Canine Health Research Articles

Fungal diversity and drug susceptibility of the oral mycobiome of domestic dogs.

The purpose of this study was to characterize the variety and diversity of the oral mycobiome of domestic dogs and to identify the commensal and potentially pathogenic fungi present. Two hundred fifty-one buccal swabs from domestic dogs were obtained and struck onto a chromogenic fungal growth medium that distinguishes between fungal species based on colony color and morphology. After isolating and harvesting single colonies, genomic DNA was extracted from pure cultures. PCR was used to amplify a fungal-specific variable rDNA region of the genome, which was then sent for sequencing. Sequencing results were input into the NCBI BLAST database to identify individual components of the oral mycobiome of tested dogs. Of the 251 dogs swabbed, 73 had cultivable fungi present and 10 dogs had multiple fungal species isolated. Although the dogs did not show signs of oral infections at the time, we did find fungal species that cause pathogenicity in animals and humans. Among fungal isolates, Malassezia pachydermatis and species from the genus Candida were predominant. Following fungal isolate identification, antifungal drug susceptibility tests were performed on each isolate toward the medically important antifungal drugs including fluconazole, ketoconazole, and terbinafine. Drug susceptibility test results indicated that a large number of isolates had high MIC values for all three drugs. Exploring the oral mycobiome of dogs, as well as the corresponding drug susceptibility profiles, can have important implications for canine dental hygiene, health, and medical treatment. Identifying the microorganisms within the canine mouth can illustrate a common pathway for fungal pathogens of One Health concern to spread from our canine companions to humans.

Grape seed proanthocyanidin improves intestinal inflammation in canine through regulating gut microbiota and bile acid compositions.

Although certain progress has been made in treating canine inflammatory bowel disease (IBD), a large proportion of dogs have a poor prognosis and may develop resistance and side effects. Therefore, it is of great significance to prevent or alleviate canine IBD through nutritional intervention. Plant polyphenol can interact with intestinal bacteria and has important prospects in the intestinal health improvement. This study evaluated the effect of grape seed proanthocyanidin (GSP), a plant-derived natural polyphenol, on Labrador Retrievers with mild IBD. In Experiment 1 of this study, GSP alleviated persistent intestinal inflammation in canines by improving inflammatory indexes and reducing intestinal permeability. Moreover, GSP treatment increased the abundance of bacteria with potential anti-inflammatory properties and engaging bile acid metabolism, including Ruminococcaceae, Faecalibacterium, Ruminococcus_torques_group, and Lachnospiraceae_NK4A136_group. Notably, targeted metabolomic analysis identified elevated productions of fecal chenodeoxycholic acid and its microbial transformation product lithocholic acid, which might contribute to relieving canine intestinal inflammation. Further, in Experiment 2, fecal microbiota transplantation was used to determine whether gut microbiota is a potential mechanism for GSP efficacy. Dogs with mild IBD received the fecal microbiota from the group administered GSP and mirrored the improvement effects of GSP, which results verified that gut microbial alteration could be an underlying mechanism for GSP efficiency on canine IBD. Our findings highlight that the mechanism of the GSP function on canine IBD is mediated by altering gut microbial composition and improving bile acid metabolism. This study proposes a natural polyphenol-based dietary strategy for improving canine intestinal health.

PSVIII-13 Evaluating the Effects of a Dried brewer’s Yeast Product on the Fecal Characteristics, Metabolites, and Microbiota Populations of Adult Dogs

