to excess exposure to male sex hormones during development - ie. environmental factors rather than an inherited condition.

Sexual reversal describes the condition where the chromosomal and gonadal sex differ. Only XX sexual reversal has been seen in dogs. The dog may be a XX true hermaphrodite (female chromosomes in a dog with both ovaries and testicles), or XX male (female chromosomes, with testicles).

How is ... inherited?:

XX sex reversal is an autosomal recessive trait in the breeds listed below. It has been reported sporadically in several other breeds where the inheritance is not understood.

What breeds are affected by ... ?:

What does ... mean to your dog & you?:

Affected animals are infertile (so that your apparently female dog will not come into heat), and may have chronic irritation in the genital area, which may look abnormal to you.

How is ... diagnosed?:

Your veterinarian will typically suspect one of these conditions when s/he notices an abnormality such as clitoral enlargement or an abnormal penis during physical examinataion of your dog, or if a breeding dog is being examined for infertility. To diagnose the specific condition requires your veterinarian to evaluate both internal (generally at the time of spay) and external sex organs, and send away a blood or other cell sample from your dog for karyotyping, which identifies the chromosomes.

How is ... treated?:

Affected animals should be neutered.

For the veterinarian:

Dogs with XX sexual reversal may be XX true hermaphrodites or XX males. These dogs can appear in the same family, and result from the same genetic defect. XX true hermaphrodites have both ovarian and testicular tissue. The degree of masculinization of internal and external genitalia depends on the proportion of testicular tissue in the gonads. XX males have a uterus, bilateral (usually undescended) testes, and a prepuce that is located abnormally.

Breeding advice:

Affected animals, their parents (carriers) and siblings (potential carriers) should not be used for breeding.

Resources:

Meyers-Wallen V. Inherited disorders of the reproductive tract in dogs and cats. In: Bonagura JD, Twedt DC, eds. Kirk's Current Veterinary Therapy XIV. Missouri: Saunders Elsevier, 2009:1034-1039.

Mickelsen WD, Memon MA. 1995. Inherited and congenital disorders of the male and female reproductive systems. In E.J. Ettinger and E.C. Feldman (eds.) Textbook of Veterinary Internal Medicine, p. 1686-1690. W.B. Saunders Co., Toronto.

Sargan DR.Sexual reversal. In IDID - Inherited diseases in dogs:web-based information for canine inherited disease genetics. 2002-2011.

Familial kidney disease

roblib — Sun, 02 May 2010 01:55:45 +0000

What is ... ?:

Several breeds of dogs are known to be affected by a wide range of kidney diseases that are proven or suspected to be inherited. In many of these disorders, the kidneys are apparently normal at birth but begin to deteriorate early in life (less than 1 year of age). While the underlying problem in the kidneys varies between breeds, the end result is the same - kidney failure for the dog, generally by 5 years of age, although the severity and rate of progression vary between breeds and between individual dogs.

For many of these disorders, the mode of inheritance is not known. The term "hereditary" is used when the inheritance is known, and "familial" when the mode of inheritance is not known but the disorder occurs more commonly in related dogs than would be expected by chance. Where the actual defect in the kidney has been identified, a more specific name (given below) may be used. More than one name may be used for a particular disorder (see Related Terms below).

