Prevalência da mastite subclínica e associação dos agentes etiológicos com a contagem de células somáticas de vacas leiteiras da região sudoeste do Paraná

Bovine mastitis is considered a major problem in the dairy farms, due to provokes large economic losses, well as damage to public health, through the placement of microorganisms in milk. The diagnosis is based on tests that verify the leukocyte content of milk, such as the somatic cell count (SCC) is an example of test used. Aiming to determine the prevalence of bovine mastitis and the effect of these etiologic agents involved on the SCC of dairy cows in the southwestern region of Parana were carried out collections of milk samples in 21 properties that had an average of nine animals, according to the towns with higher milk production: Realeza, Capanema, Santa Isabel do Oeste, Planalto e Nova Esperanca do Sudoeste. The herds were sampled twice within a year. Considering a total of 381 samples, it was found that the prevalence of mastitis in both collections ranged from 70.5% to 81.9%. From the SCC, samples with isolation of at least one mastitis pathogen showed median values of 346,000 cells/ mL and 121,000 cells /mL in the first and second test, respectively. The genus Staphylococcus was the most prevalent etiologic agent of mastitis in herds. In contrast, when comparing the pathogen and its relation to the number of somatic cells, Streptococcus agalactiae was the most pathogenic.