No abstract

Udder preparations that wet both udder surfaces and teats had the highest standard plate count in milk compared with methods that wet teats only. Physical action of cleaning teats with a dry towel lowered bacterial count compared with preparations wetting both udder surfaces and teats. Methods resulting in lowest bacterial counts were the use of water hose, wet towel, or premilking disinfectant teat dip followed by drying with paper towels. Counts of coliform and Staphylococcus sp. followed similar trends. In most comparisons, addition of udder wash sanitizer was of marginal or no benefit. Standard plate count of teat rinses after udder preparation confirmed the benefit of cleaning and drying teats. Physical manipulation of teats during cleaning was essential for lowering sediment in milk. Drying of teats with a paper towel for at least 10 s after dipping with a 1% iodophor disinfectant dip was essential for reducing iodine residue. Both premilking and postmilking disinfectant teat dipping with a 1% iodophor teat dip caused higher iodine residue in milk than premilking disinfectant dip with subsequent drying. A .5% iodophor teat dip contributed less iodine in milk than a 1% iodophor teat dip. Premilking udder preparation affects bacterial count, sediment, and iodine residue in milk.

No abstract

Udder preparations of wet towel plus drying and .1% iodophor premilking teat dipping plus drying were compared with no preparation to determine effects on number of new intramammary infections. Teats of 84 cows were challenged (5 d/wk) for 18 wk with a culture broth of Streptococcus uberis 3 h prior to each p.m. milking to stimulate environmental contamination. Wet towel plus drying and premilking teat dipping plus drying significantly reduced number of new intramammary infections compared to no preparation. Cleaning with water or dipping with a premilking teat dip and manual drying of teats may have contributed to the reduction in number of new infections. Premilking teat dipping plus drying further reduced number of new infections compared to use of wet towel plus drying. Apparently, teat dipping was more effective in reducing the number of new infections than water used with the wet towel. This study showed that udder preparations can affect udder health when an experimental bacterial challenge is applied.