Search Results (161)

Most research on domestic dog (Canis familiaris) behavior has focused on pets with restricted movement. However, free-ranging dogs exist in diverse cultural contexts globally, and their interactions with humans are less understood. Tourists can facilitate unrestricted dog movement into wilderness areas, where they may negatively impact wildlife. This study investigated which stimuli—namely, voice, touch, or food—along with inherent factors (age, sex, sociability) motivate free-ranging dogs to follow a human stranger. We measured the distance (up to 600 m) of 129 free-ranging owned and stray dogs from three villages in southern Chile as they followed an experimenter who presented them one of the above stimuli or none (control). To evaluate the effect of dog sociability (i.e., positive versus stress-related or passive behaviors), we performed a 30 s socialization test (standing near the dog without interacting) before presenting a 10 s stimulus twice. We also tracked whether the dog was in the company of other dogs. Each focus dog was video-recorded and tested up to three times over five days. Generalized linear mixed-effects models revealed that the food stimulus significantly influenced dogs’ motivation to follow a stranger, as well as a high proportion of sociable behaviors directed towards humans and the company of other dogs present during the experiment. Juveniles tended to follow a stranger more than adults or seniors, but no effects were found for the dog’s sex, whether an owner was present, the repetition of trials, the location where the study was performed, or for individuals as a random variable. This research highlights that sociability as an inherent factor shapes dog–stranger interactions in free-ranging dogs when food is given. In the context of wildlife conservation, we recommend that managers promote awareness among local communities and tourists to avoid feeding dogs, especially in the context of outdoor activities close to wilderness. Full article

Background/Objectives: Obesity is increasingly recognized as a global health concern due to its association with metabolic disorders and gut microbiota dysbiosis. While probiotics offer promise in regulating gut microbiota and improving host metabolism, strain-specific effects remain underexplored, particularly for canine-derived probiotics. This study aimed to isolate and characterize a novel probiotic strain, Ligilactobacillus animalis LA-1, and evaluate its anti-obesity effects and underlying mechanisms using a high-fat diet (HFD)-induced obese mouse model. Methods: LA-1 was isolated from the feces of a healthy dog and assessed for probiotic potential in vitro, including gastrointestinal tolerance, bile salt hydrolase activity, cholesterol-lowering capacity, and fatty acid absorption. Male C57BL/6J mice were fed either a standard chow diet or an HFD for 16 weeks, with HFD mice receiving oral LA-1 supplementation (2 × 10⁹ CFU/day). Multi-omics analyses, including 16S rRNA gene sequencing, short-chain fatty acid (SCFA) quantification, and untargeted liver metabolomics, were employed to investigate the effects of LA-1 on gut microbiota composition, metabolic pathways, and obesity-related phenotypes. Results: LA-1 supplementation significantly alleviated HFD-induced weight gain, hepatic lipid accumulation, and adipose tissue hypertrophy, without affecting food intake. It improved serum lipid profiles, reduced liver injury markers, and partially restored gut microbiota composition, decreasing the Firmicutes/Bacteroidetes ratio and enriching SCFA-producing genera. Total SCFA levels, particularly acetate, propionate, and butyrate, increased following LA-1 treatment. Liver metabolomics revealed that LA-1 modulated pathways involved in lipid and amino acid metabolism, resulting in decreased levels of acetyl-CoA, triglycerides, and bile acids. Conclusions: L. animalis LA-1 exerts anti-obesity effects via gut microbiota modulation, enhanced SCFA production, and hepatic metabolic reprogramming. These findings highlight its potential as a targeted probiotic intervention for obesity and metabolic disorders. Full article

