2019 AAHA Canine Life Stage Guidelines*

Voxelwise analysis of the central hearing pathway in senior dogs reveals changes associated with fractional lifespan

Presbycusis, or age-related hearing loss, affects both elderly humans and dogs, significantly impairing their social interactions and cognition. In humans, presbycusis involves changes in peripheral and central auditory systems, with central changes potentially occurring independently. While peripheral presbycusis in dogs is well-documented, research on central changes remains limited. Diffusion tensor imaging (DTI) is a useful tool for detecting and quantifying cerebral white matter abnormalities. This study used DTI to explore the central auditory pathway of senior dogs, aiming to enhance our understanding of canine presbycusis. Dogs beyond 75% of their expected lifespan were recruited and screened with brainstem auditory evoked response testing to select dogs without severe peripheral hearing loss. Sixteen dogs meeting the criteria were scanned using a 3 T magnetic resonance scanner. Tract-based spatial statistics was used to analyze the central auditory pathways. A significant negative correlation between fractional lifespan and fractional anisotropy was found in the acoustic radiation, suggesting age-related white matter changes in the central auditory system. These changes, observed in dogs without severe peripheral hearing loss, may contribute to central presbycusis development.

Effect of surgery on oxidative stress and endogenous tocopherol concentrations in juvenile female dogs

BACKGROUND

Surgery such as ovariectomy causes an inflammatory and oxidative stress. This study was designed to evaluate endogenous tocopherol levels in response to surgical oxidative stress induced by abdominal surgery (ovariectomy) in thirty-two juvenile female dogs. The dogs received meloxicam before surgery (0.2 mg/kg SC) and after surgery (0.1 mg/kg OS every 24 h), 0.03 mg/kg of atropine sulfate (IM), and propofol 4 mg/kg intravenously (IV). General anesthesia was maintained with sevoflurane. Physiological, hematological and biochemical parameters, malondialdehyde (MDA) and α-, δ-, γ-tocopherols were evaluated at baseline, 36 and 48 h after surgery.

RESULTS

The physiological parameters remained within normal ranges. Blood glucose concentration increased, while the albumin levels decreased after surgery. Rescue analgesia was not required. MDA levels increased above the baseline at 36 and 48 h after surgery (P < 0.001). The α-, δ-, and γ-tocopherol concentrations decreased from baseline at 36 and 48 h after surgery (P < 0.001).

CONCLUSIONS

Surgery in juvenile female dogs revealed oxidative, increased MDA concentrations, reduced tocopherol levels, and had a clinically insignificant influence on homeostasis.

The role of veterinarians in zoonosis prevention: Advising families of immunocompromised children with pets

Background

Pet ownership is widespread, offering numerous benefits to individuals and families. However, the risk of zoonotic diseases must be carefully considered, especially for immunosuppressed patients. Knowledge gaps in preventive measures for zoonoses have been identified, underscoring the vital role of veterinarians in addressing this issue.

Objectives

This study aimed to assess the knowledge and recommendations of veterinarians regarding pet ownership by immunocompromised individuals. Additionally, we compared these insights with responses from European healthcare professionals specializing in pediatric transplant recipients.

Methods

We conducted an observational, cross-sectional study involving small animal veterinarians in Spain. An online survey was administered to gather information on veterinarians' knowledge of zoonoses and their recommendations for immunocompromised pet owners.

Results

A survey of 514 individuals was collected from experienced veterinarians mainly working in primary care clinics. Surprisingly, 63% of respondents did not routinely inquire about the presence of immunocompromised individuals among pet owners, although 54% offered specific recommendations for this group. Most respondents adhered to deworming guidelines for pets owned by immunocompromised individuals and demonstrated sound practices in Leishmania and Leptospira prevention, as well as the avoidance of raw food. However, gaps were noted concerning Bordetella bronchiseptica vaccination. Notably, veterinarians outperformed medical professionals in their knowledge of zoonotic cases and identification of zoonotic microorganisms. The presence of specific recommendations in veterinary clinics was viewed positively by nearly all respondents.

Conclusions

Our findings indicate that veterinarians possess a superior understanding of zoonotic pathogens and exhibit greater proficiency in diagnosing zoonoses compared with physicians. They stay well-informed about recommendations outlined in established guidelines and are more likely to provide written recommendations in their clinics than physicians. Nevertheless, knowledge gaps among veterinarians emphasize the need for enhanced communication between medical and veterinary professionals. Reinforcing the "One Health" concept is imperative, with veterinarians playing a pivotal role in this collaborative effort.

Effect of Breed on Hematological and Biochemical Parameters of Apparently Healthy Dogs Infected with Zoonotic Pathogens Endemic to the Mediterranean Basin

Dogs are considered the main reservoir of several zoonoses endemic to the Mediterranean Basin. In this study, a prevalence of infections and coinfections of canine vector-borne diseases was analyzed in apparently healthy dogs of different canine pure breeds in Sicily (Italy), where these diseases are endemic. The seroprevalence of Leishmania infantum, Ricketsia ricketsii, Anaplasma phagocytophilum, and Erlichia canis was assessed, as single and coinfections. Biochemical and hematological parameters were evaluated, and epidemiological factors, including sex, age, and canine breed, were recovered. The most frequent infection was L. infantum (45.61%), following R. ricketsii (36.84%), both as single, double, or triple coinfections. Coinfections change the biochemical and hematological parameters of the host, and canine breeds are related to the infection frequency and the parameters observed during infections. Changes in the complete blood count (CBC) and biochemical values also differ between canine breeds, with the Cirneco dell'Etna dogs infected with L. infantum being the animals presenting the most interesting results in our study. High values of RBC, hemoglobin, hematocrit, mean corpuscular hemoglobin (MCH), the albumin/globulin (A/G) ratio, and albumin and low levels of β-2 globulin and γ-globulin were found only in this canine breed, suggesting some resistance to infection in these dogs. Future studies about the immune response of this canine breed could be interesting to determine their possible resistance to zoonotic pathogens, such as L. infantum.

Noninvasive Blood-Based Cancer Detection in Veterinary Medicine

The past decade has seen incredible advances in blood-based cancer detection in people and in dogs - yet this represents only a glimpse of the benefits these tests can provide to patients. The clinical uses of this technology range from screening asymptomatic individuals for early detection to use as an aid in diagnosis when cancer is suspected, to cancer monitoring both during and after treatment. This article summarizes the benefits of early cancer detection and examines use cases and methods of blood-based cancer detection in dogs, including quantitative, qualitative, and alternative approaches.

Cross-sectional United Kingdom surveys demonstrate that owners and veterinary professionals differ in their perceptions of preventive and treatment healthcare needs in ageing dogs

Perceptions of dog owners and veterinary professionals (surgeons/nurses) can influence the preventive healthcare and treatment provided to dogs, especially at the senior life-stage, when chronic diseases become more common. This study compared perceptions of healthcare of dogs as they age between dog owners and veterinary professionals. Data from two online surveys (owners: N = 633, veterinary professionals: N = 305) examined perceived need for veterinary visits and vaccinations. In addition, 48 clinical signs were rated on perceived prevalence (whether owners' dogs had experienced them) and how urgently they should seek veterinary advice. Groups were compared using descriptive statistics and chi-square. Owners most often believed a 'healthy' senior dog (>7 years) should go to the vet once a year (47% owners vs. 25% veterinary professionals, p < 0.001), compared with veterinary professionals every 6 months (39 vs. 73%). A minority (14%) of owners would just take the dog 'if they got sick' but only 2% of veterinary professionals advised this, and 16% of owners of dogs of all ages had not had any contact with their veterinary practise in the previous year. Nearly all veterinary professionals (92%) believed that senior/geriatric dogs should receive yearly vaccinations. However, 28% of owners' dogs of all ages were not vaccinated in the previous year and, of these, 33% did not believe that older dogs need vaccinations. Only 10% of dogs considered 'old' by their owners had attended a senior wellness clinic or examination, despite 14% of practises offering them. The three most common clinical signs reported by owners were slowing down on walks (57%), dental tartar (53%) and being stiff on rising (50%). Owners perceived urgency to seek veterinary care was lower if they had experienced the clinical sign before. In the current study, dog owners and veterinary professionals differed in their opinions about the need for veterinary care, suggesting new educational initiatives, and more effective communication is required.

Clinical validation of circulating immune complexes for use as a diagnostic marker of canine leishmaniosis

Introduction

Canine leishmaniosis (CanL) is a systemic disease that affects dogs. When multiplication of the parasite cannot be controlled, dogs consistently show high levels of antigen and IgG antibodies, which lead to the formation of circulating immune complexes (CIC). Timely intervention to reduce the parasite load and CIC levels is crucial for preventing irreversible organ damage. However, a diagnostic test to quantify CIC levels is currently lacking.

