Application of ozonated water for sanitizing cow teats and its influence on quality of milk

Abstract

This study evaluated the efficiency of ozonated water compared with chlorhexidine to disinfect teats of cattle and their influence on milk quality. 48 cows were separated in 2 groups of sanitation: (I) using ozonated water at 2 mg.L^-1 for 30s and (II) using 2%(v/v) chlorhexidine for 30s (standard methodology of disinfection). Before and after sanitation, swabs of teat were collected for carry out microbiological analysis. Additionally, after teats sanitation, the milking was performed and the obtained milk were evaluated by microbiological and physico-chemical parameters. The number of decimal reductions (NDR) reached after ozone sanitation was 2.52, 2.09 and 1.50 for aerobic mesophilic, Staphylococcus sp. and Enterobacteriaceae, respectively. The use of chlorhexidine promoted NRD of 2.38 (aerobic mesophilic), 2.04 (Staphylococcus sp.) and 1.16 (Enterobacteriaceae). Therefore, no significant differences were found between NRD caused by chlorhexidine and ozonated water. Moreover, no significant differences were observed in the psychrotrophic and aerobic mesophilic counts of the milk obtained after teats sanitation with ozonated water and chlorhexidine. Furthermore, it was observed that only samples obtained from cows treated with chlorhexidine showed the presence of Enterobacteriaceae. There were no changes in the physico-chemical parameters of milk obtained after both treatments. Thus, the ozonated water is a potential substitute of chlorhexidine for cows teats sanitation, resulting in similar microbiological reductions without risks of bacterial resistance development and waste generation.