Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of Bern, Bern, Switzerland.
Clinic for Ruminants, Vetsuisse Faculty, University of Bern, Bern, Switzerland.
PLoS One. 2020 Feb 13;15(2):e0229066. doi: 10.1371/journal.pone.0229066. eCollection 2020.
A footbath-based control program for ovine footrot, a contagious disease caused by Dichelobacter nodosus, will be implemented in Switzerland. The currently used footbath disinfectants formaldehyde, zinc sulfate and copper sulfate are carcinogenic or environmental pollutants. Hence, the aim of this study was to identify alternative disinfectants, which are highly effective, non-carcinogenic, environmentally acceptable, inexpensive, available as concentrate and suitable for licensing. The antimicrobial effect of a series of potential chemicals such as lactic acid, propionic acid, hydrogen peroxide, sodium hypochlorite, octenidine dihydrochloride, chlorocresol, Ampholyt 20 and the registered biocide DESINTEC® Hoof Care Special D (Desintec) were investigated by culture based in vitro testing. The microcidal effect of various Desintec concentrations were then compared against routinely used 4% formaldehyde and 10% zinc sulfate in ex vivo assays on sheep feet from slaughter. For this purpose a newly established PMA (propidium monoazid) real-time PCR using the improved dye PMAxx™ was applied that allows discrimination of viable and dead D. nodosus. In the ex vivo experiments, 4% formaldehyde was significantly more effective than 10% zinc sulfate and was chosen as positive control for assessing the new disinfectant. The disinfectant effect of Desintec in a minimal concentration of 6% was equally effective as 4% formaldehyde, meaning that it offers a comparable antimicrobial effect against virulent D. nodosus. In conclusion, Desintec is a promising disinfectant for replacing formaldehyde, copper sulfate and zinc sulfate in footbaths against footrot.
瑞士将实施一种基于足浴的绵羊腐蹄病（一种由坏死梭杆菌引起的传染性疾病）控制方案。目前使用的足浴消毒剂甲醛、硫酸锌和硫酸铜具有致癌性或环境污染性。因此，本研究旨在寻找替代消毒剂，这些消毒剂应具有高效、非致癌、环境可接受、价格低廉、浓缩可用且适合许可的特点。通过基于培养的体外试验，研究了一系列潜在化学物质（如乳酸、丙酸、过氧化氢、次氯酸钠、双氯己定二盐酸盐、氯甲酚、 Ampholyt 20 和注册杀菌剂 DESINTEC® Hoof Care Special D（Desintec））的抗菌效果。然后，在绵羊屠体的离体试验中，比较了各种 Desintec 浓度与常规使用的 4%甲醛和 10%硫酸锌的杀菌效果。为此，建立了一种新的 PMA（吖啶单叠氮化物）实时 PCR，使用改良染料 PMAxx™，可以区分存活和死亡的坏死梭杆菌。在离体实验中，4%甲醛比 10%硫酸锌的效果明显更好，因此被选为评估新型消毒剂的阳性对照。Desintec 的最低浓度为 6%时，其杀菌效果与 4%甲醛相当，这意味着它对毒力较强的坏死梭杆菌具有相当的抗菌作用。总之，Desintec 是一种有前途的消毒剂，可以替代甲醛、硫酸铜和硫酸锌用于治疗腐蹄病的足浴。