Breed	Disorder	Inheritance (if known)	(for veterinarian)
Bernese mountain dog	familial glomerulonephritis	thought to be autosomal recessive	membranoproliferative glomerulonephritis; immune-mediated
Bull terrier	hereditary nephritis	autosomal dominant	defect is in the structure of the glomerular basement membrane
Doberman pinscher	familial glomerulonephropathy	unknown	irregularities in glomerular basement membrane
English cocker spaniel	hereditary nephritis	autosomal recessive	abnormality in glomerular basement membrane
Golden retriever	renal dysplasia	thought to be autosomal recessive	abnormal differentiation of kidneys
Lhasa apso, shih tzu	renal dysplasia	thought to be autosomal recessive	abnormal differentiation of kidney tissue
Norwegian elkhound	familial nephropathy	unknown	tubulo-interstitial nephropathy
Pembroke Welsh corgi	renal telangiectasia	unknown	multiple dilated renal blood vessels
Samoyed	hereditary nephritis	X-linked dominant	abnormality in glomerular basement membrane
Schnauzer, miniature	juvenile nephropathy	unknown	glomerular and tubular lesions
Shar pei, Chinese	renal amyloidosis	unknown, possibly autosomal recessive	amyloid deposition most disruptive in kidneys; other organs (spleen, liver, pancreas) can be affected but with minimal clinical signs; may also have intermittent fever and joint swelling
Rottweiler	renal dysplasia	unknown	abnormal differentiation of kidney tissue
Soft-coated wheaten terrier	renal dysplasia	thought to be autosomal recessive	abnormal differentiation of kidney tissue
Soft-coated wheaten terrier	see protein-losing enteropathy and nephropathy	unknown, familial	onset 6 years plus; chronic glomerulonephritis/glomerulosclerosis

Familial kidney disease has also been reported in the English foxhound (renal amyloidosis), Belgian shepherd (Malinois) (glomerulocystic disease), bull mastiff (glomerulonephropathy), and Rhodesian ridgeback, border terrier and Dutch kooiker (all renal dysplasia).

What breeds are affected by ... ?:

What does ... mean to your dog & you?:

The signs of kidney failure are the same in young animals as in older dogs. One of the earliest signs you may notice is that your dog drinks more and urinates more. (Sometimes in young pups, owners may not recognize excessive urination as such, but think it is due to the dog being slow to housetrain.) As more and more kidney function is lost, other signs develop including poor appetite, loss of weight, lethargy, vomiting, and pale gums due to anemia. Although the progression may be slowed by treatment, kidney failure is ultimately fatal.

For most of these disorders, dogs show signs of kidney dysfunction before 1 year of age, and their kidneys fail before 5 years of age. In pups affected at a very young age (less than 5 or 6 months), growth may be noticeably stunted. Polycystic kidney disease in bull terriers is an exception. Affected animals often show no signs until 2 years of age or more, and may not develop kidney failure until 8 years. In Doberman pinschers and Norwegian elkhounds, signs of kidney failure may also appear later in life (6 years of age). In the samoyed, because inheritance is sex-linked, males are more severely affected. Male pups with hereditary glomerulonephropathy usually show signs by 2 to 3 months of age, and kidney function deteriorates rapidly, resulting in death by an early age (approximately 1 year). Although affected females still show some kidney dysfunction, it is less severe and does not progress to kidney failure. Even if only mildly affected, they are carriers of the disorder and should not be bred. In Chinese shar-pei dogs affected with amyloidosis, amyloid (a type of protein) is deposited in the kidneys and other organs. Most of the time, the clinical signs you see relate to disruption of kidney function which eventually (by about 3 to 5 years of age) leads to kidney failure. Affected dogs may have intermittent fever and swelling and pain in their joints, especially the hocks. Pembroke Welsh corgis with renal telangiectasia have episodes of blood in the urine as adults.

How is ... diagnosed?:

The signs described above can have several causes, including other inherited disorders such as a heart or liver defect. Your veterinarian will do blood and urine tests that will point to your dog's kidneys as the cause of the problem.

FOR THE VETERINARIAN
Typical signs of CRF include azotemia, hyperphosphatemia, isosthenuria, and nonregenerative anemia. Calcium concentrations are variable. Persistent proteinuria is highly suggestive of hereditary nephritis, even before any clinical signs are evident. Proteinuria is not a consistent sign in renal dysplasia.

In suspect bull terriers, repeated protein/creatinine ratios 0.3 provide supportive evidence for hereditary nephritis in dogs that are older than 2 years of age, but who show no overt signs of renal failure. This provides important information in decisions about breeding. Male samoyeds with hereditary glomerulonephropathy develop proteinuria, glucosuria and isosthenuria by 2 to 3 months of age, and azotemia and overt renal failure by 6 to 9 months. Affected females (carriers) develop proteinuria at a young age but may never progress to renal failure. In cocker spaniels with familial nephropathy, proteinuria is usually present by 4 to 6 months of age and is persistent and marked. This is followed by decreased growth, and the development of isosthenuria and azotemia.

