Primary glaucoma in the Welsh springer spaniel

This paper reports 28 cases of primary angle closure glaucoma in the Welsh springer spaniel, a breed not previously reported to be affected by this condition. Females are affected more frequently than males (2–4:1). The age of onset ranges from 10 weeks to 10 years; however, the distribution is skewed towards the younger dog. The mode of inheritance appears to be dominant, which should make elimination of the trait through breeding control more straightforward. Gonioscopy on clinically affected and clinically normal dogs revealed three angle types; open (normal), partially open and partially closed (equivocal) and closed (affected). The equivocal cases may represent the heterozygous state and the closed the homozygous; alternatively the gene(s) may show variable expression.