Biofilm formation and its impact on environmental survival and antibiotic resistance of Mycoplasma anserisalpingitidis strains.

Several Mycoplasma species can form biofilm, facilitating their survival in the environment, and shielding them from therapeutic agents. The aim of this study was to examine the biofilm-forming ability and its potential effects on environmental survival and antibiotic resistance in Mycoplasma anserisalpingitidis, the clinically and economically most important waterfowl Mycoplasma species. The biofilm-forming ability of 32 M. anserisalpingitidis strains was examined by crystal violet assay. Biofilms and planktonic cultures of the selected strains were exposed to a temperature of 50 °C (20 and 30 min), to desiccation at room temperature (16 and 24 h), or to various concentrations of eight different antibiotics. Crystal violet staining revealed great diversity in the biofilm-forming ability of the 32 tested M. anserisalpingitidis strains, with positive staining in more than half of them. Biofilms were found to be more resistant to heat and desiccation than planktonic cultures, while no correlation was shown between biofilm formation and antibiotic susceptibility. Our results indicate that M. anserisalpingitidis biofilms may contribute to the persistence of the organisms in the environment, which should be taken into account for proper management. Antibiotic susceptibility was not affected by biofilm formation; however, it is important to note that correlations were examined only in vitro.