There are 2 different familial renal syndromes in the soft-coated wheaten terrier- renal dysplasia (onset usually before 2 years of age) and protein-losing enteropathy and nephropathy (onset 2 to 11 years of age). In Chinese shar pei dogs with renal amyloidosis, proteinuria is usually marked, although it may be mild or absent in dogs with renal medullary, but not glomerular, amyloidosis.

VetGen has DNA testing available for kidney disease in some breeds.

How is ... treated?:

There is no cure, but there are ways to slow the progression of kidney disease, which your veterinarian will discuss with you. These include making sure your dog always has access to fresh drinking water, feeding a special (high quality, low-protein) diet, and the use of some medications which help to support kidney function. Your veterinarian will help you to recognize the signs that your dog's kidneys have deteriorated to the point where euthanasia becomes the best option.

FOR THE VETERINARIAN
Patients should be managed (including regular monitoring)as for other animals with chronic renal failure. The goals are to maintain normal hydration and electrolytes, delay the progression of renal failure and its complications, address signs of uremia (eg.vomiting), and minimize proteinuria.

Breeding advice:

Affected animals should not be bred, and neither should their parents. Any related animal being considered for breeding should be screened for protein in the urine, which is an early sign of kidney disease. All bull terriers being considered for breeding should be screened by measuring protein/creatinine ratios ( a simple test requiring a blood and a urine sample). Ratios greater than 0.3 on 2 occasions more than a month apart, indicate potential hereditary nephritis. Kidney function in these dogs should be monitored, and they should not be used for breeding.

FOR MORE INFORMATION ABOUT THIS DISORDER, PLEASE SEE YOUR VETERINARIAN.

Resources:

Dalby AM. Glomerulonephritis. In: Côté E, ed. Clinical Veterinary Advisor Dogs and Cats. Missouri: Mosby Elsevier, 2007:442-444.
DiBartola, S. 1998. Renal amyloidosis. ACVIM-Proceedings of the 16th Annual Veterinary Medical Forum. p. 23-24.
Gleadhill, A. 1997. Juvenile nephropathies in dogs and cats. In Practice. Vol 19(5):270-277.
Mordecai A, Sellon RK. In: Côté E, ed. Clinical Veterinary Advisor Dogs and Cats. Missouri: Mosby Elsevier, 2007:953-954.
Sargan DR. (Search for renal disease by name, as above). In IDID - Inherited diseases in dogs:web-based information for canine inherited disease genetics. 2002-2011.

Fanconi syndrome

roblib — Sun, 02 May 2010 02:41:11 +0000

What is ... ?:

In the normal kidney, there is selective reabsorption of water, sugars, minerals, and amino acids so that these substances are not lost excessively in the urine. In a dog affected with Fanconi syndrome, there is a defect in the tubules of the kidney where this resorption occurs. Loss of these substances (that would normally be conserved) leads to various serious problems for the animal such as electrolyte imbalances, dehydration and weight loss.

This disease can also be acquired in any breed (as opposed to inherited) as a result of various toxins (e.g., heavy metals).

How is ... inherited?:

This is a significant disorder in the Basenji breed, affecting upwards of 10% of dogs. The mode of inheritance is presumed to be autosomal recessive. This disorder has also been seen in other breeds (as below) - mode of inheritance unknown.

What breeds are affected by ... ?:

What does ... mean to your dog & you?:

Dogs that are affected with this disorder usually show signs anywhere from 3 to 7 years of age. The earliest signs are excessive drinking and urination, because the kidneys are unable to conserve water. Because of the loss of nutrients and electrolytes in the urine, your dog may experience weight loss and muscle weakness. The condition may worsen slowly over several years, or may progress rapidly to kidney failure with signs such as poor appetite, extreme loss of weight, lethargy, vomiting, and pale gums due to anemia. Dogs with Fanconi syndrome are prone to urinary tract infections due to the sugar in the urine.

