Abstract
Anseriformes deserve special attention in the epidemiology of Brachyspira spp. because diverse Anseriformes species have been described to act as highly efficient carriers of several Brachyspira spp. that can also infect livestock. The aim of this study was to investigate the prevalence and diversity of Brachyspira spp. in waterfowl that winter in Spain. Brachyspira spp. were isolated from 51 of the 205 faecal samples collected from graylag geese and mallards in the Villafáfila Lagoons Nature Reserve (Northwestern Spain). The Brachyspira species identified through phenotyping, PCR and sequencing of the nox gene were B. pilosicoli (5.9%), B. alvinipulli (11.8%), "B. hampsonii" (19.6%), B. murdochii (23.5%) and B. innocens (39.2%). The most relevant finding of this study is the description of "B. hampsonii" in specimens from birds for the first time. Phylogenetic analysis of the nox gene sequences grouped all of the obtained "B. hampsonii" isolates into a cluster with Brachyspira strains previously identified by others as "B. hampsonii" and separated from other Brachyspira spp. isolates and reference strains. Additionally, this cluster was related to clades that grouped B. murdochii and B. innocens isolates. The identification of “B. hampsonii” was also achieved in 8 of the 10 isolates by sequencing the16S rRNA gene and tlyA gene. Regardless of the species identified, no antimicrobial resistance was observed in any of the enteropathogenic isolates recovered. This is the first description of “B. hampsonii” in European waterfowl, which might represent hosts that serve as natural reservoirs of this Brachyspira species. This finding indicates that this spirochete is not limited to North America, and its presence in wild birds in Europe poses a risk of transmission to livestock.
Highlights
Spirochaetes are frequently present in the gastrointestinal tracts of mammals, including human beings, and some birds
A number of studies have focused on estimation of the prevalence and diversity of intestinal spirochaetes in different bird populations [10,22,23,24,25,26,27] because they could represent important reservoirs of Brachyspira species, including those that can infect and cause disease in livestock
Special attention should be given to the possibility of the transmission of pathogenic Brachyspira spp. to swine because Spain is the second largest pigproducing country in Europe, with an output of more than 41 million pigs per year
Summary
Spirochaetes are frequently present in the gastrointestinal tracts of mammals, including human beings, and some birds. A total of seven species have been assigned to this genus (i.e., B. aalborgi, B. alvinipulli, B. hyodysenteriae, B. innocens, B. intermedia, B. murdochii and B. pilosicoli), and several other species have been officially proposed, they are not yet fully recognised as members of this genus (i.e., ‘‘B. canis’’, “B. suanatina”, “B. rattus”, “B. pulli”, “B. ibaraki”, “B. corvi”, “B. muri” and “B. muridarum”). The pathogenicity of some of these Brachyspira species has not been completely elucidated and their role in the development of intestinal diseases in their hosts remains uncertain, some of these species are unquestionably recognised as livestock enteropathogens. B. pilosicoli causes spirochaetal diarrhoea in swine and has been associated with diarrhoea in a variety of mammalian hosts, such as humans, non-human primates, dogs and horses [2,3,4]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
