Liver Shunt

Symptoms: Affected animals may exhibit poor growth, and coat conditions, especially when compared to their littermates.  Behavioral changes (such as head pressing pushing the head against a solid object) and balancing problems are common and may be subtle. Other signs are seizures, weakness, salivation, vomiting, and poor appetite. Other less common signs include drinking or urinating too much, and diarrhea.
There may also be an adverse response to sedation or anesthesia (especially diazepam), taking an exceeding amount of time to recover from drugs used. Other animals may show no signs until they are older, when they develop bladder and kidney problems. 
If symptoms are often temporary or increase dramatically after eating this is a strong supportive sign of a portosystemic shunt.

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Pancreatitis & Enzyme Deficiency

The pancreas has 2 functional parts. The "exocrine" is the part of the pancreas tissue that produces enzymes used to digest food, and the "endocrine" which secretes hormones such as insulin and glucagon.

It is important contact your vet for proper diagnosis of illness. When the pancreas becomes inflamed, the disorder is called pancreatitis. It is a disease process that is seen commonly in the dog.  There is no age, sex, or breed predisposition. 
Pancreatitis consist of two main forms; The mild sudden onset and the more acute, hemorrhagic form. Some dogs that recover from an acute episode may continue to have recurrent bouts, known as chronic, relapsing pancreatitis.  The associated inflammation allows digestive enzymes to spill into the abdominal cavity; this may result in secondary damage to surrounding organs, such as the liver, bile ducts, gall bladder, and intestines. 

An unbalanced diet, medication, and reflux of bile acids and bacteria from the duodenum into the pancreas, can all contribute to pancreatitis, the cause is not known and cases need to be carefully assessed for any identifiable causes. Under normal conditions, digestive enzymes produced by the pancreas are activated when they reach the small intestines.  In pancreatitis, these enzymes are activated prematurely in the pancreas instead of in the small intestines.  This results in digestion of the pancreas itself. The disease is typically manifested by nausea, vomiting, fever, abdominal pain, and diarrhea.  If the attack is severe, acute shock, depression, and death may occur. 

If a significant number of cells that produce digestive enzymes are destroyed, a lack of proper food digestion may follow. If a significant number of cells that produce insulin are destroyed, diabetes mellitus can result.  In rare cases, adhesions between the abdominal organs may occur as a consequence of pancreatitis. 

Pancreatic enzyme deficiency or Exocrine Pancreatic Insufficiency (also called “Maldigestion”)
Enzymes break down  nutrients which are digested and then absorbed. Without adequate productive of these enzymes, we cannot digest our food. If we cannot digest the food, we cannot absorb the food. The pancreas gradually becomes shriveled and useless (atrophy). 

This condition is not congenital (present at birth) and may develop at any age (though usually shows up before age 4 years). About 70% of dogs with exocrine pancreatic insufficiency are German Shepherd dogs and 20% are Rough Collies.

Mode of inheritance: appears to be autosomal recessive and involves immune-mediated destruction of the pancreas.   

Breeding Advise: Affected dogs, and in German shepherds, their parents (considered carriers) and siblings (suspect carriers) should not be used for breeding.

Symptoms: Affected dogs progressively lose weight despite voracious appetites. Stools have an unusual odor, and these animals usually pass large amounts of semi-formed feces, or greasy diarrhea. Often owners complain of Coprophagy (Feces Ingestion). A dog might also develop a dry/dandruff coat and/or brittle and coarse hair from inability to absorb dietary fats.

Testing: A TLI blood test is available (The Serum Trypsin-like Immunoreactivity test). The test looks for a normal level of trypsin-like enzymes in the bloodstream. A dog  with enzyme deficiency (EPI) will have abnormally low levels. The dog must be fasted for the test to be accurate but only a single blood sample is needed to make the diagnosis. This test is often combined with serum folate and cyanocobalamin (Vitamin B12) testing since these can help determine how severe the defiency is and also help sort our other inflammatory bowel diseases that might be present.

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Thyroid (hyper or hypo)

Hyperparathyroidism - High thyroid levels.
Associated with cancer, It is unusual for dogs to have hyperthyroidism, which is more common in cats.

Hypothyroidism - Too low a level of thyroid hormone in the body.
There are two forms of hypothyroidism in dogs. In one, more common form, (autoimmune or lymphocytic thyroiditis) the immune system attacks the thyroid gland. In the second form, the gland seems to atrophy for other reasons.
The disorder may be acquired (most common) or congenital, and can be difficult to diagnose. Acquired hypoyhyroidism is genrally seen in middle aged (4-10 yrs) medium to large breed dogs. Congenital hypothyroidism is very rare, puppies will have stunted growth as well as many other abnormalities. Severely affected puppies most likely die before weaning..