How is ... diagnosed?:

The signs described above can have several causes. Your veterinarian will do blood and urine tests that will point to your dog's kidneys as the cause of the problem.

FOR THE VETERINARIAN
Laboratory findings include low urine specific gravity, glucosuria with normoglycemia (diagnostic in a Basenji), phosphaturia, and aminoaciduria. The defective urine concentrating ability represents a form of nephrogenic diabetes insipidus; isosthenuria or hyposthenuria may precede glucosuria. There may be mild proteinuria.

As the disease progresses, dogs will develop azotemia, hypophosphatemia, variable metabolic acidosis (hyperchloremic), and hypokalemia (which may contribute to the muscle weakness sometimes seen). Unlike other hereditary kidney diseases, the primary abnormality is functional with little apparent structural change. The kidneys are generally grossly normal, and lesions with light microscopy are variable and non-specific.

Primary renal glucosuria is an uncommon disorder in which there is glucosuria with normal blood glucose concentrations and otherwise normal kidney function. It can be differentiated from Fanconi syndrome based on the absence of other solutes (amino acids, electrolytes) in the urine. It has been found in the Norwegian elkhound and may cause urinary tract infections.

How is ... treated?:

There is no cure, but there are ways to slow the progression of kidney disease, which your veterinarian will discuss with you. These include making sure your dog always has access to fresh drinking water and, depending on the stage of the disease, feeding a special (high quality, low-protein) diet and the use of some medications which help to support kidney function. Regular monitoring of kidney function is important.

For the veterinarian: Management of this disease includes regular monitoring; vitamin, mineral and amino acid replacement; control of metabolic acidosis with sodium bicarbonate; and medical management of uremia of chronic renal failure as necessary. Potassium citrate therapy provides both alkalinization and potassium supplementation.

Breeding advice:

Fanconi syndrome is an important problem in the Basenji breed, affecting 10% or more of dogs. Affected dogs should not be bred and, because the mode of inheritance is unconfirmed, it is safest to avoid breeding either parent or any siblings. One problem for breeders is that the condition may not become evident until 6 or 7 years of age. There is a linked marker DNA test available for Basenjis through the OFA that gives results of probable normal, probable carrier, probable affected, and indecisive.
FOR MORE INFORMATION ABOUT THIS DISORDER, PLEASE SEE YOUR VETERINARIAN.

Resources:

Langston C. Fanconi syndrome. In: Côté E, ed. Clinical Veterinary Advisor Dogs and Cats. Missouri: Mosby Elsevier, 2007:375-376.

Sargan DR. Fanconi syndrome. In IDID - Inherited diseases in dogs:web-based information for canine inherited disease genetics. 2002-2011.

Basenji Health Issues information

Renal cystadenocarcinoma and nodular dermatofibrosis

roblib — Sun, 02 May 2010 02:49:14 +0000

What is ... ?:

This is a condition in German shepherd dogs in which lumps (nodules) form on the skin, generally on the head and legs. In most affected dogs, the condition is associated with cancer of the kidneys (renal cystadenocarcinoma), or of the uterus in females that have not been spayed.

How is ... inherited?:

The mode of inheritance is autosomal dominant with complete penetrance.

What breeds are affected by ... ?:

German shepherd

What does ... mean to your dog & you?:

Skin lesions are generally first seen in dogs over 5 years of age. You will notice small, firm, usually painless bumps or nodules on your dog's limbs and/or head. Over time these will increase in size and number. The lesions themselves cause few problems, although they may become ulcerated and painful as they grow larger. Most important however, is the fact that they are usually associated with cancer of the kidneys (or of the uterus in unspayed females). The signs that you may see if your dog has kidney disease include increased drinking and urination, loss of appetite and weight loss, a swollen abdomen (due to fluid retention or tumour size), depression, and vomiting.

How is ... diagnosed?:

Your veterinarian will surgically remove one of the skin nodules (a simple procedure done with local anesthetic) for examination by a veterinary pathologist. The biopsy will show changes characteristic of this condition. Your veterinarian will also look for signs of kidney disease. S/he may be able to feel that the kidneys are enlarged or you may have already noticed some of the typical clinical signs listed above. Your veterinarian will also take blood and urine samples to look for indications of kidney disease, and likely also recommend radiography or an ultrasound.

