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Fixation and demineralization protocols for bone marrow (BM) across diagnostic laboratories are not standardized. How different protocols affect histomorphology and DNA amplification is incompletely understood. In this study, 2 fixatives and 3 demineralization methods were tested on canine BM samples. Twenty replicate sternal samples obtained within 24 hours of death were fixed overnight in either acetic acid-zinc-formalin (AZF) or 10% neutral-buffered formalin (NBF) and demineralized with formic acid for 12 hours. Another 53 samples were fixed in AZF and demineralized with hydrochloric acid for 1-hour, formic acid for 12 hours, or ethylenediamine tetraacetic acid (EDTA) for 24 hours. Histologic sections were scored by 4 raters as of insufficient, marginal, good, or excellent quality. In addition, DNA samples extracted from sections treated with the different fixation and demineralization methods were amplified with 3 sets of primers to conserved regions of T cell receptor gamma and immunoglobulin heavy chain genes. Amplification efficiency was graded based on review of capillary electrophoretograms. There was no significant difference in the histomorphology scores of sections fixed in AZF or NBF. However, EDTA-based demineralization yielded higher histomorphology scores than demineralization with hydrochloric or formic acid, whereas formic acid resulted in higher scores than hydrochloric acid. Demineralization with EDTA yielded DNA amplification in 29 of 36 (81%) samples, whereas demineralization with either acid yielded amplification in only 2 of 72 (3%) samples. Although slightly more time-consuming and labor-intensive, tissue demineralization with EDTA results in superior morphology and is critical for polymerase chain reaction (PCR) amplification with the DNA extraction method described in this article.

Given the prevalence of pet ownership in homes, understanding and acknowledging the role of human-animal relationships within the family is critical. Many pet owners identify as “pet parents” and actively pamper their pets with human-grade food, have birthday parties, schedule play dates, and dress them up in clothes and accessories. More homes in the United States have pets than children. In this study, a sample of 332 dog owners from the United States, stratified according to age and sex, completed an online survey. This study used several instruments such as the CENSHARE pet attachment scale, guilt about dog-parenting scale, work-dog conflict scale, making-up behavior scale, and revised adult attachment scale. Correlation analyses and linear regressions were conducted to determine the nature of the relationships between the variables. As predicted, this study found that stronger pet attachment increased dog-parent guilt, work-dog conflict, and make-up behaviors. Moreover, those with an anxious attachment style were more likely to experience dog-parent guilt, also known as disenfranchised guilt. This parental type guilt is when parents feel that work or life demands interfere with their ability to fulfill their role as parents. Pet-parent guilt was similar to that found in parents with human children. Correlation analysis revealed no relationships of pet attachment with any demographic variables, which included sex, age, race, relationship status, household income, and education and parental status. These findings were consistent with a previous study revealing that pet parents who had a strong attachment to their pets experienced dog-parent guilt and work-dog conflict. In addition, this was the first study to examine dog-parent guilt, make-up behaviors, and human attachment styles. Perhaps utilizing a multi-system approach involving educators, mental health professionals, veterinarian professionals, advocates, and organizations can help pet parents feel validated and supported regarding their feelings of guilt. Building a support network for pet parents to connect with others who share similar experiences can validate their feelings and help those who feel isolated.

The Wnt signaling pathway is critical for normal embryonic development. Disruptions in the Wnt signaling pathway have been linked to neurological disorders. The RAPGEF5 protein is a partner in Wnt signaling and a RAPGEF5 3-bp insertion is associated with increased risk for idiopathic epilepsy in the Belgian shepherd dog. The 3-bp insertion risk variant introduces an alanine residue predicted to disrupt the protein. Wildtype and the risk variant RAPGEF5 cDNAs were cloned into green fluorescent protein (GFP) expression vectors and transfected into canine kidney cells. The cellular localization of each GFP-labeled RAPGEF5 protein was assessed. Variant RAPGEF5 protein was altered in its localization from that of the wildtype protein and rather than localized to the nucleus and cytoplasm as seen for the wildtype, it was predominantly found in the cytoplasm. Belgian shepherds with the risk variant for RAPGEF5 may have altered Wnt signaling due to modified intracellular localization which in turn could thereby contribute to the expression of idiopathic epilepsy.

PurposeSpontaneously occurring glioma in pet dogs is increasingly recognized as a valuable translational model for human glioblastoma. Canine high-grade glioma and human glioblastomas share many molecular similarities, including the accumulation of immunosuppressive regulatory T cells (Tregs) that inhibit anti-tumor immune responses. Identifying in dog mechanisms responsible for Treg recruitment may afford to target the cellular population driving immunosuppression, the results providing a rationale for translational clinical studies in human patients. Our group has previously identified C-C motif chemokine 2 (CCL2) as a glioma-derived T-reg chemoattractant acting on chemokine receptor 4 (CCR4) in a murine orthotopic glioma model. Recently, we demonstrated a robust increase of CCL2 in the brain tissue of canine patients bearing high-grade glioma.MethodsWe performed a series of in vitro experiments using canine Tregs and patient-derived canine glioma cell lines (GSC 1110, GSC 0514, J3T-Bg, G06A) to interrogate the CCL2-CCR4 signaling axis in the canine.ResultsWe established a flow cytometry gating strategy for identifying and isolating FOXP3+ Tregs in dogs. The canine CD4 + CD25high T-cell population was highly enriched in FOXP3 and CCR4 expression, indicating they are bona fide Tregs. Canine Treg migration was enhanced by CCL2 or by glioma cell line-derived supernatant. Blockade of the CCL2-CCR4 axis significantly reduced migration of canine Tregs. CCL2 mRNA was expressed in all glioma cell lines, and expression increased when exposed to Tregs but not CD4 + helper T-cells.ConclusionOur study validates CCL2-CCR4 as a bi-directional Treg-glioma immunosuppressive and tumor-promoting axis in canine high-grade glioma.

This study aimed to assess the French version of the Lexington Attachment to Pets Scale (LAPS) and to explore the factors influencing the attachment between French pet owners and their cats and dogs. Given the absence of a French tool to evaluate pet attachment, LAPS was translated into French using a rigorous back-translation method. An online survey was developed to assess LAPS scores, socio-demographic data, and owner characteristics, resulting in 1872 eligible responses. The French LAPS demonstrated strong reliability as well as good internal consistency and repeatability. Median LAPS scores were higher for dog owners (58.5) compared with cat owners (52.0), while individuals who owned both species showed significantly higher scores for their dogs than for their cats. Factors associated with higher attachment scores for owners of both species included the female gender of the owner, living without children, and lower educational background. This study reinforces the existing body of evidence about gender and pet type differences in terms of attachment and highlights the potential influence of social desirability bias. It provides valuable insights into the complexities of human-animal bonds in the French context and shows the influence of social standards on pet attachment.

Objective assessment of activity via accelerometry can provide valuable insights into dog health and welfare. Common activity metrics involve using acceleration cut-points to group data into intensity categories and reporting the time spent in each category. Lack of consistency and transparency in cut-point derivation makes it difficult to compare findings between studies. We present an alternative metric for use in dogs: the acceleration threshold (as a fraction of standard gravity, 1 g = 9.81 m/s2) above which the animals X most active minutes are accumulated (MXACC) over a 24-hour period. We report M2ACC, M30ACC and M60ACC data from a colony of healthy beagles (n = 6) aged 3-13 months. To ensure that reference values are applicable across a wider dog population, we incorporated labelled data from beagles and volunteer pet dogs (n = 16) of a variety of ages and breeds. The dogs normal activity patterns were recorded at 200 Hz for 24 hours using collar-based Axivity-AX3 accelerometers. We calculated acceleration vector magnitude and MXACC metrics. Using labelled data from both beagles and pet dogs, we characterize the range of acceleration outputs exhibited enabling meaningful interpretation of MXACC. These metrics will help standardize measurement of canine activity and serve as outcome measures for veterinary and translational research.

