The subgingival microbial community of feline periodontitis and gingivostomatitis: characterization and comparison between diseased and healthy cats

The Oral Microbiome across Oral Sites in Cats with Chronic Gingivostomatitis, Periodontal Disease, and Tooth Resorption Compared with Healthy Cats

Feline chronic gingivostomatitis (FCGS) is a chronic mucosal and gingival inflammatory disease in which pathogenesis remains unclear. Interactions between the host inflammatory process, the host immune response, and the oral microbiome are implicated in this pathogenesis. To begin to understand this disease and the impact of the microbiome to host inflammatory disease states, we collected sterile noninvasive plaque biofilm samples from ten distinct sites within the oral cavity in cats with stomatitis (n = 12), healthy cats (n = 9), and cats with tooth resorption or periodontitis (n = 11). Analysis of full-length 16S rRNA gene sequences indicated that the microbiomes of cats with FCGS presented marked dysbiosis at multiple oral sites. Additionally, microbiome beta diversity varied with oral condition, indicating that stomatitis, periodontitis, and/or tooth resorption influence the microbiome differently. Lastly, we found that the microbiomes of swabs taken from the oral cavity were comparable to those taken from plaque using endodontic paper points, validating this as another sampling method. Collectively, our work furthers our understanding of the dysbiosis and composition of bacteria in the oral microbiome in FCGS, with hopes of contributing to the prevention, diagnosis, and treatment of this challenging condition in felines.

Transcriptomic signatures of feline chronic gingivostomatitis are influenced by upregulated IL6

Feline chronic gingivostomatitis (FCGS) is a relatively common and debilitating disease characterized by bilateral inflammation and ulceration of the caudal oral mucosa, alveolar and buccal mucosa, and varying degrees of periodontal disease. The etiopathogenesis of FCGS remains unresolved. In this study, we performed bulk RNA-seq molecular profiling of affected tissues derived from a cohort of client-owned cats with FCGS compared to tissues from unaffected animals, to identify candidate genes and pathways that can help guide future exploration of novel clinical solutions. We complemented transcriptomic findings with immunohistochemistry and in situ hybridization assays to better understand the biological significance of the results and performed RNA-seq validation of biologically relevant differentially expressed genes using qPCR assays to demonstrate technical reproducibility. Transcriptomic profiles of oral mucosal tissues in cats with FCGS are enriched with immune- and inflammation-related genes and pathways that appear to be largely influenced by IL6, and include NFKB, JAK/STAT, IL-17 and IFN type I and II signaling, offering new opportunities to develop novel clinical applications based on a more rational understanding of the disease.

Feline chronic gingivostomatitis current concepts in clinical management

PRACTICAL RELEVANCE

Feline chronic gingivostomatitis (FCGS) is a debilitating disease for cats and a challenge for veterinarians and cat caregivers alike. Recent literature indicates that the disease is immune-mediated in nature and likely associated with a chronic viral infection in patients with higher alpha diversity of their subgingival microbiome. The immune-mediated nature of FCGS includes both local as well as systemic effects, and the transcriptomic analysis of affected patients supports these findings.

TREATMENT OPTIONS

Localized therapy in the form of surgical extraction of all, or nearly all, teeth continues to be the mainstay of treatment. For cats that do not respond to surgical management, medical management, in the form of immunosuppressive or immunomodulatory therapy, remains an option. Analgesia is of fundamental importance. Immunomodulation utilizing mesenchymal stromal cell therapy provides an alternative treatment avenue for refractory patients and likely targets the chronic viral infection present in this disease. The potential for treatment stratification and use of novel systemic treatment options may be revealed as the molecular pathways involved in this disease are better described.

AIMS

This review outlines current and emerging concepts linking available science pertaining to FCGS and clinical management of the disease.

EVIDENCE BASE

The article draws on the best evidence base at this juncture and is also driven by the authors' collective experience of working on the disease for over a decade.

