Title: Characterization of Enterobacter Spp. Isolated from Shell Eggs Using Pulsed-Field Gel Electrophoresis Authors
|Brito, Jose - EMBRAPA|
|Gilbreth, Stephanie - ECOLAB RESEARCH CENTER|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: February 13, 2006
Publication Date: August 13, 2006
Citation: Brito, J.R., Gilbreth, S.E., Musgrove, M.T., Call, J.E., Luchansky, J.B. 2006. Characterization of enterobacter spp. isolated from shell eggs using pulsed-field gel electrophoresis. [Abstract] International Association of Food Protection's Annual Meeting P-238 pg. 126. Technical Abstract: The prevalence of Enterobacter associated with shell eggs was determined previously to assess the sanitation practices of three commercial facilities in Georgia. Enterobacter were recovered from 117 of 837 (13.97%) samples tested. In the present study we established the relatedness of the 176 isolates (1-5 isolates per positive sample) recovered from 96 of these 117 positive samples. Pulsed-field fingerprinting generated 121 XbaI pulsotypes (34-96% related) distributed as follows: Enterobacter cloacae (104 isolates; 73 pulsotypes, 39-100% related); E. amnigenus (32 isolates; 25 pulsotypes, 33-100% related); E. sakazakii (27 isolates; 12 pulsotypes, 33-100% related); and E. taylorae (9 isolates; 7 pulsotypes, 38-100% related). There was no predominate or persistent pulsotype among isolates from a given plant for any of the 3 visits; the 101 plant X isolates displayed 73 pulsotypes, the 14 plant Y isolates displayed 8 pulsotypes, and the 61 plant Z isolates displayed 41 pulsotypes. Multiple isolates were recovered from 47 of the 96 (49%) positive samples and multiple pulsotypes were displayed by isolates from 34 of these 47 samples (72%). For the majority of visits to each plant, more Enterobacter isolates/pulsotypes were recovered before washing/processing than during or after washing. Pulsed-field fingerprinting of isolates from all three stages indicated that processing was effective at reducing the prevalence and types of Enterobacter, raising the possibility of multiple sources of contamination. These data establish that new/unique isolates of Enterobacter are introduced into the shell egg environment with each batch of eggs and that there is considerable heterogeneity among isolates and species associated with shell eggs. Also, examination of multiple Enterobacter isolates from positive samples is necessary to determine the variety of potential contaminants of egg shells during cleaning.