Mode of inheritance: Is unknown

Breeding advise: Although inheritance of this disorder has not been determined, it is advisable not to breed affected dogs

Symptoms: Hyperparathyroidism HPT can cause loose teeth, brittle bones, and kidney damage.
With Hypothyroidism, symptoms can begin with loss or thinning of the fur, dull hair coat, excess shedding or scaling, weight gain,  lower energy levels,   increased susceptibility to infections and intolerance to cold. As the disease progresses, slow heart rate, lethargy,  infertility, and constipation. The accumulation of substances called mucopolysaccharides can cause the muscles of the face to droop giving the dog a facial expression that is sometimes called “tragic”.

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Hernia

A hernia which can be pushed back into the abdomen is called reducible. Hernias which are not reducible are called incarcerated. If the blood supply to an incarcerated hernia is pinched off the hernia becomes strangulated. A strangulated hernia is an emergency situation and must be brought to the immediate attention of your veterinarian.

An umbilical hernia is a swelling in the center of the abdomen, caused be a small opening in the muscle where the umbilical cord was attached, this results in malplacement of abdominal organs. In most cases umbilical hernias are small and reduce as the puppy grows. Generally, by the time the pup is six months old the umbilical hernia will shrink and disappear on its own. If the pup has a large hernia, or one that can be pushed into the abdomen with a finger, consult your veterinarian regarding possible surgical repair. 
Inguinal hernias are found in the groin area and can be located on both sides of the groin. They can occur in both male and female dogs, but are more common in females. As with umbilical hernias most inguinal hernias will shrink and disappear as the puppy grows, although you must keep an eye on the size of the hernia(s). 
Diaphragmatic hernias are the result of a tear in the diaphragm which allows abdominal organ portions to pass into the chest area. Most common occurrence is following an accident.

Mode of inheritance: Umbilical hernias are recessive, polygenic. 

Breeding Advise: Umbilical hernia - It is recommended that any dog with it should be spayed/neutered, however, the umbilical hernia can also be caused by the mother as she tries to clean up the cord area on her new pup.
Dogs affected by an inguinal hernia should not be bred..

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The way teeth align with each other is termed occlusion. Malocclusion refers to abnormal tooth alignment, a condition where the teeth do not meet in a proper scissors bite. Sometimes found in Arctic Wolfdogs, exhibiting a overshot or undershot jaw.
Undershot jaw - Abnormality of the skull where the upper jaw is too short for the rest of the head (when the lower teeth protrude in front of the upper jaw teeth).
Overshot jaw - Abnormality of the skull where the upper jaw is too long for the rest of the head. (The lower jaw shorter than the upper)
level bite - If the upper and lower incisor teeth meet each other edge to edge, the occlusion is an even or level bite.
Open bite - When the upper and lower incisors do not overlap or even meet each other when the mouth is closed..
Anterior crossbite - occurs when the canine and premolar teeth on both sides of the mouth occlude normally but one or more of the lower incisors are positioned in front of the upper incisors. Anterior crossbite is the most common malocclusion. If there is an anterior crossbite there must be a condition termed posterior crossbite.
Posterior crossbite - occurs when one or more of the premolar lower jaw teeth overlap the upper jaw teeth. This is a rare condition that occurs in the larger-nosed dog breeds.
A wry mouth - or bite occurs when one side of the jaw grows longer than the other.
Base narrow - canines occur when the lower canine teeth protrude inward and can damage the upper palate. Often this condition is due to retained baby teeth.

Mode of inheritance: Undershot/overshot jaw is a recessive trait. Anterior crossbite, is not considered genetic or hereditary. A wry mouth is considered hereditary.

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Cryptorchidism is a condition in which the testes fail to descend into the scrotum. The dog so afflicted is called a cryptorchid. If one testicle is retained, he is unilateral (one-sided), if both are affected, a bilateral cryporchid. Two conditions that can be verified only through extensive surgery are a monorchidism, which is the rare presence of only one testicle ANYWHERE in the body, and anorchids which are males with no testicles. 

The time it takes for the testes to migrate to the scrotum can vary from individual to individual, however, on the average, the testes are completely descended within 10 to 14 days following birth. Absence of one or both testes in the scrotum by 8 weeks of age warrants a diagnosis of cryptorchidism and it is supposed to be highly unlikely that testicles will descend if they can not be found outside the body wall by around four months of age. In only a minority of dogs, does descent occur as late as 6 months, and this variation is considered suspect of a developmental abnormality.  

Breeding advise: Sperm production will occur in the descended testis of unilateral cryptorchids. But because of the genetic basis, an increased risk for testicular cancer, and testicular torsion, generally bilateral castration (orchidectomy) is recommended.

Mode of inheritance: Cryptorchidism is inherited as a sex-limited autosomal recessive trait.