Influence of Gallic Acid-Containing Mouth Spray on Dental Health and Oral Microbiota of Healthy Dogs: A Pilot Study

The pilot study aimed to investigate the effects of GAMS on oral microbiota in healthy dog subjects. Thirty-eight dogs were recruited and randomly allocated to the placebo (n = 19) and treatment groups (n = 19). The dogs were treated with mouth spray once daily for 42 days. The changes in the gingival index (GI), plaque index (PI), and calculus index (CI) were measured at baseline (day 0) and end of the study (42nd day). The changes in the oral microbial composition of representative dogs (placebo, n = 7; and treatment, n = 7) were also evaluated at baseline and end of the study. Oral microbial composition was assessed by sequencing. The sequences were annotated using the QIIME 2.0^TM. The GI, PI, and CI indexes were reduced after the GAMS usage. The abundance of the commensal bacterial phylum Actinobacteria and Chloroflexi, genera Frederiksenia, and Bergeyella was improved after six weeks of GAMS usage. GAMS reduced the pathogenic bacterial species, including Neisseria sp., Desulfobulbus sp., Capnocytophaga canis, and Corynebacterium mustelae. Moreover, some pathogenic bacterial abundances were increased at the end of the study. All the microbial variations were observed within the group. The inter-group analysis revealed that the changes were unrelated to GAMS usage. Further studies need to be carried out using more experimental subjects to confirm the effectiveness of GAMS. More metagenomic data are required to evidence the GMAS impact on the oral microbiome of healthy dogs.

Transcriptomic signatures of feline chronic gingivostomatitis are influenced by upregulated IL6

Feline chronic gingivostomatitis (FCGS) is a relatively common and debilitating disease characterized by bilateral inflammation and ulceration of the caudal oral mucosa, alveolar and buccal mucosa, and varying degrees of periodontal disease. The etiopathogenesis of FCGS remains unresolved. In this study, we performed bulk RNA-seq molecular profiling of affected tissues derived from a cohort of client-owned cats with FCGS compared to tissues from unaffected animals, to identify candidate genes and pathways that can help guide future exploration of novel clinical solutions. We complemented transcriptomic findings with immunohistochemistry and in situ hybridization assays to better understand the biological significance of the results and performed RNA-seq validation of selected differentially expressed genes using qPCR assays to demonstrate technical reproducibility. Transcriptomic profiles of oral mucosal tissues in cats with FCGS are enriched with immune- and inflammation-related genes and pathways that appear to be largely influenced by IL6 , and include NFKB, JAK/STAT, IL-17 and IFN type I and II signaling, offering new opportunities to develop novel clinical applications based on a more rational understanding of the disease.

Presence of zoonotic black-pigmented periodontal pathogens in the oral microbiota of pet and stray cats

Black-pigmented bacteria are one of the neglected species to cause periodontal disease in cats, and they are also zoonotic agents that pose an infection risk to humans. In this study, we aimed to determine the presence of Porphyromonas gingivalis, Porphyromonas gulae and Prevotella nigrescens in the oral microbiota of pet and stray cats. Dental swab samples were taken from 25 pet cats and 25 stray cats with symptoms of periodontal disease and then investigated by multiplex polymerase chain reaction using 16S rRNA species-specific primers. As a result of the multiplex PCR analysis, P. gingivalis 3/25 (12%), P. nigrescens 1/25 (4%), P. gingivalis + P. gulae 7/25 (28%), P. gingivalis + P. nigrescens 1/25 (4%), P. gulae + P. nigrescens 1/25 (4%), and P. gingivalis + P. gulae + P. nigrescens 2/25 (8%) were molecularly typed in the pet cats. In addition, 1/25 (4%) of P. gulae and 21/25 (84%) of P. gingivalis + P. gulae were typed in the stray cats. In 10/25 (40%) pet and 3/25 (12%) stray cat samples, no bacteria were detected by molecular typing. In summary, the results provide strong evidence that black-pigmented zoonotic pathogens are associated with cat periodontal disease.

The association between gingivitis and oral spirochetes in young cats and dogs

Although gingivitis frequently occurs in young cats, spirochetes are often found in the early stages of periodontal disease. This study was conducted to determine the association between gingivitis and oral spirochetes in young cats and dogs. The degree of gingivitis was evaluated in a total of 68 cats and 31 dogs under one year of age, and plaques were collected from each carnassial. To detect spirochetes or Porphyromonas gulae in plaque samples, 16S rRNA gene was amplified by polymerase chain reaction (PCR) using specific primers. All data were analyzed using Fisher's exact probability test and odds ratio (OR) with a 95% confidence interval (95% CI). The prevalence of gingivitis was significantly higher in young cats (92.6%) than in young dogs (45.2%). The positive rate of spirochetes by PCR in gingivitis cases was 85.4% in young cats and 15.4% in young dogs, and the positive rate of P. gulae was 66.7% in young cats and 15.4% in young dogs. Both results were significantly higher in young cats than in young dogs. In young cats, spirochetes were significantly associated with gingivitis (OR = 7.95; 95% CI = 1.17, 53.83; P < 0.05), but P. gulae was not (OR = 2.44; 95% CI = 0.38, 15.66; P = 0.23). These results suggest that spirochetes may be associated with the early stages of periodontal disease in cats.

