Increased use of after-milking teat dips has resulted in the appearance of many new teat dips and a need for methods of evaluation of efficacy. A method was developed for determining the ability of a disinfectant to kill bacteria on the teat ends. Results from several known efficacious products indicated an approximate 95% reduction in bacterial flora. Additional data are presented on some experimental products. This method will provide a measure of effectiveness of a product on teat-skin disinfection. The effect of some changes in the testing procedure on bacterial reduction is demonstrated: 1) Increased times between inoculation and dipping and between dipping and swabbing tended to decrease recoveries on control teats. 2) Saline dips on control teats provided increased recoveries of test organisms.
Bibliographical noteFunding Information:
This study was supported by funds from the H. B. Fuller Co., Monarch Chemicals Division, and the Minnesota Agricultural Experiment Station, Grant No. 0302-4826-19. The authors wish to acknowledge the technical assistance of Peggy Wheelock and Andrew Johnson. We also acknowledge James Jezeski for review of the manuscript.