Abstract Inclusion of brewer’s yeast in pet foods has become popular because of the potential health benefits it provides. However, more research is needed to evaluate the effects of different brewer’s yeast products on canine gut health outcomes. This study aimed to investigate the effects of a brewer’s yeast product on the fecal characteristics, metabolites, and microbiota populations of adult dogs. Sixteen healthy adult dogs (BW: 9.0 ± 1.7 kg) were acclimated for 7 days and then randomly assigned to a control diet containing no yeast or a brewer’s yeast-containing diet (n = 8/group) for a 21-day period. Fresh fecal samples were collected before and after treatment for measurement of fecal scores, pH, dry matter content, metabolite concentrations [short-chain fatty acids (SCFA), branched-chain fatty acids (BCFA), ammonia, phenols, indoles], and microbiota populations. All data were analyzed as a percent change from baseline using the PROC MIXED procedure of SAS, with treatment as the main effect and dog as a random effect. Significance was declared at P ≤ 0.05, and trends reported if 0.05 < P ≤ 0.10. The brewer’s yeast treatment tended to increase (P = 0.10) fecal butyrate concentrations more than that of controls, but fecal characteristics (pH; dry matter; fecal scores) and other metabolite concentrations were not affected by treatment. Fecal bacterial alpha diversity metrics were not affected by treatment, but beta diversity analysis (unweighted UniFrac distances) tended (P = 0.09) to show a shift between treatments. Change in relative abundance of fecal Blautia was less (P = 0.05) in dogs fed brewer’s yeast than controls, but other bacterial genera were unaffected by diet. In conclusion, this study suggests that the dried brewer's yeast products tested had little impact on fecal characteristics, metabolites, or microbiota populations of adult dogs. The tendency of greater fecal butyrate concentrations in dogs fed brewer’s yeast is encouraging, but further research is needed to identify the potential health benefits of these products in canine diets.

Year-round efficacy of a single treatment of fluralaner injectable suspension (Bravecto Quantum™) against repeated infestations with Rhipicephalus sanguineus (sensu lato) and Ctenocephalides felis in dogs

BackgroundPoor owner compliance with monthly control measures means that dogs in Australia can remain susceptible to infestations with fleas, present throughout the whole year, and brown dog ticks, which thrive in tropical and subtropical areas. A 150 mg/ml injectable fluralaner suspension (Bravecto Quantum™) was developed to help ensure year-round protection against these parasites. A study investigated the persistent efficacy of this formulation against repeated challenges with Rhipicephalus sanguineus (sensu lato) and Ctenocephalides felis throughout 12 months following a single subcutaneous treatment.MethodsTwenty dogs were blocked by pre-treatment R. sanguineus s.l. counts and randomized to an untreated control group or to a group treated once, on day 0, with the fluralaner injection (15 mg/kg). Infestations of 50 mixed-sex, unfed adult R. sanguineus s.l. and up to 100 C. felis were done on days 7, 14, 35, 63, 91, 126, 154, 182, 210, 245, 273, 301, 336 and 365. Live flea and tick counts were completed 48 h post-infestation. Flea infestations were also done on day −1, with counts on day 2. Infestations were considered adequate if at each evaluation, at least six dogs in the control group retained at least 20% of tick challenges and 25% of flea challenges.ResultsThe fluralaner injectable suspension was well tolerated. Efficacy against existing flea infestations was > 99% (arithmetic and geometric means) at 48 h post-treatment. At all subsequent assessments throughout the year following treatment, efficacy against fleas remained at 100%. Arithmetic mean tick count reductions relative to the control group ranged from 97.6% to 100% from day 7 through 11 months and was 92.6% at 12 months (geometric means 95.2% to 100% through 12 months).ConclusionThe injectable fluralaner suspension was effective against fleas and brown dog ticks for 12 months following a single treatment. Compared with more frequently administered products where compliance may be suboptimal, the year-round efficacy of this veterinarian-administered fluralaner formulation has the potential to improve owner compliance for control of fleas and ticks. In turn, by reducing the detrimental effects of flea and tick infestations and risk of transmission of flea- and tick-borne pathogens, canine health can be enhanced.Graphical

Development and Validation of a Canine Health-Related Quality of Life Questionnaire and a Human-Canine Bond Questionnaire for Use in Veterinary Practice.