ObjectiveEvaluate whether total elbow replacement (TER) through a lateral approach is accurate and stable.Animals12 skeletally mature large-breed dog cadavers were used.MethodsLimb alignment, elbow joint motion, and collateral ligament laxity were evaluated preoperatively. The order of surgery (left or right) and the approach (lateral or medial) were randomly selected for TER in each dog. The other approach was used in the contralateral elbow. Intraoperative technical difficulties, duration of surgery, and anatomic complications were recorded. Limb alignment, elbow joint motion, collateral ligament laxity, and prosthetic component alignment were evaluated after surgery. Data were collected from June 11 to 15, 2023.ResultsThe duration of surgery using a lateral or medial approach did not differ (P = .499). Anatomic complications were not observed. The lateral approach resulted in 8° more elbow extension (P = .003), 1.58° less lateral collateral ligament constraint (P = .033), 2.80° less medial collateral ligament constraint (P = .002), 4.38° less frontal plane constraint (P = .004), 8° greater humeral component inclination (P = .033), and 5.6° greater radioulnar component varus (P = .001) than the medial approach. Varus of the radius, mechanical axis deviation, limb supination, elbow flexion, mediolateral humeral component and craniocaudal radioulnar component orientation did not differ among joints operated using a lateral or medial approach. In normal cadaveric elbows, a lateral approach for TER appears feasible, producing equivalent limb alignment, joint laxity, and joint motion to normal elbows and to TER placed using a medial approach.Clinical relevanceIn dogs, TER can be performed using a lateral surgical approach.

Genome-wide association studies (GWAS) in long-lived human populations have led to identification of variants associated with Alzheimer's disease and cardiovascular disease, the latter being the most common cause of mortality in people worldwide. In contrast, naturally occurring cancer represents the leading cause of death in pet dogs, and specific breeds like the Golden Retriever (GR) carry up to a 65% cancer-related death rate. We hypothesized that GWAS of long-lived GRs might lead to the identification of genetic variants capable of modifying longevity within this cancer-predisposed breed. A GWAS was performed comparing GR dogs ≥ 14 years to dogs dying prior to age 12 which revealed a significant association to ERBB4, the only member of the epidermal growth factor receptor family capable of serving as both a tumor suppressor gene and an oncogene. No coding variants were identified, however, distinct haplotypes in the 5'UTR were associated with reduced lifespan in two separate populations of GR dogs. When all GR dogs were analyzed together (n = 304), the presence of haplotype 3 was associated with shorter survival (11.8 years vs. 12.8 years, p = 0.024). GRs homozygous for haplotype 3 had the shortest survival, and GRs homozygous for haplotype 1 had the longest survival (11.6 years vs. 13.5 years, p = 0.0008). Sub-analyses revealed that the difference in lifespan for GRs carrying at least 1 copy of haplotype 3 was specific to female dogs (p = 0.009), whereas survival remained significantly different in both male and female GRs homozygous for haplotype 1 or haplotype 3 (p = 0.026 and p = 0.009, respectively). Taken together, these findings implicate a potential role for ERBB4 in GR longevity and provide evidence that within-breed canine lifespan studies could serve as a mechanism to identify favorable or disease-modifying variants important to the axis of aging and cancer.

Bacterial pneumonia can present in both dogs and cats as either acute or chronic disease, and clinical signs may suggest respiratory or systemic impairment. Aspiration pneumonia, a common form of disease, can be caused by esophageal or laryngeal disease, vomiting, or altered mentation, such as with CNS disease or general anesthesia. Bacterial pneumonia can also develop due to inhaled airway foreign bodies, reduced local immune function, or impaired clearance of respiratory secretions. Rapid identification of the etiology and associated risk factors for pneumonia can help veterinarians develop a targeted therapeutic plan and prevent recurrence of disease.

(1) Background: Muscle hypertrophy, swallowing disorders, and gait abnormalities are clinical signs common to many muscle diseases, including muscular dystrophies, non-dystrophic myotonias, genetic myopathies associated with deficiency of myostatin, and acquired inflammatory myopathies. Here, we investigated underlying causes of this triad of clinical signs in four young French bulldogs via muscle histopathology coupled with whole genome and Sanger sequencing. (2) Methods: Dogs were evaluated by veterinary clinical internists and neurologists, and biopsies were obtained for histopathological diagnosis. DNA was submitted for whole genome sequencing, followed by bioinformatics evaluation and confirmation of variants via Sanger sequencing in two cases. (3) Results: Two novel variants were identified. The first, found in two related French bulldogs, was a homozygous variant in the chloride channel gene CLCN1 known to cause non-dystrophic congenital myotonia, and the second, found in an unrelated French bulldog, was a heterozygous variant in the cAMP phosphodiesterase gene PDE4C, which is the major phosphodiesterase expressed in skeletal muscle and may play a role in decreasing muscle atrophy. An underlying molecular basis in one other case has not yet been identified. (4) Conclusions: Here, we identified two novel variants, one in the CLCN1 and one in the PDE4C gene, associated with clinical signs of muscle hypertrophy, dysphagia, and gait abnormalities, and we suggested other bases of these phenotypes in French bulldogs that are yet to be discovered. Identification of genes and deleterious variants associated with these clinical signs may assist breeders in improving the overall health of this very popular breed and may lead to the identification of new therapies to reverse muscle atrophy in people and animals with neuromuscular diseases.

Idiopathic epilepsy (IE) has been known to be inherited in the Belgian Tervuren for many decades. Risk genotypes for IE in this breed have recently been identified on Canis familiaris chromosomes (CFA) 14 and 37. In the current study, the allele frequencies of these loci were analyzed to determine whether dog breeders had employed a purposeful selection against IE, leading to a reduction in risk-associated allele frequency within the breed over time. The allele frequencies of two generational groupings of Belgian Tervuren with and without IE were compared. Allele frequencies for risk-associated alleles on CFA14 were unchanged between 1985 and 2015, whereas those on CFA37 increased during that time in the control population (p < 0.05). In contrast, dogs with IE showed a decrease (p < 0.05) in the IE risk-associated allele frequency at the CFA37 locus. Seizure prevalence in the Belgian Tervuren appears to be increasing. These results suggest that, despite awareness that IE is inherited, selection against IE has not been successful.

