Search Results (26)

Although extensively studied in humans, data on the middle cranial fossa foramina remain limited in dogs, despite their different skull morphology and high relevance to veterinary neurology, surgery and oncology. In this retrospective anatomic study, we aimed to fill this gap by presenting the morphometric data of these foramina in domestic dogs of different breeds, ages, body weights, and skull sizes. The study used CBCT images of 40 dogs. Dogs were divided into three groups (small, medium, and large), regardless of sex, body weight, and breed, using neurocranium length. Then, morphological and morphometric analyses of the foramina were performed. The neurocranium length of each group differed significantly from the others (p < 0.001). In each group, the orbital fissure and round and oval foramina were bilaterally located rostrally to caudally and were of similar size (p > 0.05). While the orbital fissure was a canal in 80% of dogs, in dogs with medium and large skull sizes (17.5%), the spinous foramen showed variation, becoming both a foramen and a canal. The opening sizes increased along with the skull size (p < 0.001); the widest opening was the orbital fissure, and the narrowest opening (except for the spinous foramen) was the oval foramen. The findings may guide skull base surgeries, regional anesthesia, and the diagnosis of cranial nerve dysfunctions. Furthermore, a classification based on neurocranial length is anticipated to provide more objective craniometric measurements in animals with diverse head types and body weights. Full article

Dental malocclusions are common and often underdiagnosed situations in dogs, which might result in oral trauma, impaired mastication, and periodontal disease. Nevertheless, scientific investigations into breed-specific variations in dentition remain scarce. To evaluate breed-specific dental variations in dogs, a retrospective cross-sectional analysis was conducted on 92 clinical canine head computed tomography (CT) scans obtained in Chengdu, China, representing a range of breeds and skull morphologies. Dental alignment and occlusal relationships were calculated using standardized malocclusion classification criteria. As a result, malocclusions were found and identified in 46.7% of dogs. Among them, brachycephalic breeds indicated a high prevalence of malocclusion, with Shiba Inu dogs demonstrating the highest malocclusion rate (66.7%), whereas Golden Retrievers and Akitas showed the lowest prevalence (16.7%). Class I malocclusions characterized by dental crowding were most common (44.19%), followed by Class II malocclusions (overbite) (30.23%), and Class III malocclusions (underbite) (20.93%). Our findings demonstrated a strong association between skull morphology and dental alignment abnormalities. Full article

The growing demand for customized pet diets highlights the shortcomings of commercial dog foods designed for all breeds, especially when it comes to addressing breed-specific diseases, metabolic disorders, and health risks. This research presents the development and evaluation of a hybrid system for formulating wet canine food recipes. The system combines data on ingredients, veterinary feeds, and breed-related diseases; the architecture includes a recommendation module for ingredient selection and a linear programming block for recipe optimization, considering veterinary nutrient restrictions. The evaluation of the system included automatic classification of foods by specialization, visual analysis of recipe clustering, and comparison of formulas obtained by different models. The average precision of label recovery was 85.4% for TF-IDF and 88.2% for the E5 model. A comparison of ingredient extraction methods showed that machine learning produces more stable recipes, while the statistical approach provides greater variability. The developed system demonstrates potential for automating recipe creation, filling in missing data, and developing veterinary decision support platforms aimed at personalized diet selection based on the physiological needs of animals. Full article

Myxomatous mitral valve disease (MMVD) is the most prevalent cardiac disorder in small and toy breed dogs, with the Cavalier King Charles Spaniel (CKCS) showing exceptionally high predisposition and early onset of the disease. MMVD is characterized by progressive mitral valve degeneration, volume overload, and eventual development of congestive heart failure (CHF). Given the strong hereditary component in CKCS, considerable research has focused on elucidating the genetic basis of MMVD in this breed. This review article summarizes the current state of knowledge on the phenotypic features, inheritance, and candidate loci potentially responsible for early onset and severe course of the disease. The pathogenesis of the disease, its classification, and the effects of breeding programs aimed at reducing the occurrence of MMVD have been described. Key findings include associations between MMVD severity and polymorphisms in genes such as NEBL, ACE, CDK6, HEPACAM2, COL5A1, and FAH, as well as evidence implicating dysregulated TGF-β signaling, serotonin signaling, and extracellular matrix remodeling pathways. The current state of knowledge on the role of miRNA in the pathogenesis of MMVD was also summarized. Despite these findings, no specific high-penetrating mutation has been identified. MMVD is a complex, polygenic condition shaped by regulatory variants and breed-specific genetic bottlenecks. Comparative studies underscore the translational relevance of canine MMVD to human mitral valve disease, while genomic insights may be basis for the future selective breeding strategies and therapeutic approaches. Further large-scale, integrative studies combining genomics, transcriptomics, and functional validation are needed to clarify disease mechanisms and support targeted treatment in CKCS as well as the development of new breeding strategies and programs. Full article