How is ... treated?:

There is no specific treatment for this condition. The nodules can be surgically removed if they are large or painful, and generally do not grow back if excised fully (although new ones will continue to appear). Unspayed females should be spayed, to remove the potential of cancer in the uterus and also because these dogs definitely should not be bred. Your veterinarian will carefully monitor your dog's kidney function - both kidneys are usually affected. Your veterinarian will discuss with you supportive care for your dog as kidney disease progresses, such as a special diet and fluid therapy when needed.

Breeding advice:

Affected animals should not be bred, and siblings and parents should be carefully examined for nodules. Because nodular dermatofibrosis has an autosomal dominant mode of inheritance, all dogs with the defective gene will develop the condition. Theoretically it should be possible to eradicate this problem. However because signs do not appear until the dogs are over 5 years of age, it is quite possible that they have already been used for breeding. The best course is to discontinue breeding lines in which there are affected dogs. Although there are no screening tests, computed tomography (a radiographic technique) is the best way to detect early cases.

FOR MORE INFORMATION ABOUT THIS DISORDER, PLEASE SEE YOUR VETERINARIAN.

Resources:

Moe L, Lium B. Hereditary multifocal renal cystadenocarcinomas and nodular dermatofibrosis in 51 German shepherd dogs. Journal of Small Animal Practice. 1997 38:498-505.

Pressler B. Cancer and the kidney. In: Bonagura JD, Twedt DC, eds. Kirk's Current Veterinary Therapy XIV. Missouri: Saunders Elsevier, 2009:928.

Sargan DR. Renal cystadenocarcinoma and.... In IDID - Inherited diseases in dogs:web-based information for canine inherited disease genetics.

Urolithiasis (stones)

roblib — Sun, 02 May 2010 02:52:58 +0000

What is ... ?:

Urolithiasis is a condition in which crystals in the urine combine to form stones, also called calculi or uroliths. These can be found anywhere in the urinary tract, where they cause irritation and secondary infection. Most end up in the bladder or in the urethra, where they may cause obstruction, which is a medical emergency. Several different types of uroliths have been identified, with struvite stones (magnesium ammonium phosphate) the most common. Dogs of any breed can develop uroliths, but a genetic predisposition to producing crystals in some breeds makes the development of stones more likely.

Dalmatians have a defect in the pathway (purine metabolism) that normally leads to the breakdown of urates, a by-product of protein digestion. This results in increased urate excretion in the urine, and this predisposes them to the formation of urate crystals and eventually, stones. In some other breeds, an inherited defect in a different pathway causes excessive urinary excretion of the amino acid cystine, resulting in cystine crystals and potentially stones in the urine.

Type of crystal/stone	Breeds affected	Inheritance	Treatment	Prevention
Struvite (triple phosphate, MAP)	Bichon frise, Dandie Dinmont terrier, miniature poodle, miniature schnauzer, shih tzu, Yorkshire terrier, seen in many other breeds as well	This is the most common type of stone seen, but little is known about inheritance.	Dissolve medically or remove surgically; treat UTI*	Feed special diet; acidify urine
Urate/biurate	Dalmatian Black Russian terrier, dachshund, English bulldog, giant schnauzer, large Munsterlander, mastiff, Parson (Jack) Russell terrier, South African Boerboel, Weimaraner	Autosomal recessive	Dissolve medically or remove surgically	Special diet (reduced purine) and, if necessary, allopurinol; alkalinize urine
Calcium oxalate	Bichon frise, Dandie Dinmont terrier, Lhasa apso, miniature poodle, miniature schnauzer, Shih tzu, Yorkshire terrier	Little is known	Remove surgically.	Special diet; alkalinize urine.
Cystine	Dachshund, English bulldog, Newfoundland, Irish terrier, mastiff	Thought to be autosomal recessive		Special diet; alkalinize the urine.
Xanthine	Cavalier King Charles spaniel, dachshund	Thought to be autosomal recessive

* UTI - urinary tract infection

For many breeds and many disorders, the studies to determine the mode of inheritance or the frequency in the breed have not been carried out, or are inconclusive. We have listed breeds for which there is a consensus among those investigating in this field and among veterinary practitioners, that the condition is significant in this breed.