Methods

In this real-world study, we aimed to examine the performance of a new ELISA to measure CIC levels in dogs naturally infected with Leishmania infantum. Thirty-four dogs were treated according to their clinical condition and followed for 360 days. Before (day 0) and after treatment (days 30, 90, 180, 270, and 360), all dogs underwent a physical examination, and blood samples were obtained for CBC, biochemical profile, serum protein electrophoresis and IFAT. Serum PEG-precipitated CIC were determined by ELISA.

Results

Our results indicate higher CIC levels in dogs in advanced disease stages showing higher antibody titres (p < 0.0001, r = 0.735), anemia (p < 0.0001), dysproteinemia (p < 0.0001), and proteinuria (p = 0.004). Importantly, dogs responding well to treatment exhibited declining CIC levels (p < 0.0001), while in poor responders and those experiencing relapses, CIC were consistently elevated. CIC emerged as a robust discriminator of relapse, with an area under the curve (AUC) of 0.808. The optimal cut-off to accurately identify relapse was an optical density of 1.539.

Discussion

Our findings suggest that declining CIC levels should be expected in dogs showing a favorable treatment response. Conversely, in dogs displaying a poor response and recurrent clinical relapses, CIC levels will be high, emphasizing the need for vigilant monitoring. These findings suggest that CIC could serve as a valuable biomarker for disease progression, treatment efficacy, and relapse detection in CanL. Our study contributes to enhancing diagnostic approaches for CanL and underscores the potential of CIC as a complementary tool in veterinary practice. As we move forward, larger studies will be essential to confirm these findings and establish definitive cut-offs for clinical application.

Diagnosis of canine intestinal parasites: Improved detection of Dipylidium caninum infection through coproantigen testing

Intestinal parasites, including cestodes like Dipylidium caninum, are common in dogs in the United States of America (USA), but fecal flotation consistently, and, at times, dramatically, fails to identify many of these infections. To determine the extent to which including coproantigen testing for D. caninum would improve the identification of dogs infected with this cestode, we evaluated fecal samples from 877 dogs (589 pet and 288 from municipal shelters) from six USA states using zinc sulfate (specific gravity 1.24) fecal flotation with centrifugation along with coproantigen detection for Giardia sp., hookworms, ascarids, and Trichuris vulpis. For D. caninum, PCR of perianal swabs was included. Intestinal parasite infections were identified, using centrifugal fecal flotation or coproantigen, in 265 dogs (13.2 % pet, 64.9 % shelter). Dipylidium caninum infection was detected in 5.6 % of dogs with the combination of coproantigen and centrifugal fecal flotation, and 7.3 % of dogs when perianal swab results were included; prevalence varied by diagnostic method, population, and geographic region. In pet dogs, D. caninum infection was identified by fecal flotation (0), coproantigen (2.2 %), or perianal swabs (1.2 %). The same methods revealed infection in 0.3 %, 12.5 %, and 11.1 % of shelter dogs, respectively. Frequent use of praziquantel in shelter dogs (116/288; 40.3 %) may have reduced prevalence. Positive and negative agreement of D. caninum coproantigen with perianal swab PCR in pet dogs was 85.7 % and 98.8 %, respectively. Multiple logistic regression analysis accounting for region, population, and age found D. caninum infection to be more common in shelter dogs relative to pet (adjusted OR 4.91 [2.48, 10.24]) and in the Southcentral and Southeast regions relative to North (adjusted OR 9.59 [1.92, 174.13] and 17.69 [3.67, 318.09] respectively). Coproantigen testing also enhanced the detection of other intestinal parasites over fecal flotation alone, including Giardia sp. (14.7 % vs 3.3 %), hookworms (13.8 % vs 8.4 %), ascarids (2.9 % vs 2.2 %), and T. vulpis (2.9 % vs 1.4 %). Together, these data indicate that the coproantigen assay employed increases detection of D. caninum infections several fold, supporting the use of this test in clinical practice, and add to a growing body of research documenting enhanced diagnosis through implementation of multiple laboratory-based methods.

Carnivore chaphamaparvovirus-1 (CaChPV-1) infection in diarrheic dogs reveals viral endotheliotropism in intestine and lung

BACKGROUND

Carnivore chaphamaparvovirus-1 (CaChPV-1) is a parvovirus identified in dogs and association of infection with diarrhea is controversial. Information on whether tissue tropism persists is lacking.

OBJECTIVES

To determine the disease association of CaChPV-1 in dogs with diarrhea and to investigate viral tropism and genetic diversity.

ANIMALS AND METHODS

CaChPV-1 infection was investigated in five recently deceased puppies and designed a retrospective study to determine whether the presence of CaChPV-1 is associated with diarrhea. The retrospective study was conducted in 137 intestinal tissue samples and 168 fecal samples obtained from 305 dogs. CaChPV-1 tissue localization was determined using in situ hybridization, and CaChPV-1 complete genomes obtained from dead puppies and retrospective study were sequenced and analyzed.

RESULTS

CaChPV-1 was detected in 6.56% (20/305) of tested dogs, including 14 diarrheic- and 6 non-diarrheic dogs, and was significant in puppies with diarrhea (p = 0.048). Among the CaChPV-1-positive diarrheic dogs, one sample was obtained from intestinal tissue and 13 samples were fecal samples. However, six CaChPV-1 positive non-diarrheic dogs were based on fecal samples but not on intestinal tissue. Within the age range, the presence of CaChPV-1 was significant in puppies (p < 0.00001) and was mainly localized in the stromal and endothelial cells of intestinal villi and pulmonary alveoli. Phylogenetic analysis indicated genetic diversity of CaChPV-1 Thai strains that were mostly clustered within the sequences found in China.

CONCLUSIONS

Although definitive pathogenesis of CaChPV-1 remains undetermined, this study provides evidence supporting that CaChPV-1 localizes in canine cells and could play a potential role as an enteric pathogen.

Lifetime prevalence of owner-reported medical conditions in the 25 most common dog breeds in the Dog Aging Project pack

Introduction

Large scale data on the prevalence of diverse medical conditions among dog breeds in the United States are sparse. This cross-sectional study sought to estimate the lifetime prevalence of medical conditions among US dogs and to determine whether purebred dogs have higher lifetime prevalence of specific medical conditions compared to mixed-breed dogs.

Methods

Using owner-reported survey data collected through the Dog Aging Project (DAP) Health and Life Experience Survey for 27,541 companion dogs, we identified the 10 most commonly reported medical conditions in each of the 25 most common dog breeds within the DAP cohort. Lifetime prevalence estimates of these medical conditions were compared between mixed-breed and purebred populations. The frequency of dogs for whom no medical conditions were reported was also assessed within each breed and the overall mixed-breed and purebred populations.

Results

A total of 53 medical conditions comprised the top 10 conditions for the 25 most popular breeds. The number of dogs for whom no medical conditions were reported was significantly different (p = 0.002) between purebred (22.3%) and mixed-breed dogs (20.7%). The medical conditions most frequently reported within the top 10 conditions across breeds were dental calculus (in 24 out of 25 breeds), dog bite (23/25), extracted teeth (21/25), osteoarthritis (15/25), and Giardia (15/25).

Discussion

Purebred dogs in the DAP did not show higher lifetime prevalence of medical conditions compared to mixed-breed dogs, and a higher proportion of purebred dogs than mixed-breed dogs had no owner-reported medical conditions. Individual breeds may still show higher lifetime prevalence for specific conditions.

Subjective vision assessment in companion dogs using dogVLQ demonstrates age-associated visual dysfunction

Introduction

Dim light vision as assessed by proxy and clinical tools is commonly impaired in older humans and impacts quality of life. Although proxy visual assessment tools have been developed for dogs, it is unclear if they are sensitive enough to detect subtle visual dysfunction in older dogs. We sought to determine if a newly designed proxy visual function questionnaire could detect age-associated differences in visual behaviors in varying lighting conditions in dogs.

Methods

A 27-item questionnaire (the dog variable lighting questionnaire, dogVLQ) was designed to assess visual behavior in dogs in different lighting settings. We conducted the dogVLQ, a previously validated visual function questionnaire the dog vision impairment score and performed light- and dark-adapted electroretinography (ERG) on a subset of dogs. Questionnaire scores were analyzed for dog age associations using correlation analysis.

Results

Questionnaire responses from 235 dog owners were obtained (122 female, 112 male dogs), 79 of which underwent ERG (43 female, 36 male dogs). Bright light visual behavior was significantly associated with light-adapted bright flash ERG amplitudes, visual behavior in near darkness was associated with dark-adapted ERG amplitudes. The dogVLQ identified worse vision in older dogs in bright light, dim light, and darkness; predicted onset was younger for vision in near darkness. Older dogs had more difficulty navigating transitions between lighting conditions.

