Pesq. Vet. Bras. 34(1):1-10, janeiro 2014 1 RESUMO.-A mastite em ovelhas da raça Santa Inês apresenta-se como um problema de grande proporção e gravidade e é dificilmente tratada com sucesso. O objetivo deste estudo foi caracterizar aspectos clínicos, epidemiológicos e etiológicos da mastite clínica em ovelhas de corte criadas no norte do Paraná. O presente estudo foi realizado entre os meses Mastits is infrequent in meat ewes. However Santa Ines ewes have a high incidence of this disease and it is severe and difficult to treat. The goal of this study was to characterize clinical, epidemiological and etiological aspects of clinical mastitis in meat ewes reared in the north of Parana, Brazil. Fifith four farms were visited from October 2009 to September 2010. The surveyed data included frequency, breeds of sheep affected, lamb mortality rates, main clinical signs, attempts and outcome of treatment, method and period of weaning and management features. Seventy ewes with clinical mastitis were fully examinated and samples of mammary secretion were asseptically taken for bacteriological culture. Mastitis was identified in 39 farms (72.3%) as a relevant problem (mean frequency was 6,74%). Chronic and acute mastitis were observed in 69% and 31% of the examinated ewes, respectively. In both cases, phlegmonous mastitis was the most prevalent form (65.5%). Coagulase negative Staphylococccus (CNS) was the main isolated microorganism (54.5%), followed by Staphylococcus aureus and Arcanobacterium pyogenes (11.5%, each one). Mannheimia haemolytica was found in two cases. The risk factors for clinical mastitis were intensive management system and Santa Ines breed. Weaning after 120 days of lactation and isolation of affected ewes were associated with lower frequency of mastitis. Preventive measures recommended are daily cleaning of facilities and delayed weaning, mainly in Santa Ines flocks.