The use of valid questionnaires to assess dogs' health-related quality of life (HRQoL) in veterinary practice can improve canine health outcomes and communications between veterinarians and caretakers of dogs. The Canine HRQoL Questionnaire (Canine HRQoL-Q) and the Human-Canine Bond Questionnaire (HCBQ) were developed and validated to fulfill this need. A literature review, interviews with veterinarians, and focus groups with caretakers were conducted to generate questionnaire items and develop draft questionnaires, which were piloted with caretakers to establish their content validity. Measurement properties were evaluated using data from a prospective survey study (N = 327). Draft Canine HRQoL-Q and HCBQ measures were developed, including a domain structure, items, recall period, and scale/response options. Refinements were made via iterative cognitive interviews with caretakers. When no additional revisions were indicated and content validity was established, the questionnaires were psychometrically tested. Ceiling effects were observed for all items, and factor analyses indicated that the pre-specified domains are appropriate. Internal consistency was demonstrated for the HCBQ (α = 0.79-0.86) and all but the social functioning domain of the Canine HRQoL-Q (α = 0.60). Test-retest reliability for the Canine HRQoL-Q was generally moderate-to-good (with intraclass correlation coefficients (ICCs) > 0.79). Test-retest reliability for the HCBQ was moderate (ICCs: 0.70-0.79) except for the trust domain (ICC: 0.58). Known-groups validity was demonstrated via significant differences (p < 0.05) in scores for health/bonding groups. Convergent validity was supported (r > 0.40) between all domains and the total scores for both questionnaires. The Canine HRQoL-Q and the HCBQ are valid, reliable measures of canine HRQoL for use in veterinary clinics and appear to measure related but distinct concepts that contribute to canine health and wellness.

Black soldier fly (Hermetia illucens) larvae meal based extruded diets: potential to improve canine oral health

Abstract Black soldier fly larvae (BSFL) meal-based pet food is gaining traction in Europe. In order to unlock the full potential of antimicrobial peptides and fatty acids present in BSFL meal, we evaluated the role of BSFL meal containing pet food in modulating the oral health of dogs. During this study eight female beagle dogs were fed with two iso-nutritive diets in a cross-over design with two periods of 50 days each. These diets were made using defatted BSFL meal or low ash poultry by product (PBP) meal as the main protein source. At the end of the first period, the animals underwent a wash out period of 7 days and the treatments were inverted following this treatment. Oral health of dogs was measured by: (1) count of colony forming unit of volatile sulfur producing bacterial (VSC) in dental plaque; (2) DNA extraction and amplification of 16S rRNA genes from saliva for bacterial profiling; and (3) oral malodor scoring. We found significant reduction of VSC () before and after 50 days of BSFL based pet food consumption. Oral malodor score was not significantly different before and after BSFL based pet food consumption. However, there was a strong tendency for malodor reduction related to BSFL fed groups (). Finally, there was a significant difference () between treatments in the relative abundance of Moraxella, with higher abundance in dog’s saliva when fed BSFL diets. This bacterial group is identified as a marker of oral health. In conclusion, the consumption of BSFL meal-based diets has strong potential to decrease VSC and positively modulates the saliva microbiota, which can suppress the occurrence of halitosis and improve oral health.

Perspectives on functional foods for improvement of canine health and treatment of diseases

Perspectives on functional foods for improvement of canine health and treatment of diseases

Sleep-physiological correlates of brachycephaly in dogs

The shape of the cranium is one of the most notable physical changes induced in domestic dogs through selective breeding and is measured using the cephalic index (CI). High CI (a ratio of skull width to skull length > 60) is characterized by a short muzzle and flat face and is referred to as brachycephaly. Brachycephalic dogs display some potentially harmful changes in neuroanatomy, and there are implications for differences in behavior, as well. The path from anatomy to cognition, however, has not been charted in its entirety. Here, we report that sleep-physiological markers of white-matter loss (high delta power, low frontal spindle frequency, i.e., spindle waves/s), along with a spectral profile for REM (low beta, high delta) associated with low intelligence in humans, are each linked to higher CI values in the dog. Additionally, brachycephalic subjects spent more time sleeping, suggesting that the sleep apnea these breeds usually suffer from increases daytime sleepiness. Within sleep, more time was spent in the REM sleep stage than in non-REM, while REM duration was correlated positively with the number of REM episodes across dogs. It is currently not clear if the patterns of sleep and sleep-stage duration are mainly caused by sleep-impairing troubles in breathing and thermoregulation, present a juvenile-like sleeping profile, or are caused by neuro-psychological conditions secondary to the effects of brachycephaly, e.g., frequent REM episodes are known to appear in human patients with depression. While future studies should more directly address the interplay of anatomy, physiology, and behavior within a single experiment, this represents the first description of how the dynamics of the canine brain covary with CI, as measured in resting companion dogs using a non-invasive sleep EEG methodology. The observations suggest that the neuroanatomical changes accompanying brachycephaly alter neural systems in a way that can be captured in the sleep EEG, thus supporting the utility of the latter in the study of canine brain health and function.

