IMPORTANCE:The Veterinary Neurologic Disease Library has been created as an educational resource library for veterinary professionals related to breed-associated neurologic diseases in dogs. OBJECTIVE:To develop an open-access library that serves as a curated collection repository of peer-reviewed literature pertaining to dog breeds and neurologic diseases. METHODS:Dog breeds were identified using the American and United Kennel Club registered breed lists. Disease terms were collected from published texts discussing veterinary neurologic diseases. Publicly available resources were searched by inputting keywords, including dog breeds, specific neurologic diseases, clinical signs, and additional related terms. Retrieved information was stored in a Zotero web-library, and automated searches continue to be conducted monthly. Original peer-reviewed manuscripts (in English) were categorized for inclusion with an individual unique breed was identified with a neurologic disease. RESULTS:The library is currently active and accessible online. Four hundred breeds have been included for peer-reviewed citations of neurologic diseases. At the time of this writing, over 1,900 scholarly citations have been identified and categorized. CONCLUSIONS AND RELEVANCE:This centralized, open-access, repository of breed-associated neurologic diseases can be accessed to search breed and neurologic disease to assist primary care clinicians in the identification breed-associated neurologic disease in dogs and locating original source publications.
IMPORTANCE:Kilovoltage (kV) X-ray radiotherapy systems have been introduced as a potential treatment option for companion animal radiotherapy, particularly for superficial targets. On the other hand, the lack of experimental validation of dose delivery accuracy has limited their broader clinical adoption. OBJECTIVE:A measurement-based dosimetric comparison was made between kV and megavoltage (MV) X-ray systems. METHODS:A 300 kV X-ray radiotherapy system and a 6 MV linear accelerator were evaluated for percent depth dose, penetration depth, beam profiles, and field size output factors. Eight static-field plans were generated for targets at varying depths and tissue densities in an anthropomorphic head phantom. Point doses were measured with thermoluminescent dosimeters and compared with treatment planning system-calculated doses. The calculated-to-measured absolute percentage differences were compared between the kV and MV systems using the Wilcoxon signed-rank test with a bootstrap 95% confidence interval. RESULTS:Compared with the MV beam, the kV X-ray beam exhibited a negligible buildup distance, higher field-size dependence, a pronounced heel effect, and substantially lower penetration depth. Despite these dissimilarities, the absolute differences between the calculated and measured point doses were 0.1%-4.0% and 3.1%-6.5% for the kV and MV systems, respectively, across different target depths and tissue densities. The differences were significantly smaller for kV (median paired difference, -1.9 percentage points; 95% CI, -3.8 to -0.7; p = .0078). CONCLUSIONS AND RELEVANCE:Under the evaluated static-field phantom conditions, the commissioned kV treatment-planning model showed calculated-to-measured differences of 0.1%-4.0%. Although these values were lower than those for MV, this finding does not establish higher dosimetric accuracy for the kV system because measurement-related uncertainties may have contributed.
IMPORTANCE:Differentiating between dystrophic and metastatic soft tissue calcifications in dogs is clinically essential but remains diagnostically challenging. OBJECTIVE:This retrospective study aimed to categorize canine soft tissue calcifications on whole-body computed tomography (CT) based on anatomical location and pattern, determine if CT can differentiate between metastatic and dystrophic types based on these factors, and identify pattern tendencies within dystrophic subtypes. METHODS:Calcifications were classified into group 1 (dystrophic) and group 2 (metastatic). Multivariable generalized estimating equation (GEE) logistic regression identified variables independently associated with metastatic calcification. Group 1 was subdivided into 1a (with mass) and 1b (without mass) to assess pattern tendencies across organs. RESULTS:Organ location alone was not independently associated with calcification type. Instead, similar organ-specific patterns were observed across etiologic groups, indicating substantial topographic overlap; both groups 1b and 2 predominantly exhibited round/oval multifocal patterns in kidneys, and curvilinear/rim diffuse patterns in the vasculature. Conversely, group 1a showed a higher propensity for amorphous/irregular patterns within masses. In multivariable GEE analysis, focal distribution was significantly associated with metastatic calcification (adjusted odds ratio [OR], 1.18; 95% confidence interval [CI], 1.02-1.37; p = 0.029) compared to multifocal distribution, while curvilinear/rim shapes showed a curvilinear/rim shape was not significantly associated with metastatic calcification after adjustment (OR, 1.26; 95% CI, 0.98-1.63; p = 0.072) compared to round/oval shapes. CONCLUSIONS AND RELEVANCE:Whole-body CT effectively categorizes the locations and patterns of canine soft tissue calcifications and identifies distinct tendencies within dystrophic subtypes. However, due to significant organ-specific topographic overlaps, CT imaging alone is insufficient to definitively differentiate metastatic from dystrophic calcifications, necessitating comprehensive clinical and biochemical correlation.
