P2-73 Microbial Diversity and Associations between Cattle and Geese Feces and Their Shared Soil Environment

Tuesday, August 2, 2016
America's Center - St. Louis
Derek Foster, North Carolina State University, Raleigh, NC
Megan Jacob, North Carolina State University, Raleigh, NC
Hannah Sylvester, North Carolina State University, Raleigh, NC
Anna Rogers, North Carolina State University, Raleigh, NC
Shivaramu Keelara, North Carolina State University, Raleigh, NC
Paula J. Fedorka Cray, North Carolina State University, Raleigh, NC
Introduction: Understanding the mechanisms of pathogen transmission and the dissemination of antimicrobial resistance genes throughout ecological systems is important to combat emerging antimicrobial resistance.  Migratory birds are known reservoirs for antimicrobial resistant (AR) organisms and frequent cattle pasture operations.  The relatedness between microbiota from migratory birds' feces, soil and the feces from production animals co-mingled in their transient environment over time is lacking.

Purpose: The purpose of this study was to longitudinally follow the prevalence and relatedness of microorganisms throughout an environment shared by dairy cattle and a transient population of Branta canadensis (Canada goose).

Methods: Feces (~5 g) from dairy cattle (closed herd, n = 25, collected by rectal palpation) and Canada geese (n = 22, collected from ground), as well as soil samples (~10 g, n = 20) from a defined pasture plot were collected approximately once per month for one calendar year (n = 11 collections). Standard diagnostic laboratory culture methods were used to isolate Enterococcus, Escherichia coli, and other gram-negative organisms.  Isolates were confirmed using MALDI-TOF mass spectrometry.

Results: Enterococcus species were readily obtained from cattle (n = 223), geese (n = 195), and soil (n = 152) samples.  The predominant species was E. hirae (35%), with E. faecium (25%), E. casseliflavus (18%) and E. faecalis (3%) also recovered.  The distribution of species was similar for all sample types.  Escherichia coli also was frequently recovered from cattle (n = 230), geese (n = 223), and soil (n = 220).  The distribution of additional gram-negative organisms including Citrobacter, Enterobacter, and Acinetobacter species varied, but was more diverse in soil than either cattle or geese feces.  

Significance: The presence of microorganisms of public health importance across all sources suggests the likelihood that the exchange of microbial populations is occurring between migratory geese, associated cattle and their shared soil environment.