OCCURRENCE OF ETIOLOGICAL AGENTS CAUSING SUBCLINICAL MASTITIS IN MORADA NOVA AND SANTA INÊS EWES / Ocorrência dos agentes etiológicos causadores de mastite subclínica em ovelhas das raças morada nova e Santa Inês.

E ste trabalho objetivou determinar a ocorrencia dos agentes etiologicos da mastite subclinica em ovelhas das racas Santa Ines e Morada Nova e as susceptibilidades das duas racas em desenvolver a doenca quando submetidas as mesmas condicoes de manejo. Analisou-se 250 mamas de 130 ovelhas da raca Santa Ines e 143 mamas de 77 ovelhas da raca Morada Nova. No momento da secagem, realizaram-se o California Mastitis Test , contagem de celulas somaticas e analises microbiologicas. As ocorrencias da mastite subclinica nas diferentes racas foram analisadas utilizando o teste de qui-quadrado ajustando os valores de acordo com a correcao de continuidade de Yates . As ocorrencias de animais com mastite subclinica infecciosa foram de 33,1% e de 35,1% nas ovelhas Santa Ines e Morada Nova, respectivamente. Dentre as mamas avaliadas das ovelhas Santa Ines, 20,4% apresentaram mastite subclinica com a seguinte etiologia infecciosa: Staphylococcus coagulase-negativos (ECN) (46%), Coliformes (22%), Streptococcus spp. (12%), Corynebacterium spp. (6%), Micrococcus spp. (6%), Staphylococcus aureus (2%), Staphylococcus coagulase-positivos (2%) e infeccao mista de ECN e Streptococcus spp. (4%). Das mamas avaliadas das ovelhas Morada Nova, 21% apresentaram mastite subclinica com os seguintes agentes etiologicos e respectivas ocorrencias: ECN (56,7%), Coliformes (13,3%), Corynebacterium spp. (10,0%), Staphylococcus aureus (10,0%), Micrococcus spp. (6,7%) e Streptococcus spp. (3,3%). Os ECN podem ser considerados os mais importantes agentes etiologicos da mastite subclinica ovina. Ovelhas das racas Santa Ines e Morada Nova apresentam as mesmas chances de desenvolver mastites subclinicas quando submetidas ao mesmo sistema de manejo. SUMMARY This study aimed to determine the occurrence of the etiologic agents of subclinical mastitis in Santa Ines and Morada Nova ewes and the susceptibility of this two breeds to develop the disease when submitted to the same management conditions. We analyzed 250 mammary glands of 130 Santa Ines ewes and 143 mammary gland s of 77 Morada Nova ewes. At drying off, California Mastitis Test , somatic cell counts and microbiological analysis were performed. The occurrences of subclinical mastitis in differently breeds were analyzed using the chi-square adjusting the values ​​according to the Yates continuity correction. The infectious subclinical mastitis was 33.1% and 35.1% in Santa Ines ewes and Morada Nova, respectively. Among the mammary glands evalueted of Santa Ines ewes, 20.4% had subclinical mastitis with the following infectious etiology: Cougulase Negative Staphylococcus (CNS) (46%), Coliforms (22.0%), Streptococcus spp. (12.0%), Corynebacterium spp. (6%), Micrococcus spp. (6.0%), Staphylococcus aureus (2.0%), Cougulase Positive Staphylococcus (2.0%) and mixed infection of CNS and Streptococcus spp. (4.0%). Among the mammary glands evalueted of Morada Nova ewes, 21% had subclinical mastitis with the following etiologic agents and their occurrences: CNS (56.7%), Coliforms (13.3%), Corynebacterium spp. (10.0%), Staphylococcus aureus (10.0%), Micrococcus spp. (6.7%) and Streptococcus spp. (3.3%). The CNS can be considered the most important etiological agents of subclinical mastitis in sheep. Ewes of Santa Ines and Morada Nova have the same chances of developing sub-clinical mastitis when subjected to the same management system.