The Effect of Serial Culture and Storage on the Protective Potential of a Competitive Exclusion Preparation

Cultura de fezes (Método de Exclusão Competitiva - EC) utilizada para prevenir a colonização cecal de aves por Salmonella enterica serovar Enteritidis (SE) foi submetida a cultivos seriados para evitar a presença de patógenos e, após o tratamento mais adequado, foi armazenada em temperatura de refrigeração antes do seu uso por até 63 dias. Os resultados mostraram que o cultivo repetido por 14 vezes não prejudica a ação protetora da cultura (CE), a qual continua inibindo a colonização cecal por SE. O produto submetido a 12 cultivos e armazenado durante 28 dias em temperatura de refrigeração também continua eficaz.

Intestinal colonization of a human subject by vancomycin-resistant Enterococcus faecium

Objective: To study the ability of two strains of vancomycin-resistant Enterococcus faecium to colonize the human intestine. Methods: A single human subject ingested separately two strains of vancomycin-resistant E. faecium isolated from a pig and a chicken. The feces were cultured on selective medium. Prior to ingestion no vancomycin-resistant cocci were present in the feces. Ingestion of 10 4-10 5 CFU resulted in either no colonization or isolation only after enrichment. Ingestion of 10 7 CFU of one strain resulted in colonization for a period of nearly 3 weeks, with fecal counts at times in excess of 10 6 CFU/g. Ingestion of similar numbers of the other strain and reingestion of the first strain resulted in excretion in the feces for much shorter periods. When the fecal count of the ingested strains was greater than 10 4-10 5 CFU/g, the strains were isolated from swabs taken from perianal skin. Conclusions: Vancomycin-resistant E. faecium strains from pigs and poultry a re able to colonize the human gut and the perianal skin.