The impact of wash water quality and milk temperature monitoring on milk quality on Ontario dairy farms
This thesis describes the relationship between bacterial contamination of wash water and elevated bacteria counts in raw milk on dairy farms, and the impact of Time Temperature Recorder's (TTR) on the bacterial content of raw milk. The installation of TTR's and the testing of water on Ontario dairy farms are intended to decrease the risk of bacterial contamination of raw milk under the Canadian Quality Milk Program. 'E. coli' contamination of point-of-use water samples was associated with an increase in raw milk bacteria levels. Several geographic clusters of 'E. coli' and coliform water contamination were identified across southern Ontario. The TTR's monitor the harvesting, handling and storage of raw milk, as well as the cleaning of the bulk tank and pipelines. Regulatory alarms indicating problems in these areas differed between the winter and summer months. Farms with a TTR had significantly lower milk bacteria levels than farms without a TTR.