Efficacies of chlorine dioxide and iodophor teat dips during experimental challenge with Staphylococcus aureus and Streptococcus agalactiae

We tested two postmilking teat dips for efficacy against Staphylococcus aur eus and Streptococcus agalactiae using experimental challenge procedures re commended by the National Mastitis Council. The chlorine dioxide teat dip t hat contained 0.7% sodium chlorite reduced the number of new intramammary i nfections (IMI) caused by Staph, aureus by 86.6% and reduced new IMI caused by Strep. agalactiae by 88.4%. The 0.5% iodophor teat dip reduced the numb er of new IMI caused by Staph. aureus by 92.9% and reduced the number of ne w IMI caused by Strep. agalactiae by 43.4%. Teat skin and teat end conditio ns were evaluated before and after the study, and no deleterious effects we re noted among dipped quarters compared with undipped control quarters for either teat dip.