Developing diagnostic tools for canine periodontitis: combining molecular techniques and machine learning models

BackgroundDental plaque microbes play a key role in the development of periodontal disease. Numerous high-throughput sequencing studies have generated understanding of the bacterial species associated with both canine periodontal health and disease. Opportunities therefore exist to utilise these bacterial biomarkers to improve disease diagnosis in conscious-based veterinary oral health checks. Here, we demonstrate that molecular techniques, specifically quantitative polymerase chain reaction (qPCR) can be utilised for the detection of microbial biomarkers associated with canine periodontal health and disease.ResultsOver 40 qPCR assays targeting single microbial species associated with canine periodontal health, gingivitis and early periodontitis were developed and validated. These were used to quantify levels of the respective taxa in canine subgingival plaque samples collected across periodontal health (PD0), gingivitis (PD1) and early periodontitis (PD2). When qPCR outputs were compared to the corresponding high-throughput sequencing data there were strong correlations, including a periodontal health associated taxa, Capnocytophaga sp. COT-339 (rs =0.805), and two periodontal disease associated taxa, Peptostreptococcaceae XI [G-4] sp. COT-019 (rs=0.902) and Clostridiales sp. COT-028 (rs=0.802). The best performing models, from five machine learning approaches applied to the qPCR data for these taxa, estimated 85.7% sensitivity and 27.5% specificity for Capnocytophaga sp. COT-339, 74.3% sensitivity and 67.5% specificity for Peptostreptococcaceae XI [G-4] sp. COT-019, and 60.0% sensitivity and 80.0% specificity for Clostridiales sp. COT-028.ConclusionsA qPCR-based approach is an accurate, sensitive, and cost-effective method for detection of microbial biomarkers associated with periodontal health and disease. Taken together, the correlation between qPCR and high-throughput sequencing outputs, and early accuracy insights, indicate the strategy offers a prospective route to the development of diagnostic tools for canine periodontal disease.

Dogs are reservoir hosts of the zoonotic Dirofilaria sp. ‘hongkongensis’ and potentially of Brugia sp. Sri Lanka genotype in Sri Lanka

In 2016, the World Health Organization declared Sri Lanka as having successfully eliminated lymphatic filariasis as a public health concern. However, in recent decades, several infections with subperiodic filarial species suggestive of zoonotic infections have been recorded across the country. The arthropod-borne filarioids Dirofilaria repens, Brugia malayi, Brugia ceylonensis, and Acanthocheilonema reconditum are historically known to be endemic in dogs in Sri Lanka. Despite this, limited information on the prevalence, diversity, and predictors of filarial infections in dogs in the country has resulted in suboptimal control and prevention of these parasites, some of which are known to be zoonotic. To address this, whole blood and metadata were collected and analysed from 423 pet dogs across three geo-climatic zones within Sri Lanka. Blood samples were screened using the Modified Knott's Test (MKT) and PCR followed by Sanger sequencing. Multivariable logistic regression models were used to assess predictors for canine filarial infections. Dirofilaria sp. ‘hongkongensis’ (Dirofilaria sp. HK) and Brugia sp. Sri Lanka (SL) genotype were identified infecting dogs. The overall prevalence of filarial infection in pet dogs by PCR was 36.9% (95% CI 32.3–41.7%, n = 156), compared to 18.8% (95% CI 15.2–22.9%, n = 79) detected using the MKT. >80% of filarial-positive dogs were infected by Dirofilaria sp. HK, while the remaining dogs were infected by Brugia sp. SL genotype. Increasing age (p < 0.001) and residing in the low-country wet zone (p < 0.001), which includes regions that were endemic for human filariasis in Sri Lanka, were associated with filarial infections in dogs. No clear pathognomonic signs for filarial infection were identified, indicating that dogs act as reservoirs for these potentially zoonotic pathogens. Given the morphological similarity of Dirofilaria HK and Brugia sp. SL microfilariae with those of D. repens and B. malayi, respectively, it is likely that these species have been misidentified in the past. Prevention and control measures of these potentially zoonotic canine filarial infections are highly advocated to safeguard both canine and human health.