Discussion

Subjective dog owner assessment of visual function associates with objective measurement of retinal function in dogs and supports reduced vision-mediated behaviors in older dogs.

COAST Development Group's international consensus guidelines for the treatment of canine osteoarthritis

This report describes consensus guidelines and recommendations for the treatment of canine osteoarthritis (OA) according to the "Canine OsteoArthritis Staging Tool excluding radiography" (COASTeR) stage of OA, by the COAST Development Group. The recommendations are based on evidence-based medicine and clinical experience and are proposed with international relevance in mind. The aim is to provide veterinarians with a practical reference to consolidated information and to support the development of patient-specific OA management protocols and informed treatment choices based on the stage of OA.

Characterization of the Gut Microbiome in Healthy Dogs and Dogs with Diabetes Mellitus

With a close pathogenetic resemblance to human diabetes, canine Diabetes Mellitus, a chronic metabolic disease featuring abnormally high blood sugar levels, is increasing in prevalence worldwide. Unlike humans, canine glycemic control requires life-long insulin injections and dietary control in most cases, thereby jeopardizing diabetic dogs' quality of life and increasing the difficulty of disease control. While many research studies have focused on elucidating the relationship between the canine gut microbiome and diseases, there is currently no research on the subject of diabetes mellitus in dogs. We hypothesized that the gut microbiome of canines with diabetes mellitus is different from that of healthy controls. Thus, we performed targeted 16S rRNA sequencing and comprehensive bioinformatic analysis to compare the gut microbiome profiles of 16 diabetic dogs with those of 32 healthy dogs. Clostridioides difficile, Phocaeicola plebeius, Lacrimispora indolis, and Butyricicoccus pullicaecorum were found to be enriched in diabetic dogs. A distinct shift towards carbohydrate degradation metabolic pathways was found to be differentially abundant in the diabetic subjects. Alteration of the co-occurrence network was also evident in the diabetic group. In conclusion, our study suggests that the gut microbial landscape differs in diabetic canines at the genera, species, functional, and network levels. These findings have significant implications for disease management, and thus warrant further research.

Age-associated changes in electroretinography measures in companion dogs

PURPOSE

To determine the association between age and retinal full-field electroretinographic (ERG) measures in companion (pet) dogs, an important translational model species for human neurologic aging.

METHODS

Healthy adult dogs with no significant ophthalmic abnormalities were included. Unilateral full-field light- and dark-adapted electroretinography was performed using a handheld device, with mydriasis and topical anaesthesia. Partial least squares effect screening analysis was performed to determine the effect of age, sex, body weight and use of anxiolytic medication on log-transformed ERG peak times and amplitudes; age and anxiolytic usage had significant effects on multiple ERG outcomes. Mixed model analysis was performed on data from dogs not receiving anxiolytic medications.

RESULTS

In dogs not receiving anxiolytics, median age was 118 months (interquartile range 72-140 months, n = 77, 44 purebred, 33 mixed breed dogs). Age was significantly associated with prolonged peak times of a-waves (dark-adapted 3 and 10 cds/m2 flash p < 0.0001) and b-waves (cone flicker p = 0.03, dark-adapted 0.01 cds/m2 flash p = 0.001). Age was also significantly associated with reduced amplitudes of a-waves (dark-adapted 3 cds/m2 flash p < 0.0001, 10 cds/m2 flash p = 0.005) and b-waves (light-adapted 3 cds/m2 flash p < 0.0001, dark-adapted 0.01 cds/m2 flash p = 0.0004, 3 cds/m2 flash p < 0.0001, 10 cds/m2 flash p = 0.007) and flicker (light-adapted 30 Hz 3 cds/m2 p = 0.0004). Within the Golden Retriever breed, these trends were matched in a cross-sectional analysis of 6 individuals that received no anxiolytic medication.

CONCLUSIONS

Aged companion dogs have slower and reduced amplitude responses in both rod- and cone-mediated ERG. Consideration of anxiolytic medication use should be made when conducting ERG studies in dogs.

Quantitative Analysis of Brain CT Perfusion in Healthy Beagle Dogs: A Pilot Study

Brain computed tomography (CT) perfusion is a technique that allows for the fast evaluation of cerebral hemodynamics. However, quantitative studies of brain CT perfusion in veterinary medicine are lacking. The purpose of this study was to investigate the normal range of perfusion determined via CT in brains of healthy dogs and to compare values between white matter and gray matter, differences in aging, and each hemisphere. Nine intact male beagle dogs were prospectively examined using dynamic CT scanning and post-processing for brain perfusion. Regional cerebral blood volume (rCBV), regional cerebral blood flow (rCBF), mean transit time, and time to peak were calculated. Tissue ROIs were drawn in the gray matter and white matter of the frontal, temporal, parietal, and occipital lobes; caudate nucleus; thalamus; piriform lobe; hippocampus; and cerebellum. Significant differences were observed between the white matter regions and gray matter regions for rCBV and rCBF (p < 0.05). However, no significant differences were identified between hemispheres and between young and old groups in brain regions. The findings obtained in this study involving healthy beagle dogs might serve as a reference for regional CT perfusion values in specific brain regions. These results may aid in the characterization of various brain diseases in dogs.

Effect of Aging on the Immune Response to Core Vaccines in Senior and Geriatric Dogs

Elderly dogs are steadily increasing worldwide as well as veterinarians' and owners' interest in their health and wellness. Aging is not a disease, but a combination of changes negatively affecting the organism in general and the immune system in particular, resulting in a decline in protection over time. The aim of this study was to measure the specific serum antibody titers against the main dangerous and widespread viral diseases preventable by core vaccinations in senior and geriatric dogs using the in-practice test VacciCheck. A cohort of three hundred fifty elderly dogs was analyzed for Protective Antibody Titers (PATs) against CPV-2, CDV and CAdV-1. The age ranged from 5 to 19 years, with two hundred fifty-eight seniors (73.7%) and ninety-two geriatrics (26.3%), and 97.4% of them were vaccinated at least once in their lives. More than half of the entire study population (52.9%) had PATs simultaneously for all three diseases, with 80.5% seniors and 19.5% geriatrics. Specific PATs were found in 88.6% of aging dogs for CPV-2, 82.3% for CadV-1 and 66.0% for CDV, demonstrating that unprotected aging dogs represent a minority. Unexpectedly, the larger elderly dogs resulted as more protected than smaller ones for CPV-2. Protection then decreases over time, with geriatric dogs less protected than senior ones. Veterinary practitioners should therefore always consider whether to maintain core vaccinations in aging dogs as in adults on a three-year basis or opt instead for closer boosters (every 1 or 2 years). PATs for core vaccines could then represent a good biomarker of protection and their titration could become a standard of care, especially in such a sensitive period of the dogs' life.

Winning the race with aging: age-related changes in gait speed and its association with cognitive performance in dogs

Introduction

In humans, gait speed is a crucial component in geriatric evaluation since decreasing speed can be a harbinger of cognitive decline and dementia. Aging companion dogs can suffer from age-related mobility impairment, cognitive decline and dementia known as canine cognitive dysfunction syndrome. We hypothesized that there would be an association between gait speed and cognition in aging dogs.

Methods

We measured gait speed on and off leash in 46 adult and 49 senior dogs. Cognitive performance in senior dogs was assessed by means of the Canine Dementia Scale and a battery of cognitive tests.

Results

We demonstrated that dogs' food-motivated gait speed off leash is correlated with fractional lifespan and cognitive performance in dogs, particularly in the domains of attention and working memory.

Discussion

Food-motivated gait speed off leash represents a relatively easy variable to measure in clinical settings. Moreover, it proves to be a more effective indicator of age-related deterioration and cognitive decline than gait speed on leash.

Social determinants of health and disease in companion dogs: a cohort study from the Dog Aging Project

Exposure to social environmental adversity is associated with health and survival across many social species, including humans. However, little is known about how these health and mortality effects vary across the lifespan and may be differentially impacted by various components of the environment. Here, we leveraged a relatively new and powerful model for human aging, the companion dog, to investigate which components of the social environment are associated with dog health and how these associations vary across the lifespan. We drew on comprehensive survey data collected on 21,410 dogs from the Dog Aging Project and identified five factors that together explained 33.7% of the variation in a dog's social environment. Factors capturing financial and household adversity were associated with poorer health and lower physical mobility in companion dogs, while factors that captured social support, such as living with other dogs, were associated with better health when controlling for dog age and weight. Notably, the effects of each environmental component were not equal: the effect of social support was 5× stronger than financial factors. The strength of these associations depended on the age of the dog, including a stronger relationship between the owner's age and the dog's health in younger as compared to older dogs. Taken together, these findings suggest the importance of income, stability and owner's age on owner-reported health outcomes in companion dogs and point to potential behavioral and/or environmental modifiers that can be used to promote healthy aging across species.

