[Lysogeny in Escherichia coli isolated from birds and the spectrum of the lytic action of isolated phage].

Studies was the lysogenicity in a total of 70 strains of Escherichia coli isolated from birds. As many as 19 lysogeneic strains were isolated, yielding 19 phages that had the signature of lysogenic strains. Two serologic groups of phages were established by means of the neutralization reaction. It was found that phages 30 and 229, representing the two serologic groups of bacteriophages could lyse up to 44 per cent of the E. coli strains isolated from birds, 7 per cent of those isolated from calves, and 4 per cent of those from pigs. Out of 74 Salmonella strains, belonging to ten species, the same phages lysed two strains of Salmonella newport and 1 strain of Salmonella anatum. It is believed that phage lysis could be used to establish the source of infection and to evaluate the effectiveness of the prophylactic measures applied, incl. disinfection.