Clinical, radiographic and histopathologic features of early-onset gingivitis and periodontitis in cats (1997-2022)

OBJECTIVES

This study aimed to characterize the clinical, radiographic and histopathologic features of early-onset gingivitis (EOG) and periodontitis in cats.

METHODS

The medical records database was searched for cats diagnosed with histologically confirmed EOG or periodontitis from 1997 to 2022. Information such as medical history, lifestyle factors, clinical presentation, radiographic and histopathologic features were included for 27 client-owned cats. Response to treatment and long-term follow-up was also recorded.

RESULTS

Moderate-to-severe periodontal disease was radiographically confirmed in 78% (21/27) of cats with moderate-to-severe EOG, compared with the evidence of periodontal disease noted in 30% (8/27) of cases during awake oral examination. Horizontal bone loss, along with missing teeth, were the predominant radiographic features noted in 89% (24/27) of cases. The predominant histopathologic feature was moderate-to-severe, erosive-to-ulcerative, neutrophilic and lymphoplasmacytic inflammation with varying degrees of epithelial and stromal hyperplasia. Two cats developed feline chronic gingivostomatitis (FCGS)-like lesions, and seven cats exhibited worsening of aggressive periodontitis (AP). Lack of improvement in the severity of gingivitis or clinical signs evident at the first follow-up appointment was significantly associated with progression of disease (P = 0.004).

CONCLUSIONS AND RELEVANCE

The results of this study demonstrate the importance of oral evaluations in cats as early as 6 months of age. For cats exhibiting substantial gingivitis, an anesthetized evaluation, periodontal treatment and long-term monitoring are recommended. Given the high frequency of moderate-to-severe periodontitis encountered in these cats, clients should be informed about the potential need for tooth extractions. EOG may progress to AP. Finally, this study suggests that there could be a link between EOG and FCGS; however, further studies are needed to better characterize this condition and establish any potential link between the two entities.

The Kitty Microbiome Project: Defining the Healthy Fecal "Core Microbiome" in Pet Domestic Cats

Here, we present a taxonomically defined fecal microbiome dataset for healthy domestic cats (Felis catus) fed a range of commercial diets. We used this healthy reference dataset to explore how age, diet, and living environment correlate with fecal microbiome composition. Thirty core bacterial genera were identified. Prevotella, Bacteroides, Collinsella, Blautia, and Megasphaera were the most abundant, and Bacteroides, Blautia, Lachnoclostridium, Sutterella, and Ruminococcus gnavus were the most prevalent. While community composition remained relatively stable across different age classes, the number of core taxa present decreased significantly with age. Fecal microbiome composition varied with host diet type. Cats fed kibble had a slightly, but significantly greater number of core taxa compared to cats not fed any kibble. The core microbiomes of cats fed some raw food contained taxa not as highly prevalent or abundant as cats fed diets that included kibble. Living environment also had a large effect on fecal microbiome composition. Cats living in homes differed significantly from those in shelters and had a greater portion of their microbiomes represented by core taxa. Collectively our work reinforces the findings that age, diet, and living environment are important factors to consider when defining a core microbiome in a population.

Influence of Gallic Acid-Containing Mouth Spray on Dental Health and Oral Microbiota of Healthy Cats—A Pilot Study

Simple Summary

Periodontal diseases are common dental issues in cats. Oral care supplements were used to prevent diseases and maintain oral health. Moreover, maintaining a healthy oral microbiome is crucial for oral health. Therefore, we have developed a gallic acid-containing mouth spray and studied its effect on oral microbiota and dental health in healthy cats. The results revealed that the gingival and plaque indexes were improved after 42 days of mouth spray treatment in cats. The mouth spray treatment also reduced the abundance of harmful bacterial load and supported the growth of normal oral microbiota. This preliminary study recommended that the gallic acid-containing mouth spray could be an essential oral product to improve the oral hygiene of the cats.

