THE CONTAMINATION OF BIRDS' FEATHERS BY FUNGI

Fungi have regularly been recorded on feathers removed from birds. Cellulose-decomposing spores which are merely carried on the feathers were common on birds sampled in Britain, but were fewer than expected on the basis of random distribution on birds sampled in India. Hyaline-spored fungi were less common on Indian birds, and more abundant on British birds than expected. Keratinophilic fungi, which are related to the dermatophytes, were particularly associated with related groups of birds: thus Turdus spp. regularly yielded Arthroderma curreyi, and partridges were contaminated with Ctenomyces serratus. Chrysosporium spp. were widespread on birds in India and Britain. Where associations have been shown, feather fats from these birds stimulate, or do not depress the growth of the keratinophilic fungi. Otherwise, feather fats were inhibitory to the fungi. The temperature relationships of the fungi, showing no growth at 40°C, would explain the restriction of the keratinophilic fungi to the outer, contour feathers, and of dermatophytes mainly to the non-insulated parts of the birds' surface.