Evaluating Disease Patterns of Military Working Dogs in the Republic of Korea: A Retrospective Study

The purpose of this study was to evaluate disease patterns among military working dogs (MWDs) at the Armed Forces Medical Research Institute (AFMRI) to provide basic medical data on Korean MWDs. The medical records of procedures performed at AFMRI between November 2017 and March 2021 were reviewed. Physical examination, diagnostic imaging, and laboratory tests were performed according to the status of each dog. A total of 353 MWDs (215 males and 138 females; mean age, 6 ± 3 years) were analyzed in this study. Among Korean MWDs, gastrointestinal (GI) disorders are the most frequently diagnosed, followed by dental and musculoskeletal disorders. Foreign body (FB) ingestion had the highest prevalence of GI disorders, with the most common FB being a leather collar or leash. General and dental surgeries, including removal of gastric FB and tooth extraction, were routinely performed at the AFMRI. Preventative care focusing on dental disease and FB ingestion may be helpful for effective performance and good quality of life in MWDs, with the regular assessment and prevention of environmental factors that may contribute to behavioral problems such as FB ingestion, coprophagy, and anorexia.

Molecular evidence of widespread benzimidazole drug resistance in Ancylostoma caninum from domestic dogs throughout the USA and discovery of a novel β-tubulin benzimidazole resistance mutation

Ancylostoma caninum is an important zoonotic gastrointestinal nematode of dogs worldwide and a close relative of human hookworms. We recently reported that racing greyhound dogs in the USA are infected with A. caninum that are commonly resistant to multiple anthelmintics. Benzimidazole resistance in A. caninum in greyhounds was associated with a high frequency of the canonical F167Y(TTC>TAC) isotype-1 β-tubulin mutation. In this work, we show that benzimidazole resistance is remarkably widespread in A. caninum from domestic dogs across the USA. First, we identified and showed the functional significance of a novel benzimidazole isotype-1 β-tubulin resistance mutation, Q134H(CAA>CAT). Several benzimidazole resistant A. caninum isolates from greyhounds with a low frequency of the F167Y(TTC>TAC) mutation had a high frequency of a Q134H(CAA>CAT) mutation not previously reported from any eukaryotic pathogen in the field. Structural modeling predicted that the Q134 residue is directly involved in benzimidazole drug binding and that the 134H substitution would significantly reduce binding affinity. Introduction of the Q134H substitution into the C. elegans β-tubulin gene ben-1, by CRISPR-Cas9 editing, conferred similar levels of resistance as a ben-1 null allele. Deep amplicon sequencing on A. caninum eggs from 685 hookworm positive pet dog fecal samples revealed that both mutations were widespread across the USA, with prevalences of 49.7% (overall mean frequency 54.0%) and 31.1% (overall mean frequency 16.4%) for F167Y(TTC>TAC) and Q134H(CAA>CAT), respectively. Canonical codon 198 and 200 benzimidazole resistance mutations were absent. The F167Y(TTC>TAC) mutation had a significantly higher prevalence and frequency in Western USA than in other regions, which we hypothesize is due to differences in refugia. This work has important implications for companion animal parasite control and the potential emergence of drug resistance in human hookworms.

Use of urinalysis during baseline diagnostics in dogs and cats: an open survey

OBJECTIVES

To describe how veterinarians utilise and perform urinalyses for dogs and cats.

MATERIALS AND METHODS

A survey, developed and distributed through the Veterinary Information Network, enlisted veterinarians who perform urinalyses for dogs and cats. Participants were directed to question banks based on whether urinalyses were performed in-house, by an outside diagnostic laboratory, or using an in-house automated instrument. Participants using multiple methods were directed to questions that related to the chosen methods.

RESULTS

A total of 1059 predominantly first-opinion clinicians from the USA and Canada completed the survey. Participants performed urinalyses much less frequently than blood work during a routine examination. The most common factors preventing participants from performing a urinalysis with blood work included clients' financial constraints, difficulty obtaining urine and lack of perceived diagnostic need. The most common reasons for submission to a diagnostic laboratory included efficiency, more trusted results and convenience. Speed of obtaining results was the most common reason for performing urinalyses in-house. Of the participants who performed in-house urinalyses, fewer always performed a manual sediment examination (79%) as compared with urine-specific gravity (99%) and manual dipstick (87%).

CLINICAL SIGNIFICANCE

This survey documents that urinalysis is often not used in senior patients as recommended by recent clinical guidelines for dogs and cats which can result in decreased diagnosis and impaired management of subclinical disease. There is significant variability in urinalysis methods despite veterinary guidelines promoting standardisation, and this could lead to inaccurate results.

Geographic Distribution and Seasonality of Brown Dog Tick Lineages in the United States

Two lineages of brown dog ticks (Rhipicephalus sanguineus sensu lato (s.l.), Latreille [Acari: Ixodidae]) have been described in North America: temperate and tropical. To characterize the distribution of these lineages across this region and evaluate seasonal activity, a 12S rRNA mitochondrial gene fragment was sequenced from R. sanguineus s.l. collected from hundreds of dogs and cats from different locations across 25 of the 50 states from 2018 to 2021. Infestations with temperate lineage predominated (78.5%) and were identified on pets from 20 states, with most (83.5%) from areas with annual mean daily average temperature <20°C. Tropical lineage submissions were less common (19.3%), submitted from 15 states, and most (80.0%) tropical lineage ticks were from areas with an annual mean daily average temperature >20°C. Although travel history was not obtained for all dogs, when tropical lineage infestations were found in colder regions, follow up conversations with veterinarians suggested some of these infestations may have resulted from recent travel of dogs. A limited number (2.2%) of dogs from Arizona and Texas were co-infested with both lineages. Both temperate and tropical lineage ticks were collected from pets in every month of the year. Temperate lineage infestations were primarily collected March through August while tropical lineage infestations were more often collected June through November. These data confirm at least two lineages of R. sanguineus s.l. are present in the United States, each predominating in distinct, overlapping geographies, and suggest that peak activity of each lineage occurs at different times of the year.

Clinical, diagnostic and epidemiological implications of Hepatozoon spp., Babesia spp. and Leishmania infantum infection in cats and dogs in a Mediterranean periurban setting

Hepatozoon spp., Babesia spp. and Leishmania infantum are common parasites of dogs in Mediterranean countries and are less frequent in cats, particularly Babesia spp. and L. infantum. Moreover, there is limited information on coinfections between these parasites and on L. infantum's distribution in blood, skin and lymphoid tissue in cats. We used PCR and DNA sequencing to investigate the prevalence of these parasites and the aetiology of Hepatozoon spp. and Babesia spp., in blood, skin, spleen and lymph node samples from up to 212 stray cats and 82 abandoned dogs in southeast Spain. All except 2 dogs were healthy; instead, 112 cats had clinical signs. The estimated PCR prevalences (95% confidence interval) were 25% (19-31%) Hepatozoon felis in cats, 13% (6-21%) Hepatozoon canis in dogs, 1% (0-4%) Babesia vogeli in dogs, 0% Babesia spp. in cats and 21% (15-26%) and 44% (33-55%) L. infantum in cats and dogs, respectively, and infections were not associated with each other. Leishmania infantum prevalence in lymphoid tissue was significantly higher in dogs than in cats (p < 0.001), and dogs had higher parasite loads than cats (p = 0.012). Moreover, L. infantum prevalence was significantly higher in the skin and lymphoid tissue compared to blood in infected, asymptomatic animals but it was similar in cats with clinical signs, which also had higher parasite loads compared to infected, asymptomatic cats (p < 0.05). The study highlights significant differences between sympatric dogs and cats with respect to the parasite infections investigated, as well as the need to examine both lymphoid tissue and skin samples to maximise the sensitivity of L. infantum infection diagnosis.

2023 AAHA Senior Care Guidelines for Dogs and Cats

Veterinary professionals are taught to recognize that "old age is not a disease." However, clients may have the perception that older dogs and cats undergo an unavoidable physical, mental, and behavioral decline attributable simply to old age. The veterinary team's role includes providing medical care and support to senior pets to maintain their quality of life, as well as supporting and educating clients on proper senior animal care and addressing any misconceptions about the aging process. These Guidelines describe a systematic approach to the healthcare of the senior pet that is based on an evidence-guided assessment of both healthy and unhealthy canine and feline patients. By using evidence-guided medicine, which may include conventional and integrative approaches as well as environmental management for the senior pet, the patient's quality of life can be enhanced and potentially extended during this vulnerable life stage. Developing a senior program for the veterinary practice requires appropriate training of the entire healthcare team and includes a robust client education program that focuses on the wellbeing of the senior pet. Palliative and hospice care should be included in the education and information provided for both the veterinary team and the families of senior pets.