BACKGROUND: Recurrent bacterial cystitis, often referred to as recurrent urinary tract infection (UTI), can be difficult to manage and alternative treatments are needed. HYPOTHESIS/OBJECTIVE: Intravesicular administration of asymptomatic bacteriuria (ASB) E. coli 212 will not be inferior to antimicrobial treatment for the management of recurrent UTI in dogs. ANIMALS: Thirty-four dogs with >1 UTI in the 12 months before presentation. METHODS: All dogs were deemed normal otherwise based on absence of abnormalities on physical examination, CBC, serum biochemical panel, and abdominal ultrasonography. Dogs were randomized to 1 of 2 treatment groups: Group 1 antimicrobials for 7 days or group 2 intravesicular administration of ASB E. coli 212. Owners were provided a voiding questionnaire regarding their dogs clinical signs, which was completed daily for 14 days to assess clinical cure. Dogs were examined on days 7 and 14 to assess clinical cure, and urine specimens were submitted for urinalysis and bacterial culture. RESULTS: Clinical cure rates for ASB E. coli 212-treated dogs were not inferior to 7 days of antimicrobial treatment with a 12% margin of difference to determine non-inferiority. No significant difference was found between the treatment groups on days 7 and 14 in the proportion of dogs achieving ≥50% or ≥75% reduction in their clinical score compared with baseline. CONCLUSIONS AND CLINICAL IMPORTANCE: These data suggest that intravesicular administration of ASB E. coli 212 is not inferior to antimicrobials for the treatment of recurrent UTI in dogs. This biotherapeutic agent could help alleviate the need for antimicrobials for some dogs with recurrent UTI, improving antimicrobial stewardship.

In prostate cancer (PCa), androgens upregulate tumorigenesis, whereas in benign tissue, the revival of androgen receptor (AR) signaling suppresses aggressive behaviors, suggesting therapeutic potential. Dogs, natural PCa models, often lack AR in PCa. We restored AR in dog PCa to investigate resultant characteristics. Three AR-null canine PCa lines (1508, Leo, 1258) were transfected with canine wild-type AR and treated with dihydrotestosterone (DHT). In 1508, AR restoration decreased clonogenicity (p = 0.03), viability (p = 0.004), migration (p = 0.03), invasion (p = 0.01), and increased expression of the tumor suppressor NKX3.1, an AR transcriptional target (p = 0.001). In Leo, AR decreased clonogenicity (p = 0.04) and the expression of another AR transcriptional target FOLH1 (p < 0.001) and increased the expression of NKX3.1 (p = 0.01). In 1258, AR increased migration (p = 0.006) and invasion (p = 0.03). Epithelial-mesenchymal transition (EMT) marker (Vimentin, N-cadherin, SNAIL1) expression increased with AR restoration in Leo and 1258 but not 1508; siRNA vimentin knockdown abrogated AR-induced 1258 migration only. Overall, 1508 showed AR-mediated tumor suppression; AR affected proliferation in Leo but not migration or invasion; and EMT and AR regulated migration and invasion in 1258 but not proliferation. This study highlights the heterogeneous nature of PCa in dogs and cell line-specific effects of AR abrogation on aggressive behaviors.

Dogs are susceptible to a diverse spectrum of dermatologic conditions, several of these skin disorders are analogous to dermatologic conditions occurring in humans. Pool toes appears on the plantar surface of the feet and toes; it is an aquatic pool-associated frictional dermatosis that results from repeated rubbing of the feet and toes against the rough cement at the bottom of the pool or its border. A frictional dermatosis that can develop on the uncalloused paw pads of puppies, resulting from repeated rubbing of the paws against ambient temperature, not heated, paved road is pavement paws. Neither pool toes nor pavement paws result from contact with a hot surface; these dermatoses are distinctive from beach feet, a thermal-associated superficial burn to the skin resulting from the hot temperature of the sand that contacts that the plantar feet and toes. In conclusion, similar to pool toes, the pathogenesis of pavement paws is a frictional dermatosis that can develop on the uncallused paw pads of puppies resulting from repeated rubbing of the paws against ambient temperature, not heated, pavement.

INTRODUCTION: The objective of this study was to investigate the diagnostic potential of bacterial biomarkers by comparing the performance of molecular detection assays with clinical assessments of dogs oral health performed by veterinarians. METHODS: Supragingival and subgingival plaque samples were collected from 127 client-owned dogs, pre-booked for procedures under general anesthesia, visiting veterinary practices in the United States. DNA was extracted and bacterial biomarkers quantified using quantitative polymerase chain reaction. Gingivitis and periodontitis were recorded by a trained clinician using the Weighted Gingivitis Periodontitis Score which involved assessing the buccal surfaces of 18 teeth while under general anesthesia. Intraoral dental radiographs of the left and right mandibular first molar teeth were also obtained. These data were then used to establish the diagnostic performance of the molecular assay to detect periodontitis. RESULTS: An initial conscious, visual oral examination performed by the veterinarian identified 67.7% of dogs as having periodontitis, but examination under general anesthesia indicated a higher proportion (86.6%). Analysis of supragingival plaque samples collected by veterinarians from conscious and unconscious dogs demonstrated the assay had an accuracy of 77.7 to 80.9%, a sensitivity of 77.6 to 81.0%, and a specificity of 80.0%. DISCUSSION: Use of this molecular screening tool in conscious dogs has the potential to improve early periodontal disease detection and support veterinary decision making, ultimately improving the oral health of dogs and consequently their quality of life.

The first International Conference on Unconventional Animal Models of Alzheimers Disease and Aging (UAMAA) took place on December 13-16, 2023, in Santiago, Chile. The Alzheimers disease (AD) research field is currently in search for new and unconventional models that could hold greater translational potential than transgenic mouse models. Thus this UAMAA conference is timely and significant. The event consisted of 6 sessions with talks from 28 world-class scientists from all over the world. These animal models of interest include the degu (Octodon degu), the dog (Canis familiaris), and certain species of nonhuman primates that may better recapitulate neuropathology and cognitive impairments in human AD. Our conference has provided a formal forum to discuss and highlight new research directions, alternative animal models, and innovative approaches for the AD and aging research field.

INTRODUCTION: Dosing recommendations for hydromorphone intravenous constant rate infusion (IV CRI) are derived from simulations following IV bolus administration. While this extrapolated dose regimen has been described clinically, pharmacokinetics (PK) of hydromorphone infusions in dogs are not yet described. The study objective was to describe the PK of hydromorphone in healthy dogs receiving an IV bolus followed by an IV CRI for 48 h. METHODS: A prospective, experimental study was performed involving the administration of hydromorphone (0.1 mg/kg IV bolus then IV CRI 0.01 mg/kg/h over a 48 h period) to 6 healthy Beagle dogs. Blood samples were collected at 16 time points between 0 and 58 h relative to the initial bolus. Plasma hydromorphone concentrations were analyzed by high pressure liquid chromatography with tandem mass spectrometry detection. Pharmacokinetic parameter estimates were obtained with compartmental methods using commercially available software. RESULTS: A two-compartment model with first order elimination was used. At the end of the infusion, median (range) plasma hydromorphone concentrations were 6.8 (5.5-19.6) ng/mL. The median total body clearance was 30.4 (19.8-36.7) mL/min/kg; volume of distribution at steady state was 4.5 (3.2-7.8) L/kg; and terminal elimination half-life was 11.2 (7.6-24.3) h. CONCLUSION: Hydromorphone (0.1 mg/kg IV bolus then IV CRI of 0.01 mg/kg/h) maintained steady-state plasma concentrations above the minimum human analgesic target in healthy Beagle dogs with minimal side effects. Further studies are needed to determine the effective plasma concentrations of hydromorphone in painful dogs.

