Panoramic view of the occurrence of Yersinia species other than Y. pestis in Brazil

Data on the occurrence of Yersinia species. other than Y. pestis in Brazil are presented. Over the past 40 years, 767 Yersinia strains have been identified and typed by the National Reference Center on Yersinia spp. other than Y. pestis, using the classical biochemical tests for species characterization. The strains were further classified into biotypes, serotypes and phagetypes when pertinent. These tests led to the identification of Yersinia cultures belonging to the species Y. enterocolitica, Y.pseudotuberculosis, Y. intermedia, Y. frederiksenii and Y. kristensenii. Six isolates could not be classified in any of the known Yersinia species and for this reason were defined as Non-typable (NT). The bio-sero-phagetypes of these strains were diverse. The following species of Yersinia were not identified among the Brazilian strains by the classical phenotypic or biochemical tests: Y. aldovae, Y. rhodei, Y. mollaretti, Y. bercovieri and Y.ruckeri. The Yersinia strains were isolated from clinical material taken from sick and/or healthy humans and animals, from various types of food and from the environment, by investigators of various Institutions localized in different cities and regions of Brazil.

Numerical taxonomy of vibrio & allied organisms.

Forty four strains of Vibrio, Pasteurella, Yersinia, Aeromonas, Escherichia, Klebsiella and Enterobacter were tested for 44 characters and the overall results scored by the procedure of numerical taxonomy. The strains were clustered by the weighted pair group method with the arithmatic averaging. The V. cholerae 01 and the non-01 V. cholerae being interlinked at a very high level (86% to 97.5%) within a single cluster were considered under the same species. V.cholerae having Classic, E1 Tor and Gindha (Pfeiffer 1896, as per priority) biotypes respectively. The biotypes of V.parahaemolyticus remained clearly delineated from Vibrio and Aeromonas, and, belonged to a new separate genus. The V. parahaemolyticus biotypes were located more adjacent to Yersinia and Pasteurella than the V. cholerae cluster. V.fluvialis 1 appears as a biotype of V.parahaemolyticus, and, not a new species.

Investigación de bacterias del género Yersinia en pollos destinados al consumo y en alimento balanceado para aves / Bacteria of the genus Yersinia in chickens for human consumption and in balanced bird food

Se ha investigado la presencia de bacterias del género Yersinia en 50 muestras de pollo faenados destinados al consumo y en 65 muestras de alimento balanceado para aves. Se enriquecieron en solución de buffer de fosfatos 0,067 M pH 7,6 en NaCl 0,145 M (PBS) a 4 -C durante 21 días. El post-enriquecimiento se realizó con KOK al 0,5%. Los aislamientos se hicieron sobre agar Salmonella-Shigella (SS) y agar MacConkey (MC). Las colonias sospechosas se sembraron en triple azúcar hierro (TSI). Las colonias se purificaron a través de pruebas bioquímicas, serológicas y de fagotipia. De las muestras de pollo se aisló Y. enterocolítica en un 10% con las siguientes biovar (B), serovar (O) y fagovar (Lis): B:1,0:6,47, Lis Xz; B:1, 0:6, Lis Xz; y B:1,0:5, Lis Xz; Y. intermedia en un 40%, B:1,0:52,Lis Xz y B:1,0:52,53,54,Lis Xz (NRA, nitrato reductasa de tipo A); Y. frederiksenii en un 4%, 0:10, K1,25,35,38,46, Lis Xz (citrato +) y 0:10,K1,25,35,38,46,Lis Xz (ONPG -: citrato +); Y kristensenii en un 2%, no aglutinable, Lis Xo. Del alimento balanceado para aves no se aisló Yersinia spp. todas las cepas fueron negativas a las pruebas de dependencia del calcio para el crecimiento y autoaglutinación a 37 -C indicandola ausencia de plasmidios de virulencia. También fueron negativas a la prueba de Sereny. Cuatro cepas fueron enterotoxina positivas. De los resultados obtendios se concluye que las cepas de Yersinia aisladas a partir de pollos no significan un riesgo para la salud