Mycological and some physiological studies of keratinophilic and other moulds associated with sheep wool

Wool samples of 50 healthy sheep collected from different localities at Ar' Ar in Saudi Arabia were examined for the presence of keratinophilic and other fungi using the hair plate technique. Forty-eight species and 2 varieties belonging to 20 genera were isolated on Sabouraud's dextrose agar at 25 degrees C. Two species of true dermatophytes were isolated: Trichophyton terrestre and T. rubrum in low frequency of occurrence. Chrysosporium, a well-know keratinophilic genus, was the predominant genus on sheep wool. Of 6 Chrysosporium species isolated C. tropicum, C. keratinophilum and C. indicum were the most prevalent. Several other moulds could colonize wool, and the most frequent species were members of the genera Aspergillus, Penicillium, Emericella, Chaetomium and Acremonium. 14 isolates of selected fungi were screened for their ability to produce protease and keratinase on solid media. All test fungi exhibited protease, but with varying degree. It was observed that true dermatophytes Trichophyton rubrum, T. terrestre and the keratinolytic fungi Chrysosporium tropicum and C. keratinophilum showed highly keratinolytic activity, but Emericella nidulans var. lata, E. quadrilineata and Penicillium funiculosum were not able to attack horse hair.