Impacts to canine dermal microbiota associated with repeated bathing.

Working dogs routinely operate in environmental conditions which may necessitate daily bathing to remove contaminants or soilage. The impacts of frequent or repeated bathing on the canine dermal microbiota are unknown. The objective of this study was to characterize changes in canine dermal microbial populations following repeated daily bathing. Labrador retrievers (n = 16) were bathed daily using a dilute dish detergent solution (1.6% detergent solution) over the course of 14 days. Dermal microbial DNA was collected via sterile swabs (n = 142) taken at days 0, 7, 14, 16, 21, 28, 35, 42, and 49 and analyzed for alpha diversity, beta diversity and relative abundance to assess changes in the dermal microbiota via 16 s sequencing. Results indicate that daily bathing significantly increased Shannon diversity, Chao1, and several rare amplicon sequence variants. Although typically reported in highest abundance, relative abundance was decreased in the phyla Actinobacteria, Firmicutes, and Proteobacteria (p < 0.05). Repeated daily bathing with dilute dish detergent significantly reduced normal healthy dermal microbial taxa and created significant changes in the dermal microbiota of canines. Disruption to the canine dermal microbiota may cause negative impacts to canine dermal health and require further investigation.

Effects of Oligosaccharide Fermentation on Canine Gut Microbiota and Fermentation Metabolites in an In Vitro Fecal Fermentation Model

Owing to the well-established application of prebiotics in human food products, there is a growing interest in their potential as dietary supplements for gut microbiota composition and improvement of the digestive health of dogs. However, targeted studies with dogs as research subjects are still limited. In the present study, an in vitro simulated gut microbiota fermentation system using canine feces from a healthy Border Collie breed was used to investigate the prebiotic effects of five different oligosaccharides and compare their regulatory effects on the gut microbiota structure and the resultant metabolites. Due to the addition of oligosaccharides, the fermented samples had lower pH and higher bacterial proliferation. The oligosaccharide-fermentation selectively boosted Lactobacillus spp., Streptococcus spp., Enterococcus spp., Bacteroides spp., and hindered Escherichia-Shigella spp., Paeniclostridium, spp., and Bacteroides spp. Each oligosaccharide showed distinct characteristics and preferences for regulating gut microbiota structure and abundance. Furthermore, the addition of oligosaccharides increased the production of short-chain fatty acids, particularly butyric acid. This study provides a preliminary basis for the rapid and rational selection of prebiotic oligosaccharides as canine dietary supplements and further explores the function of oligosaccharides and their combinations in canine health.

Biocidal effects of a wipe-down procedure using common veterinary cleansers on microbial burden within working canine exterior coats.

Recent work demonstrating reduction of aerosolized contamination via a wipe-down procedure using common veterinary antiseptics offers promise regarding health concerns associated with cross-contamination from working canines to humans. While mechanical reduction can be achieved via a wipe-down procedure, the biocidal impact on flora within the exterior coat is unknown. This study assessed the biocidal impact of antiseptics on the exterior bacterial community of the canine. Lint-free towels were saturated with 2% chlorhexidine gluconate scrub, or 7.5% povidone-iodine scrub diluted at a 1:4 ratio. Treatments were rotated across the dorsal aspect of kennel housed Foxhounds (n = 30). Sterile swabs were collected in triplicate prior to, and following wipe down, stored in Amies solution at 4°C, plated onto nutrient agar and reduction in colony forming units (CFU) was measured across both treatments. Statistical analysis utilizing PROC GLM examined effects of treatment (p ≤ 0.05). Molecular analysis of the 16S rRNA gene was completed for 3 hounds. Reduction in CFU was measured (p < 0.001) for both antiseptics. Qualitative molecular data indicated that both antiseptics had a biocidal effect on the dominant microbial community on the exterior coat with gram-positive, spore-forming taxa predominating post-treatment. Effective wipe-down strategies using common veterinary cleansers should be further investigated and incorporated to safeguard working canine health and prevent cross-contamination of human personnel.

