Quality and microbiological aspects of bovine milk

Langoni H., Penachio D.S., Citadella J.C.C., Laurino F., Faccioli-Martins P.Y., Lucheis S.B., Menozzi B.D. & Silva A.V. 2011. [Quality and microbiological aspects of bovine milk.] Aspectos microbiologicos e de qualidade do leite bovino. Pesquisa Veterinaria Brasileira 31(12): 1059-1065. Departamento de Higiene Veterinaria e Saude Publica, Faculdade de Medicina Veterinaria e Zootecnia, Universidade Estadual Paulista, Botucatu, SP 18618-000, Brazil. E-mail:hlangoni@fmvz.unesp.br Mastitis is the main disease in dairy herds, presents high prevalence and constitutes a limiting factor on many farms in Brazil due to economic losses. Considering the etiological complexity of mastitis the present work aimed to study the etiological agents of mastitis and its influence on the quality of bovine milk. For this, a total of 1090 teats from dairy cows of 10 farms localized in Sao Paulo state were evaluated. The microbiological analysis of milk consisted of cultivating an 0.1mL aliquot of milk from each CMT-positive sample, or with clinical mastitis, on agar base medium containing 5% of ovine blood and on McConkey agar, incubating plates at 37 degrees C with observation of the microbial development at 24-hour intervals during three days. The microorganisms with highest frequency in mastitis were Corynebacterium bovis (29.52%), Streptococcus dysgalactiae (11.9%) and Staphylococcus aureus (10.48%). There was isolation of Candida krusei e Trichosporum spp. on Sabouraud dextrose agar. The averages of SCC and CFU from cows were variabl: eight (80%) farms were found to be within the limits established by regulation "Instrucao Normativa no 51" of the Ministry of Agriculture, and all farms were found to be within the limits for CFU. There was a positive correlation between CFU and SCC from milk in two of six farms statistically analyzed. It was concluded that mastitis is one of the factors that do not allow producer to reach the quality required by the government. Management and hygiene failures exist and must be corrected with instructions for the application of good production practices. Finally, monitoring of mastitis and milk quality in herds must be carried out, and accessible techniques as compound SCC can be used.