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Bovine chorioptic mange, caused by Chorioptes texan us (Hirst, 1 924) is reported. Eighty three (80,5 %) out of 103 Israeli Friesian herds, surveyed in the years 1983-1987, were found infested. Most of the animais infested were cows while prevalence in female calves and heifers was much lower (81,9 %, 12% and 6% of the infested herds respectively). In most cases the lesions were limited to the root of the tai! and the escutcheon. Three cases of generalized chorioptic mange were registered in the infested herds. The clinical manifestations are described. The taxonomie characters of C. texanus are described and compared to those of C. bovis found in Israel in sheep and goats. RÉSUMÉ : La manifestation de la gâle chorioptique des bovins, causée par Chorioptes texanus (Hirst, 1924), est rapportée. Sur cent trois établissements laitiers, de la race bovine Israeli-Friensian, examinés dans les années 1983-1987, quatre-vingt trois établissements (80,5 %) étaient infestés par la gâle chorioptique. La grande majorité des animaux infestés étaient des vaches tandis que la prévalence de cette gâle chez les veaux femelles et chez les génisses a été beaucoup plus basse (81,9 %, 12% et 6% des établissements infestés respectivement). Dans la plupart des cas les lésions parasitaires ont été limitées à la racine de la queue et dans la région périnéalle. Trois cas de gâle généralisée on été détectés. Les établissements infestés n'ont pas enregistré de dégâts économiques. Les manifestations cliniques sont décrites ainsi que les caractères taxonomiques de C. texanus, comparés à ceux de C. bovis, isolé souvent des ovins et des caprins en Israël. INTRODUCTION (HIRST, 1924) and in reindeer in Canada (SwEATMAN, 1958). In Israel, chorioptic mange has been studied in cattle (YERUHAM, 1981) and the causal agent identified as C.b. Since then numerous field cases were diagnosed in cattle, mites collected and classified. Furthermore, of most the preserved, previously collected mite specimens have been revised and compared to the chorioptic mites Chorioptic mange in domestic and wild ruminants is caused by Chorioptes bovis (Hering, 1845) and Chorioptes texanus (Hirst, 1924). C. bovis (C.b) has a worldwide distribution, infesting cattle, sheep and horses (SWEATMAN, 1957). C. texanus (C.t.) has been described only twice, i.e. in goats in Texas * Department of Entomo1ogy, The Kimron Veterinary Institute, P.O.B. 12, Beit-Dagan, 50250, Israel. ** "Hachak1ait ", Gedera, Israel. Acarologia, t. XXX, fasc. 4, 1989. collected from sheep and goats. The results are described in the present communication. MA TERIAL AND METHODS Skin scrapings were taken from mange-like lesions in animais in 103 Israeli-Friesian dairy cattle herds in the years 1983-1987 and were examined for the presence of sarcoptiform mites. The samples were examined under a Wild dissecting microscope (x 50). The mites were deposited in lactic acid on a heated plate (35°C) for clarification and then into Berlese for final identification using a phase contrast Wild microscope (x 40). Samples that were found negative for mites in the direct examination were digested (PRITCHARD, 1982) and re-examined. Measurements were carried out with a micrometrie ocular. Specimens collected previously were also revised. The mites were classified and compared to samples of C.b. collected from sheep and goats, using the keys of SWEATMAN (1958) and FAIN (1975).