Multiple anthelmintic drug resistant Ancylostoma caninum in foxhounds

Ancylostoma caninum is the most common and important gastrointestinal nematode of dogs in the United States. Despite recent reports of A. caninum isolates resistant to all classes of anthelmintics, little is known about the frequency and extent of this anthelmintic resistance. The study aim was to evaluate the efficacy of three commercial anthelmintic products in the treatment of foxhound dogs with a history of persistent A. caninum infections. In the first phase of this study, 35 foxhounds were randomly divided into three treatment groups: moxidectin/imidacloprid (MI), pyrantel pamoate/febantel/praziquantel (PFP), and emodepside/praziquantel (EP). Fecal samples were collected on day 0, 11, and 33 post-treatment (PT), and hookworm eggs were quantified using the mini-FLOTAC technique with a multiplication factor of 5 eggs per gram (EPG). The fecal egg count reduction (FECR) on day 11 PT was 65% (95% CI: 62%–68%) for MI, 69% (95% CI: 66%–72%) for PFP, and 96% (95% CI: 94%–97%) for EP. On day 33 PT, the FEC in the MI and PFP groups returned to almost the same values as on day 0, while in the EP group, the FEC remained low. Since MI and PFP proved ineffective, 32 animals were randomly divided into two groups in the second phase. They were treated either with a combination of MI/PFP or EP. The FECR at day 13 PT for the combination MI/PFP was 89% (95% CI: 87%–91%) and 99% (95% CI: 98%–99%) for EP. These results suggest that this A. caninum population is resistant to multiple anthelmintics. Although the combination of MI/PFP improved the anthelmintic efficacy, the FECR remained below 90%. Future studies are indicated to evaluate further the epidemiology of persistent hookworm infections in dogs in the US and to identify more effective treatment protocols as they pose a significant health risk to canine and human health.

An update on mobility assessment of dogs with musculoskeletal disease.

Mobility impairments associated with musculoskeletal diseases, such as osteoarthritis and degenerative joint disease, affect approximately 200,000 dogs annually and pose a notable challenge to canine health and welfare. Osteoarthritis causes the remodelling of synovial joints, alongside inflammation and impaired mechanical function which can be extremely debilitating. Secondary osteoarthritis commonly affects dogs and can be exacerbated by previous joint abnormalities, such as patellar luxation or cranial cruciate ligament rupture. Although musculoskeletal diseases can affect dogs of any age, the early subtle signs of gait abnormalities are perhaps missed by owners, thus, dogs may be in the latter stages of osteoarthritis progression when they are presented to veterinarians. Dogs showing subtle signs of gait abnormalities must be presented to veterinary practices for acute diagnosis to prevent long-term deterioration. Musculoskeletal diseases, such as osteoarthritis and degenerative joint disease, are commonly diagnosed via visible radiographic changes. However, veterinarians can use a combination of subjective and objective clinical scoring systems, such as clinical metrology instruments and gait assessment in conjunction with radiography to aid their diagnosis and longitudinal monitoring of musculoskeletal diseases. These scoring systems may be more sensitive to earlier signs of mobility impairments in dogs, ultimately, promoting increased canine health and welfare by enabling pain reduction, improvement of muscle strength and preservation of joint function. Current canine mobility scoring systems available to veterinarians will be discussed in turn throughout this review for implementation into clinical practice.

Isolation, Characterization, and Comparative Genomics of the Novel Potential Probiotics from Canine Feces.