Abstract

This pilot study aimed to investigate the effects of gallic acid-containing mouth spray on oral microbiota in healthy cat subjects. Forty healthy cats were recruited and randomly allocated to the control (G1; n = 20) and treatment groups (G2; n = 20). The cats were treated with mouth spray twice daily for 42 days. The changes in the gingival index (GI) and plaque index (PI) were measured at baseline (day 0) and end of the study (42nd day). The changes in the oral microbial composition of representative animals (control, n = 9; and treatment, n = 8) were also evaluated at baseline and end of the study. Oral microbial composition was assessed by amplifying the V1–V3 region of the 16S rRNA gene from supragingival dental plaque DNA extracts. The sequences were annotated using the QIIME 2.0. The GI and PI were significantly reduced after 42 days of treatment. The deep sequencing revealed that mouth spray influenced the cats’ oral microbiome and was significantly diverse. About 20 phyla and 59 species were observed after 42 days of mouth spray usage in cats’ oral microbiota. The number of operational taxonomic units (OTUs) of post-treatment samples (PoTS) of G2 was greatly reduced compared to other samples. Further analysis revealed that mouth spray acts substantially against Desulfomicrobium orale, one of the known pathogens in periodontal disease. The mouth spray efficiently reduced the growth of 22 species and uprooted 17 species. Moreover, the mouth spray supported the growth of normal oral microbiota, including Moraxella and Neisseria species. The preliminary study suggested that the gallic acids-containing mouth spray could be an essential oral product to improve the oral hygiene of the cats. Moreover, further studies are needed to confirm the beneficial effect of mouth spray on cats.

Xylitol-Containing Chewing Gum Reduces Cariogenic and Periodontopathic Bacteria in Dental Plaque—Microbiome Investigation

Background

Dental caries and periodontal disease remain the most prevalent oral health problems in the world. Chewing xylitol gum may help reduce the risk of caries and periodontitis for dental health benefits. However, little evidence has shown healthy food estimation by sequencing 16S rDNA in oral microbial communities. This study investigated the clinical effect of xylitol chewing gum on dental plaque accumulation and microbiota composition using the PacBio full-length sequencing platform in 24 young adults (N = 24). The participants were randomly assigned to xylitol chewing gum and control (no chewing gum) groups. Participants in the chewing gum group chewed ten pieces of gum (a total of 6.2 g xylitol/day). Dental plaque from all teeth was collected for weighing, measuring the pH value, and analysis of microbial communities at the beginning (baseline, M0) and end of the 2-week (effect, M1) study period.

Results

The results suggested a 20% reduction in dental plaque accumulation (p &lt; 0.05) among participants chewing xylitol gum for 2 weeks, and the relative abundance of Firmicutes (a type of pathogenic bacteria associated with caries) decreased by 10.26% (p &lt; 0.05) and that of Bacteroidetes and Actinobacteria (two types of pathogenic bacteria associated with periodontitis) decreased by 6.32% (p &lt; 0.001) and 1.66% (p &lt; 0.05), respectively. Moreover, the relative abundance of Fusobacteria was increased by 9.24% (p &lt; 0.001), which has been proven to have a higher proportion in dental plaque of healthy adults. However, the dental plaque pH value stayed in a healthy range for the two groups.

Conclusion

In conclusion, chewing xylitol gum would benefit cariogenic and periodontal bacterial reduction in the oral cavity, which could help to prevent the diseases related to these bacteria.

The bacteriome of the oral cavity in healthy dogs and dogs with periodontal disease

OBJECTIVE

To compare the bacteriome of the oral cavity in healthy dogs and dogs with various stages of periodontal disease.

ANIMALS

Dogs without periodontal disease (n = 12) or with mild (10), moderate (19), or severe (10) periodontal disease.

PROCEDURES

The maxillary arcade of each dog was sampled with a sterile swab, and swabs were submitted for next-generation DNA sequencing targeting the V1-V3 region of the 16S rRNA gene.

RESULTS

714 bacterial species from 177 families were identified. The 3 most frequently found bacterial species were Actinomyces sp (48/51 samples), Porphyromonas cangingivalis (47/51 samples), and a Campylobacter sp (48/51 samples). The most abundant species were P cangingivalis, Porphyromonas gulae, and an undefined Porphyromonas sp. Porphyromonas cangingivalis and Campylobacter sp were part of the core microbiome shared among the 4 groups, and P gulae, which was significantly enriched in dogs with severe periodontal disease, was part of the core microbiome shared between all groups except dogs without periodontal disease. Christensenellaceae sp, Bacteroidales sp, Family XIII sp, Methanobrevibacter oralis, Peptostreptococcus canis, and Tannerella sp formed a unique core microbiome in dogs with severe periodontal disease.

