Formação de biofilmes microbianos em diferentes materiais para equipamentos de ordenha em fazenda leiteira

Abstract

The presence of microbial biofilm attached milking equipment, formed by inadequate cleaning, are a constant source of contamination of the milking animals and which goes to the milk industry, compromising both the animal health and the quality of the milk produced. The objective of this study was to identify strains of Staphylococcus aureus, Staphylococcus epidermidis and Escherichia coli producing biofilm in cows with mastitis milk samples, milk samples from the expansion tank and swabs of the set of liners for milking, and evaluate training biofilm coatings on four different stainless steel, comprising polypropylene, polypropylene with zeolite to 3% polypropylene with 6% zeolite and polypropylene with glass and silver. For phenotypic characterization of the strains were used for tests with congo red agar (CRA) microplate assay with crystal violet dye, counting colony forming units of biofilm cells, extracting the matrix by sonication, quantification of extracellular proteins and polysaccharides, confirmed by analysis of images generated by laser confocal microscopy. Of the 294 samples analyzed were identified eight strains of Staphylococcus aureus, Staphylococcus epidermidis and 22 three Escherichia coli, those eight, 1:11 were producing biofilm, respectively. Escherichia coli bacteria that has been formed over biofilm in all materials, and for coating stainless steel comprising polypropylene with 6% zeolite had a higher bond biofilm when compared to polypropylene and glass with silver (p < 0,05). The material consists of silver, glass and polypropylene had microbial biofilms of grip, but at a lower concentration than the other materials tested, representing themselves in this way as an alternative to coat surfaces of utensils and equipment related to milking.