Lactic acid bacteria (LAB) are commonly used as probiotics; however, not all LAB strains have the same beneficial effects. To successfully use LAB as probiotics in canines, LAB species should originate from the canine intestinal tract as they display host specificity. The objective of this study was to investigate the phenotypic and genomic traits of potential probiotic LAB isolated from canine fecal samples. Twenty LAB samples were evaluated for their potential probiotic characteristics including resistance to low pH, bile salts, hydrophobicity, auto-aggregation, co-aggregation, adhesion to epithelia or mucosa, and production of inhibitory compounds. Additionally, we evaluated their safety and other beneficial effects on canine health, such as DPPH free radical scavenging, and β-galactosidase. Four strains demonstrated potential probiotic characteristics and were selected: Enterococcus hirae Pom4, Limosilactobacillus fermentum Pom5, Pediococcus pentosaceus Chi8, and Ligilactobacillus animalis FB2. Safety evaluations showed that all strains lacked hemolytic activity, could not produce biogenic amines, and did not carry any pathogenic genes. In addition, L. fermentum Pom5 and P. pentosaceus Chi8 displayed susceptibility to all antibiotics and concordant with the absence of antibiotic resistance genes. Based on their phenotypic and genomic characteristics, L. fermentum Pom5 and P. pentosaceus Chi8 were identified as potential probiotic candidates for canines.

Red Ginseng Dietary Fiber Shows Prebiotic Potential by Modulating Gut Microbiota in Dogs.

Red ginseng, widely used in traditional medicine for various conditions, imparts health benefits mainly by modulating the gut microbiota in humans. Given the similarities in gut microbiota between humans and dogs, red ginseng-derived dietary fiber may have prebiotic potential in dogs; however, its effects on the gut microbiota in dogs remain elusive. This double-blinded, longitudinal study investigated the impact of red ginseng dietary fiber on the gut microbiota and host response in dogs. A total of 40 healthy household dogs were randomly assigned to low-dose (n = 12), high-dose (n = 16), or control (n = 12) groups and fed a normal diet supplemented with red ginseng dietary fiber (3 g/5 kg body weight per day, 8 g/5 kg per day, or no supplement, respectively) for 8 weeks. The gut microbiota of the dogs was analyzed at 4 weeks and 8 weeks using 16S rRNA gene sequencing of fecal samples. Alpha diversity was significantly increased at 8 and 4 weeks in the low-dose and high-dose groups, respectively. Moreover, biomarker analysis showed that short-chain fatty acid producers such as Sarcina and Proteiniclasticum were significantly enriched, while potential pathogens such as Helicobacter were significantly decreased, indicating the increased gut health and pathogen resistance by red ginseng dietary fiber. Microbial network analysis showed that the complexity of microbial interactions was increased by both doses, indicating the increased stability of the gut microbiota. These findings suggest that red ginseng-derived dietary fiber could be used as a prebiotic to modulate gut microbiota and improve gut health in dogs. IMPORTANCE The canine gut microbiota is an attractive model for translational studies, as it responds to dietary interventions similarly to those in humans. Investigating the gut microbiota of household dogs that share the environment with humans can produce highly generalizable and reproducible results owing to their representativeness of the general canine population. This double-blind and longitudinal study investigated the impact of dietary fiber derived from red ginseng on the gut microbiota of household dogs. Red ginseng dietary fiber altered the canine gut microbiota by increasing diversity, enriching short-chain fatty acid-producing microbes, decreasing potential pathogens, and increasing the complexity of microbial interactions. These findings indicate that red ginseng-derived dietary fiber may promote canine gut health by modulating gut microbiota, suggesting the possibility of its use as a potential prebiotic.

Molecular characterisation of the current high prevalence of the new CPV-2c variants in the Southern Vietnamese dogs signifies a widespread in the worldwide dog population.