IMPORTANCE:Understanding the molecular mechanisms driving H5N1 clade 2.3.4.4b is critical for pandemic preparedness. OBJECTIVE:To characterize the molecular drivers of viral fitness and mammalian adaptability in recent H5N1 viruses by integrating evolutionary dynamics with structural simulations. METHODS:This study analyzed 2,398 H5Nx genomes (2000-2024) through phylogenetic and selective pressure analyses. HA/NA structures were predicted with AlphaFold 3 and evaluated by AutoDock4 docking, whereas polymerase-ANP32A/B complexes were modeled using template-based methods and their binding free energies were estimated using MM/GBSA. Polymerase-ANP32E complexes were predicted with AlphaFold 3 and similarly evaluated by MM/GBSA. The binding affinities (ΔG) for the sialic acid (SA) receptors and human ANP32 proteins were quantified through molecular mechanics/generalized born surface area calculations. RESULTS:Clade 2.3.4.4b showed significant antigenic drift in the HA receptor binding site, reducing affinity for α2,3-SA and α2,6-SA receptors. On the other hand, the emergence of a full-length stalk N1 NA with second sialic acid-binding site mutations (e.g., N366S) compensated for reduced HA affinity by enhancing the NA binding stability. In the polymerase complex, both the PB2-627E/631L variant (-144.00 kcal/mol; unadjusted p = 0.0058) and the known mammalian-adaptive 627K/631M variant (-144.67 kcal/mol; unadjusted p = 0.0165) showed more favorable predicted human ANP32B binding free energies than the ancestral 627E/631M state (-136.46 kcal/mol). CONCLUSIONS AND RELEVANCE:The co-occurrence of HA, NA, PB1, and PB2 signatures was associated with clade expansion and produced structural predictions consistent with altered receptor or ANP32 interactions; experimental validation is required before inferring effects on fitness or zoonotic risk.
IMPORTANCE:Heartworm disease can lead to chronic cardiopulmonary complications in dogs, and treatment is often prolonged and costly. In Korea, Dirofilaria immitis, the causative agent of canine heartworm disease, has been reported in both dogs and mosquitoes and is generally considered endemic. OBJECTIVE:This field study evaluated the effectiveness and safety of a combination of milbemycin oxime and lotilaner (Credelio Plus) for the prevention of heartworm disease in client-owned dogs in the Republic of Korea. DESIGN/SETTING/PATIENTS:This randomized, single-blind, controlled field trial was conducted between June 2023 and February 2024. Client-owned dogs that were at least 8 weeks old, weighed more than 2.0 kg, were walked more than 3 times per week, and tested negative for heartworm at baseline were enrolled. INTERVENTIONS:The dogs were allocated in a 1:1 ratio to receive either the investigational veterinary product (milbemycin oxime/lotilaner) or the control veterinary product (milbemycin oxime/afoxolaner) for six consecutive monthly treatments (days 0, 30, 60, 90, 120, and 150). MAIN OUTCOMES AND MEASURES:Prevention of D. immitis infection was assessed monthly from days 0 to 180 using a commercial antigen test kit and conventional polymerase chain reaction. Safety was evaluated using body weight, physical examination findings, hematology and serum chemistry analyses, and adverse event monitoring to assess general health status and identify potential treatment-related abnormalities during the study period. RESULTS:A total of 53 dogs were enrolled in the study, of which 52 were included in effectiveness and safety analyses. All dogs remained negative for D. immitis during the study period. In the safety evaluation, no statistically significant changes were observed in body weight, physical examination findings, or hematology and serum chemistry analyses following milbemycin oxime/lotilaner administration (p > 0.05). No adverse events were observed. CONCLUSIONS AND RELEVANCE:The results of this study support the use of milbemycin oxime/lotilaner combination as a safe and effective option for the prevention of canine heartworm infections under field conditions in Korea. These findings indicate that this combination product may be a useful option in veterinary parasite control. TRIAL REGISTRATION:Animal and Plant Quarantine Agency, Korea (clinical trial number: A221512).
