Effects of premilking teat preparation on spores of anaerobes, bacteria, and iodine residues in milk.

Premilking teat preparations using individual paper or cotton towels for either 6 or 20 s to reduce bacteria and iodine residues from teat surfaces were determined through Latin square designs applied to 50 cows. A cotton towel used for 20 s was most effective in cleaning teats, probably because of the physical structure of the towel, physical action on teat surface, and scrubbing of the teat ends. Premilking teat preparation of 6 s was inadequate to clean teats and to avoid iodine residues in milk. Teat end erosions increased iodine residue in milk. Two days after a treatment period, iodine content in milk from iodophor-dipped groups was similar to that of the undipped control group. Against our expectation, teat dipping with a .25% iodophor teat dip caused higher iodine residue in milk than a .50% iodophor teat dip. Differences in formulations and inert ingredients of iodophor teat dips indicate a need for further studies.