Background: Dog agility is a rapidly growing sport involving a partnership between a dog and the handler, running through an obstacle course. Despite its increasing popularity and physical benefits, research on handler injuries remains limited. This study aimed to assess injury epidemiology of athletes practicing dog agility. Methods: This cross-sectional study was conducted using a comprehensive online survey consisting of 124 items, available in both English and Italian. The questionnaire was divided into four sections: Introduction collected demographic data and medical history; Materials and Methods focused on agility-related activities; Results explored injuries sustained in the past 12 months; Discussion examined training habits unrelated to agility. Results: Among 389 participants, the most represented age group ranged between 30 and 40 years old. Overall, 7% reported upper limb injuries, while 27% experienced at least one lower limb injury. Additionally, 20% of participants used medication, and 25% reported at least one chronic illness. On average, handlers trained twice per week and competed in two events per month. Lower limb injuries were predominantly muscular (49%) or ligamentous (14%) and most commonly occurred on grass pitches (56%). These injuries were more common in participants with a higher BMI, those using dynamic handling styles, and those competing at higher levels. Conclusions: This cross-sectional study highlighted the importance of identifying risk factors associated with dog agility handlers. Lower limb injuries were the most common, often associated with increased physical demands and handling styles involving intensive running and correlated with reduced physical fitness. Athletic conditioning, including structured warm-up and cool-down practices, might help decline injury risks. Full article

The mammalian immune system, including key components such as toll-like receptors (TLRs), lymphocytes, and cytokines, plays a vital role in defending against diseases. In dogs, genetic polymorphisms and epigenetic regulation of immune-related genes contribute to breed-specific differences in susceptibility or resistance to infectious, autoimmune, and inflammatory diseases. Cytokines, essential for immune cell differentiation and activation, exhibit variable expression among breeds due to genetic factors like single-nucleotide polymorphisms (SNPs) and miRNA regulation. This variability influences immune responses not only to infections but also to chronic inflammatory conditions and cancer, providing insights for improved diagnosis, treatment, and breeding. Selective breeding has further shaped diverse immune phenotypes across breeds, especially through genetic variations in the major histocompatibility complex (MHC) region, which affect vulnerability to immune-mediated and immunodeficiency disorders. Recent studies emphasize the role of specific miRNAs in modulating immune responses during parasitic and viral infections, opening new avenues for precision veterinary medicine and immunotherapy. This review highlights the genetic and epigenetic regulation of immune genes in dogs and explores their potential applications in advancing veterinary diagnostics, therapeutics, and breeding strategies to enhance canine health. Full article

Background/Objectives: The present study was aimed at documenting S. maltophilia occurrence in dogs with skin ailments, investigating its virulence, biofilm-forming ability, antimicrobial susceptibility, and zoonotic potential to inform preventive and therapeutic strategies against multidrug resistant S. maltophilia infections. Methods: Skin swabs (n = 300) were collected from dogs with dermatological ailments. Isolation was performed using selective media and confirmed with molecular methods, validated by MALDI Biotyper. Antimicrobial susceptibility testing and efflux activity assessment were conducted. Resistance genes related to sulfonamides, quinolones, and β-lactams were screened. Virulence was assessed by biofilm formation, motility, and virulence gene profiling. Results: In total, 15 S. maltophilia (5%) isolates were identified. All 15 isolates were susceptible to trimethoprim-sulfamethoxazole, enrofloxacin, gatifloxacin, levofloxacin, minocycline, and tigecycline, but resistant to cefpodoxime and aztreonam. The following resistance genes qnr (93.3%), bla_OXA-48 (46.7%), bla_KPC (33.3%), bla_NDM (33.3%), bla_CTX-M (20%), bla_SHV (20%), and bla_TEM (6.7%) were detected. All 15 isolates displayed high efflux activity. Overall, 9 isolates (60%) were strong biofilm producers, and 6 (40%) were moderate. Virulence genes such as virB, motA, rmlA, and fliC were present in all 15 isolates, with others varying in frequency. All isolates exhibited swimming motility. Heat map clustering showed diverse profiles, with no identical isolate patterns. Correlation analysis indicated positive associations between several antimicrobial resistance and virulence genes. Conclusions: This study underscores the zoonotic potential of S. maltophilia from dogs, advocating for a One Health approach to mitigate infection risks and limit the spread of virulent multidrug resistant pathogens. Full article