IMPORTANCE:Natural killer (NK) cells are critical effectors of innate immune surveillance and can eliminate malignant cells without prior sensitization. Given the biological and genetic parallels between canine and human cancers, NK cell-based immunotherapies have strong translational potential in veterinary oncology. However, the lack of an efficient and reproducible ex vivo expansion protocol for canine NK cells remains a major barrier to clinical application. Establishing culture conditions for expansion of functional canine NK cells would support adoptive NK cell therapy and translational research. OBJECTIVE:This study aimed to evaluate the effectiveness of genetically modified feeder cells and optimized culture media in expanding canine NK cells. METHODS:Canine peripheral blood mononuclear cells were co-cultured with irradiated genetically modified K562 or ARH77 cells in either RPMI-1640 or Dulbecco's Modified Eagle Medium (DMEM)/F12-based media. NK cell expansion, purity, cytotoxicity and expression of NK cell-associated receptors were evaluated using flow cytometry, cytotoxicity assays, and quantitative reverse transcription polymerase chain reaction. RESULTS:The combination of DMEM/F12-based medium and genetically modified ARH77 feeder cells yielded the highest NK cell expansion rate and purity among the tested conditions. Cytotoxicity differed significantly according to medium type, whereas no significant difference was observed between feeder cell types. In addition, the NK cell-associated receptors were significantly upregulated in expanded NK cells. CONCLUSIONS AND RELEVANCE:Genetically modified ARH77 feeder cells with DMEM/F12-based culture media demonstrated superior efficiency in promoting the ex vivo expansion of canine NK cells, achieving high purity and enhanced cytotoxic potential. These findings highlight a promising and reproducible platform for generating functional NK cells, offering a practical and scalable strategy to support the development of NK cell-based veterinary immunotherapy.
IMPORTANCE:Accurate assessment of osteoarthritis-related pain in dogs requires validated, language-specific clinical metrology instruments. The absence of a Korean version of the widely used Canine Brief Pain Inventory (CBPI) limits standardized pain assessment and outcome evaluation in Korean-speaking clinical and research settings. OBJECTIVE:This study aimed to develop and perform an initial psychometric evaluation of the Korean version of the CBPI. METHODS:This observational cross-sectional study included 56 dogs with osteoarthritis and 22 healthy controls. Construct validity was assessed using exploratory and confirmatory factor analyses. Convergent validity was assessed using Spearman correlations between CBPI scores and the owner-reported quality-of-life item. Discriminant validity was evaluated through group comparisons between dogs with osteoarthritis and healthy controls. Internal consistency was evaluated using Cronbach's α. RESULTS:Exploratory analysis identified a dominant general pain factor (eigenvalue = 8.04; 80.4% variance). Confirmatory factor analysis demonstrated superior relative fit for the two-factor model (χ²/df = 2.94, comparative fit index [CFI] = 0.917, root mean square error of approximation [RMSEA] = 0.186, standardized root mean square residual = 0.044) compared with the one-factor model (χ²/df = 4.13, CFI = 0.861, RMSEA = 0.236). CBPI scores showed significant negative correlations with quality of life in dogs with osteoarthritis (ρ = -0.516 to -0.485; corresponding 95% confidence intervals ranged from -0.710 to -0.248; p < 0.001). Dogs with osteoarthritis had higher CBPI total scores than healthy controls (median, 18.0 vs. 0; p < 0.001). Cronbach's α coefficients ranged from 0.951 to 0.968. CONCLUSIONS AND RELEVANCE:The Korean CBPI demonstrated excellent internal consistency and preliminary evidence of construct validity for assessing osteoarthritis-related pain in dogs, supporting its use as an owner-reported outcome measure in Korean-speaking clinical and research settings. Future longitudinal studies should evaluate its test-retest reliability and responsiveness to treatment.