This work presents EDICA, a two-stage architecture for fine-grained image classification, which is a hybrid model for the detection and classification task. The model employs YOLOv8 for the detection stage and an ensemble deep learning model that utilizes a majority voting strategy for fine-grained image classification. The proposed model aims to enhance the precision of classification by integrating classification models that have been trained with the same classes. This approach enables the utilization of the strengths of these classification models for a range of test instances. The experiment involved a diverse set of classes, encompassing a variety of types, including dogs, cats, birds, fruits, frogs, and foliage; each class is divided into subclasses for finer-grained classification, such as specific dogs, cat breeds, bird species, and fruit types. The experimental results show that the hybrid model outperforms classification approaches that use only one model, thereby demonstrating greater robustness relating to ambiguous complex images and uncontrolled environments. Full article

Background: Chiari-like malformation (CM) and syringomyelia (SM) are commonly observed conditions in Pomeranian dogs. Affected dogs may develop clinical signs that significantly impact quality of life. Therefore, it is crucial to select only unaffected dogs for breeding. However, the progression of CM/SM has not been fully elucidated. Dogs that are unaffected or mildly affected may progress to severe SM over time. The primary aim of this study is to investigate the progression of CM/SM through repeated MRI scans. A secondary objective is to evaluate the effect of furosemide treatment on syrinx sizes, given its frequent prescription. Methods: Pomeranians that underwent two CM/SM screenings between 2015 and 2025 were included. CM/SM classifications were assessed, and quantitative syrinx measurements were conducted. Maximum syrinx diameter (MSD) and maximum syrinx-to-spinal cord diameter ratio (MSD/SCD-r) were measured and documented. Dogs were classified based on the progression of SM. Furosemide treatment was documented, and its effect on syrinx size was compared with that in dogs not receiving furosemide. Results: At the time of the second MRI, 39.6% of dogs either developed SM or showed substantial progression, whereas 12.5% demonstrated partial recovery. Of the dogs initially classified as free from SM, 20.7% had developed the condition. A significant increase was observed in both MSD (p = 0.0058) and MSD/SCD-r (p = 0.0038) between MRI1 and MRI2. Notably, the change in MSD between MRI1 and MRI2 was statistically significantly smaller in dogs treated with furosemide compared to untreated dogs (p = 0.030). Conclusions: These findings indicate that syrinx dimensions are dynamic and may fluctuate over time, although a general trend toward progression is observed. Furthermore, furosemide may mitigate the progression of SM. Full article

This study introduces an innovative dog emotion classification system that integrates four non-invasive physiological indicators—skin potential (SP), muscle potential (MP), respiration frequency (RF), and voice pattern (VP)—with the extreme gradient boosting (XGBoost) algorithm. A four-breed dataset was meticulously constructed by recording and labeling physiological signals from dogs exposed to four fundamental emotional states: happiness, sadness, fear, and anger. Comprehensive feature extraction (time-domain, frequency-domain, nonlinearity) was conducted for each signal modality, and inter-emotional variance was analyzed to establish discriminative patterns. Four machine learning algorithms—Neural Networks (NN), Support Vector Machines (SVM), Gradient Boosting Decision Trees (GBDT), and XGBoost—were trained and evaluated, with XGBoost achieving the highest classification accuracy of 90.54%. Notably, this is the first study to integrate a fusion of two complementary electrophysiological indicators—skin and muscle potentials—into a multi-modal dataset for canine emotion recognition. Further interpretability analysis using Shapley Additive exPlanations (SHAP) revealed skin potential and voice pattern features as the most contributive to model performance. The proposed system demonstrates high accuracy, efficiency, and portability, laying a robust groundwork for future advancements in cross-species affective computing and intelligent animal welfare technologies. Full article

Background: Beagle dogs are widely used in biomedical research, but their genetic diversity and population structure require further investigation. This study aimed to assess genetic diversity, population structure, and selection signals in a foundational Beagle breeding population using genome-wide SNP genotyping. Methods: A total of 459 Beagle dogs (108 males, 351 females) were genotyped using the Canine 50K SNP chip. After quality control, 456 individuals and 31,198 SNPs were retained. Genetic diversity indices, principal component analysis (PCA), identity-by-state (IBS) distance, a genomic relationship matrix (G-matrix), runs of homozygosity (ROH), and Tajima’s D selection scans were analyzed. Results: The average minor allele frequency was 0.224, observed heterozygosity was 0.303, and expected heterozygosity was 0.305. A total of 2990 ROH segments were detected, with a mean inbreeding coefficient of 0.031. Phylogenetic analysis classified 106 stud dogs into 13 lineages. Selection signal analysis identified TTN (muscle function) and DLA-DRA, DLA-DOA, DLA-DMA (immune regulation) under selection. Conclusions: The Beagle population exhibits high genetic diversity and low inbreeding. To maintain genetic stability and ensure the long-term conservation of genetic resources, structured breeding strategies should be implemented based on lineage classifications. Full article