CONCLUSIONS AND CLINICAL RELEVANCE

Results highlighted that in dogs, potential pathogens can be common members of the oral cavity bacteriome in the absence of disease, and changes in the relative abundance of certain members of the bacteriome can be associated with severity of periodontal disease. Future studies may aim to determine whether these changes are the cause or result of periodontal disease or the host immune response.

Occurrence of Antimicrobial Resistance Genes in the Oral Cavity of Cats with Chronic Gingivostomatitis

Simple Summary

Oral disease in cats is a significant concern in the small animal practice setting. The specific cause of this disease is inadequately understood; however, antibiotics are commonly used for the management, although many cats respond poorly to these treatments. Antibiotics have been overused and misused in the context of both human and veterinary medicine. Consequently, many antimicrobial drugs are becoming less effective in treating infections. This study aimed to evaluate the presence of antimicrobial resistance genes in swabs obtained from the mouth of cats. Moreover, the study looked at simultaneous occurrence between these genes and one type of oral fungi. We found that antimicrobial resistance genes are extremely common in both clinically healthy and sick cats. Furthermore, we established that Malassezia (a type of fungi) co-occurs with some resistance genes. The findings are important because antimicrobial resistance genes present in the mouth of cats have the potential to transfer to humans and thereby make certain antibiotics less effective.

Abstract

Feline chronic gingivostomatitis (FCGS) is a severe immune-mediated inflammatory disease with concurrent oral dysbiosis (bacterial and fungal). Broad-spectrum antibiotics are used empirically in FCGS. Still, neither the occurrence of antimicrobial-resistant (AMR) bacteria nor potential patterns of co-occurrence between AMR genes and fungi have been documented in FCGS. This study explored the differential occurrence of AMR genes and the co-occurrence of AMR genes with oral fungal species. Briefly, 14 clinically healthy (CH) cats and 14 cats with FCGS were included. Using a sterile swab, oral tissue surfaces were sampled and submitted for 16S rRNA and ITS-2 next-generation DNA sequencing. Microbial DNA was analyzed using a proprietary curated database targeting AMR genes found in bacterial pathogens. The co-occurrence of AMR genes and fungi was tested using point biserial correlation. A total of 21 and 23 different AMR genes were detected in CH and FCGS cats, respectively. A comparison of AMR-gene frequencies between groups revealed statistically significant differences in the occurrence of genes conferring resistance to aminoglycosides (ant4Ib), beta-lactam (mecA), and macrolides (mphD and mphC). Two AMR genes (mecA and mphD) showed statistically significant co-occurrence with Malassezia restricta. In conclusion, resistance to clinically relevant antibiotics, such as beta-lactams and macrolides, is a significant cause for concern in the context of both feline and human medicine.

Management of Severe Oral Inflammatory Conditions in Dogs and Cats

Severe oral inflammatory disease is not uncommon in the mouths of canine and feline patients. An approach to oral diagnosis is offered. This article discusses a brief review of important points in the oral diagnosis and management of main canine (canine chronic ulcerative stomatitis (CCUS), eosinophilic stomatitis, and Wegener's granulomatosis (WG)) and feline diseases (feline gingivostomatitis/caudal stomatitis, oral eosinophilic lesions, pyogenic granuloma, and autoimmune diseases with oral manifestations), and-whereby possible-information about the current understanding of disease pathogenesis and treatment is offered.

Oral Microbiome in Dogs and Cats: Dysbiosis and the Utility of Antimicrobial Therapy in the Treatment of Periodontal Disease

Advances in gene sequence technology and data analysis have enabled the detection and taxonomic identification of microorganisms in vivo based on their unique RNA or DNA sequences. Standard culture techniques can only detect those organisms that readily grow on artificial media in vitro. Culture-independent technology has been used to provide a more accurate assessment of the richness (total number of species) and diversity (relative abundance of each species) of microorganisms present in a prescribed location. The microbiome has been defined as the genes and genomes of all microbial inhabitants within a defined environment. Microorganisms within a microbiome interact with each other as well as with the host. A microbiome is dynamic and may change over time as conditions within the defined environment become altered. In oral health, neither gingivitis nor periodontitis is present, and the host and microbiome coexist symbiotically without evoking an inflammatory response. The circumstances that cause a shift from immune tolerance to a proinflammatory response remain unknown, and a unified, all-encompassing hypothesis to explain how and why periodontal disease develops has yet to be described. The purpose of this review is to clarify the current understanding of the role played by the oral microbiome in dogs and cats, describe how the microbiome changes in periodontal disease, and offer guidance on the utility of systemic antimicrobial agents in the treatment of periodontitis in companion animals.

