Study of microbiocenosis of canine dental biofilms

Abstract

Dental biofilm is a complex microbial community influenced by many exogenous and endogenous factors. Despite long-term studies, its bacterial composition is still not clearly understood. While most of the research on dental biofilms was conducted in humans, much less information is available from companion animals. In this study, we analyzed the composition of canine dental biofilms using both standard cultivation on solid media and amplicon sequencing, and compared the two approaches. The 16S rRNA gene sequences were used to define the bacterial community of canine dental biofilm with both, culture-dependent and culture-independent methods. After DNA extraction from each sample, the V3–V4 region of the 16S rRNA gene was amplified and sequenced via Illumina MiSeq platform. Isolated bacteria were identified using universal primers and Sanger sequencing. Representatives of 18 bacterial genera belonging to 5 phyla were isolated from solid media. Amplicon sequencing largely expanded this information identifying in total 284 operational taxonomic units belonging to 10 bacterial phyla. Amplicon sequencing revealed much higher diversity of bacteria in the canine dental biofilms, when compared to standard cultivation approach. In contrast, cultured representatives of several bacterial families were not identified by amplicon sequencing.

Isolation of Oral Bacteria, Measurement of the C-Reactive Protein, and Blood Clinical Parameters in Dogs with Oral Tumor

“…Oral anaerobic bacteria such as Porphyromonas spp., Fusobacterium spp., Bacteriodes spp., Capnocytophaga spp., Prevotella spp., Tannerella spp., Treponema spp., and Actinomyces spp. reported in the previous study [ 29 , 31 , 48 , 70 , 77 , 79 , 80 ] were not found in our study. Some bacterial isolates have been detected from the environment, as the channel of a dog's mouth is exposed to the outdoor environment.…”

“…Ruparella et al and team reported that saliva exhibited the lowest bacterial diversity, the buccal and the tongue dorsum mucosa had the most similar bacteria [ 33 ]. Moreover, the teeth area and the dental plaque were the selected area for the periodontal disease [ 31 , 32 , 67 , 70 , 76 – 78 ]. So, the oral swab sample from the tongue's dorsum mucosa and the mucosa of the hard palate of each dog was taken to compare the microbes among the three groups of dogs in our study.…”

“…According to our study, the bacteria from the supragingival plaque that is related to the periodontitis might not interfere with the results of bacterial isolates in our samples. Many oral bacteria are slow growing, require complex culture media, and specific atmospheric requirements [ 69 , 70 , 79 ]. However, many bacterial species could not be cultured in this study because they are difficult to reproduce under laboratory conditions.…”

“…Nowadays, the modern PCR, automated DNA sequencing, and work on 16S rDNA sequencing bacteria can make an accurate identifcation of bacterial isolates. From this point, the accurate identifcation is one of the most important functions of clinical microbiology laboratories and solves the problem related to the traditional method [66,[68][69][70].…”

Microbial Complexity of Oral Cavity of Healthy Dogs Identified by Mass Spectrometry and Next-Generation Sequencing

“…Moraxella sp., Campylobacter sp., and Corynebacterium sp. identified in dogs sampled have also been previously identified by amplicon sequencing in the oral cavities of dogs [39] and in human wound secretions secondary to canine bites [31,40], reinforcing the complexity of opportunistic pathogens that can be harbored by the oral cavity of these companion animals.…”