Bird Feathers and the Antirachitic Vitamin D

Abstract

ON reading the article entitled “The Antirachitic Vitamin D” in NATURE of Dec. 31, which has just come to hand, it struck me that it might be worth while to record the following. In my student days I at one time kept various hawks and owls as pets. Many of these were taken from the nest and hand-reared, their food being in the main lights in the broadest sense including liver. The majority died of rickets before attaining maturity. Among the exceptions were two favoured young tawny owls, which were fed almost exclusively on mice and sparrows. Success with these led me to add chicken heads complete with feathers and an occasional sparrow, also feathered, to the commissariat of the others. The only essential difference between the new diet and the old was the inclusion of feathers. The birds ceased to be troubled with rickets.