Epidemiology, genetic diversity, and association of canine circovirus infection in dogs with respiratory disease

Although canine circovirus (CanineCV)-associated with gastroenteritis has been well documented, the virus is also detectable in the respiratory discharge of dogs with respiratory disease. In this study, an epidemiological approach was used to explore the association between the presence of CanineCV and respiratory symptoms in dogs. Respiratory swabs were collected from 76 healthy dogs and 114 dogs with respiratory illness and tested for CanineCV using conventional PCR (cPCR). Furthermore, lung tissues collected from 15 necropsied dogs showing pneumonia were tested using the real-time PCR (qPCR) and in situ hybridization (ISH) technique. A total of 8.95% (17/190) of dogs were CanineCV positive, with a significant association (p = 0.013) in dogs with respiratory signs. Four necropsied dogs were qPCR positive with the CanineCV-DNA labeling localized in tracheobronchial lymphoid cells (3/4), pulmonary parenchyma, capillary endothelia, and mononuclear cells harboring in alveoli (2/4). Full-length genome sequences of seven CanineCV strains were analyzed, indicating that the detected CanineCV genome clustered in the CanineCV-4 genotype. Genetic recombination was also evident in the replicase (Rep) gene. Although the role of CanineCV primarily affecting lung lesions could not be determined from this study, the presence of CanineCV DNA in pulmonary-associated cells indicated the potential association of the virus with canine respiratory disease; thus, linking causality must be examined in further studies.

Prognostic factors associated with survival and hospitalization time in pediatric canine patients diagnosed with presumptive acute viral gastroenteritis

Background and Aim:

Acute viral gastroenteritis is one of the main causes of hospitalization in dogs during the 1^st year of life. This retrospective study aimed to describe a pediatric canine population presumptively diagnosed with acute viral gastroenteritis and to identify potential prognostic factors that influence hospitalization time (HT) and mortality.

Materials and Methods:

Canine patients up to 12 months of age diagnosed with presumptive acute viral gastroenteritis were searched retrospectively from two veterinary hospitals during a 5-year period (2015–2020). Information regarding patient signalment, prophylactic care, clinical signs, blood test results, presence of systemic inflammatory response syndrome, and additional treatments were recorded to analyze their association with HT and mortality. Only dogs with a complete medical record until death or discharge were included in the study.

Results:

Ninety-four dogs were identified: 76 dogs (80.9%) survived with a median HT of 5 days (range: 2–16 days) and 18 dogs (19.1%) died with a median HT of 3½ days (range: 1–8 days) after admission. The presence of fever and fresh frozen plasma (FFP) administration was significantly associated with a lower survival rate (p = 0.021 and p = 0.037) in the multivariate analysis. Among survivors, incomplete primo-vaccination, the presence of hematochezia, and FFP administration were considered independent predictors of time to clinical recovery (p = 0.026, p = 0.047, and p = 0.026, respectively), being associated with higher HT.

Conclusion:

The presence of fever and FFP administration was significantly associated with a lower survival rate. An inadequate primo-vaccination status prior to admission, hematochezia, and FFP administration was associated with longer HT in surviving patients. Further studies are needed to confirm the present results.

Evaluation of cognitive function in the Dog Aging Project: associations with baseline canine characteristics

Canine cognitive dysfunction (CCD) is a neurodegenerative disease in aging dogs. It has been described previously in relatively small cohorts of dogs using multiple different rating scales. This study aimed to use a minimally modified CCD rating scale developed by previous researchers to describe the prevalence of CCD more thoroughly in a large, nationwide cohort of companion dogs participating in the Dog Aging Project (DAP) (n = 15,019). Associations between various canine characteristics, predicted lifespan quartiles, and CCD were examined using univariable and multivariable logistic regression models and receiver operating curve (ROC) analysis. When controlling for all other characteristics, the odds of CCD increased 52% with each additional year of age. Among dogs of the same age, health status, breed type, and sterilization status, odds of CCD were 6.47 times higher in dogs who were not active compared to those who were very active. When controlling for age, breed type, activity level, and other comorbidities, dogs with a history of neurological, eye, or ear disorders had higher odds of CCD. Lifespan quartile analysis showed excellent discriminating ability between CCD positive and negative dogs. Weight-based lifespan quartile estimation could therefore serve as a tool to inform CCD screening by veterinarians.

Static posturography as a novel measure of the effects of aging on postural control in dogs

Aging is associated with impairment in postural control in humans. While dogs are a powerful model for the study of aging, the associations between age and postural control in this species have not yet been elucidated. The aims of this work were to establish a reliable protocol to measure center of pressure excursions in standing dogs and to determine age-related changes in postural sway. Data were obtained from 40 healthy adult dogs (Group A) and 28 senior dogs (Group B) during seven trials (within one session of data collection) of quiet standing on a pressure sensitive walkway system. Velocity, acceleration, root mean square, 95% ellipse area, range and frequency revolve were recorded as measures of postural sway. In Group A, reliability was assessed with intraclass correlation, and the effect of morphometric variables was evaluated using linear regression. By means of stepwise linear regression we determined that root mean square overall and acceleration in the craniocaudal direction were the best variables able to discriminate between Group A and Group B. The relationship between these two center-of-pressure (COP) measures and the dogs’ fractional lifespan was examined in both groups and the role of pain and proprioceptive deficits was evaluated in Group B. All measures except for frequency revolve showed good to excellent reliability. Weight, height and length were correlated with most of the measures. Fractional lifespan impacted postural control in Group B but not Group A. Joint pain and its interaction with proprioceptive deficits influence postural sway especially in the acceleration in the craniocaudal direction, while fractional lifespan was most important in the overall COP displacement. In conclusion, our study found that pressure sensitive walkway systems are a reliable tool to evaluate postural sway in dogs; and that postural sway is affected by morphometric parameters and increases with age and joint pain.

Stereotactic radiotherapy (10 Gy X 3) for canine nonlymphomatous intranasal tumors is associated with prolonged survival and minimal risk of severe radiotoxicity

OBJECTIVE

To describe oncologic outcomes following administration of a uniform stereotactic radiotherapy protocol (SRT; 10 Gy X 3) for canine intranasal tumors and to identify whether any clinical or dosimetric factors were predictive of event-free or overall survival time (EFST or OST).

ANIMALS

129 dogs.

PROCEDURES

In this single-institution retrospective study, the medical records database was searched for canine nonlymphomatous intranasal tumors treated with 10 Gy X 3 SRT between August 2013 and November 2020. Findings regarding adverse effects and outcomes were analyzed overall, for dogs grouped on the basis of life stage (mature adult, senior, or end of life), and for treatment-related or tumor-related variables to identify potential predictors of outcome.

RESULTS

After SRT, most dogs clinically improved with minimal acute radiotoxicity. The median EFST was 237 days; median OST was 542 days. Receipt of other tumor-directed therapies before or after SRT was associated with improved EFST in senior dogs (hazard ratio [HR], 0.416) and improved OST in mature adult (HR, 0.241) and senior dogs (HR, 0.348). In senior dogs, administration of higher near-minimum radiation doses was associated with improved EFST (HR, 0.686) and OST (HR, 0.743). In senior dogs, chondrosarcoma was associated with shorter OST (HR, 7.232), and in dogs at end of life, having a squamous cell or transitional carcinoma was associated with worse EFST (HR, 6.462).

CLINICAL RELEVANCE

This SRT protocol results in improved quality of life and prolonged OST for dogs of all life stages. Radiation protocol optimization or use of multimodal therapy may further improve outcomes.

Use of health parameter trends to communicate pet health information in companion animal practice: A mixed methods analysis

BACKGROUND

Reviewing patient health parameter trends can strengthen veterinarian-client-patient relationships. The objective of this study is to identify characteristics associated with veterinarians' communication of health parameter trends to companion animal clients.

METHODS

Using a sequential exploratory mixed methods design, independent pet owner (n = 27) and veterinarian (n = 24) focus groups were conducted and analysed via content analysis to assess perceptions of how health parameter trends are communicated by veterinarians. Subsequently, a quantitative assessment of video recorded veterinary appointments (n = 917) compared characteristics identified in focus groups with health parameter trend discussions in practice. A mixed logistic model was used to assess characteristics associated with the occurrence of weight trend discussions.

RESULTS

Fifteen characteristics relating to veterinarians' use of health parameter trends were identified across focus groups. Veterinarians discussed 77 health parameter trends in relation to bodyweight (57/77), blood work (15/77) and other health parameters (5/77), within 73 (73/917) appointments. The odds of a weight trend discussion were higher if the veterinarian identified the pet as overweight or obese compared to an ideal bodyweight (odds ratio (OR) = 2.17; 95% confidence interval (CI) = 1.15-4.09; p = 0.016).