IMPORTANCE:Tumor protein p53 (TP53) alterations are frequently reported in canine cancers but remain incompletely characterized due to differences in reference genomes and sequencing cost. OBJECTIVE:To evaluate a cost-efficient primer-walking approach for TP53 variant screening in dogs with spontaneous tumors. METHODS:Tumor tissue (n = 10) or blood (n = 16) was collected from 26 dogs with suspected neoplasia. Interpretable TP53 sequences spanning introns and exons 2-11, excluding long intron 1 and non-protein-coding exon 1, were obtained by primer-walking polymerase chain reaction and Sanger sequencing. Bidirectional reads were compared with the Ensembl ROS_Cfam_1.0 v114 reference sequence. RESULTS:TP53 gene sequence variations were observed in 18/26 sequenced tumor cases, including one exonic frameshift insertion and 17 noncoding variants: 13 intronic variants and 4 variants in the 5' untranslated region. Recurrent substitutions and deletions occurred in the intron 8-10 region. Variants were detected in lymphomas and carcinomas, including cases from several small breeds, but no significant association with tumor type or breed was demonstrated. CONCLUSIONS AND RELEVANCE:Primer-walking Sanger sequencing can screen TP53 regions beyond coding exons in canine tumor samples. Matched tumor-normal sequencing is needed to determine somatic versus germline origin and to evaluate noncoding TP53 variants as potential biomarkers or drivers.
IMPORTANCE:Despite ongoing intercontinental spread of clade 2.3.4.4b H5N1 highly pathogenic avian influenza (HPAI), surveillance data from Mongolia -- a critical junction between Central and East Asian migratory flyways -- remain scarce, leaving a gap in understanding how viruses move between northern breeding areas and southern wintering grounds. OBJECTIVE:We aimed to detect and genetically characterize HPAI viruses in wild bird populations in Mongolia and assess their relationship with viruses circulating in East Asia. METHODS:Active surveillance was conducted at Ganga Lake, Mongolia, in October 2024. A total of 352 wild bird fecal samples were collected and tested for AIVs. Viral isolates were subtyped, whole-genome sequenced, and phylogenetically analyzed. Host species was identified using c oxidase I barcoding. RESULTS:Sixteen AIVs were isolated, including one clade 2.3.4.4b H5N1 HPAI virus (M9-3) from whooper swan feces. Genomic analysis revealed M9-3 had > 99% similarity with Korean and Japanese H5N1 isolates reported in late 2024 and undergone recent reassortment and disseminated through migratory flyways. CONCLUSIONS AND RELEVANCE:This is the first detection of clade 2.3.4.4b H5N1 in Eastern Mongolia in a fecal sample during late autumn. These findings underscore Mongolia's importance as a sentinel location for interregional HPAI dissemination.
