Comparative studies of the persistence of animal mycoplasmas under different environmental conditions

A comparison of the persistence of mycoplasmas in animals was carried out. When inoculated into liquid media, strains of Mycoplasma bovis, M. arginini , Acholeplasma laidlawii, and A. axanthum persisted for 59-185 days post-in oculation, The survival periods were not significantly influenced by temper ature (4, 30, 37 degreesC, and room temperature). The survival periods for M. bovigenitalium, M. gallisepticum, M. bovirhinis, and M. gateae ranged fr om <7 to 185 days depending on medium components and temperature. Further, it was deter-mined that strains of M. bovigenitalium, M. bovis, M. bovirhin is, M. arginini, and A. laidlawii persisted in a dry paper disc for at most 28, 126, 154, 56 and over > 168 days at 4 degreesC, respectively. At 4 deg reesC, strains of M. gallisepticum, M. columborale, M. edwardii, M. felis. and M. gateae survived for at most 28, 21, 42, 28, 28 and 70 days, respecti vely. At 30 degreesC, strains of M. bovis, M. bovirhinis, M. arginini, A. l aidlawii, and M, gallisepticum persisted for at most 28, 84, 56, > 168 and 14 days, respectively, but strains of M. gallisepticum, M. columborale, M. edwardii, M. felis. M. gateae, and U. diversum did not survive for more tha n 14 days. In an outdoor environment, strains of M. bovirhinis and A. laidl awii survived for at most 28 and 14 days, respectively. Finally, it was fou nd that 14 isolates of M. gallisepticum persisted for periods similar to th ose of the reference strains. The results under dry conditions at a variety of temperatures presented contribute to understanding the epizootiology of mycoplasmal infections in the field. (C) 2001 Elsevier Science B.V. All ri ghts reserved.