CONCLUSION

Mention of a health parameter trend was uncommon and rarely included use of visual aids. Health parameter trends related to bodyweight were discussed reactively, rather than proactively.

Delineation of altered brain proteins associated with furious rabies virus infection in dogs by quantitative proteomics

Rabies is a fatal zoonotic disease caused by rabies virus (RABV). Despite the existence of control measures, dog-transmitted human rabies accounts for ˃95% reported cases due to unavailability of sensitive diagnostic methods, inadequate understanding of disease progression and absence of therapeutics. In addition, host factors and their role in RABV infection are poorly understood. In this study, we used 8-plex iTRAQ coupled with HRMS approach to identify differentially abundant proteins (DAPs) of dog brain associated with furious rabies virus infection. Total 40 DAPs including 26 down-regulated and 14 up-regulated proteins were statistically significant in infected samples. GO annotation and IPA showed that calcium signaling and calcium transport, efficient neuronal function, metabolic pathway associated proteins were mostly altered during this infection. Total 34 proteins including 10 down-regulated proteins pertaining to calcium signaling and calcium transport pathways were successfully verified by qRT-PCR and two proteins were verified by western blot, thereby suggesting these pathways may play an important role in this infection. This study provides the map of altered brain proteins and some insights into the molecular pathophysiology associated with furious rabies virus infection. However, further investigations are required to understand their role in disease mechanism. SIGNIFICANCE: Transmission of rabies by dogs poses the greatest hazard world-wide and the rare survival of post-symptomatic patients as well as severe neurological and immunological problems pose a question to understand the molecular mechanism involved in rabies pathogenesis. However, information regarding host factors and their function in RABV infection is still inadequate. Our study has used an advanced quantitative proteomics approach i.e. 8-plex iTRAQ coupled with HRMS and identified 40 DAPs in furious rabies infected dog brain tissues compared to the controls. Further analysis showed that calcium signaling and transport pathway, efficient neuronal functions and metabolic pathway associated brain proteins were most altered during furious rabies virus infection. This data provides a map of altered brain proteins which may have role in furious rabies virus infection. Hence, this will improve our understanding of the molecular pathogenesis of RABV infection.

Risk factors and impact of COVID-19-related clinic closures on the detection of gastrointestinal parasites in dogs, a cross-sectional study

Infections with endoparasites, especially gastrointestinal helminths, are a common finding in client-owned dogs. The Community Practice section at the Ohio State University Veterinary Medical Center (OSU-VMC) follows Companion Animal Parasite Council, American Animal Hospital Association, and American Veterinary Medical Association guidelines for parasitology by recommending annual fecal analyses for dogs and prescribing year-round, broad-spectrum parasite preventatives. There is increasing interest in determining if parasite occurrence is changing in client-owned dogs. Therefore, a retrospective study was designed to examine risk factors associated with the detection of parasites in samples submitted to the OSU-VMC Clinical Veterinary Parasitology Diagnostic Laboratory. Of the 1198 canine fecal samples, 254 (21.2%) of these samples had a positive fecal analysis for gastrointestinal (GI) parasites. The age of the dog, time of year, reproductive status, purpose of fecal examination, GI signs, and type of parasite preventatives were assessed as potential risk factors for GI parasite infection in dogs. To determine if Coronavirus Disease 2019 (COVID-19)-associated hospital restrictions impacted the number of fecal examinations performed, data from January to December 2020, was compared to the same period in 2019. There was nearly a 50% reduction in canine fecal samples submitted to the OSU-VMC Clinical Veterinary Parasitology Diagnostic Laboratory in March 2020 compared to March 2019. At least one canine GI parasite was found in over 20% of all 1198 canine fecal samples (21.2%, 254/1198). The most commonly detected canine GI parasite in all the fecal samples was hookworm at 9.6% (115/1198), followed by Giardia sp. at 7.6% (91/1198). Age, use of parasite preventatives, breed, and reproductive status were found to be associated with parasite occurrence in the dog samples. Identifying such risk factors in dogs will guide veterinarians to advise annual fecal examinations more strongly to clients with high-risk dogs or when routine health visits are postponed for an extended period.

Shear wave velocity measurements obtained in different regions are repeatable for presumed normal canine lymph nodes: A pilot study

Shear wave elastography (SWE) has been applied as a noninvasive method for predicting regional lymph node (LN) metastases in human and veterinary patients. However, published studies describing standardized protocols and repeatability of this technique are currently lacking. The objective of this prospective, pilot, observer agreement study was to determine whether different shear wave velocity (SWV) measurements obtained in different regions of presumed normal canine LNs would be repeatable. Two imagers consecutively performed shear wave elastography of submandibular, superficial inguinal, and popliteal LNs in 10, clinically healthy adult dogs. Ten elastograms of each LN were acquired by each imager. In each adequate elastogram, three regions of interest (ROIs) were placed in the softest and stiffest region of the LN. Additionally, one ROI was drawn covering the entire LN. In each ROI, mean, median, and maximum SWVs were calculated. Mean values for the mean, median, and maximum SWVs varied from 2.33 to 3.10 m/s, 2.32 to 3.10 m/s, and 2.61 to 4.09 m/s, respectively. Intra- and interobserver agreements were acceptable. Superficial inguinal LNs demonstrated the highest intra- and interobserver agreement, followed by the popliteal and the submandibular LNs, respectively. Using the different measurements (mean, median, or maximum SWVs) had no significant effect on the intra- and interobserver variability, neither did the region (softest, stiffest, or entire LN). Findings indicated that all evaluated measurements and regions could be used to obtain reliable elastography data of presumed normal canine LNs. Clinical trials in dogs with cancer are necessary to compare SWVs of metastatic LNs with the reported SWVs and evaluate whether various measurements and regions can also be used in metastatic LNs.

Molecular and Pathological Investigations of Selected Viral Neuropathogens in Rabies-Negative Brains of Cats and Dogs Revealed Neurotropism of Carnivore Protoparvovirus-1

Throughout the year, the Thai Red Cross Society (TRCS), Bangkok, Thailand, received more than 100 animals that died of suspected rabies due to neurological clinical signs. Concerning the role of viral infection in the brain in the outcome of neurological diseases in cats and dogs, a comprehensive study was conducted of 107 brain samples of cats and dogs submitted to the TRCS from August 2019 to August 2020. Selective molecular screening using conventional polymerase chain reaction (PCR) and reverse transcription PCR targeting nine viral pathogens was employed in addition to histopathological investigations. The results showed that carnivore protoparvovirus-1 (CPPV-1) was detected in 18.69% of the cats and dogs sampled (20/107). These results were found in young and old animals; the brain tissue did not show any pathological changes suggesting encephalitis or cerebellar hypoplasia. In addition, feline calicivirus, feline alphaherpesvirus-1, feline coronavirus, and canine distemper virus were also detected, providing a broader range of potential viral infections to consider in the clinical manifestation of neurological disorders in companion animals. The detection of all pathogens was confirmed by the localization of each viral antigen in various resident brain cells using immunohistochemistry. A unique L582S amino acid substitution of the non-structural protein 1 gene coding sequence, speculated to be associated with the neurotropism of CPPV-1 in cats and dogs, was not evident. In conclusion, this study revealed a noteworthy neurotropism of CPPV-1 in both cats and dogs without neurological lesions.

Successful and Unsuccessful Brain Aging in Pets: Pathophysiological Mechanisms behind Clinical Signs and Potential Benefits from Palmitoylethanolamide Nutritional Intervention

Simple Summary

Cognitive dysfunction syndrome is a common yet underreported neurodegenerative disorder of elderly dogs and cats and a natural model of human Alzheimer’s disease. The increasingly expanding life expectancy means a larger proportion of affected animals in the coming decades. Although far from being curative, available treatments are more effective the sooner they are started. Educating veterinary practitioners and owners in the early recognition of age-related cognitive dysfunction is thus mandatory. By shedding light on the mechanism underlying the disease, novel and more effective approaches might be developed. Emerging evidence shows that successful and unsuccessful brain aging share a common underlying mechanism that is neuroinflammation. This process involves astrocytes, microglia, and mast cells and has a restorative homeostatic intent. However, for reasons not fully elucidated yet, neuroinflammation can also exert detrimental consequences substantially contributing to neurodegeneration. Here we summarize the evidence accumulated so far on the pathogenic role of neuroinflammation in the onset and progression of age-related neurodegenerative disorders, such as Alzheimer’s disease. The potential benefit of palmitoylethanolamide dietary intervention in rebalancing neuroinflammation and exerting neuroprotection is also discussed.