Abnormal trochlear morphology is one of the most important factors for patellar luxation occurrence in dogs, yet no studies have investigated its prevalence in the general population. This retrospective computed tomography study was designed to evaluate the trochlear groove morphology in four small dog breeds and the prevalence of trochlear dysplasia types according to Déjour’s classification depending on the breed, sex, and medial patellar luxation (MPL) presence and grade. A total of 174 joints (68 healthy, 96 grade II MPL, and 10 grade III MPL) from Mini-Pinschers, Yorkshire Terriers, Pomeranians, and Chihuahuas were included in the study. The morphological type of trochlear dysplasia (TD) was evaluated on axial scans and 3D reconstruction images according to the four-type classification of Déjour, sulcus angle, trochlear depth, and lateral/medial inclination angles. Of all 174 joints, 140 had trochlear dysplasia—all joints with MPL (n = 106) and 50% of healthy joints (n = 34). The classification of Déjour for trochlear dysplasia types (A, B, C, and D) corresponds to the morphology of the femoral trochlea in the studied small breeds of dogs. The results demonstrated three types of trochlear dysplasia according to Déjour: most commonly, type A, followed by type C, and most infrequently, type D. The Déjour type B was an incidental finding. The large proportion of clinically healthy joints with TD (50%) emphasises the significance of early trochlear morphology evaluation for the orthopaedical health of dogs from susceptible breeds, especially in female breeders. Full article

When classifying breeds of dogs, the accuracy of classification significantly affects breed identification and dog research. Using images to classify dog breeds can improve classification efficiency; however, it is increasingly challenging due to the diversities and similarities among dog breeds. Traditional image classification methods primarily rely on extracting simple geometric features, while current convolutional neural networks (CNNs) are capable of learning high-level semantic features. However, the diversity of dog breeds continues to pose a challenge to classification accuracy. To address this, we developed a model that integrates multiple CNNs with a machine learning method, significantly improving the accuracy of dog images classification. We used the Stanford Dog Dataset, combined image features from four CNN models, filtered the features using principal component analysis (PCA) and gray wolf optimization algorithm (GWO), and then classified the features with support vector machine (SVM). The classification accuracy rate reached 95.24% for 120 breeds and 99.34% for 76 selected breeds, respectively, demonstrating a significant improvement over existing methods using the same Stanford Dog Dataset. It is expected that our proposed method will further serve as a fundamental framework for the accurate classification of a wider range of species. Full article

Earlier, we described a breed-specific inflammatory myopathy in Dutch Kooiker dogs (Het Nederlandse Kooikerhondje), one of the nine Dutch breeds. The disease commonly manifests itself with clinical signs of difficulty walking, muscle weakness, exercise intolerance, and/or dysphagia. In nearly all dogs’ creatine kinase (CK) activity was elevated. Histopathology reveals the infiltration of inflammatory cells within the skeletal muscles. The objective of this study was to further investigate and characterize the histopathological changes in muscle tissue and immunophenotype the inflammatory infiltrates. FFPE fixed-muscle biopsies from 39 purebred Kooiker dogs were included and evaluated histopathologically according to a tailored classification scheme for skeletal muscle inflammation. As in other breed-related inflammatory myopathies, multifocal, mixed, and predominantly mononuclear cell infiltration was present, with an initial invasion of viable muscle fibres and the surrounding stroma leading to inflammation, necrosis, and tissue damage. Immunophenotyping primarily revealed lymphohistiocytic infiltrates, with CD3+ T-cells being the predominant inflammatory cell type, accompanied by CD8+ cytotoxic T-cells. The concurrent expression of MHC-II class molecules on myofibres suggests their involvement in initiating and maintaining inflammation. Additionally, CD20+ B-cells were identified, though in lower numbers compared to T-cells, and IBA-1-positive macrophages were frequently seen. These findings suggest a breed-specific subtype of polymyositis in Kooiker dogs, akin to other breeds. This study sheds light on the immune response activation, combining adaptive and innate mechanisms, contributing to our understanding of polymyositis in this breed. Full article