Canine parvovirus type 2 (CPV-2) is known as the primary etiological agent cause of acute gastroenteritis, myocarditis and death of canids worldwide. In Vietnam, although CPV-2 infection and its outbreaks are the most important risk factors of the canine's health concern, lack of available information about the molecular epidemiology of the CPV-2. In this study, the complete coding sequences of 10 CPV-2 strains collected from dogs vaccinated with CPV-2 vaccination were analysed to better understand the genomic characteristics of the current circulating CPV-2 in Vietnam. Ten CPV-specific PCR-positive rectal swab samples were collected from dogs with acute symptoms of haemorrhagic diarrhoea and vomiting in Vietnam in 2019. The complete coding sequences of these CPV strains were analysed to determine their phylogeny and genetic relationship with other available CPV strains globally. Analysis of the VP2 gene sequences demonstrated that the studied strains belonged to the new CPV-2c variants with the unique mutations at amino acids 5Ala-Gly and 447Iso-Met . Phylogenetic tree analysis indicated that the studied strains share a common evolutionary origin with the current CPV-2c strains circulating in dogs in Asia countries, including China, Thailand, Taiwan and Mongolia, in recent years. Low sequence identity between the studied strains and commercial vaccine strains was observed. This study provides deep insights into the molecular characteristics, genetic diversity, and evolution of circulating CPV-2 strains in Vietnam. We recommend more studies to estimate the effectiveness of the CPV vaccine and the need to continue developing other effective vaccination essential to better control the widespread of these new CPV-2 variants.

Understanding the Role of Therapy Dogs in Human Health Promotion.

Dogs may provide humans with a range of physical, mental and social benefits. Whilst there is growing scientific evidence of benefits to humans, there has been less focus on the impact to canine health, welfare and ethical considerations for the dogs. The importance of animal welfare is increasingly acknowledged, indicating that the Ottawa Charter should be extended to include the welfare of non-human animals supporting the promotion of human health. Therapy dog programmes are delivered across a variety of settings including hospitals, aged care facilities and mental health services, highlighting the important role they play in human health outcomes. Research has shown that that there are biomarkers for stress in humans and other animals engaged in human-animal interactions. This review aims to assess the impact of human-animal interactions on therapy dogs engaged in providing support to human health. While challenging, it is paramount to ensure that, within the framework of One Welfare, the welfare of therapy dogs is included, as it is a key factor for future sustainability. We identified a range of concerns due to the lack of guidelines and standards to protect the wellbeing of the dogs engaged in these programmes. Extension of the Ottawa Charter to include the welfare of non-human animals with leveraging through a One Welfare approach would promote animal and human health beyond current boundaries.

Evaluating immunological outcomes associated with histotripsy treatment in canine osteosarcoma: a comparative human oncology model

Abstract Osteosarcoma (OS), the most commonly occurring primary bone tumor in dogs and humans, has deficient treatment options and dismal survival outcomes. Spontaneously occurring OS in dogs shares numerous similarities with humans and has greater prevalence, allowing the dog to serve as an informative comparative oncology model. The objective of this study was to investigate the non-thermal focused ultrasound technique histotripsy as an innovative treatment option for OS. Histotripsy has the potential to both ablate the primary tumor and stimulate an antitumor immune response to mitigate metastatic disease, the leading cause of death in OS. To investigate the immunological outcomes associated with histotripsy and OS, we delivered histotripsy to client-owned canine OS patients (n=29) and utilized an in-vitro model for cross species comparisons between human, dog, and mouse. Histotripsy ablation led to a significantly greater expression of activation markers CD80 and CD62L on circulating monocytes, at 1- and 5-days post histotripsy (DPH), respectively. We observed a significantly greater production of TGFβ in circulating monocytes at 3 DPH compared to baseline. On an independent patient basis, we observed a greater population of CD5 +CD4 +and CD5 +CD8 +cells within the treated region of the tumor compared to untreated region and changes in genetic signature also indicated immune activation. Across species in-vitro we observed macrophage activation (CD80, CD62L, and CD86), and upregulation of genes associated with immune cell chemotaxis and pro-inflammatory response. Our results indicate that histotripsy ablation leads to immune activation and has strong potential to target both primary OS and metastatic disease. NIH (1R21 EB030182-01), Focused Ultrasound Foundation (PLL7GBVK and FUSF-RAP-823R1), and American Kennel Club (Canine Health Foundation No. 02773)