The inherited conditions
of aortic stenosis (a narrowing above the aortic heart valve or the aortic valve itself), atopy /
allergic dermatitis (skin allergies), gastric dilatation volvulus (bloat / stomach dilation), early
onset cataracts (a clouding
of the lens inside the eye), dilated cardiomyopathy (enlargement
of the chambers
of the heart and thinning
of the muscle wall), elbow dysplasia (abnormal growth
of tissues that leads to malformation and degeneration
of the joint), epilepsy (brain seizures), hypothyroidism (underactive production
of thyroid hormones), intervertebral disk
disease (problems with the disks between the vertebrae
of the spine leading to neurological problems), and hepatic portosystemic shunt (an abnormal blood circulation where blood is diverted around the liver rather than into it) are more prevalent in purebred dogs than in mixed - breed.