Neutrophils Orchestrate the Periodontal Pocket

The subgingival biofilm attached to tooth surfaces triggers and maintains periodontitis. Previously, late-onset periodontitis has been considered a consequence of dysbiosis and a resultant polymicrobial disruption of host homeostasis. However, a multitude of studies did not show "healthy" oral microbiota pattern, but a high diversity depending on culture, diets, regional differences, age, social state etc. These findings relativise the aetiological role of the dysbiosis in periodontitis. Furthermore, many late-onset periodontitis traits cannot be explained by dysbiosis; e.g. age-relatedness, attenuation by anti-ageing therapy, neutrophil hyper-responsiveness, and microbiota shifting by dysregulated immunity, yet point to the crucial role of dysregulated immunity and neutrophils in particular. Furthermore, patients with neutropenia and neutrophil defects inevitably develop early-onset periodontitis. Intra-gingivally injecting lipopolysaccharide (LPS) alone causes an exaggerated neutrophil response sufficient to precipitate experimental periodontitis. Vice versa to the surplus of LPS, the increased neutrophil responsiveness characteristic for late-onset periodontitis can effectuate gingiva damage likewise. The exaggerated neutrophil extracellular trap (NET) response in late-onset periodontitis is blameable for damage of gingival barrier, its penetration by bacteria and pathogen-associated molecular patterns (PAMPs) as well as stimulation of Th17 cells, resulting in further neutrophil activation. This identifies the dysregulated immunity as the main contributor to periodontal disease.

Bacterial communities from vagina of dairy healthy heifers and cows with impaired reproductive performance

Vaginal microenvironment plays a significant role in bovine fertility since its resident microorganisms interact with the host mucosa and constitutes the first barrier against ascending pathogens in the reproductive tract. In this study, the vaginal microbiome of healthy heifers (H) and cows with impaired reproductive performance, metritis complex (MT) or repeat breeders (RB), was assessed using a 16S rRNA gene sequencing approach. Analysis revealed that even though a vaginal microbiological guild (Firmicutes, Bacteroidetes, Proteobacteria, Tenericutes, Fusobacteria and Actinobacteria) was shared among healthy heifers and cows with uterine disease; further analysis at genus level showed significant differences depending on the reproductive health status. The relative abundances of recognized uterine pathogens such as Bacteroidetes, Fusobacterium and Helcococcus were higher in MT when compared with H and RB; therefore, their presence in vagina can be considered as a risk factor for fertility. The present study describes for the first time, the composition of native bacterial communities in the vagina of cows undergoing the repeat breeding syndrome (RBS), and reports an association between this disease and the presence of Porphyromonas and unassigned genera of the Pasteurellaceae family. In addition, this work highlights the bacteria associated with a healthy vagina: genera from the families Lachnospiraceae, Rikenellaceae and the genera Acinetobacter, Bacillus, Oscillospira, CF231 and 5-7NS. Results highlighted herein, signify the potential of the evaluation of the bovine vaginal microbiome to future design therapeutic interventions to improve pregnancy rates however, further research is needed to elucidate the balance of bacterial species resulting in an optimal reproductive health.

A Case Series Analysis of Dental Extractions' Outcome in Cats with Chronic Gingivostomatitis Carrying Retroviral Disease

Simple Summary

Feline chronic gingivostomatitis (FCGS) is a chronic, painful, oral inflammatory disease, which can be associated with retroviral disease comorbidity’s, namely feline immunodeficiency virus (FIV) and feline leukaemia virus (FeLV). A total 111 case series of cats affected by this oral disease, treated with dental extractions, were analyzed retrospectively, considering if they carried or not one of these retroviral diseases. Cats with lingual ulcers, independently from their retroviral status, were 2.7 times more prone to have a worse response to dental extractions than cats without lingual ulcers. When compared with cats without retroviral disease, FeLV-positive cats presented less proliferative lesions and tended to have more lingual ulcers. Furthermore, these cats had a significantly worse outcome, with 7.5 times more chances of having no improvement.