IMPORTANCE:Edwardsiella tarda induces severe systemic infections in olive flounder (Paralichthys olivaceus), requiring long-acting parenteral therapies to ensure optimal antimicrobial exposure. While amoxicillin trihydrate (AMXT) and florfenicol (FFC) are effective monotherapies, the pharmacokinetic-pharmacodynamic (PK-PD) rationale for their combined intramuscular administration remains insufficiently characterized. OBJECTIVE:To evaluate the PK-PD profile, synergistic activity, and therapeutic efficacy of a fixed-dose intramuscular AMXT-FFC combination against E. tarda in olive flounder. METHODS:Minimum inhibitory concentration (MIC) and time-kill assays were conducted. Olive flounder were administered amoxicillin (AMX, 10 mg/kg), FFC (10 mg/kg), or their combination (10 + 10 mg/kg) via intramuscular injection. PK parameters were estimated using noncompartmental analysis. PK-PD indices, including %time above MIC (%T > MIC) and area under the concentration-time curve (AUC)/MIC, were calculated based on the combined MIC (0.5 µg/mL). Therapeutic efficacy was assessed using an dose causing 70% mortality challenge model (3.7 × 10⁶ colony-forming units [CFU]/fish). RESULTS:The AMXT-FFC combination exhibited synergism (ΣFIC = 0.625), achieving a ≥ 3 log₁₀ CFU/mL reduction within 24 h. Co-administration significantly elevated Cmax and prolonged t1/2, reaching 34.12 µg/mL and 33.27 h for AMX, and 31.59 µg/mL and 13.94 h for FFC, respectively. PK-PD integration showed that PK-PD indices met prespecified efficacy targets (AMX: 100% T > MIC; FFC: AUC/MIC = 1,610.82). In vivo, the combination significantly improved survival compared to controls (75% vs. 27.5%; relative percent survival = 65.5%, p < 0.05). CONCLUSIONS AND RELEVANCE:A single intramuscular administration of the AMXT-FFC combination provides synergistic antibacterial activity, prolongs exposure, and achieves prespecified PK-PD targets under the controlled experimental conditions.
IMPORTANCE:Protozoan blood parasites, including Trypanosoma evansi, Theileria annulata, and Babesia spp., remain major constraints to livestock health and productivity across the Middle East and North Africa (MENA). Disease control relies heavily on a limited number of chemotherapeutic agents that have been used for decades, raising concern about declining efficacy and emerging drug resistance. OBSERVATIONS:This review synthesized and critically evaluated field, experimental, and molecular evidence of antiparasitic drug resistance in major protozoan blood parasites of livestock in the MENA region. A narrative review was conducted using major scientific databases to identify peer-reviewed studies published between January 2000 and December 2025. Eligible studies reported treatment outcomes, experimental drug sensitivity, or molecular resistance markers in T. evansi, T. annulata, or Babesia spp. Evidence was organized by parasite species and evidence type; meta-analysis was not performed due to heterogeneity. The most consistent evidence of confirmed drug resistance was found for T. annulata, where buparvaquone treatment failure is repeatedly associated with mutations in the cytochrome-b and TaPIN1 genes across multiple MENA countries. For trypanosomosis, recurrent field failures and experimental resistance to diminazene and isometamidium are reported, but validated molecular markers for T. evansi remain unavailable. In babesiosis, reported outcomes indicate variable or incomplete responses to imidocarb and diminazene, reflecting functional treatment failure rather than confirmed genetic resistance. CONCLUSIONS AND RELEVANCE:A clear mismatch exists between widespread field observations and limited molecular confirmation. Strengthened surveillance, standardized efficacy trials, rational drug use, and integrated parasite-control strategies are urgently needed in the MENA region.
IMPORTANCE:Case-based learning (CBL) represents a promising shift toward competency-based veterinary education, but the evidence from Southeast Asian programs is limited. OBJECTIVE:This study evaluated veterinary students' perceptions of structured CBL effectiveness in Thai veterinary education and whether these perceptions varied with academic performance. METHODS:A convergent parallel mixed-methods design was used at the Faculty of Veterinary Medicine, Kasetsart University. Quantitative data were collected from 318 students (88.3% response rate) using a structured 22-item questionnaire across four domains (professional knowledge, communication skills, personal benefits, facilitator performance) on 5-point Likert scales. Groups were compared by Grade Point Average (GPA; 2.01-2.99 vs. > 2.99) using the Mann-Whitney U test. Nine focus groups (n = 63) were analyzed thematically. RESULTS:Students perceived all four domains positively. Mean scores were comparable for professional knowledge (4.08 ± 0.61), facilitator performance (4.06 ± 0.72), and personal benefits (4.03 ± 0.65), and lowest for communication skills (3.89 ± 0.75). Students with a GPA of 2.01-2.99 reported greater perceived benefit than higher-achieving peers in professional knowledge (U = 10,109; p = 0.036; r = 0.14) and personal benefits (U = 10,167; p = 0.043; r = 0.14); differences in communication (U = 10,734; p = 0.192; r = 0.09) and facilitator performance (U = 10,783; p = 0.213; r = 0.08) were not significant. Thematic analysis produced two themes: perceived CBL effectiveness and areas for development. CONCLUSIONS AND RELEVANCE:Students perceived CBL as offering meaningful educational value, with lower-performing students perceiving particularly strong benefits, and perceived that CBL supported their clinical reasoning, collaborative learning, and communication. Effective implementation was perceived to require systematic faculty development, case-curriculum alignment, and structured group management. These findings support broader CBL integration while highlighting critical implementation considerations for educational equity.
