A microbiome analysis of equine peripheral dental caries using next generation sequencing

Abstract

Summary Background Although, peripheral caries (PC) affects almost half of UK horses, no comprehensive microbiological study has been performed on this disorder. As a high proportion of oral bacteria cannot be conventionally cultured, molecular microbiological techniques such as Next Generation Sequencing are required to examine the complex oral bacteria community. Objectives To identify the microbiota involved in equine PC, including comparing microbiota at the more commonly and severely affected three caudal cheek teeth with the less commonly affected three rostral cheek teeth. Study design and Methods Equine dental plaque samples were collected from the palatal aspects of cheek teeth of 63 horses. DNA was isolated and amplified using PCR, targeting the V4 region of the 16S rRNA gene and Next Generation Sequencing of these gene amplicons was performed. The acquired data were processed and analysed using Mothur and R. Results Streptococcus species was the genus most commonly associated with equine PC, whereas Gemella species was the genus most associated with the control group. In a further analysis where the rostral and caudal cheek teeth were compared with each other and with the control group. Veillonella species was the most commonly associated genus with PC of the rostral cheek teeth, Streptococcus species was the most associated genus with the caudal cheek teeth, and Corynebacterium with the control group. Main limitations Some bacteria can have multiple heterogeneous copies of the 16S rRNA gene, which can affect the estimation of their relative abundance. Conclusions Similar to caries studies in other species, acidogenic and aciduric microorganisms including Streptococcus species were found to be associated with equine peripheral caries.

Oral Microbiota Profile Associates with Sugar Intake and Taste Preference Genes

“…HMT498, and Selenomonas spp. in tooth biofilm samples discriminated caries-affected from caries-free adolescents [48], and support previous experimental findings in vitro [13] and in animals [49]. A direct comparison with the results from Anderson et al 2018 [4] may not be appropriate as they used a different 16S rRNA segment and lower similarity requirement for taxa determination.…”

Exodontia-associated bacteremia in horses characterized by next generation sequencing

“…and Moraxella spp. have also been identi ed in the oral cavity of healthy horses [33]. In another study, Actinobacillus spp.…”

“…Whereas the human oral microbiome (reportedly the most extensively studied human micro ora) has been extensively characterized [36,40], only a few descriptions of the equine oral microbiome have been published [21,33,41,42]. Approximately 600 prevalent bacterial species have been identi ed in the human oral cavity based on bacteriological culturing [36].…”

“…Conventional bacterial culturing is limiting because most oral cavity bacteria are uncultivable [32]. An alternative method, such as 16S rRNA amplicon sequencing allows for identi cation of not only cultivable bacteria but also bacteria that might be present in small numbers or uncultivable via standard techniques [32][33][34][35][36].…”

Exodontia associated bacteremia in horses characterized by next generation sequencing

“…Conventional bacterial culturing is limiting because most oral cavity bacteria are uncultivable 32 . An alternative method, such as 16S rRNA amplicon sequencing allows for identification of not only cultivable bacteria but also bacteria that might be present in small numbers or uncultivable via standard techniques [32][33][34][35][36] .…”