WINTER EVALUATION OF A POSTMILKING POWDERED TEAT DIP

A powdered teat dip designed for winter usage was evaluated for bacter iological efficacy and teat conditioning qualities. A positive control , natural exposure field trial was conducted for 3 mo on 509 lactating cows. Two sets of cows, primiparous and multiparous, were used. The t rial compared efficacy of a powdered teat dip with a teat dip of 1% io dine plus 10% glycerin. Bacteriological efficacy among primiparous cow s was equivalent for all major mastitis pathogens, environmental patho gens, and streptococci other than Streptococcus agalactiae. Efficacy w as not equivalent against coagulase-negative staphylococci and all mas titis pathogens. Results suggested that the positive control product w as more efficacious. Among multiparous cows, efficacy was equivalent a gainst environmental mastitis pathogens and bacteriologically negative , clinical mastitis. The products were not equivalent against Staphylo coccus aureus, coagulase-negative staphylococci, or all major mastitis pathogens, once again suggesting that the positive control product wa s more efficacious. Data indicated that germicidal activity of the pow dered dip was not sufficient to reduce the incidence of new IMI caused by contagious or minor pathogens normally associated with teat skin. Application of a powdered postmilking teat dip during 3 winter mo in I daho resulted in improved teat end condition among primiparous and mul tiparous dairy cows. Teat skin condition improved among primiparous bu t not among multiparous cows.