Inheritance of a lethal immunodeficiency disease of Arabian foals.

A fatal syndrome of certain Arabian foals which begins at about 25 days of age (range 14 to 46 days) and which runs a course of about 23 days (range 13 to 42 days) is described. The syndrome, which affected 17 foals on a single farm is further characterised by pneumonia, in some instances by dermatitis (dermatophilosis) and other infections, together with a progressive decline in health till death at about 49 days of age (range 34 to 77 days), despite intensive therapy. Four of the foals, on histopathological evidence, had adenviral pneumonia, in 2 foals there was histopathological evidence of an immunodeficiency disease and an adenovirus was isolated from 1 foal. It is argued, however, that the 17 foals were affected by a single, specific syndrome (an immunodeficiency disease) and that this disease is inherited as a simple, recessive, autosomal gene.