Testing: Palpation of the scrotum provides evidence of the presence or absence of two testes

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I recently had a visit with a high content Wolfdog who had a black spot on it's tongue. Having never seen this before, and always wanting to learn more, I decided to do some research into this and thought I would share it here (even though I wouldn't call it a disorder, so I added the "etc").
It seems this is something that appears in WD's as well as in pure's, and is generally thought of as similar to a beauty mark on a person. 

I wondered if this would be considered a fault in any of the dog breeds. Personally I would not prefer this in one of my animals for two reasons:

1. People believing that the black spot means the animal is a chow cross.

2. It can be visually distracting.

I wrote to a friend who has helped with my questions in the past, and was told:

1. They are not considered a fault in most show rings. Although I did find that the official U.K.C. Breed Standard for Jindo dogs states, "The tongue is large and deep pink without any spots". Also C.K.C Akita Breed Standard, "No black spots on tongue".

2. There are a couple of theories as to the cause...

• There are Germ cells (egg/sperm - reproductive cells) and Somatic cells (any other cell in the body). The most likely cause of this spot I was told, is a somatic mutation (permanent change or structural alteration in the DNA) of the recessive yellow gene - to black. Sometimes for the same reasons, this may also affect the coat. The size of the spot usually has to do with when in the development the mutation occurred. If early and that group of cells continued to split and grow, then you can get a fairly large spot. If late, it will be a small spot or perhaps just a hair or two.

• The other theory is that it occurs from the melanocytes (A pigment-producing cell in the skin, hair and eye that determines their color) migrating away from the neural crest (where melanocytes originate) during development..

The following is a list of known purebreds with black pigmentation on their tongues...
Labrador Retriever, Golden Retriever, Newfoundland, Samoyed, German Shepherd, Aussies, Akita, Belgian Sheepdog, Collie, Tervuren, Malinois, Fila Brasileiro, Cairn Terrier, Great Pyrenees, Keeshond, Airedale, Doberman Pinscher, Bouvier de Flandres, Australian Shepherd, Australian Cattle Dog, Pug, Shiba Inu, Dalmatian, Flat-coated Retriever, Gordon Setters, Shar-Pei, Cocker Spaniel, Siberian Husky, 
Rottweiler, Rhodesian Ridgeback, and of course the Chow.

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If the allele is dominant, only 1 copy is required to express the trait; if recessive then 2 copies are required to express the trait.
Upper case letters are traditionally used to represent dominant traits. Thus for a dominant trait, either AA or Aa will express the particular characteristic.
Lower case letters for recessive traits. For a recessive trait only aa will express the characteristic. The heterozygote (Aa) will be a carrier - clinically unaffected but able to pass the harmful allele to the offspring.

Example: (From website linked at the bottom of this page)

Progressive retinal atrophy (PRA) causes blindness in many breeds. P represents the dominant allele, and p the recessive allele. Since PRA is a recessive trait, p is the affected allele, and P the normal allele.

The genotypes PP and pp are homozygous. Dogs with the genotype PP have normal sight and those with pp are affected.

Pp is heterozygous. These animal have normal sight but are carriers. They will pass the allele for progressive retinal atrophy to approximately half their offspring.

Phenotypically, both PP and Pp have normal sight, but their genotype is different. At this time, as with most recessive disorders, there is no way to identify carriers (animals with the genotype Pp) until affected offspring are born.

Autosomal recessive - 
The most common mode of inheritance for genetic conditions in dogs. 
To be affected, the animal must inherit (genotype pp) 2 copies of the affected gene, 1 from each parent. 
Puppies that inherit genotype PP will be normal
Puppies that inherit genotype Pp will be normal, but will be carriers.
As long as carriers (Pp) are mated to normal animals (PP), the offspring will be unaffected but some will remain carriers. 
If 2 carriers are mated, some of the offspring (approximately 25%) will be affected.
The odds increase if one were to breed a parent affected with the disorder (pp) to a carrier (Pp). In such a situation, there is a 50% risk that the offspring will be affected (any unaffected offspring will be carriers)
In contrast, if one parent is affected (pp) and the other is neither affected nor a carrier (PP), none of the children will be affected with the disorder. However, all will be carriers.

Sex-limited - In these traits, the gene is located on the X chromosome. 
Males have  X (chromosome from Dam) & Y (chromosome from Sire) = XY which simply means they are male.
Females have X (chromosome from Dam) & X (chromosome from Sire) = XX
So if a mother who is a carrier for a harmful recessive gene (Xx) passes the recessive gene (x) to her daughter, the daughter will be an unaffected carrier, but her sons who receive that gene will be affected.

Polygenetic - Scientists do not yet know which genes are involved, or how many genes. The gene expression is influenced by a variety of factors including gender, nutrition, breed, rate of growth, and amount of exercise. 
These traits are quantitative traits - that is, there is a wide range within the population. Such traits include height, weight, character, working abilities, and some genetic defects. Heritability varies within different breeds and within different populations of a particular breed.

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