Background/Objectives: Primary pulmonary carcinoma (PC) is a malignant neoplasm that occurs in humans, dogs, and other species. In canine PC, palliative care remains the most practical approach for dogs with inoperable PC. Methods: We investigated the effectiveness of mammalian target of rapamycin (mTOR) inhibitors in canine lung cancer upon PI3K/AKT/mTOR activation. Three canine PC cell lines (AZACL1, AZACL2, and cPAC-1) were treated with three mTOR inhibitors (AZD8055, temsirolimus, and everolimus). In vitro, sensitivity assays were conducted to evaluate proliferation and Western blotting was used to examine pathway activation and phosphorylation of mTOR-related protein. Results: AZD8055 had a stronger inhibitory effect on cell proliferation than temsirolimus and everolimus in all three PC cell lines. The IC₅₀ for AZD8055 in the AZACL1, AZACL2, and cPAC-1 cell lines were 23.8 μM, 95.8 nM, and 237 nM, for temsirolimus they were 34.6 μM, 11.5 μM, and 11.2 μM, and for everolims they were 36.6 μM, 33.4 μM, and 33.0 μM, respectively. Western blotting revealed PI3K/AKT/mTOR pathway activation and differential phosphorylation of mTOR signal-related proteins across the three PC cell lines. In xenograft mice injected with the AZACL1 and AZACL2 cell lines we showed that the AZD8055-treated group exhibited a significant reduction in tumor volume via the inhibition of tumor growth compared to the control group. Conclusions: These findings reveal that the PI3K/AKT/mTOR pathway plays a key role in canine PC and that AZD8055 may be a novel therapeutic agent for PC-bearing dogs. Full article

Lyssaviruses are RNA viruses in the Family Rhabdoviridae, Genus Lyssavirus. They represent the causative agents of acute, progressive encephalitis, known historically as rabies. Regardless of specific etiology, their collective viral morphology, biochemistry, pathobiology, associated clinical signs, diagnosis, epizootiology, and management are essentially the same. Despite centuries of clinical recognition, these quintessential neurotropic agents remain significant pathogens today, with substantive consequences to agriculture, public health, and conservation biology. Notably, the singular morbidity caused by lyssaviruses is incurable and constitutes the highest case fatality of any viral disease. All warm-blooded vertebrates are believed to be susceptible. The dog is the only domestic animal that serves as a reservoir, vector, and victim. In contrast, felids are effective vectors, but not reservoirs. All other rabid domestic species, such as livestock, constitute spillover infections, as a bellwether to local lyssavirus activity. Frequently, professional confusion abounds among the veterinary community, because although the viral species Lyssavirus rabies is inarguably the best-known representative in the Genus, at least 20 other recognized or putative members of this monophyletic group are known. Frequently, this is simply overlooked. Moreover, often the ‘taxonomic etiology’ (i.e., ‘Lyssavirus x’) is mistakenly referenced in a biopolitcal context, instead of the obvious clinical illness (i.e., ‘rabies’). Global consternation persists, if localities believe they are ‘disease-free’, when documented lyssaviruses circulate or laboratory-based surveillance is inadequate to support such claims. Understandably, professional chagrin develops when individuals mistake the epidemiological terminology of control, prevention, elimination, etc. Management is not simple, given that the only licensed veterinary and human vaccines are against rabies virus, sensu lato. There are no adequate antiviral drugs for any lyssaviruses or cross-reactive biologics developed against more distantly related viral members. While representative taxa among the mammalian Orders Chiroptera, Carnivora, and Primates exemplify the major global reservoirs, which mammalian species are responsible for the perpetuation of other lyssaviruses remains a seemingly academic curiosity. This zoonosis is neglected. Clearly, with such underlying characteristics as a fundamental ‘disease of nature’, rabies, unlike smallpox and rinderpest, is not a candidate for eradication. With the worldwide zeal to drive human fatalities from canine rabies viruses to zero by the rapidly approaching year 2030, enhanced surveillance and greater introspection of the poorly appreciated burden posed by rabies virus and diverse other lyssaviruses may manifest as an epidemiological luxury to the overall global program of the future. Full article

