Diversity in nicotinamide-adenine dinucleotide requirement for the growth of different strains of Mycoplasma synoviae

The type strain WVt 1853 and field strains SG, N26 and A642 of Mycoplasma synoviae were examined for their requirement for nicotinamide-adenine dinucleotide (NAU) for in vitro growth. All the strains grew and could be repeatedly passaged in Frey broth medium supplemented with filter-sterilised SAD. In modified Frey broth medium from which NAD was omitted and broth medium for which the supplements including yeast extract and SADwere auto-claved, only strains N26 and A642 could be crown and passaged. The growth curves of strain N26 determined in broth media with and without NAD were similar. These results Indicated thai there are differences in NAD-require-ment for in vitro growth among strains of M synoviae.