Diversity of Fecal Indicator Enterococci among Different Hosts: Importance to Water Contamination Source Tracking

Abstract

Enterococcus spp. are common bacteria present in the intestinal tracts of animals and are used as fecal indicators in aquatic environments. On the other hand, enterococci are also known as opportunistic pathogens. Elucidating their composition in the intestinal tracts of domestic animals can assist in estimating the sources of fecal contamination in aquatic environments. However, information on the species and composition of enterococci in animal hosts (except humans) is still lacking. In this study, enterococci were isolated from the feces of cattle, pigs, birds, and humans using selective media. Enterococcal species were identified using mass spectrometry technology, and each host was characterized by diversity and cluster analysis. The most dominant species were E. hirae in cattle, E. faecium in birds, and E. faecalis in pigs and humans. Cattle had the highest alpha diversity, with high interindividual and livestock farm diversity. The dominant enterococcal species in pigs and humans were identical, and cluster analysis showed that the majority of the two hosts’ species clustered together.

Occurrence of Antimicrobial-Resistant Enterococcus spp. in Healthy Chickens Never Exposed to Antimicrobial Agents in Central Italy

“…Enterococcus faecium and E. faecalis were the species most frequently isolated with prevalences of 73.47% and 23.47%, respectively, which is in agreement with a previous study on laying hens from the same geographic area [18]. Other authors identified E. faecium as the most encountered species in poultry [19,20]; conversely, E. faecalis was the most frequently isolated enterococcal species in other investigations [9,[21][22][23][24]. The different findings could be related to the tested samples, because some studies focused on specimens collected from chicks only a few days old, in which E. faecalis is the primary gut host [23,25].…”

Development of Multiplex RT qPCR Assays for Simultaneous Detection and Quantification of Faecal Indicator Bacteria in Bathing Recreational Waters

“…having an undetermined faecal origin and clinical interest ( Figure 2 ; Table S5 ). Moreover, several issues are reported for the molecular identification of intestinal enterococci due to the FIB reference in the BWD [ 15 ] through the Enterococcus genus [ 63 , 64 , 65 , 66 ]. The term intestinal enterococci has largely been interchangeable with enterococci, thus addressing the non-accurate identification of FIB references [ 67 ].…”

Technical specifications for a EU‐wide baseline survey of antimicrobial resistance in bacteria from aquaculture animals

“…It has been suggested that the enterococcal composition is specific to host species, with the dominant species in cattle being E. hirae , E. saccharolyticus and E. mundtii , and the dominant species in pigs and birds being E. faecalis and E. faecium , respectively. In humans, E. faecalis and E. faecium are both present and are therefore the main enterococcal species for which AMR monitoring is relevant from a public health perspective (Tamai & Suzuki, 2023 ), and are therefore, proposed to be addressed in the BLS.…”