Clinicopathologic data in dogs with prostate cancer (PCa) may aid in the differentiation between tumor types and subsequent treatment decisions; however, these data are often unreported. Demographic, clinicopathologic, cytologic, histologic and survival data from dogs with primary prostatic adenocarcinoma (PRAD) (n = 56) and primary prostatic transitional cell carcinoma (P-TCC) (n = 74) were acquired from a tertiary veterinary teaching hospital from 1992 to 2022. Red blood cell distribution width (RDW) to albumin ratio (RAR) was evaluated for diagnostic utility in differentiating between PRAD and P-TCC. Sections from PRAD tumors (n = 50) were stained for androgen receptor (AR) expression, and laboratory data were compared between AR positive (AR+) and AR negative (AR-) groups. RDW was increased in PRAD, while albumin was decreased (p < 0.05). P-TCC was associated with Melamed-Wolinska bodies (MWB) and necrosis on cytology (p < 0.05). RAR had acceptable diagnostic utility in the differentiation of PCa tumors (AUC = 0.7; p < 0.05). Survival rates and metastases were equivocal. AR+ and AR- PRAD tumors did not differ in clinicopathologic data or survival (p > 0.05). In conclusion, hypoalbuminemia was significantly associated with PRAD and decreased survival, while MWB and necrosis were significantly associated with P-TCC on cytology. These clinicopathologic data may help clinicians differentiate between these tumors ante mortem to guide appropriate treatment and intervention.

Background Objectives Animals Methods Results Conclusions and Clinical Importance Protothecosis in dogs is a rare, yet emerging disease, distinguished by its often‐aggressive clinical course and high fatality rate. Our study was conducted to enhance treatment protocols for affected dogs by better understanding the genetic diversity and drug resistance patterns of Prototheca species.To identify species and drug susceptibility profiles of an international collection of 28 Prototheca strains isolated from cases of protothecosis in dogs.None.Retrospective study. Species‐level identification was made for isolates from 28 dogs in 6 countries by molecular typing with the partial cytb gene as a marker. For the determination of minimum inhibitory concentrations (MICs) and minimum algicidal concentrations (MACs), the Clinical Laboratory Standards Institute (CLSI) protocol (M27‐A3) was used.Prototheca bovis was the most prevalent species, accounting for 75% (21/28) of the cases, followed by P. wickerhamii (18%; 5/28) and P. ciferrii (7%; 2/28). Of the 6 drugs tested, efinaconazole (EFZ) was the most potent in vitro, with its median MIC and MAC values equal to 0.125 mg/L. The lowest activity was found for fluconazole (FLU), with MIC and MAC medians of 48 mg/L and 64 mg/L, respectively.Our study identifies P. bovis as the species that most frequently causes protothecosis in dogs, which suggests the possibility of cross‐species infection from other animals, especially cows. Additionally, it indicates that EFZ could be used in the treatment of infection in the colon. [ABSTRACT FROM AUTHOR]

The glabrous skin of the rhinarium (naked nose) of many mammalian species exhibits a polygonal pattern of grooves that retain physiological fluid, thereby keeping their nose wet and, among other effects, facilitating the collection of chemosensory molecules. Here, we perform volumetric imaging of whole-mount rhinaria from sequences of embryonic and juvenile cows, dogs, and ferrets. We demonstrate that rhinarial polygonal domains are not placode-derived skin appendages but arise through a self-organized mechanical process consisting of the constrained growth and buckling of the epidermal basal layer, followed by the formation of sharp epidermal creases exactly facing an underlying network of stiff blood vessels. Our numerical simulations show that the mechanical stress generated by excessive epidermal growth concentrates at the positions of vessels that form rigid base points, causing the epidermal layers to move outward and shape domes—akin to arches rising against stiff pillars. Remarkably, this gives rise to a larger length scale (the distance between the vessels) in the surface folding pattern than would otherwise occur in the absence of vessels. These results hint at a concept of "mechanical positional information" by which material properties of anatomical elements can impose local constraints on an otherwise globally self-organized mechanical pattern. In addition, our analyses of the rhinarial patterns in cow clones highlight a substantial level of stochasticity in the pre-pattern of vessels, while our numerical simulations also recapitulate the disruption of the folding pattern in cows affected by a hereditary disorder that causes hyperextensibility of the skin. [Display omitted] • Rhinarial polygonal domains are not placode-derived but mechanically self-organized • The rhinarial skin pattern is mechanically coupled with underlying blood vessels • Epidermal domes rise against stiffer blood vessels—like arches against pillars • Rhinarial folds are as variable among cow clones as among unrelated individuals Dagenais et al. demonstrate that the characteristic polygonal folding patterns on the noses of many mammalian species, such as dogs, ferrets, and cows, emerge via a peculiar self-organizational process involving mechanical positional information encoded by the spatial distribution of stiffness in adjacent tissues. [ABSTRACT FROM AUTHOR]

This case report details the diagnosis and treatment of dentinogenesis imperfecta in a 6-year-old neutered male Labrador, presenting without concurrent osteogenesis imperfecta. Diagnostic modalities, including radiographs, CT imaging, and histopathological examination, are reviewed in conjunction with the latest literature on canine dentinogenesis imperfecta. This patient presented at a more advanced age than typically reported cases. The clinical history, as provided by referring veterinarians, documented fractured deciduous teeth with delayed exfoliation. By 10 months of age, the patient's permanent dentition exhibited a translucent appearance and structural anomalies. Upon presentation to Eastcott Referrals the patient was experiencing significant oral pain and exhibited generalised coronal wear with yellow/brown intrinsic discolouration. CT imaging revealed that all teeth had endodontic disease and associated apical periodontitis, with varied root canal widths indicating that teeth succumbed to endodontic disease at different time points. The treatment protocol involved staged full-mouth extractions, resulting in the complete resolution of clinical symptoms. This case underscores the importance of early diagnosis and intervention in managing dentinogenesis imperfecta in dogs. [ABSTRACT FROM AUTHOR]

A 9-month-old female Jack Russell Terrier was referred because of two episodes of suspected syncope. Echocardiography revealed a large, isolated mid-muscular ventricular septal defect (7 mm) with bidirectional shunting. A diagnosis of Eisenmenger syndrome and erythrocytosis (68.5% of hematocrit) was made and sildenafil therapy (0.5 mg/Kg twice daily) was initiated. Regular follow-up examinations were performed and Sildenafil therapy was gradually increased based on changes in clinical signs, packed cell volume and heart rate. The dog's clinical conditions have been stable without the need of phlebotomy for 4 years and 6 months, until April 2021 (month 74) (about 7 years of survival) when the dog had 80% of hematocrit and signs of hyperviscosity syndrome. The dosage of administered sildenafil reached gradually 6 mg/Kg DIE (2 mg/Kg three times a daily) in June 2022. Lastly, in November 2023 a closed pyometra was diagnosed and the dog was hospitalized and operated. The major concerns in the peri-operative period were hypotension and the profound hypoxemia, but the dog was discharged and recovered normal activity in approximately 11 days. This report describes the long-term management with sildenafil citrate of Eisenmenger syndrome secondary to a muscular ventricular septal defect with right-to-left shunting in a dog. Sildenafil therapy was always well tolerated with no side effects reported, even at higher dosage and drastically reduced the need for phlebotomy. [ABSTRACT FROM AUTHOR]