IMPORTANCE:Enterococci are opportunistic uropathogens increasingly associated with recurrent urinary tract infections (UTIs) in companion animals, raising concerns about their virulence potential and high antimicrobial resistance. OBJECTIVE:To characterize the species distribution, virulence-associated genes, and antimicrobial resistance profiles of urinary Enterococcus isolates from dogs and cats with recurrent UTIs, including vancomycin resistance determinants. METHODS:This study analyzed 106 monomicrobial urinary Enterococcus isolates from 61 dogs and 45 cats with recurrent UTIs. Species identification was followed by multiplex polymerase chain reaction for vanA, vanB, vanC1, and vanC2 and for virulence-associated genes (fsr, efm, esp, cylA, cad1, ace, gelE, and asa1). The antimicrobial susceptibility was assessed by disc diffusion. The associations were evaluated using univariate comparisons and multivariable analyses. RESULTS:Among the 106 isolates, 68 (64.2%) were Enterococcus faecalis and 38 (35.8%) Enterococcus faecium. E. faecalis was more frequently isolated from cats than dogs (77.8% vs. 54.1%; odds ratio, 2.97). The virulence profiles differed according to species; E. faecalis was more likely to carry ace, gelE, asa1, cylA, fsr, and esp, and showed a higher overall virulence profile. The prevalence of resistance was high for erythromycin (82.1%), rifampicin (78.3%), tetracyclines (70.8%), and fluoroquinolones (~59%), with multidrug resistance detected in 84.9% of isolates. Nitrofurantoin resistance was more common in E. faecium than E. faecalis (47.4% vs. 5.9%) and was independently associated with E. faecium in multivariable analyses. The vancomycin-resistance gene vanB was detected in 2.83% of isolates. CONCLUSIONS AND RELEVANCE:Recurrent UTIs in dogs and cats were associated with high rates of multidrug-resistant Enterococcus isolates and species-specific virulence and resistance patterns. These findings support the use of species-level identification and susceptibility testing-guided therapy to improve antibiotic stewardship and the clinical outcomes in recurrent UTIs in companion animals.
IMPORTANCE:Bovine alphaherpesvirus 1 (BoAHV-1) is one of the most important viruses that infects cattle and causes significant economic losses. Understanding the critical mechanisms underlying viral pathogenesis is essential for developing novel antiviral strategies. OBJECTIVE:To determine if eukaryotic translation elongation factor-1 Δ (EEF1D) is involved in DNA damage repair in the presence or absence of BoAHV-1 infection by regulating the DNA damage response (DDR) signaling of P53-binding protein 1 (53BP1) and γH2AX. METHODS:Bovine kidney (MDBK) cells were transfected with EEF1D-specific small interfering RNAs (siRNAs) or a scrambled control siRNA, followed by either a mock infection or virus infection. The effects of EEF1D knockdown on the γH2AX protein levels, γH2AX foci formation, and 53BP1 protein expression and foci formation were evaluated by Western blotting and immunofluorescence assays. RESULTS:siRNA-mediated EEF1D depletion increased the γH2AX protein levels irrespective of a viral infection and enhanced γH2AX foci formation in BoAHV-1-infected cells. In mock-infected cells, EEF1D knockdown increased the steady-state 53BP1 protein levels and 53BP1 foci formation. In contrast, during viral productive infection, EEF1D knockdown reduced the 53BP1 protein levels despite concurrently suppressing viral protein expression. CONCLUSIONS AND RELEVANCE:EEF1D appears to alleviate BoAHV-1-induced DNA damage, potentially by modulating 53BP1-related DDR signaling. Hence, EEF1D may be a host factor linking viral replication and DDR regulation and may contribute to BoAHV-1 pathogenesis.
