Avaliação da estabilidade do cloridrato de polihexametileno biguanida em pedilúvio para bovinos

Abstract

The present study evaluated the stability of the polihexametilene biguanide hydrochloride solution (PHMB) used in footbath as disinfectant. Three concentrations (1%, 3% and 5%) were appraised for a period of seven days. During that period, ten healthy animals passed three times through the footbath, with intervals of 48 hours among the passages. Of each solution four samples were picked, with intervals of 48 hours, and the first crop was accomplished immediately as solution was prepared. The physical-chemistry analysis consisted of the determination of pH and the concentration of PHMB. The microbiological analyses consisted of aerobic microorganism or optional mesophilics and of anaerobics mesophilics. The microbial growth was based on an adaptation of the methodology proposed by Andrade and Macêdo (1996). The selection of the best concentration was based on the smallest averages of the anaerobic mesophilics, in the smallest aerobic or optional mesophilics, in the smallest cost/benefit of the solution and in the animal comfort. The physical and chemical characteristics remained practically stable and no difference was observed in the microbial growth among the concentrations of 5% and 1% and only Staphylococcus epidermidis and Bacillus spp. were isolated. The use of PHMB at 1% was considered to be the most viable regarding the economical point of view.