Background: Renal injury is a critical health issue in pet dogs, often exacerbated by drug-induced nephrotoxicity such as gentamicin (GM). This study investigated the protective effects of ergosterol (Erg), a natural compound from edible mushrooms, against GM-induced damage in Madin–Darby canine kidney (MDCK) cells. Methods: MDCK cells were treated with GM (0.5–3 mmol/L) for 12 h to establish injury. Erg (1 to 32 μg/mL) was pretreated for 12 h before GM exposure (2 mmol/L). Cell viability, nitric oxide (NO), lactate dehydrogenase (LDH), oxidative stress markers (SOD, GSH, CAT, MDA), inflammatory cytokines (IL-1β, IL-6, TNF-α), renal function indicators (Scr, BUN), and autophagy/apoptosis-related proteins (ATG5, Beclin1, P62, BAX, BCL-2) were assessed via CCK-8, ELISA, fluorescence staining, and Western blot. Statistical significance (p < 0.05) was determined by ANOVA and LSD post hoc tests. Results: GM (2 mmol/L) significantly reduced cell viability (p < 0.01) and elevated NO and LDH levels (p < 0.01). Erg pretreatment (4–8 μg/mL) restored cell viability (p < 0.01), suppressed NO (p < 0.01) and LDH release (p < 0.01), and enhanced antioxidant enzyme activities (SOD, GSH, CAT; p < 0.01). Erg attenuated GM-induced reactive oxygen species (ROS) overproduction (p < 0.01) and decreased pro-inflammatory cytokines (IL-1β, IL-6, TNF-α; p < 0.01). Renal markers Scr and BUN were reduced (p < 0.01). Mechanistically, Erg upregulated autophagy proteins ATG5 and Beclin1 (p < 0.01), reduced P62 accumulation (p < 0.01), and lowered the BAX/BCL-2 ratio (p < 0.01). Conclusions: Erg protects MDCK cells from GM-induced nephrotoxicity by restoring autophagy flux, suppressing mitochondrial apoptosis, and mitigating oxidative stress and inflammation. These findings highlight Erg’s potential as a natural therapeutic agent for canine renal injury. Further in vivo studies are needed to validate its clinical efficacy. Full article

Sertoli cell-only (SCO) tubules are a histologic pattern characterized by the absence of germ cells within seminiferous tubules, leading to infertility in both humans and dogs. While its association with testicular tumors has been documented, the role of iron metabolism in SCO tubules remains unclear. This study investigates the immunolabeling of key iron-related proteins (Transferrin Receptor 1, Transferrin Receptor 2, and Ferritin Heavy chain 1) and Proliferating Cell Nuclear Antigen (PCNA) in canine SCO tubules within distinct microenvironments: seminomas, Sertoli cell tumors, and isolated. We confirm the presence and distribution of iron-related proteins in Sertoli cells as a part of a Sertoli cell-only pattern across different microenvironments. Our findings suggest a potential increase in iron uptake in association with tumors, and the cytoplasmic PCNA immunolabeling suggests a preferential activation of cell survival rather than proliferation, potentially facilitating neoplastic transformation. In contrast, Sertoli cells in the isolated Sertoli cell-only pattern exhibit nuclear PCNA immunolabeling, possibly correlated to the state of immaturity of Sertoli cells. These findings highlight the role of iron homeostasis and apoptosis in testicular tumorigenesis. Immunohistochemistry revealed that Sertoli cells in SCO tubules actively uptake iron in all conditions, yet their capacity to utilize it for proliferation appears restricted. Interestingly, PCNA labeling exhibits a pattern dependent on the microenvironment: in tumor-associated SCO tubules, it showed cytoplasmic localization, characteristic of an anti-apoptotic function, whereas isolated SCO tubules showed nuclear PCNA labeling, suggesting a potential role in DNA synthesis and repair. These findings highlight the interplay between iron homeostasis and cellular survival mechanisms, offering novel perspectives on its pathophysiology and implications for testicular cancer development. Full article