Background: DNA methylation is a covalent bond modification that is observed mainly at cytosine bases in the context of CG pairs. DNA methylation patterns reflect the status of individual tissues, such as cell composition, age, and the local environment, in mammals. Genetic factors also impact DNA methylation, and the genetic diversity among various dog breeds provides a valuable platform for exploring this topic. Compared to those in the human genome, studies on the profiling of methylation in the dog genome have been less comprehensive. Results: Our study provides extensive profiling of DNA methylation in the whole blood of three dog breeds using whole-genome bisulfite sequencing. The difference in DNA methylation between breeds was moderate after removing CpGs overlapping with potential genetic variation. However, variance in methylation between individuals was common and often occurred in promoters and CpG islands (CGIs). Moreover, we adopted contextual awareness methodology to characterize DNA primary sequences using natural language processing (NLP). This method could be used to effectively separate unmethylated CGIs from highly methylated CGIs in the sequences that are identified by the conventional criteria. Conclusions: This study presents a comprehensive DNA methylation landscape in the dog blood. Our observations reveal the similar methylation patterns across dog breeds, while CGI regions showed high variations in DNA methylation level between individuals. Our study also highlights the potential of NLP approach for analyzing low-complexity DNA sequences, such as CGIs. [ABSTRACT FROM AUTHOR]

L-Asparaginase (ASNase) exerts its main anticancer activity by depleting L-Asparagine (Asn). In dogs with lymphomas, ASNase is commonly administered intramuscularly or subcutaneously and incorporated in multiagent protocols. The goal of this study is to assess plasma asparagine depletion and ASNase activity after intravenous administration of ASNase. A secondary goal was to investigate the toxicity and clinical response after intravenous infusion of high-dose ASNase. The study included ten dogs with naïve multicentric lymphoma. All dogs were immunophenotyped, staged, and followed to death. ASNase was administered intravenously at a dose of 3000 IU/kg on a Monday-Wednesday-Friday schedule. ASNase activity and Asn concentration were assessed on days 1, 3, and 5, before and after infusion, and on day 21. Clinical response and toxicity were assessed on weeks 2, 6, and 10, and then every 4 weeks until relapse. Plasma ASNase activity was sufficient to induce and maintain Asn depletion after and between each administration. The activity at day 21 was below detection in 8/10 dogs, and Asn was still depleted in 4/10 dogs. The ORR was 60% (respectively 40%CR and 20%PR). The median TTP was 31 days (95% CI 0–70). All dogs underwent rescue treatment with a multiagent protocol (8 CHOP and 2 LOPP). The median TTP after starting a rescue was not reached after 392 days. Mild gastrointestinal toxicity occurred in 30% of dogs, while hematologic toxicity or hypersensitivity reactions did not occur. ASNase activity and depletion of Asn were clinically adequate. The clinical efficacy was comparable with previous literature. The intravenous infusion of high-dose ASNase was well tolerated with only mild and self-limiting toxicity. [ABSTRACT FROM AUTHOR]

A 13-year-old, spayed, female mixed breed dog that had previously undergone mastectomy and ovariohysterectomy at our institution was referred to the nuclear medicine department for metastasis evaluation following surgery. 18F-deoxy-2-D-glucose positron emission tomography/computed tomography (18F-FDG PET-CT) was performed and a soft-tissue mass was observed in the abdominal cavity. The characteristics of the abdominal mass were assessed and screening for metastasis was done with follow-up 18F-FDG PET scans. Uptake of 18F-deoxy-2-D-glucose was higher in the peripheral region and lower in the center of the abdominal mass. Exploratory laparotomy was performed, and the removed abdominal mass was consistent with a gossypiboma, which is a retained surgical sponge composed of non-absorbable material with cotton matrix. This case report describes the characteristics of 18F-FDG PET-CT imaging in a dog with an abdominal gossypiboma, which has not been reported in the veterinary literature before. [ABSTRACT FROM AUTHOR]

Background: Accurate assessment of intravascular volume is critical for precise fluid prescription. In people, bedside or point of care ultrasound is used to measure the inferior vena cava, with or without paired aortic measurement, to estimate intravascular volume. Objective: To determine if point of care ultrasound measurement of the caudal vena cava (CVC) diameter or the CVC diameter to the abdominal aorta (Ao) diameter (CVC:Ao) at the paralumbar view are associated with changes in intravascular volume, mean arterial pressure (MAP), or cardiac output in normovolemic and hypovolemic dogs. Animals: 8 purpose-bred dogs. Methods: Pressure-targeted hemorrhagic shock was induced in purpose-bred dogs under general anesthesia. Dogs were exsanguinated to a mean arterial pressure of 40 mmHg, or a maximum 60% blood volume lost, then auto-transfused shed blood. At a left paralumbar view, longitudinal plane measurements of the abdominal CVC diameter and aortic diameter were obtained. Measurements were performed at 4 timepoints: baseline under anesthesia (TP1), after hemorrhagic shock was induced (TP2), after ½ of shed blood had been re-transfused (TP3), and post-resuscitation with completed re-transfusion (TP4). Additional variables collected included cardiac output using thermodilution and arterial blood pressure. Results: CVC:Ao was not significantly different between timepoints and was not associated with changes in CO (p = 0.28) or MAP (p = 0.50). CVC diameter was significantly different between baseline (TP1) and hemorrhagic shock (TP2). CVC diameter was significantly different at TP2 compared to TP1 after controlling for the effect of CO (p = 0.03) and MAP (p = 0.001). Aortic diameter was also significantly different at TP2 (p = 0.002, p = 0.001) and TP3 (p = 0.023, p = 0.017) compared to TP1 after controlling for CO and MAP. Conclusions and clinical importance: Obtaining point of care ultrasound images for CVC:Ao measurement was feasible. With a marked decrease in intravascular volume, both CVC and Ao diameter decreased, resulting in an unchanged CVC:Ao. Despite changes in CVC and Ao diameters, these changes were not associated with measured changes in CO, emphasizing that CO is not a direct estimate of intravascular volume and is affected by many compensatory mechanisms. Additional studies are needed to determine the most accurate method for bedside measurement of intravascular volume status. [ABSTRACT FROM AUTHOR]

Pharmaceutical companies routinely screen compounds for hemodynamics related safety risk. In vitro secondary pharmacology is initially used to prioritize compounds while in vivo studies are later used to quantify and translate risk to humans. This strategy has shown limitations but could be improved via the incorporation of molecular findings in the animal-based toxicological risk assessment. The aim of this study is to develop a mathematical model for rat and dog species that can integrate secondary pharmacology modulation and therefore facilitate the overall pre-clinical safety translation assessment. Following an extensive literature review, we built two separate models recapitulating known regulation processes in dogs and rats. We describe the resulting models and show that they can reproduce a variety of interventions in both species. We also show that the models can incorporate the mechanisms of action of a pre-defined list of 50 pharmacological mechanisms whose modulation predict results consistent with known pharmacology. In conclusion, a mechanistic model of hemodynamics regulations in rat and dog species has been developed to support mechanism-based safety translation in drug discovery and development. [ABSTRACT FROM AUTHOR]

Purpose Animals Studied Procedures Results Conclusions To determine the load at failure of canine intact cadaveric eyes and to describe the anatomic location and length of the rupture following external compression.Sixty‐six canine cadaveric globes.Globes were subjected to an axial force impacting the cornea or equator using a commercially available mechanical testing unit. Following rupture, eyes were inspected to document the anatomical site and length of rupture.The mean ± SD force necessary to induce scleral rupture was 310 ± 120 N OD and 294 ± 113 N OS. Increasing body weight (OD p = .000015, OS p = .0074) as well as cranial‐to‐caudal (OD p = .000045, OS p = .0075) and medial‐to‐lateral (OD p = .00027, OS p = .0083) globe diameter were associated with a higher force necessary to induce rupture. The median (25%, 75%) length of the scleral rupture was 8.5 (7.0, 11.0) mm OS and 10 (7.0, 12.5) mm OD. The median location was 8.0 (5.0, 10.0) mm posterior to the limbus at the most cranial extent OS and 6.5 (3.3, 10.0) mm OD. Rupture orientation in relation to the limbus was perpendicular (n = 35), parallel (n = 13), or other (n = 16). Globe laterality (i.e., OD or OS), sex, and age did not have a significant influence on the force necessary to induce rupture (p > .05).Following external compression, the canine globe frequently ruptures in a region approximating the equator extending 1 cm posteriorly, which may not be readily apparent on clinical examination. [ABSTRACT FROM AUTHOR]

