The importance of mastitis in dairy production in Brazil

Abstract

Mastitis is an inflammation of the mammary gland that causes severe economic losses due to reduced milk production, expence on pharmaceuticals, veterinary care, discarding of milk after treatment and discarding of affected animals. This inflammatory process may have distinct origins, but all cases of economic importance are caused by microorganisms. According to their origin and means of transmission, the main etiological agents were put together in two groups, contagious microorganisms (Streptococcus agalactiae, Staphylococcus sp, e Corynebacterium bovis) transmitted mainly during rnilking and environmental microorganisms (Streptococcus uberis, Enterobacteriaceae, fungos, algae of the genus Prototheca, etc.).Clinical mastitis is characterized by visible changes in mammary gland and/or in milk. Subclinical mastitis is characterized by reduction of milk production although no signs of inflammatory process may be seen. Mastitis control programs have the objective of igniting the prevalence of mastitis to economic acceptable levels according to the particular features of each dairy farm. The program is based in four aspects: source of infection - diagnosis, treatment or discarding of the animals; susceptible - nutrition, selection of more resistant animals and milking hygiene; means of transmission - milking hygiene and environmental hygiene; awareness of the problem by the producers due to the economic losses and sanitary education of the dairyman. The estimated economic losses due to mastitis on brazilian dairy herds were around US$332/cow/year, higher than the estimated losses in the United States, that were around US$200/cow/year.