RESUMEN
The survival of Salmonella dublin exposed to visible sunlight, and heterotrophic bacteria in freshwater microcosms in the presence and absence of the photosensitizer proflavine, was studied. Enumeration of S. dublin and the heterotrophic bacteria showed that in both illuminated and nonilluminated systems (without proflavine) the bacteria remained viable and culturable for at least 6 days. The optimal proflavine concentration (no effect in the dark and a maximal photoinactivation of salmonellae after irradiation) was 2 mg l(-1). In contrast to S. dublin, the heterotrophic bacteria overcame the initial inhibitory effect of proflavine. The possible use of photosterilization against contamination with pathogenic bacteria in water model ecosystems, is discussed.
Asunto(s)
Fármacos Fotosensibilizantes/farmacología , Proflavina/farmacología , Salmonella/efectos de los fármacos , Salmonella/efectos de la radiación , Luz Solar , Bulgaria , Agua Dulce/microbiología , Aguas del Alcantarillado/microbiologíaRESUMEN
An experimental infection was induced in the European ground squirrel (Citellus citellus) by intraperitoneally injecting of 1 ml. of microbial suspension, containing 1 x 10(9) CFU (colony forming units) of Yersinia pseudotuberculosis, serotypes I and III. The infectious process was dynamically followed up from the 1st up to the 30th day, respectively. Account was rendered to the general condition, the internal body temperature and the mortality rate. The phagocytic activity of alveolar macrophages (aMa) and polymorphonuclear leucocytes (PMNL), isolated from the experimental animals, was also determined, as well as the degree of bacterial dissemination into the viscera and the histomorphological changes that found in the parenchymal organs. These investigations confirm the fact that the bacterial agent has a broad spectrum of alterations in the organism of the host--the European ground squirrel (Citellus citellus) in which the pseudotuberculosis develops as a generalized infection, especially pronounced in the animals that were infected with the serotype III.