Most existing studies on pet breeds classification focus on images with simple backgrounds, leading to the unsatisfactory performance of models in practical applications. This paper investigates training pet breeds classification models using complex images and constructs a dataset for identifying breeds of pet cats and dogs. We use this dataset to fine-tune three SOTA models: ResNet34, DenseNet121, and Swin Transformer. Specifically, in terms of top-1 accuracy, the performance of DenseNet is improved from 89.10% to 89.19%, while that of the Swin Transformer is increased by 1.26%, marking the most significant enhancement. The results show that training with our dataset significantly enhances the models’ classification capabilities in complex environments. Additionally, we offer a lightweight pet breeds identification model based on PBI-EdgeNeXt (Pet Breeds Identification EdgeNeXt). We utilizes the PolyLoss function and Sophia optimizer for model training. Furthermore, we compare our model with five commonly used lightweight models and find that the proposed model achieves the highest top-1 accuracy of 87.12%. These results demonstrate that the model achieves high accuracy, reaching the SOTA level. Full article

Background: The aim of Part II of this two-part study is to describe and analyze the association of various aspects and measurements related to the morphometry of the skull and craniocervical region to CM/SM status of Pomeranians, by means of computed tomography (CT) and magnetic resonance imaging (MRI). Methods: Prospectively, Pomeranians were included that underwent both CT and MRI studies of the head and cervicothoracic vertebral column. For those cases where qualitative classifications differed between observers, the experienced observer re-evaluated the studies and decided on a final classification that was used for further analysis. For quantitative measurements, the means of the observers’ measurements were used for analysis. Results: Among statistically significant differences in measurements, we found that dogs with SM had a significantly shorter clivus length based on both MRI (p = 0.01) and CT measurements (p = 0.01), and a significantly smaller caudal cranial fossa area based on both MRI (p = 0.02) and CT measurements (p = 0.02). Conclusions: Significant morphometrical differences were identified between dogs with or without CM/SM. The findings in this study add to those already described in other breeds and provide further insight into factors that may play a role in the pathogenesis of CM/SM in Pomeranians. Full article

Mammary cancer is the most frequently diagnosed neoplasia in women and non-spayed female dogs and is one of the leading causes of death in both species. Canines develop spontaneous mammary tumors that share a significant number of biological, clinical, pathological and molecular characteristics with human breast cancers. This review provides a detailed description of the histological, molecular and clinical aspects of mammary cancer in canines; it discusses risk factors and currently available diagnostic and treatment options, as well as remaining challenges and unanswered questions. The incidence of mammary tumors is highly variable and is impacted by biological, pathological, cultural and socioeconomic factors, including hormonal status, breed, advanced age, obesity and diet. Diagnosis is mainly based on histopathology, although several efforts have been made to establish a molecular classification of canine mammary tumors to widen the spectrum of treatment options, which today rely heavily on surgical removal of tumors. Lastly, standardization of clinical study protocols, development of canine-specific biological tools, establishment of adequate dog-specific disease biomarkers and identification of targets for the development of new therapies that could improve survival and have less adverse effects than chemotherapy are among the remaining challenges. Full article

Background: The lung tissue in newborn canine neonates is still in a morphologically and functionally immature, canalicular–saccular stage. True alveoli are only formed postnatally. The aim of this study was to analyze the spatial and temporal development of the ventilation of the lung tissue in vital canine neonates during the first 24 h post natum (p.n.). Methods: Forty pups (birth weight Ø 424 g ± 80.1 g) from three litters of large dog breeds (>20 kg live weight) were included in the studies. Thirty-three pups (29 vital, 2 vitally depressed, 2 stillborn neonates) originated from controlled, uncomplicated births (n = 3); moreover, six stillborn pups as well as one prematurely deceased pup were birthed by other dams with delivery complications. Computed tomography (CT) was used in 39 neonates, and histopathologic tissue classification techniques (HALO) were used in 11 neonates (eight stillborn and three neonates died early post natum, respectively) to quantify the degree of aerated neonatal lung tissue. Results: It was shown that, in vital born pups, within the first 10 min p.n., the degree of ventilation reached mean values of −530 (±114) Hounsfield units (HU) in the dorsal and −453.3 (±133) HU in the ventral lung area. This is about 75–80% of the final values obtained after 24 h p.n. for dorsal −648.0 (±89.9) HU and ventral quadrants −624.7 (±76.8) HU. The dorsal lung areas were always significantly better ventilated than the ventral regions (p = 0.0013). CT as well as histopathology are suitable to clearly distinguish the nonventilated lungs of stillborns from neonates that were initially alive after surviving neonatal respiratory distress syndrome but who died prematurely (p = 0.0398). Conclusion: The results of this study are clinically relevant since the lung tissue of canine neonates presents an aeration profile as early as 10 min after birth and continues progressively, with a special regard to the dorsal lung areas. This is the basis for resuscitation measures that should be performed, preferably with the pup in the abdomen–chest position. Full article