title: The microbiome associated with equine periodontitis and oral health.
abstract: Equine periodontal disease is a common and painful condition and its severe form, periodontitis, can lead to tooth loss. Its aetiopathogenesis remains poorly understood despite recent increased awareness of this disorder amongst the veterinary profession. Bacteria have been found to be causative agents of the disease in other species, but current understanding of their role in equine periodontitis is extremely limited. The aim of this study was to use high-throughput sequencing to identify the microbiome associated with equine periodontitis and oral health. Subgingival plaque samples from 24 horses with periodontitis and gingival swabs from 24 orally healthy horses were collected. DNA was extracted from samples, the V3-V4 region of the bacterial 16S rRNA gene amplified by PCR and amplicons sequenced using Illumina MiSeq. Data processing was conducted using USEARCH and QIIME. Diversity analyses were performed with PAST v3.02. Linear discriminant analysis effect size (LEfSe) was used to determine differences between the groups. In total, 1308 OTUs were identified and classified into 356 genera or higher taxa. Microbial profiles at health differed significantly from periodontitis, both in their composition (p < 0.0001, F = 12.24; PERMANOVA) and in microbial diversity (p < 0.001; Mann-Whitney test). Samples from healthy horses were less diverse (1.78, SD 0.74; Shannon diversity index) and were dominated by the genera Gemella and Actinobacillus, while the periodontitis group samples showed higher diversity (3.16, SD 0.98) and were dominated by the genera Prevotella and Veillonella. It is concluded that the microbiomes associated with equine oral health and periodontitis are distinct, with the latter displaying greater microbial diversity.
authors.affiliation: Infection and Immunity Research Group, Dental School, University of Glasgow, 378 Sauchiehall Street, Glasgow, G2 3JZ, UK.
authors.forename: Rebekah
authors.initials: R
authors.lastname: Kennedy
authors.affiliation: Infection and Immunity Research Group, Dental School, University of Glasgow, 378 Sauchiehall Street, Glasgow, G2 3JZ, UK.
authors.forename: David Francis
authors.initials: DF
authors.lastname: Lappin
authors.affiliation: Division of Veterinary Clinical Studies, Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush Veterinary Campus, Roslin, Midlothian, EH25 9RG, UK.
authors.forename: Padraic Martin
authors.initials: PM
authors.lastname: Dixon
authors.affiliation: Department of Preventive Dentistry, Academic Centre for Dentistry Amsterdam, University of Amsterdam and VU University Amsterdam, Gustav Mahlerlaan 3004, 1081 LA, Amsterdam, The Netherlands.
authors.forename: Mark Johannes
authors.initials: MJ
authors.lastname: Buijs
authors.affiliation: Department of Preventive Dentistry, Academic Centre for Dentistry Amsterdam, University of Amsterdam and VU University Amsterdam, Gustav Mahlerlaan 3004, 1081 LA, Amsterdam, The Netherlands.
authors.forename: Egija
authors.initials: E
authors.lastname: Zaura
authors.affiliation: Department of Preventive Dentistry, Academic Centre for Dentistry Amsterdam, University of Amsterdam and VU University Amsterdam, Gustav Mahlerlaan 3004, 1081 LA, Amsterdam, The Netherlands.
authors.forename: Wim
authors.initials: W
authors.lastname: Crielaard
authors.affiliation: Infection and Immunity Research Group, Dental School, University of Glasgow, 378 Sauchiehall Street, Glasgow, G2 3JZ, UK.
authors.forename: Lindsay
authors.initials: L
authors.lastname: O'Donnell
authors.affiliation: School of Veterinary Medicine, University of Glasgow, 464 Bearsden Road, Glasgow, G61 1QH, UK.
authors.forename: David
authors.initials: D
authors.lastname: Bennett
authors.affiliation: Department of Preventive Dentistry, Academic Centre for Dentistry Amsterdam, University of Amsterdam and VU University Amsterdam, Gustav Mahlerlaan 3004, 1081 LA, Amsterdam, The Netherlands.
authors.forename: Bernd Willem
authors.initials: BW
authors.lastname: Brandt
authors.affiliation: Infection and Immunity Research Group, Dental School, University of Glasgow, 378 Sauchiehall Street, Glasgow, G2 3JZ, UK. marcello.riggio@glasgow.ac.uk.
authors.forename: Marcello Pasquale
authors.initials: MP
authors.lastname: Riggio
mesh_terms: D000818:Animals; D001419:Bacteria / Q000145:classification* / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics; D005260:Female; D059014:High-Throughput Nucleotide Sequencing / Q000662:veterinary; D006734:Horse Diseases / Q000382:microbiology*; D006736:Horses; D008297:Male; D064307:Microbiota; D009055:Mouth / Q000382:microbiology*; D009909:Oral Health; D010518:Periodontitis / Q000382:microbiology / Q000662:veterinary*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012606:Scotland
chemical_list: D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S