Abstract

This study aims to evaluate and compare the clinical outcome after dental extractions of cats with FCGS infected with feline immunodeficiency virus (FIV) and feline leukaemia virus (FeLV). A retrospective case series included cats with diagnosis of FCGS, availability of detailed clinical records, full-mouth dental radiographs, and retroviral disease test results. Effectiveness of surgical treatment (EOT) was registered. Three groups were defined: control, FIV and FeLV. In this study, 111 cats were included: 60 controls, 29 FIV- and 22 FeLV-positive cats. When compared with control cases, FeLV-positive cats had significantly less proliferative stomatitis lesions, and they tended to have more lingual ulcers. Concurrently, FeLV-positive cats had significantly less tooth resorptive lesions. No other significant differences in FCGS clinical signs were found between groups. FeLV-positive cats had a significantly worse outcome after dental extractions compared to the other groups. In fact, FeLV-positive cats had 7.5 times more chances of having no improvement after dental extractions. This study concludes that the response to dental extractions in FeLV-positive cats is significantly worse, when comparing to cats that do not carry retroviral disease. Therefore, it is important to acknowledge the effect of FeLV status on the prognosis of these cats.

Insights into the Oral Bacterial Microbiota of Sows

The investigation of bacterial microbiota represents a developing research field in veterinary medicine intended to look for correlations between animal health and the balance within bacterial populations. The aim of the present work was to define the bacterial microbiota of the oral cavity of healthy sows, which had not been thoroughly described so far. In total, 22 samples of oral fluid were collected and analyzed by 16S-rRNA gene sequencing. CLC Genomics Workbench 20.0 (QIAGEN Digital Insights, Aarhus, Denmark) was then used to examine the results. The predominant orders were Lactobacillales, Clostridiales, and Corynebacteriales. Lactobacillaceae, Corynebacteriaceae, Moraxellaceae, Aerococcaceae, and Staphylococcaceae were the most represented families. As regards the most abundant genera, Lactobacillus, Corynebacterium, Acinetobacter, Staphylococcus, Rothia, Aerococcus, and Clostridium can be pointed out as the bacterial core microbiota. Sows were also divided into “gestating” and “lactating” groups, and mild differences were found between pregnant and lactating sows. The data herein described represent an original contribution to the knowledge of the porcine bacterial microbiota. Moreover, the choice of sows as experimental animals was strategic for identifying the adult microbial community. These data provide a basis for further studies on the oral bacterial microbiota of pigs.

Characterization of Oral Microbiota in Cats: Novel Insights on the Potential Role of Fungi in Feline Chronic Gingivostomatitis

Previous studies have suggested the involvement of viral and bacterial components in the initiation and progression of feline chronic gingivostomatitis (FCGS), but the role of fungi remains entirely unknown. This pilot study aimed to investigate the bacteriome and mycobiome in feline oral health and disease. Physical exams, including oral health assessment, of privately owned, clinically healthy (CH) cats (n = 14) and cats affected by FCGS (n = 14) were performed. Using a sterile swab, oral tissue surfaces of CH and FCGS cats were sampled and submitted for 16S rRNA and ITS-2 next-generation DNA sequencing. A high number of fungal species (n = 186) was detected, with Malassezia restricta, Malassezia arunalokei, Cladosporium penidielloides/salinae, and Aspergillaceae sp. being significantly enriched in FCGS samples, and Saccharomyces cerevisiae in CH samples. The bacteriome was significantly distinct between groups, and significant inter-kingdom interactions were documented. Bergeyella zoohelcum was identified as a potential biomarker of a healthy feline oral microbiome. These data suggest that fungi might play a role in the etiology and pathogenesis of FCGS, and that oral health should not simply be regarded as the absence of microbial infections. Instead, it may be viewed as the biological interactions between bacterial and fungal populations that coexist to preserve a complex equilibrium in the microenvironment of the mouth. Additional investigations are needed to improve our understanding of the feline oral ecosystem and the potential interactions between viruses, bacteria, and fungi in FCGS.

Differences in the Composition of Cultivable Aerobic and Facultative Anaerobic Oral Microbiota in Cats of Various Age Groups

The feline oral cavity is naturally inhabited by various microorganisms contributing to the maintenance of its oral health. The imbalance of oral microbiota or the presence of pathogenic agents can lead to secondary oral diseases. Various factors such as sex, diet, breed, environment and even age, affect the composition of a healthy oral microbiota during the life of cats. The purpose of this study was to compare the composition of culturable aerobic and facultative anaerobic micro-biota in cats in terms of different age categories. We used conventional cultivation methods in conjunction with microscopic and biochemical methods to isolate and identify the micro organisms found in the oral cavity of cats. The examination of 76 samples confirmed the dominance of the phylum Proteobacteria in almost all groups. Commonly occurring bacteria have been identified, i. e. Streptococcus spp., Neisseria spp. and Pasteurella spp. Although aerobic and facultative anaerobic oral micro biota were examined, differences between age groups were noted. The microbial diversity of the oral microbiota significantly increased with age.

