Author(s): SOUZA, G. N. de; RUBIALE, L.; FARIA, C. G. de; MORAES, L. C. D. de

Summary: Milk is produced in all Brazilian regions, in more than a million farms. The range of milk producers varies from a larger proportion (80%) of smallholders that use crossbred cows (Holstein x Zebu cattle) to large farms with Holstein/Friesian cows. Data about subclinical mastitis and somatic cell counts (SCC) is scarce and incomplete, although parameters for SCC are now used by public and private sectors to evaluate milk quality. We aimed to evaluate the influence of the year season on the SCC of both the individual Holstein /Friesian cows and the bulk tank milk (BTM) of crossbred herds. Milk samples from individual cows (n=113,904), and from BTM (n=468,282) representing a period of three years (2006-2008), were available for analysis. SCC values were divided in seven classes (from <50,000 cells/ml to >1,600,000 cells/ml). Considering a threshold of 200,000 cells for individual cows, 46.5% and 48.3% of milk samples were found to be positive for subclinical mastitis during the dry and rainy seasons, respectively. As for BTM, 46.3% and 49.9% of samples were found above a threshold of 400,000 cells during those two seasons respectively. There was a significant reduction of SCC (p<0.001) during the dry season. The high prevalence of high SCC in both individual cows and BTM indicates that subclinical mastitis is both a health problem and a milk quality issue. These results indicate that additional specific measures to control mastitis need to be implemented during the rainy season.

Publication year: 2009

Types of publication: Paper in annals and proceedings

Unit: Embrapa Dairy Cattle

Keywords: Contagem de células somáticas, Leite, Qualidade, Sanidade Animal