Hypercholesterolemia in Shetland sheepdogs

Plasma lipoprotein cholesterol in 64 clinically healthy Shetland sheepdogs was evaluated to assess whether the breed is more susceptible to hyperchole sterolemia. The incidence of hypercholesterolemia was clearly higher in She tland sheepdogs and mean plasma cholesterol level was significantly higher in Shetland sheepdogs than in control dogs. Blood biochemical examinations did not evidence the abnormalities, which imply the causative disorders, an d thyroid hormone levels were not significantly different from the controls . These results suggest that the cholesterolemia is a primary disorder. Cho lesterol fractionation by agarose gel electrophoresis and ultracentrifugati on revealed that accumulation of alpha (2)-migrating lipoproteins was the c ommon characteristic of dogs showing cholesterol level over 250 mg/dl in th e breed. Increase in pre beta similar to beta -lipoproteins was also found in Shetland sheepdogs with marked hypercholesterolemia over 500 mg/dl. Ther efore, Shetland sheepdogs may include more dogs with primary disorders in l ipoprotein metabolism, which cause hypercholesterolemia, at least in Japan.