Abstract

Canine and feline cognitive dysfunction syndrome is a common neurodegenerative disorder of old age and a natural model of human Alzheimer’s disease. With the unavoidable expanding life expectancy, an increasing number of small animals will be affected. Although there is no cure, early detection and intervention are vitally important to delay cognitive decline. Knowledge of cellular and molecular mechanisms underlying disease onset and progression is an equally decisive factor for developing effective approaches. Uncontrolled neuroinflammation, orchestrated in the central nervous system mainly by astrocytes, microglia, and resident mast cells, is currently acknowledged as a hallmark of neurodegeneration. This has prompted scientists to find a way to rebalance the altered crosstalk between these cells. In this context, great emphasis has been given to the role played by the expanded endocannabinoid system, i.e., endocannabinoidome, because of its prominent role in physiological and pathological neuroinflammation. Within the endocannabinoidome, great attention has been paid to palmitoylethanolamide due to its safe and pro-homeostatic effects. The availability of new ultramicronized formulations highly improved the oral bioavailability of palmitoylethanolamide, paving the way to its dietary use. Ultramicronized palmitoylethanolamide has been repeatedly tested in animal models of age-related neurodegeneration with promising results. Data accumulated so far suggest that supplementation with ultramicronized palmitoylethanolamide helps to accomplish successful brain aging.

Canine bocavirus-2 infection and its possible association with encephalopathy in domestic dogs

Canine bocaviruses (CBoVs) have been recognized as pathogens associated with intestinal diseases. Hematogenous spreading caused by CBoV has been documented and may potentiate the virus entry across the blood-brain barrier to initiate a brain infection. This study focused attention on CBoV detection in cases of encepahlopathy and attempted to determine its viral localization. A total of 107 dog brains that histologically exhibited encephalopathy (ED) were investigated for the presence of CBoVs using polymerase chain reaction (PCR). Thirty-three histologically normal brain samples from dogs were used as a control group (CD). CBoV-2 was detected in 15 ED dogs (14.02%) but not in CD dogs (p = 0.02), while no CBoV-1 and -3 were detected. Among the CBoV-2 positive dogs, brain histological changes were characterized by nonsuppurative encephalitis, with inclusion body-like materials in some brains. In situ hybridization (ISH) and transmission electron microscopy (TEM) confirmed the presence of CBoV-2 viral particles in glial cells, supporting neurotropism of this virus. ISH signals were also detected in the intestines, lymphoid organs, and the heart, suggesting both enteral and parenteral infections of this virus. Whole genome characterization and evolutionary analysis revealed genetic diversity of CBoV-2 sequences and it was varying among the different countries where the virus was detected. This study points to a possible association of CBoV-2 with encephalopathy in dogs. It also highlights the genetic diversity and cellular tropism of this virus.

Rational use of diagnostic and screening tests

Veterinarians have a vast and ever-expanding array of diagnostic tests available to them. However, this abundance can be an embarrassment of riches that confounds diagnosis and undermines patient care if we do not make critical and informed decisions about the selection and interpretation of the tests we employ. Effective use of diagnostic tests requires a deliberate and informed approach. We must consider the strengths and weaknesses of the tests themselves and the clinical context, and we must be wary of the many biases that skew our use and interpretation of diagnostic tests. Understanding sensitivity and specificity, likelihood, prevalence and predictive value, the basic principles of Bayesian reasoning, and the cognitive biases that drive inappropriate testing are all critical to ensuring our use of imaging and laboratory testing improves patient outcomes.

Reasons for Exclusion of Apparently Healthy Mature Adult and Senior Dogs From a Clinical Trial

Background: Interventional clinical trials intended to maintain health in aging dogs are unusual and require particular attention to exclusion criteria.

Objectives: To describe reasons for exclusion when a mature adult and senior canine population with normal health status was sought.

Animals: Fifty six companion dogs nominated for a randomized controlled trial (RCT).

Procedures: Exclusions occurred within Stage 1 (S1): owner-provided survey information; Stage 2 (S2): medical records review; and Stage 3 (S3): screening examination and within Owner, Dog, or Other factor categories.

Results: Of 56 nominated dogs, 39 were excluded at S1 (n = 19), S2 (n = 5), and S3 (n = 15), respectively. Dogs were excluded for Owner (n = 4), Dog (n = 27), Other (n = 6), and concurrent (Owner + Dog; n = 2) factors. The most common exclusion period was S1 (n = 19), with weight outside the target range being the most common exclusion factor in that stage (n = 10). Heart murmurs were the second most common exclusion factor (S1: n = 1; S3: n = 5); suspected or confirmed systemic illness was third most common (S1: n = 2; S2: n = 3; S3: n = 2). Among dogs who passed S1 and S2 screening (n = 32), 15 dogs (48%) were excluded at S3, for heart murmur > grade II/VI (n = 5), cardiac arrhythmias (n = 2), and clinicopathologic abnormalities (n = 2).

Conclusions and Clinical Relevance: Dogs nominated for a clinical trial for healthy mature adult and senior dogs were excluded for size, previous diagnoses, and newly discovered cardiac abnormalities. For future interventions in mature adult and senior dogs of normal health status, it is important to define expected age-related abnormalities to ensure that meaningful exclusion criteria are used.

How Old Is My Dog? Identification of Rational Age Groupings in Pet Dogs Based Upon Normative Age-Linked Processes

Behavioral development is a lifelong process where cognitive traits such as learning and memory may be expected to take quadratic or linear trajectories. It is common practice for operational purposes to reduce study subjects into chronological categories when conducting research. However, there are no agreed-upon thresholds for this practice, and the lack of standardization may hinder comparison between studies of normative and pathological aging. In this perspective review, chronological categories have been identified that can be considered to represent normative cognitive and neurological aging in domestic family dogs. These categories work to capture age-related developmental trajectories for the majority of dog breeds. It is encouraged that researchers studying cognition and behavior, pathological cognitive deficits, or welfare of dogs across age categories utilize the categories presented here to best enable comparison between studies. The proposed groups could also support education programs informing owners of what behavioral changes to expect in their dog as they age, but they cannot be used to reflect health-based needs associated with breed-specific morbidity. The use of the age categories proposed here highlights significant welfare issues for breeds with the shortest average lifespans (e.g., the Great Dane). Studies show no evidence of an increased rate of behavioral or cognitive aging in short-lived breeds, and the shortest-lived breeds are most likely to die when classified by the proposed categories as Mature Adults. Adoption of these chronological categories in future research would aid comparison between studies and identification of non-normative age-related pathologies.

Senior Pet Nutrition and Management

Senior dogs and cats commonly present to veterinary clinics for wellness examinations and for illness. Nutritional needs change in healthy elder pets compared with the young adult life stage. Veterinary health care teams must provide nutritional assessments and individual recommendations, recognizing there is no defined nutrient profile for seniors. Individual variation prevents a one-size-fits-all approach. Advancing age places pets at risk for developing medical conditions. Early detection can lead to earlier nutritional intervention to support recovery, health, and quality of life. However, comorbidities may present a nutritional conundrum, requiring prioritization of problems and nutritional triage to balance needs.

Canine infection with Dirofilaria immitis, Borrelia burgdorferi, Anaplasma spp., and Ehrlichia spp. in the United States, 2013-2019

BACKGROUND

Dogs in the US are commonly infected with vector-borne pathogens, including heartworm and tick-borne disease agents. The geographic distribution of both arthropod vectors and the pathogens they transmit continues to expand.

METHODS

To describe the current geographic distribution and prevalence of antigen of Dirofilaria immitis and antibody to Borrelia burgdorferi, Ehrlichia spp., and Anaplasma spp. in dogs, we summarized over 144 million test results from 2013 to 2019, inclusive, by county, state, and region. Canine seroprevalence by state was compared to population-adjusted human reports of tick-borne diseases.

RESULTS

Results varied regionally, with D. immitis antigen and Ehrlichia spp. antibodies more frequently detected in the Southeast (2.6% and 5.2%, respectively) and antibody to B. burgdorferi and Anaplasma spp. most common in the Northeast (12.1% and 7.3%, respectively). Overall, percent positive test results to D. immitis decreased in the Southeast by 33.3% when compared to earlier summaries using the same strategy (from 3.9 to 2.6%). Geographic expansion of areas where dogs commonly test positive for Ehrlichia spp. was evident, likely because of a change in the test made in 2012 to allow detection of antibodies to E. ewingii concomitant with expansion of vector tick populations. Percent positive test results to Ehrlichia spp. increased in every region; this shift was particularly pronounced in the Southeast, where percent positive test results increased fourfold (from 1.3 to 5.2%). Continued geographic expansion of B. burgdorferi and A. phagocytophilum was apparent in the Northeast, Midwest, and Upper South, although canine seroprevalence of antibody to B. burgdorferi was much lower than prior surveys in many Lyme-endemic areas. Annual reports of human cases of Lyme disease, ehrlichiosis, and anaplasmosis were associated with percent positive canine results by state for the three tick-borne disease agents (R2 = 0.812, 0.521, and 0.546, respectively). Within endemic areas, percent positive test results for all three tick-borne agents demonstrated evidence of geographic expansion.

