Factors Negatively Influencing Microbial Contamination of Milk

The objective of this study was to analyse the influence of selected factors in relation to total bacterial counts (TBC) in bulk milk samples. Milk samples were tested in nine cowsheds of seven farms for a period of one year. The TBC values were determined by the automated estimation of bacterial counts in cow’s raw milk by directly counting the bacterial cells on a BactoScan 8000 apparatus. The highest average values of TBC were determined in loose bedding-free slatted-floor housing (42.122·10·ml) while the difference in lnTBC compared to loose bedded cubicle housing (TBC average 7.354·10·ml) and stanchion bedded housing (TBC average 10.735·10·ml) was statistically highly significant (p < 0.001). We also proved a statistically highly significant difference in lnTBC (p < 0.001) between farms using predipping (TBC average 8.443·10·ml) and farms without predipping (TBC average 14.518·10·ml); the difference in lnTBC between farms with summer grazing (TBC average 10.04·10·ml) and farms without grazing (TBC average 13.959·10·ml) was statistically significant (p < 0.05).