Introduction: The response to medical management of young dogs with osteoarthritis (OA) associated pain has not been evaluated. Using an open-label design, the effectiveness, over a 4-month period, of standardized management (grapiprant/fish oil/exercise) for treating OA pain in young dogs was evaluated. Methods: Included dogs were 9 months-4 years of age; ≥3.6 kg body weight; had ≥1 appendicular joint with radiographic OA and obvious joint pain; had a Liverpool Osteoarthritis in Dogs (LOAD) score of ≥5. The non-steroidal anti-inflammatory piprant (grapiprant) was given at the recommended dose daily, omega-3 fatty acid supplementation was initiated at 100 mg/kg and then increased to 200 mg/kg daily, and leash exercise was gradually increased to a target of 60 min daily. Client-reported outcome measures (CROMs) and force plate gait analysis were collected at baseline and monthly for 4 months. The index limb was defined as the most severely affected limb at baseline. Results: Forty-eight dogs were enrolled (mean ± SD age of 30.7 ± 10.7 months). Hips, elbows, and stifles were commonly affected. Medication and supplement compliance was excellent (≥95% of target administered), and treatments were well-tolerated. CROMs showed significant improvement over time and at each time point. Overall, peak vertical force (PVF) increased significantly (<0.001), and vertical impulse increased numerically. Increase in PVF from baseline was significant at all time points except 4-months. Discussion: This study demonstrates a clinically meaningful benefit of a multimodal treatment regimen over a 4-month period for young dogs (<4 years old) with OA-pain. Future work should determine if early, effective treatment is of long-term benefit. [ABSTRACT FROM AUTHOR]

Background Objectives Animals Methods Results Conclusions and Clinical Importance Lesions causing refractory epilepsy, often associated with temporal lobe epilepsy (TLE), can be undetectable on standard magnetic resonance imaging (MRI) in dogs. Automated brain volumetry, widely used in human medicine, can now be applied in veterinary medicine because of the availability of brain atlases.This study aimed to develop an automatic volumetry method, translate the outcomes into the assessment of temporal lobe volumes in dogs with idiopathic epilepsy, and correlate the results with the electroencephalography (EEG) data of epileptiform discharges (EDs).Thirty‐one dogs of various breeds with dominant temporal lobe discharge.Retrospective, observational study. The MRI and EEG examination results of dogs referred for neurological diagnosis data between 2016 and 2021 were retrospectively analyzed. An automated volumetry method was developed, which allowed the evaluation of temporal lobe volumes of the dogs. The asymmetric ratio (AR) was then estimated, and the results were correlated with the EEG EDs.12/31 (38%; 95% CI: 21.8%‐57.8%) dogs had an asymmetric ratio >6%. Among them, reduction in temporal lobe volumes correlated with the side of the EEG EDs in 7 cases. There was no statistical correlation between temporal lobe volume changes and ED location.Preliminary volumetric analysis of the temporal lobes indicates the presence of volume differences between the lobes in some dogs with idiopathic epilepsy. Diagnosis of TLE in dogs based on MRI volumetry in correlation with EEG examination, especially for dogs with drug‐resistant epilepsy, can influence the development of new therapeutic options, such as surgery. [ABSTRACT FROM AUTHOR]

Computed tomography angiography (CTA) was performed under general anaesthesia on a 7‐month‐old toy poodle that was referred with the chief complaints of salivation and neurological symptoms. The CTA revealed a rare form of posthepatic portosystemic shunt (PSS) via the suspected persistent left umbilical vein communicating with the internal thoracic vein in addition to an azygos continuation of the caudal vena cava (CVC). The patient underwent surgery for partial ligation of PSS on Day 4 after the initial examination. On Day 71, after the initial examination, a second surgery was performed for complete ligation. Approximately 10 years have passed since the patient's second surgery, and he is still healthy, and generally in good condition. Although the morphology of the shunt in this case was unusual and was accompanied by an azygos continuation of the CVC, a favourable course of treatment was obtained by ligating the shunt vessel. This case report suggests that CTA can reveal the complex morphological characteristics like our case. Surgical treatment in this case resulted in favourable progress, similar to that in dogs with commonly observed extrahepatic PSS. [ABSTRACT FROM AUTHOR]

Therapies based on mesenchymal stromal cells (MSCs) have become one of the most significant advancements in veterinary regenerative medicine. The isolation of MSCs is usually performed by enzymatic digestion and requires variable times for cell expansion. In addition, these procedures need to be performed in specialized laboratory facilities. An alternative approach to in vitro-expanded MSC therapy is the use of microfragmented adipose tissue (microfat), which is a rich source of cells and growth factors from the stromal vascular fraction. Recent clinical studies support its safety and efficacy in the treatment of musculoskeletal disorders and wound healing. The aim of the present work was to characterize the microfragmented adipose tissue obtained by a new mechanical device, which provides sterile tissue that is ready for use in the clinic by the veterinarian, avoiding the need for specialized laboratory facilities. Microfat-derived MSCs were compared with enzymatically isolated MSCs in terms of their phenotypic characterization, growth rate and differentiation potential. Conditioned medium derived from microfat culture was evaluated for its ability to promote MSC vitality. No differences were observed between MSCs obtained through mechanical fragmentation and those derived from collagenase digestion of adipose tissue, suggesting that the device could serve as a practical source of microfragmented adipose tissue for use in veterinary clinics. [ABSTRACT FROM AUTHOR]