Background: According to the One Health concept, the physical proximity between pets and their owners facilitates the interspecies spread of bacteria including those that may harbor numerous antimicrobial resistance genes (ARGs). Methods: A shotgun sequencing metagenomic data-based bacteriome and resistome study of 1830 canine saliva samples was conducted considering the subsets of ARGs with higher public health risk, ESKAPE pathogen relatedness (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter species), and survey results on the physical and behavioral characteristics of the participating dogs. Results: A total of 318 ARG types achieved sufficiently high detection rates. These ARGs can affect 31 antibiotic drug classes through various resistance mechanisms. ARGs against tetracyclines, cephalosporins, and, interestingly, peptides appeared in the highest number of samples. Other Critically Important Antimicrobials (CIAs, WHO), such as aminoglycosides, fluoroquinolones, or macrolides, were among the drug classes most frequently affected by ARGs of higher public health risk and ESKAPE pathogen-related ARGs of higher public health risk. Several characteristics, including coat color, sterilization status, size, activity, or aggressiveness, were associated with statistically significant differences in ARG occurrence rates (p < 0.0500). Conclusions: Although the oral microbiome of pet owners is unknown, the One Health and public health implications of the close human–pet bonds and the factors potentially underlying the increase in salivary ARG numbers should be considered, particularly in light of the presence of ARGs affecting critically important drugs for human medicine. Full article

Human activities impact ecosystems globally, and understanding human–wildlife coexistence is crucial for species conservation. This study analyzed trends in local wildlife populations before and during the COVID-19 pandemic to assess their response to human disturbance. From 2017 to 2022, 60 camera sites were monitored, and seven species with the largest population size—excluding rodents—were selected for analysis. The results revealed that the presence of humans (p = 0.025) and domesticated animals (cats and dogs, p = 0.002) significantly decreased during the pandemic. Conversely, five species (except the Tibetan macaque and mainland serow) showed habitat expansion and population growth (p < 0.05), which may be related to their avoidance of human presence or artificial structures such as roads and tourism facilities. In addition, the analysis showed that most species, except the Tibetan macaque and wild boar, adjusted their activity patterns, showing increased diurnal activity when human disturbances were reduced (RR > 0). These findings suggest that species may adapt their behaviors to avoid human presence. This study highlights the negative impacts of human activities on local wildlife and emphasizes the need for stronger conservation and management efforts to mitigate human disturbances in scenic areas. Full article

The study of early dog domestication has been the focus of considerable scholarly interest in recent years, prompting extensive research aimed at pinpointing the precise temporal and geographic origins of this process. However, a consensus among studies remains elusive, with various research efforts proposing differing timelines and locations for domestication. To address the questions related to the domestication process, researchers have employed a wide range of methodologies, including genetic, biomolecular, morphometric, paleontological, biometric, and isotopic analyses, as well as dental wear analysis to reconstruct paleodiets. Each of these approaches requires access to fossil canid specimens, given that they work directly with the skeletal remains of dogs or wolves. Alternatively, some methods can yield insights into the domestication process without necessitating the physical remains of these canids. Taphonomy, for instance, enables the study of bone surfaces for tooth marks, which may serve as indirect indicators of carnivore activity, potentially attributable to dogs or wolves. This study applies a high-resolution taphonomic analysis to bones modified by carnivores at the prehistoric site of Peña Moñuz. Our aim is to identify the specific carnivores responsible for the observed bone modifications. The findings demonstrate the efficacy of this technique in identifying the agents of bite marks, suggesting that taphonomy may complement the paleogenetic, paleontological, and isotopic methodologies traditionally used to explore the origins of dog domestication Full article

