Short Communication BACTERIOLOGICAL STUDY OF ETHIOPIAN ISOLATES OF DERMATOPHILUS CONGOLENSIS T. SAMUEL, F. TAREKE, G. WIRTU* AND T. KIROS Faculty of Veterinary Medicine (FVM), PO Box 34, Debrezeit, Ethiopia *Correspondence and present address: 1805 Grayland Street, #5, Blacksburg, VA 24060, USA Samuel, T., Tareke, F., Wirtu, G. and Kiros, T., 1998. Bacteriological study of Ethiopian isolates of Dermatophilus congolensis. Tropical Animal Health and Production, 30(3), 145^147 Dermatophilosis is widespread in Ethiopia. In indigenous zebu cattle, prevalences of 4.6^16.3% were reported from the south (Bogale, 1991), south-east (Berhanu, 1994) and north (Abraha, 1994). Cases of the disease are also frequent at the Faculty of Veterinary Medicine (FVM) clinic in central Ethiopia. Prevalence rates are generally higher in exotic genotypes. Siltan (1985), Berhanu (1994) and Abraha (1994) reported rates of 13.3%, 15% and 52.4% in crossbred cattle in central, northern and south- eastern regions respectively. However, bacteriological studies on the aetiological agent are limited. This study was therefore undertaken to ascertain some features of Ethiopian isolates of Dermatophilus congolensis. Samples were obtained from scabs in a cow and ewe, at Debrezeit, with typical ichthyotic lesions and from a camel in Borana region. The camel lesions were discrete and raised measuring 2 to 3 mm in diameter and distributed on the sides of the body from the neck to the thighs. Bacterial isolation was conducted by a combination of techniques (Haalstra, 1965; Cottral, 1978) with slight modi¢cations. Scabs were minced into ¢ne pieces and placed in sterile tubes with enough saline to soak them. The tubes were kept in a water bath at 358C for about 1 h and then placed in a candle jar with loosened plugs for 15 min. Loopfuls from the surface were inoculated onto duplicate nutrient and tryptose agar plates and incubated aerobically and in a candle jar. Blood agar and serum broth cultures were subsequently made from these primary isolates. Biochemical tests included inoculations of urea and TSI agar slants (Oxoid, England), peptone water and (MR^VP) (Methyl red^Voges Proskauer) media (Difco, USA). Additionally, phenol red broths (Difco, USA) with glucose, sorbitol, maltose, sucrose, xylose and ra¤nose in di¡erent tubes were inoculated for fermentation tests (Gordon, 1964). Results were read at 24, 48, 96 h and 7 day intervals. Nutrient and tryptose agar plates showed rough tiny, pin-point or painted colonies adherentto a pitted medium. Candle jar colonies were larger in size. On blood agar plates, growths were more raised with either greyish-white or yellowish colours. In serumbroths, growths were £u¡y £oating/suspended and cotton-like or granulated membranous colonies adherent to the tubes.The rest of the medium consistently remained clear. Tropical Animal Health and Production, 30 (1998) 145^147 # 1998 Kluwer Academic Publishers. Printed in the Netherlands 145