IMPORTANCE:Laryngeal stenosis is a frequent and life-threatening cause of upper airway obstruction in dogs. Current surgical options, although effective, are invasive and associated with high morbidity. Species-specific laryngeal stents may provide a safer alternative. OBJECTIVE:To evaluate the anatomical adaptation and feasibility of a novel custom three-dimensional (3D)-printed laryngeal prosthesis designed for canine laryngeal stenosis in a cadaveric model. METHODS:A prototype stent was produced using 3D printing and assessed in eight canine cadavers of different breeds and skull conformations. Glottic opening was measured at baseline, after endotracheal intubation, and following stent placement using calibrated laryngoscopic imaging. Anatomical fit, displacement, and epiglottic function were evaluated. RESULTS:After stent placement, mean glottic opening was consistently smaller than that achieved with endotracheal tubes (e.g., size L: 17.3 ± 2.26 mm vs. 23.65 ± 6.72 mm), although this difference was not statistically significant, suggesting a more physiologic dilation. Optimal anatomical adaptation was observed in five of eight cases. Mild displacement occurred only in undersized implants, and epiglottic closure was preserved in all specimens. CONCLUSIONS AND RELEVANCE:This preliminary cadaveric study demonstrates that a custom canine-specific 3D laryngeal prosthesis can achieve stable anatomical integration without excessive glottic expansion or interference with epiglottic function. Although cadaveric testing cannot assess inflammatory responses, the limited dilation observed indicates low radial force. These findings support the potential of this device as a species-specific alternative to traditional surgical approaches. In vivo evaluation with medical-grade materials is warranted to confirm safety, tolerability, and long-term efficacy.
IMPORTANCE:Nitric oxide (NO), synthesized from L-arginine by nitric oxide synthases (NOS), acts as a conserved signaling molecule involved in the regulation of food intake across animal taxa. Understanding its function has gained importance in veterinary medicine, animal production, and comparative physiology, especially given species-specific differences in arginine metabolism and immune-nutritional interactions. OBSERVATIONS:This review provides a comparative synthesis of the role of NO in appetite regulation in mammals, birds, and aquatic animals, highlighting conserved mechanisms, species-specific differences, and gaps requiring further investigation. In mammals, NO modulates hypothalamic circuits controlling satiety and hunger in a bidirectional, energy-dependent manner. Birds, lacking endogenous arginine synthesis, show reduced feed intake with elevated NO levels. In fish, NO-especially via agmatine-suppresses feeding by downregulating orexigenic signals and enhancing insulin-mediated pathways. CONCLUSIONS AND RELEVANCE:NO functions as a conserved but flexible regulator of food intake across taxa. Future studies employing molecular, nutritional, and behavioral tools are needed to clarify species-specific mechanisms and optimize NO-targeted feeding strategies in production animals.
IMPORTANCE:The nasal diverticulum (ND), a blind cutaneous pouch extending from the nasal vestibule (NV), is unique to Equidae. Although anatomical and histological descriptions of the ND are available for horses and donkeys, detailed studies in zebras remain limited. OBJECTIVE:To investigate and characterize the anatomical and histological features of the ND in zebras and compare these findings with those observed in other species. METHODS:Silicone casts of the NDs were prepared from two of three female Grant's zebra carcasses for anatomical measurements, followed by dissection for gross morphological examination. Three-dimensional reconstructions generated from computed tomography images of the casts were used to obtain morphological measurements. In addition, paraffin-embedded sections stained with hematoxylin and eosin were prepared for histological evaluation and morphometric analysis. RESULTS:The NDs of zebras were curved blind pouches, slightly compressed mediolaterally, and extended over the nasal process of the incisive bone. Based on the impression of the nasal process, the ND was divided into cranial and caudoventral regions. The nasolacrimal orifice was located on the lateral aspect of the nostril. An undulating fold was observed on the medial wall of the cranial region of the ND. The total volume of the ND was approximately 36 mL. The surface was covered with fine hairs associated with secondary hair follicles. Compared with the NV, the ND exhibited significantly reduced epidermal thickness and fewer sebaceous glands, sweat glands, and secondary hair follicles. CONCLUSIONS AND RELEVANCE:This study provides novel anatomical and histological data on the ND in zebras, highlighting species-specific differences compared with other animals.
