Influence of water treatment and milking practices on milk quality

ABSTRACT The aim was to evaluate the influence of the use of sanitizing the water used on dairy farms, the management and the infrastructure on the dairy farm on the microbiological quality of water and milk. It was installed an equipment to chlorinate the water for a period of two weeks, in the water box of 20 dairy farms. In each dairy farm, water and milk samples were collected, being the first day (without chlorine: control), in the 7th and 14th day (chlorine), and 21 days after uninstalling the chlorinators (Chlorine-free: control). Microbiological analysis of water and milk (Somatic cell counts of milk, psychrotrophic bacteria, mesophilic and total coliforms) and physicochemical analysis of water were performed and a survey was applied to the farmers. The use of chlorine tablets in water improved (P<0.0001) the microbiological quality of water, but did not affect the microbiological quality of the milk (P>0.05). Management practices, hygiene and the structure of dairy farms are related to low microorganism counts in milk. In conclusion, chlorination of water improves the microbiological quality of water without affecting the microbiological quality of milk, which is improved by the adoption of good milking practices and adequate infrastructure

摘要：本研究旨在评估奶牛场用水消毒措施、牧场管理与基础设施对水和牛乳微生物品质的影响。研究人员在20个奶牛场的水箱中安装氯化消毒设备，实验周期为两周。分别于第1天（未投加氯，对照组）、第7天和第14天（加氯阶段），以及拆除消毒设备后21天（无氯对照组）采集水样与牛乳样本。对水样与牛乳样本开展微生物检测（包括牛乳体细胞计数、嗜冷菌、嗜温菌及总大肠菌群检测），并对水样进行理化分析，同时对牧场主开展问卷调查。结果显示，水中投加氯片可显著提升用水的微生物品质（P<0.0001），但对牛乳的微生物品质无显著影响（P>0.05）。牧场管理措施、卫生状况与牧场基础设施配置与牛乳中较低的微生物负荷呈显著相关。综上，饮水氯化可有效改善用水的微生物品质，且不会对牛乳的微生物品质产生负面影响；而采用规范的挤奶操作与完善的基础设施，可进一步提升牛乳的微生物品质。