Introduction: Dogs are among the most commonly allergenic pets for children. Data on risk factors for the development of dog allergy are scarce. This study aimed to evaluate the characteristics of children with dog allergy and identify predictors of symptom development with dog exposure. Methods: The study included children with dog allergen sensitization demonstrated by skin prick test (SPT) between September 1, 2019, and December 1, 2022. Demographic, clinical, and laboratory data were collected from the patients' records and interviews with parents. Results: Dog allergen sensitization was detected by SPT in 548 (5.5%) of 9,907 patients. Of these, 507 patients had complete data and were included in the analysis. The patients' median age was 11 (IQR: 8–15) years, 55.8% were male, 97.6% exhibited polysensitization (pollen 75.1%, cat 69.6%), 83.6% had allergic rhinitis, and 46.2% had asthma. Acute dog exposure caused symptoms in 164 patients (32.3%), most commonly sneezing (n = 97) and nasal symptoms (n = 80). Predictors of acute symptoms in dog-sensitized children were male sex (OR: 0.584 [CI: 0.38–0.87]), dog exposure before 1 year of age (OR: 2.35 [CI: 1.18–4.66]), close contact with a dog owner (OR: 2.93 [CI: 1.78–4.8]), and cat allergy (OR: 2.75 [CI: 1.82–4.1]). Conclusion: Approximately one-third of children with dog sensitization developed symptoms after exposure to the dog. Male sex, direct dog exposure before the age of one, close contact with a dog owner, and cat allergy were identified as predictors of dog allergy. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To explain the relationship between cartilage erosion and medial patellar luxation (MPL) and to identify risk factors in dogs. METHODS: A retrospective review was conducted on 90 dogs (103 stifles) surgically treated for MPL between January 2006 and March 2024. Data collected included signalment, side of operated stifle, patellar luxation grade, symptom duration, and lameness score. Cartilage erosion was evaluated for extent and location on the patella and femoral trochlea. Statistical analyses were conducted to identify risk factors. RESULTS: The prevalence of cartilage erosion of the patella and femoral trochlea was 47.6% (49/103) and 54.4% (56/103), respectively, increasing with a higher grade of patellar luxation. Lesions were most prevalent in the distolateral patella and proximomedial trochlea, with generalized lesions more prevalent in grade IV. The extent of both lesions was significantly associated with age, patellar luxation grade, and symptom duration, while body weight significantly correlated only with the cartilage erosion of the patella. No significant correlation was observed with sex, side of operated stifle, or lameness score. CONCLUSIONS: Many patients with MPL exhibited cartilage erosion in the patellofemoral joint, likely due to biomechanical mechanisms. Surgery can be indicated for patients with MPL, as it may prevent cartilage erosion while improving patellofemoral alignment and gait. When selecting surgical candidates, it is important to consider risk factors, such as patellar luxation grade, body weight, age, and symptom duration. CLINICAL RELEVANCE: Early surgical treatment is recommended, especially for dogs with higher body weight and higher grade of MPL, to prevent cartilage erosion and secondary osteoarthritis. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To investigate whether a humeral intracondylar fissure (HIF) alters bone strain in the French Bulldog humerus, we developed a quantitative CT-based 3-D finite element (FE) model for virtual mechanical testing. We hypothesized that higher strains would be seen in the intracondylar region and lateral epicondylar crest if there was a HIF. METHODS: Patient CT scans from 3 (n = 3) French Bulldogs were selected. Dog 1 had a closed distal physis and no HIF. Dog 2 had an open distal humeral physis but no HIF. Dog 3 had an open distal physis and a HIF. A 3-D FE model was built for FE analysis, and pressure was applied to the humerus over the region that contacts the radial head. RESULTS: The maximum principal bone strain patterns differed in each of the models. A path of strain concentration mimicking the typical pattern of a lateral condylar fracture was only found in dog 3. Maximum principal strain exceeded 1% in parts of the lateral epicondylar crest in all 3 dogs. CONCLUSIONS: We developed a patient-specific, quantitative CT-based 3-D FE model for virtual mechanical testing. We accepted our hypothesis. Strain concentration occurred in the intracondylar region and along the lateral epicondylar crest only when a HIF was present. CLINICAL RELEVANCE: The presence of a HIF in French Bulldogs elevates maximum principal bone strain in this region and alters its path in an FE model, which suggests an increased risk of a lateral humeral condylar fracture. [ABSTRACT FROM AUTHOR]

To describe the use of total intravenous anaesthesia (TIVA) in dogs and cats by veterinary anaesthesiologists. A cross-sectional online, voluntary, anonymous survey. Data from 153 answered questionnaires. An anonymous questionnaire was sent via e-mail to diplomates, residents and residency-trained individuals from the American and European Colleges of Veterinary An(a)esthesia and Analgesia, to gather information on the use, perceived advantages, reasons for the use or not of TIVA and attitudes towards this technique in dogs and cats. Descriptive statistics and logistic regression analysis to detect significant associations were performed. The effect size was estimated using the odds ratio (OR) and 95% confidence interval (CI). A significance level of p < 0.05 was used. We obtained 153/703 responses (66% diplomates, 34% residents; overall response rate of 21.7%). Although 99% and 94% of respondents used TIVA in dogs and cats, respectively, only 14% used it frequently (several times a week) in dogs, and < 1% in cats. Most respondents used propofol (97%, dogs) and alfaxalone (85%, cats), mostly combined with opioids. Reasons for not using TIVA more frequently included prolonged recovery (49%, dogs; 61%, cats), higher cost (46%, dogs) and concerns about drug accumulation (44%, cats). Frequent TIVA use was driven by clinical indications (100%) and greater haemodynamic stability (87%). A higher proportion of respondents using TIVA frequently reported the high stability of the anaesthetic plane (20%; OR = 5.0; 95% CI: 1.4–17.8; p = 0.013) and disagreed with using TIVA only when a specific clinical indication existed (OR = 3.3; 95% CI: 1.4–10.0; p = 0.013). Although occasional, TIVA use is reported among veterinary anaesthesiologists. Clinical indications for TIVA are the most likely reason for its use, whereas factors such as a prolonged recovery or higher cost might limit its use. [ABSTRACT FROM AUTHOR]

This case study describes the diagnosis and treatment of a deciduous left maxillary canine tooth root that had been displaced into the pulp of the developing permanent left maxillary canine tooth in a 23-month-old female neutered Cavalier King Charles Spaniel. The patient was initially presented for bilateral persistent deciduous maxillary canine teeth extraction. Seventeen months later the permanent left maxillary canine tooth was found to be non-vital and tooth development had ceased prior to apical closure. Radiographs revealed a radio-opaque dentine-like structure and straight line centrally within the pulp of the permanent tooth. The displacement of the deciduous tooth into the developing permanent tooth was confirmed. This unusual potential complication should be considered when performing deciduous teeth extraction. [ABSTRACT FROM AUTHOR]

A 6-month-old intact male Dalmatian mix puppy was presented for the evaluation of left maxillary swelling due to a suspected cyst and an unerupted left maxillary canine tooth. Removal of the unerupted left maxillary canine tooth (204) and enucleation of the cyst was performed, followed by histological analysis, which identified the maxillary swelling to be a cystic ameloblastic fibroma. Ameloblastic fibromas are rare in companion animals, and to the best of the authors' knowledge, this is the first cystic variant reported in dogs. The clinical, radiographic, cone beam computed tomography, and histological findings of this case are discussed and compared with the findings of previously documented human and domestic animal cases. [ABSTRACT FROM AUTHOR]

Copyright of Summa, Animali da Compagnia is the property of Point Veterinaire Italie s.r.l. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Summa, Animali da Compagnia is the property of Point Veterinaire Italie s.r.l. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Summa, Animali da Compagnia is the property of Point Veterinaire Italie s.r.l. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Summa, Animali da Compagnia is the property of Point Veterinaire Italie s.r.l. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

After correctly diagnosing overweight and obesity in a dog, it becomes important to include proper dietary management. It is necessary to consider the correct proportions between individual nutrients, the selection of their sources, the choice of a feeding model, and supporting weight loss through proper supplementation [ABSTRACT FROM AUTHOR]