Preliminary functional analysis of the subgingival microbiota of cats with periodontitis and feline chronic gingivostomatitis

The subgingival microbial communities of domestic cats remain incompletely characterized and it is unknown whether their functional profiles are associated with disease. In this study, we used a shotgun metagenomic approach to explore the functional potential of subgingival microbial communities in client-owned cats, comparing findings between periodontally healthy cats and cats with naturally occurring chronic periodontitis, aggressive periodontitis, and feline chronic gingivostomatitis. Subgingival samples were subjected to shotgun sequencing and the metagenomic datasets were analyzed using the MG-RAST metagenomic analysis server and STAMP v2.1.3 (Statistical Analysis of Metagenomic Profiles) software. The microbial composition was also described to better understand the predicted features of the communities. The Respiration category in the level 1 Subsystems database varied significantly among groups. In this category, the abundance of V-Type ATP-synthase and Biogenesis of cytochrome c oxidases were significantly enriched in the diseased and in the healthy groups, respectively. Both features have been previously described in periodontal studies in people and are in consonance with the microbial composition of feline subgingival sites. In addition, the narH (nitrate reductase) gene frequency, identified using the KEGG Orthology database, was significantly increased in the healthy group. The results of this study provide preliminary functional insights of the microbial communities associated with periodontitis in domestic cats and suggest that the ATP-synthase and nitrate-nitrite-NO pathways may represent appropriate targets for the treatment of this common disease.

Stem cell therapy prior to full-mouth tooth extraction lacks substantial clinical efficacy in cats affected by chronic gingivostomatitis

OBJECTIVES

The aim of this pilot study was to determine the safety, efficacy and immunomodulatory function of systemically administered adipose-derived mesenchymal stem cells (ASCs) in cats affected by feline chronic gingivostomatitis (FCGS) prior to full-mouth tooth extractions.

METHODS

Five client-owned cats affected with FCGS that did not undergo full-mouth tooth extractions for FCGS treatment received two intravenous injections of 20 million fresh, allogeneic or autologous ASCs. An oral examination with photographs, a complete blood count, blood immune cell phenotyping and a biochemical profile were completed at 0 and 6 months after treatment.

RESULTS

Four cats completed the study and one cat exited the study 3 months after treatment. While the treatment was determined to be clinically safe, no positive clinical response was observed in three cats and a mild response was noted in two cats. Furthermore, none of the cats exhibited immune modulation, as evidenced by no alteration in circulating CD8⁺ T cells, normalization of the CD4:CD8 ratio or neutrophil counts.

CONCLUSIONS AND RELEVANCE

Unlike the reported efficacy of ASCs in treating cats with non-responsive FCGS after full-mouth tooth extraction, the systemic administration of ASCs prior to full-mouth tooth extraction lacks substantial clinical efficacy and is not recommended at this time.

Influence of the FIV Status and Chronic Gingivitis on Feline Oral Microbiota

Feline chronic gingivostomatitis (FCGS) has an unclear pathogenesis with the oral microbiome and viral infections, such as feline immunodeficiency virus (FIV), thought to contribute. Although the relationship between the FIV status and FCGS is not clear, one theory is FIV-induced immune dysregulation could contribute to oral dysbiosis, promoting FCGS development. To further understand the relationship between FCGS, FIV infection, and the oral microbiome, oral cavities of forty cats fitting within 4 groups (FIV- without gingivitis, FIV+ without gingivitis, FIV- with gingivitis, FIV+ with gingivitis) were swabbed. Next generation sequencing targeting the V4 region of the 16s rRNA gene was performed for bacterial community profiling. No differences in diversity were observed, however, analysis of the data in terms of gingivitis revealed differences in the relative abundance of taxa and predicted functional output. Odoribacter spp., a bacteria associated with oral disease, was found in higher relative abundances in cats with the highest gingivitis grade. Cats with gingivitis were also found to harbor communities more involved in production of short-chain fatty acids, which have been connected with oral disease. Significant findings associated with the FIV status were few and of low impact, suggesting any connection between the FIV status and FCGS is likely not related to the oral microbiota.