The gut and the gut microbiome communicate with the nervous system through the gut–brain axis via neuroimmune and neuroendocrine mechanisms. Despite existing research, studies exploring this link in aging dogs are limited. This study aims to examine multiple blood and fecal biomarkers of intestinal health, along with various behavioral indicators based on saliva, blood, observations, and activity, in different age populations (junior: <2 y.o.; adult: 2–7 y.o.; senior: >7 y.o.) of thirty-seven Beagle dogs. In our study, Bacteroides were significantly higher in senior dogs. The relative abundance of Faecalibacterium and Blautia showed age-related trends, higher in senior and junior dogs, respectively. Fecal short-chain fatty acid concentration, especially acetate, increased with age, while propionate was higher in junior dogs. For the behavioral indicators we considered, blood thyroxine concentration, playing, exploring, and total activity were higher in junior dogs. The differences observed between the biomarkers of gut health and behavior, particularly those significant for the age correlations, emphasize the importance of considering age-related factors when studying the gut microbiome and behavior. However, further research is needed to better understand the mechanisms and specific pathways involved in the relationship between the studied biomarkers and age. Full article

Therapy dogs have been increasingly incorporated into a variety of medical treatment programs to improve patients’ treatment outcomes and wellbeing. However, research investigating the stress level of therapy dogs in this setting is limited. This is the first randomized–controlled and prospective study that investigated the wellbeing of therapy dogs in an inpatient stroke rehabilitation program. In this study, 14 therapy dog–handler pairs were embedded in an inpatient stroke rehabilitation program to provide animal-assisted treatment (AAT). These therapy dog–handler pairs actively participated in stroke rehabilitation by walking with the patient, playing fetch with the patient, and being petted/brushed by the patient, amongst various other AAT activities. To measure canine stress responses during the rehabilitation sessions, salivary cortisol and oxytocin concentrations, heart rate and heart rate variability, tympanic membrane temperature, and a behavioral evaluation were recorded before and after interactions with the patient. The results demonstrated that therapy dogs had significantly decreased heart rate and increased heart rate variability after the AAT session. Right tympanic temperature significantly increased after the session, but there was no significant difference in terms of salivary cortisol or oxytocin levels, nor in stress-related behavioral evaluations after the AAT session. Taken together, the results suggest that incorporating AAT into an inpatient stroke rehabilitation program did not induce stress in the therapy dogs, and that the therapy dogs may have been more relaxed after the session. Full article

Background/Objectives: Aronia extract or its active compounds, especially anthocyanin, have shown potential for Alzheimer’s disease (AD)-related pathologies, including neuroinflammation, fibrillogenesis of amyloid beta (Aβ), and cognitive impairment. However, there was still concern about their structural instability in vivo and in vitro. To solve the instability of anthocyanins, we combined aronia bioactive factions (ABFs) and alginic acid via electrostatic molecular interactions and created an ABF–alginic acid nanocomplex (AANCP). We evaluated whether it is more stable and effective in cognitive disorder mice and neuroinflammation cell models. Methods: The physicochemical properties of the AANCP, such as nanoparticle size, structural stability, and release rate, were characterized. The AANCP was administered to scopolamine-injected Balb/c mice, and to BV2 microglia treated with lipopolysaccharide (LPS) and amyloid beta (Aβ). Inflammation responses were measured via qPCR and ELISA in vitro, and cognitive functions were measured via behavior tests in vivo. Results: The AANCP readily formed nanoparticles, 209.6 nm in size, with a negatively charged zeta potential. The AANCP exhibited better stability in four plasma samples (human, dog, rat, and mouse) and was slowly released in different pH conditions (pH 2.0, 7.4, and 8.0) compared with non-complexedABF. In vitro studies on microglial cells treated with AANCPs revealed a suppression of inflammatory cytokines (tumor necrosis factor-alpha and interleukin-6) induced by LPS. The AANCP increased microglial Aβ phagocytosis through the activation of triggering receptor expressed on myeloid cell 2 (TREM2)-related microglial polarization. The AANCP inhibited aggregation of Aβ in vitro and alleviated cognitive impairment in a scopolamine-induced in vivo dementia mouse model. Conclusions: Our data indicate that AANCPs are more stable than ABFs and effective for cognitive disorders and neuroinflammation via modulation of M2 microglial polarization. Full article