Chlorine Dioxide Teat Disinfectant: A Clinical Study on Bactericidal Efficacy and Safety in Dairy Cows in Comparison with an Iodine Glycerin Disinfectant

This study evaluated the clinical bactericidal efficacy and safety of a novel chlorine dioxide teat disinfectant compared to a traditional iodine glycerin disinfectant in dairy cows. The randomized controlled trial included long-term natural exposure (100 cows) and teat surface disinfection (40 cows) experiments. Key metrics assessed were somatic cell count (SCC), teat skin health (dryness, roughness, hyperkeratosis), and bacterial reduction rates against <i>Staphylococcus aureus</i>, <i>Escherichia coli</i>, and <i>Streptococcus</i> spp. Results demonstrated that the chlorine dioxide teat disinfectant achieved comparable to iodine glycerin disinfectant in controlling the rate of SCC exceeding the threhold (3.57% vs. 4.50% at day 10; <i>p</i> > 0.05), teat skin dryness, end roughness, and hyperkeratosis severity showed no significant differences over time or between iodine glycerin (control) and chlorine dioxide teat disinfectant groups (all <i>p</i> > 0.05). Notably, quantitative bacteriological assessment revealed significantly higher log₁₀ reduction values for chlorine dioxide teat disinfectant (2.14) versus iodine glycerin controls (1.93; <i>p</i> < 0.05). Microbiological evaluation further demonstrated complete pathogen eradication (100.00%) by chlorine dioxide across all isolates (<i>S. aureus</i>, <i>E. coli</i>, <i>Streptococcus</i> spp.), whereas iodine glycerin achieved 99.84–100.00% bactericidal rates. The findings suggest that chlorine dioxide teat disinfectant is a sustainable and effective alternative to iodine glycerin disinfectant, offering robust antimicrobial activity, improved teat condition, and reduced residue concerns. Further multicenter studies are warranted to validate these outcomes under diverse herd management conditions.