CONCLUSIONS

Large scale analysis of results from screening dogs in practice for evidence of vector-borne infections, including those with zoonotic importance, continues to be a valuable strategy for understanding geographic trends in infection risk over time.

[Compliance of dog and cat owners in preventive health care]

Regular preventive health care is an essential part of our pets' health and quality of life. Preventive healthcare appointments can result in the prevention of disease development as well as lead to the detection and subsequent treatment of existing health problems at an early stage. In order to achieve optimal health care, the owners' compliance is of most importance in addition to the veterinary advice. However, dog and cat owners often seem to be unaware of the necessity for preventive health care appointments, often as a result of poor communication by the veterinarian. Educational conversations concerning the necessity of regular preventive health examinations are therefore essential. Communication is one of the key factors in building an owner-veterinarian relationship. Veterinarians are advised to invest sufficient time for communication, be aware of their verbal and non-verbal statements, and enable the owner to participate in treatment decisions. Older animals are presented less often for preventive health care appointments than younger animals, although the prevalence of age-related and chronic diseases increases with age. Owners should therefore be informed on the fact that early detection and treatment of these diseases increases their animals' health and survival. Cats are seen less frequently in preventive health care than dogs; many owners are not aware of the characteristics of cats tending to hide signs of disease. Another reason lies in the fact that many cats are stressed by being captured and transported in addition to the visit in the veterinary practice itself. Veterinarians therefore should educate cat owners concerning stress-reducing transportation measures and design their practice in a more cat-friendly fashion. Compliance can also be influenced positively by appropriate practice management, such as offering monthly instalment payments, establishing annual preventive care plans, as well as regular re-scheduling strategies. In addition to enhancing the animals' health, this can also result in increased owner satisfaction.

Ixodes spp. from Dogs and Cats in the United States: Diversity, Seasonality, and Prevalence of Borrelia burgdorferi and Anaplasma phagocytophilum

Ixodes spp. are commonly found on dogs and cats throughout the world. In the eastern United States, 16S rDNA sequence of Ixodes scapularis, the predominant species, reveals two clades-American and Southern. To confirm the species and clades of Ixodes spp. ticks submitted from pets, we examined ticks morphologically and evaluated 16S rDNA sequence from 500 ticks submitted from 253 dogs, 99 cats, 1 rabbit, and 1 ferret from 41 states. To estimate pathogen prevalence, flaB of Borrelia burgdorferi (Bb) sensu stricto and 16S rDNA of Anaplasma phagocytophilum (Ap) were amplified and sequenced. Most Ixodes spp. from the Northeast (n = 115/115; 100%) and the Midwest (n = 77/80; 96.3%) were I. scapularis, American clade. Borrelia spp. were identified in 34 of 192 (17.8%) and Ap in 5 of 192 (2.6%) I. scapularis. Two Ixodes cookei and one Ixodes texanus were identified from Ohio, Illinois, and Michigan. In contrast, 156 of 261 (59.8%) Ixodes spp. from the Southeast were I. scapularis, American clade; 86 of 261 (33.0%) were I. scapularis, Southern clade; 9 of 261 (3.4%) were Ixodes affinis; and 10 of 261 (3.8%) were I. cookei. Southern clade was significantly more common in Florida and less common in the upper South (p < 0.0001). One I. scapularis (1/242; 0.4%) from the Southeast (Kentucky) tested positive for Bb and 6 of 242 (2.5%) were positive for Ap. In the West, most (34/44; 77.3%) Ixodes spp. were Ixodes pacificus, with Ixodes angustus (n = 6) submitted from dogs in Alaska, Washington, and Oregon and Ixodes haerlei (n = 4) preliminarily identified from a dog in Montana. Pathogens were not detected in any ticks from the West. Although I. scapularis, American clade, predominated in the Northeast and Midwest, additional Ixodes spp. were found on dogs and cats in other regions and pathogens were less commonly detected. The role of less common Ixodes spp. as disease vectors, if any, warrants continued investigation.

Detection of gastrointestinal parasitism at recreational canine sites in the USA: the DOGPARCS study

BACKGROUND

The rapid growth in off-leash dog parks provides opportunity for canine socialization activities but carries risk of exposure to intestinal parasites. This study assessed the prevalence of these infections in dogs visiting off-leash dog parks.

METHODS

Fresh defecations were collected from dogs visiting parks in 30 metropolitan areas across the USA. Samples were analyzed by coproantigen immunoassay (CAI) (Fecal Dx® and Giardia Test, IDEXX Laboratories, Inc.) and zinc sulfate centrifugal flotation (CF). Owners responded to a questionnaire on their dog's signalment and use of heartworm/intestinal parasite control medications (HWCM).

RESULTS

Samples were examined from 3006 dogs, 87.9% aged at least 12 months, visiting 288 parks. At least one intestinal parasite was detected in 622 (20.7%) samples, nematodes in 263 (8.8%), with hookworms, whipworms and ascarids in 7.1, 1.9 and 0.6% of samples, respectively. A sample positive for one or more intestinal parasites was found in 245 (85.1%) parks, with nematodes found in 143 (49.7%). Combined, CAI and CF detected 78.4% more intestinal nematode infections than CF alone. Hookworm and whipworm infections were detected in all age groups, but ascarids were only detected in dogs less than 4 years-old. Approximately 42% of dogs aged less than 1 year were positive for nematodes or Giardia. Based on owner reports, HWCM was current for 68.8% of dogs, dogs previously diagnosed with intestinal parasitism were more likely to be receiving a HWCM than those without such history, and a significantly lower (P = 0.0003) proportion of dogs receiving a HWCM were positive for intestinal nematodes compared with those not on such medication.

CONCLUSIONS

Intestinal parasites, the most common of which were Giardia, Ancylostoma caninum and Trichuris vulpis, were found in 20% of dogs and 85% of dog parks across the USA. Enhanced detection of canine intestinal parasitism was achieved by combining CF and CAI. Canine intestinal parasites are common across the USA and dog health can be improved by regular testing of fecal samples and routine administration of medications effective against the most common infections.

Haemaphysalis longicornis, the Asian longhorned tick, from a dog in Virginia, USA

The Asian longhorned tick, Haemaphysalis longicornis, was only recently recognized in North America and has since been identified on a wide range of domestic and wild animal hosts in multiple states throughout the eastern United States. An H. longicornis nymph was submitted for identification from a dog in central Virginia, USA. Identification was made using standard keys and confirmed molecularly. No products are currently FDA label-approved as effective for H. longicornis in the USA; however, many acaricides commercially available in the United States are known to be effective against H. longicornis in other areas of the world where this tick is endemic. Veterinarians should be aware H. longicornis can commonly be found infesting dogs, cats, livestock, and wildlife, and should continue recommending year-round tick prevention for all pets and routine monitoring for tick-borne infections.

Prevalence of intestinal parasites in fecal samples and estimation of parasite contamination from dog parks in central Oklahoma

Domestic dogs commonly harbor intestinal parasites in Oklahoma and throughout the world. We tested fecal samples from dog parks to determine the prevalence of intestinal parasites and reported use of parasite control in park-attending dogs and assess potential health risks posed by fecal contamination of public dog parks in this region. Fecal samples (n = 359) were collected from five public access dog parks in central Oklahoma from February to July 2019. Fecal samples were collected immediately after defecation with a corresponding canine lifestyle questionnaire completed by the owner (n = 134) or collected from the ground from unknown animals to assess potential parasitic contamination of the parks (n = 225). Sugar centrifugal flotation and saline sedimentation were performed on all samples for parasite diagnosis. Group comparisons were conducted using the Χ² test and 95% binominal confidence intervals were calculated for each proportion. One or more parasites were identified in 24.0% (86/359) of samples, including 38/134 (28.4%) fresh samples and 48/225 (21.3%) environmental samples; 6.1% were co-infected. Parasites detected included Ancylostoma spp. (14.5%), Trichuris vulpis (6.7%), Cystoisospora spp. (3.6%), Sarcocystis spp. (1.7%), and Giardia duodenalis (1.4%). A small number of samples had Cryptosporidium spp., Toxocara canis, Alaria sp., Taeniidae eggs, or Heterobilharzia americana. Owners reported 73.1% (98/134) of dogs were maintained on heartworm preventive. Intestinal nematodes, but not all parasites, were significantly less commonly detected in dogs reportedly on heartworm preventive (11.2%) compared to dogs not on heartworm preventive (27.8%; P = .0194). These data suggest dogs and people visiting dog parks are at risk of parasite exposure and that an owner-reported history of heartworm preventive use is associated with decreased prevalence of intestinal nematodes.