How is ... inherited?:

The trait for hyperuricosuria (elevated uric acid in the urine, leading to urate stones) is autosomal recessive. It is present in all Dalmatians, although not all will develop urolithiasis. A DNA test is available (see here) to test for this mutation in the many breeds affected. There is also a test available for the trait causing high cystine in the urine (cystinuria) of Newfoundland dogs.

What does ... mean to your dog & you?:

The changes in the urine are generally present from birth. However it usually takes some time for crystals to form and combine into stones that cause problems, most often between 3 and 6 years of age. The signs you will see in your dog depend on where in the urinary tract the stones end up. They collect most commonly in the bladder, in which case you may see blood in the urine, difficulty and pain in urinating, and small frequent amounts of urine.

Urinary tract obstruction is a serious condition that occurs when a stone completely blocks the urethra and thus blocks the outflow of urine (more common in male dogs, who have a smaller urethra). Signs include straining to urinate, vomiting and loss of appetite, weakness and lethargy (due to toxins building up in the body).

How is ... diagnosed?:

If your dog is showing the physical signs described above, your veterinarian will do an analysis of his/her urine (urinalysis) to look for crystals and also for a bacterial infection, which is commonly seen with this condition. Many stones can be seen with x-rays; some (especially urate uroliths) will only show up with contrast radiography. Ultrasound can generally detect stones of all types.
FOR THE VETERINARIAN
Types of uroliths vary in radiodensity. Struvite and calcium oxalate uroliths are usually obvious on radiography; urate uroliths may be radiolucent and therefore require contrast radiography or ultrasonography.

How is ... treated?:

A combination approach is usually needed. Stones are often small and numerous. Larger ones may be removed surgically - this is necessary if the stone is blocking the ureter or a kidney, if your dog is in pain, or if the stones do not dissolve after a period of medical management. The medical approach is to dissolve the stones gradually by changing the pH of the urine, ie. making it more or less acidic (depending on the type of stone) through medication and changes in diet.Special diets also result in a larger volume of more dilute urine, making it easier for a dog to pass the stones. Your veterinarian will monitor your dog's progress through periodic radiographs and analysis of the urine over the period of time the stones are dissolving (which can take some months). Some types of stones are more amenable to dissolution than others.

In all cases of urolithiasis, in addition to paying careful attention to your dog's diet, you can help to reduce the formation of stones by providing lots of fresh water and regular opportunities to urinate, so that urine doesn't accumulate in the bladder allowing time for stones to form. You can increase your dog's water consumption by feeding a canned diet with a high water content, or mixing dry food with water.

Bacterial urinary tract infections are common with urolithiasis, and should be treated promptly.

Breeding advice:

Affected animals should not be bred, and it is preferable to avoid breeding their parents and siblings as well. Carriers for hyperuricosuria, and for cystinuria in the Newfoundland, can be identified through DNA testing (see links below).

FOR MORE INFORMATION ABOUT THIS DISORDER, PLEASE SEE YOUR VETERINARIAN.

Resources:

Faunt KK, Cohn LA. Urolithiasis (Oxalate, Struvite, Urate/Biurate, Other). In: Côté E, ed. Clinical Veterinary Advisor Dogs and Cats. Missouri: Mosby Elsevier, 2007:1125-1132.

Karmi N et al. Estimated frequency of the canine hyperuricosuria mutation in different dog breeds.J Vet Intern Med. 2010, 24:1337-1342.

Sargan DR. Urolithiasis. In IDID - Inherited diseases in dogs:web-based information for canine inherited disease genetics. 2002-2011.

Veterinary Genetics Laboratory - DNA test for hyperuricosuria

Optigen - DNA test for cystinuria in Newfoundland dog