Evaluation of teat dips with excised teats.

Thirty-eight teat dip formulations were evaluated for germicidal activity against Staphylococcus aureus and Streptococcus agalactiae with an excised teat model. Twenty-six of 27 iodophor products provided log reductions greater than 3 against Staphylococcus aureus, but only 13 against Streptococcus agalactiae. Log reductions obtained with two .2% quaternary ammonium and .5% cetylpyridium chloride products were greater than 4 against both organisms. A 1% benzyl alcohol formulation provided log reductions of 3.86 and 4.30 against Staphylococcus aureus and Streptococcus agalactiae. Germicidal activities of six novel formulations containing sodium chlorite were determined. Two products were effective against Staphylococcus aureus and Streptococcus agalactiae with log reductions greater than 4. One product provided a log reduction of 3; three products were ineffective.