IMPORTANCE:The nasal turbinate is a structurally complex organ essential for air conditioning and defense against inhaled toxicants. Despite its importance, standardized histological criteria for Beagle nasal turbinates have not been fully established, limiting the reproducibility and comparability of toxicological and pathological evaluations. OBJECTIVE:To characterize region-specific histological features of the Beagle nasal turbinates using anatomically defined anterior, middle, posterior, and olfactory regions. METHODS:Nasal cavities from five 8-month-old Beagle dogs and five 10-week-old New Zealand White rabbits were sampled at four anatomically defined transverse levels corresponding to the anterior (last upper incisor teeth), middle (upper canine teeth), posterior (third premolar teeth), and olfactory (fourth premolar teeth) regions, using reproducible dental and cranial landmarks. Hematoxylin and eosin and periodic acid-Schiff staining were performed to evaluate epithelial types, submucosal structures, and goblet cell distribution. RESULTS:Gross transverse sections revealed clear anatomical differences between Beagles and rabbits, particularly in turbinate complexity. In the anterior region, Beagles were entirely lined by transitional epithelium, whereas rabbits had a mixed layer of stratified squamous epithelium. In the middle region, Beagles showed a broader distribution of respiratory epithelium with abundant goblet cells. In the posterior and olfactory regions, where olfactory epithelium was mainly distributed, Beagles showed more well-developed and significantly thicker olfactory epithelium compared to rabbits; mean difference 39.889 μm (95% CI, 11.079-68.698), p = 0.0138. CONCLUSIONS AND RELEVANCE:This study is the first to propose standardized, region-specific histological criteria for Beagle nasal turbinates, supported by quantitative analysis. By presenting its unique histological structures and traits, this study provides a reproducible reference framework for Beagle nasal cavity histology.
IMPORTANCE:Endogenous Cushing's syndrome increases the risk of cardiac hypertrophy, dysfunction, and cardiovascular mortality. Given the high prevalence of hyperadrenocorticism (HAC) and myxomatous mitral valve disease (MMVD) in dogs, endocrine-cardiac interactions may influence disease progression but remain poorly characterized. OBJECTIVE:To evaluate the effects of concurrent HAC on cardiac remodeling and function in dogs with subclinical MMVD and identify metabolic and neurohormonal markers, particularly catecholamine metabolites, associated with left ventricular hypertrophy and dysfunction. METHODS:Twenty-one client-owned dogs (HAC + MMVD, MMVD-only controls, and healthy controls [each n = 7]) were prospectively enrolled. Echocardiographic variables, including speckle-tracking echocardiography, hematologic and biochemical parameters, and urinary normetanephrine: creatinine ratios, were evaluated at baseline and follow-up. RESULTS:The HAC + MMVD group showed significantly increased urinary normetanephrine: creatinine ratios than both healthy control group and MMVD-only control group (p = 0.011 and p = 0.007, respectively). Urinary normetanephrine: creatinine ratio was independently associated with interventricular septum wall thickness in diastole (IVSdN, B = 0.000222, 95% confidence interval [CI] 0.000050 to 0.000393, p = 0.026). Δ Urinary normetanephrine: creatinine was positively associated with Δ IVSdN after adjusting for Δ days (B = 0.000308, 95% CI 0.000108 to 0.000507, p = 0.016). Global longitudinal strain (GLS) was lower in the HAC + MMVD group than both the healthy control group and the MMVD-only control group (p = 0.001 and p = 0.002, respectively). However, GLS was not associated with normetanephrine levels (r = 0.179, 95% CI -0.698 to 1.000, p = 0.720). CONCLUSIONS AND RELEVANCE:This exploratory pilot study is the first suggesting a potential neuroendocrine mechanism underlying endocrine-cardiac remodeling in dogs with concurrent HAC and MMVD, whereby increased catecholamine activity may be associated with left ventricular hypertrophy.