Tympanokeratomas (cholesteatomas) are destructive keratinic masses of the middle ear that are often treated surgically. In humans, nonechoplanar (non‐EP) diffusion‐weighted (DW) MRI is efficient in diagnosing tympanokeratomas and differentiating recurrent tympanokeratomas from granulation or fibrous tissue after surgery. The objectives of this study were to (1) determine the characteristics of non‐EP DWI of histologically or cytologically confirmed canine tympanokeratomas, (2) determine the performance of non‐EP DW images, apparent diffusion coefficient (ADC) map and ADC values in discriminating between tympanokeratomas and other causes of otitis media in dogs, and (3) find an optimal ADC cut‐off value. Medical records of dogs diagnosed on MRI with otitis media in two veterinary hospitals were retrospectively reviewed. Sixty‐two ears with a cytological or pathological diagnosis of either tympanokeratoma (36/62) or nontympanokeratoma otitis media (26/62) were selected. Diffusion‐weighted images had an accuracy of 77.4%, a sensitivity of 94.4%, and a specificity of 53.8% for the detection of tympanokeratoma. The ADC value of middle ear content ranged from 517 to 1355.10−6 mm2/s in tympanokeratoma and from 454 to 2447 × 10−6 mm2/s in nontympanokeratoma otitis media. An ADC value below 916 × 10−6 mm2/s interpreted as a tympanokeratoma yielded an accuracy of 78.7%, a sensitivity of 92.6%, and a specificity of 60%. In the study population, combined qualitative analysis of DW images and ADC maps was the most effective method for diagnosing tympanokeratomas with an accuracy of 80.9%, a sensitivity of 92.6%, and a specificity of 65%. [ABSTRACT FROM AUTHOR]

Cross‐sectional imaging is widely used to characterize adrenal gland tumors in humans. In small animal veterinary medicine, while some studies have attempted to distinguish between types of adrenal gland neoplasia using CT, peer‐reviewed studies investigating canine adrenal glands on MRI are scant. This prospective, pilot, single‐center, method comparison, cadaveric study aimed to assess the agreement between ex vivo MRI findings and analogous histopathological findings of the adrenal glands in dogs. The adrenal glands of randomly selected dogs presented for necropsy were examined by MRI (n = 31). Additionally, five adrenal masses in dogs who underwent invasive adrenalectomy (including three adrenocortical carcinomas, one pheochromocytoma, and one adenoma) were imaged. Subsequently, gross pathology and histopathology of all the specimens were performed and correlated with the imaging findings. Adrenal gland lesions were identified on MRI with a sensitivity of 24%, a specificity of 100%, a positive predictive value of 100%, a negative predictive value of 31%, and an accuracy of 45%. The present study provides MRI features of multiple adrenal gland lesions that had never been described in dogs, including cortical hyperplasia, nodular fibrosis, hemorrhage, or multiple tumors, such as adenoma, carcinoma, and hemangiosarcoma. While MRI identified numerous adrenal gland lesions, a significant portion of those went undetected. Therefore, the absence of adrenal gland lesions on MRI does not exclude the possibility of histological lesions being present. [ABSTRACT FROM AUTHOR]

Histologic diagnosis of less well-differentiated cases of canine extramedullary plasmacytomas (CEMPs) may require immunohistochemical confirmation to discriminate these tumors from other round cells tumors including lymphoma, cutaneous histiocytoma, and amelanotic melanomas. CEMPs are characterized by widespread immunoreactivity for multiple myeloma 1 (MUM1) antigen and λ light chains, while the melanocytic marker melan-A has been reported to yield negative results. Here, 33 randomly selected CEMPs, 20 melanocytomas, and 20 malignant melanomas were immunohistochemically tested for MUM1, melan-A, and PNL2. In addition, CEMPs were examined for PAX5, E-cadherin, CD3, CD18, CD20, S100, as well as λ and κ light chain immunoreactivity. All CEMPs were characterized by labeling for MUM1 and λ light chain, as well as variable immunopositivity for the remaining antibodies. Notably, 13 cases of CEMPs (39.4%) exhibited immunolabeling for melan-A. Melanocytic tumors immunolabeled for melan-A (40/40; 100%) and PNL2 (34/40; 85%). An unexpected cytoplasmic immunoreactivity for MUM1 was observed in 2 melanocytic tumors. Summarized, MUM1 or melan-A immunomarkers alone are not sufficient to differentiate between CEMPs and amelanotic melanomas and should be part of a larger immunopanel including λ light chain, CD20, and PNL2. [ABSTRACT FROM AUTHOR]

Cutaneous and subcutaneous mast cell tumors (MCTs) are common canine neoplasms characterized by variable biological behavior. Tumor-associated macrophages (TAMs) and tumor-infiltrating lymphocytes (TILs) can be effective prognostic markers in numerous human neoplasms and are increasingly investigated in dogs. The aim of this study was to characterize immune cells in canine MCTs and their relationship with histological location (cutaneous, subcutaneous) and histologic nodal metastatic status (HN0-3). Thirty-eight MCTs (26 cutaneous, 12 subcutaneous) from 33 dogs with known sentinel lymph node (SLN) metastatic status were immunolabeled for Iba1 (macrophages), CD20 (B cells), CD3 (T cells), and Foxp3 (regulatory T cells). Semiquantitative scoring of interstitial and perivascular CD3+, CD20+, and Foxp3+ cells and morphological evaluation of Iba1+ cells were performed. For each marker, the percent immunopositive area was evaluated by image analysis. All MCTs were diffusely infiltrated by Iba1+ cells and variably infiltrated by CD20+, CD3+, and rare Foxp3+ cells. Stellate/spindle Iba1+ cells were associated with HN2 and HN3 SLNs. Perivascular Foxp3+ cells, CD3+ cells, and percent CD3+ areas were increased in subcutaneous MCTs. Interstitial CD3+ cells were increased in cutaneous MCTs with HN0 SLNs. No differences in CD20+ cells were identified between cutaneous and subcutaneous MCTs and among SLN classes. MCTs were markedly infiltrated by TAMs and variably infiltrated by TILs. Stellate/spindle morphology of TAMs associated with HN2 and HN3 SLNs is suggestive of a pro-tumoral (M2) phenotype. Cutaneous and subcutaneous MCTs have different tumor-immune microenvironments, and T-cell infiltration might contribute to prevention of nodal metastatic spread of cutaneous MCTs. [ABSTRACT FROM AUTHOR]

Histologic grading of canine cutaneous mast cell tumors (cMCTs) has prognostic and therapeutic implications, yet validation for subcutaneous MCTs (scMCTs) is lacking. For scMCTs with or without dermal invasion, determining their biological behavior remains poorly standardized and sometimes sparks controversy. This prospective study aimed to assess the prognostic utility of the 2-tier histologic grading system in MCTs with different growth models (GMs) and explore the prognostic impact of the GM itself. We assessed 6 histologic GM categories: solely cMCT (C-SC0), cMCT with superficial (C-SC1) or deep subcutaneous (C-SC2) involvement, solely scMCT (SC-C0), and scMCT with deep (SC-C1) or superficial (SC-C2) infiltration of the dermis. Ninety-one MCTs from 76 dogs undergoing excision and regional/sentinel lymphadenectomy were examined. GM classification identified 11 (12%) C-SC0 tumors, 12 (13%) C-SC1, 15 (16%) C-SC2, 21 (23%) SC-C0, 15 (16%) SC-C1, and 17 (19%) SC-C2. Mitotic count, 2-tier grade, nodal involvement, surgical margins, and outcome were stratified according to GM. scMCTs lacking dermal invasion, historically associated with a benign clinical course, had a poor prognosis in 10% of cases. cMCTs exhibiting deep subcutaneous involvement included the largest percentage of high-grade tumors (33%), had the highest occurrence of overt nodal metastases (33%), and had the lowest 1-year survival rate (86%). Histologic grade was confirmed as a relevant prognostic factor, surpassing nodal involvement and histologic margin status. The 2-tier histologic grading enabled the identification of all MCTs with aggressive biological behavior, regardless of their cutaneous or subcutaneous location. [ABSTRACT FROM AUTHOR]