Clinical, hematologic, and biochemical features of a syndrome in Bernese mountain dogs characterized by hepatocerebellar degeneration.

Seven related Bernese Mountain Dogs developed a syndrome Characterized by progressive cerebellar and hepatic disease. Clinically, stiffness in the hind limbs, mild incoordination, and a slight head tremor were first noticeable when pups were 4 to 6 weeks old. The condition progressed, causing pups to assume a wide-based stance. Other signs included head bobbing, spontaneous nystagmus, and, finally, paresis. Hematologic findings included leukocytosis with a left shift; normocytic, normochromic anemia; hypoproteinemia, low serum creatinine, and urea nitrogen concentrations; excessive fasting plasma ammonia concentration; and an increase in concentration of serum bile acids. Portal venography performed on 1 dog revealed a small liver and extensive extrahepatic varicosities. Necropsy revealed cerebellar hypoplasia, nodular liver, extensive abdominal varicosities, and ascites. Histologically, degeneration and depletion of Purkinje's cells and vacuolation, degeneration, and nodular regeneration of hepatic tissues were evident. Preliminary analysis of the pedigree was suggestive of an autosomal recessive pattern of inheritance.