Veterinary Quarterly最新文献

The genus Listeria is heterogeneous and contains pathogenic and nonpathogenic species. Pathogenic L. monocytogenes and L. ivanovii have different environmental distributions, infect different hosts, and cause distinct syndromes. Here, we evaluated whether responses of different Listeria species to diverse host niches contribute to virulence heterogeneity and influence their environmental distribution. We assessed resistance to gastric and intestinal fluids, gut and uterus microbiota, and semen. L. monocytogenes was more resistant than L. ivanovii in gastric fluid, whilst L. seeligeri and L. valentina showed an intermediate phenotype. All the tested Listeria species resisted the intestinal fluid. Gut microbial communities outcompeted and eliminated L. ivanovii and L. valentina. However, L. monocytogenes and L. seeligeri outcompeted intestinal commensal bacteria. Our findings suggest that, unlike L. monocytogenes and L. seeligeri, the tested L. ivanovii are unlikely to colonize the gastrointestinal tract of ruminants, which would reduce replication, fecal shedding, and environmental distribution. However, the ability of L. ivanovii to survive within uterine microbiota and semen suggests that the tested clones could persist in the urogenital tract of ruminants. Then venereal transmission could be more probable than the oral route, which could explain why L. ivanovii is associated with abortion outbreaks and not encephalitic cases.

Canine mammary tumors (CMTs) are the most common neoplasms in intact female dogs, yet early detection remains challenging due to the lack of clinically validated, noninvasive biomarkers. This study aimed to develop a noninvasive diagnostic model for CMT detection by integrating serum autoantibody biomarkers with machine learning. Serum samples from 154 dogs with mammary tumors (31 benign, 123 malignant) and 39 healthy controls were analyzed using a custom multiplex immunoassay detecting autoantibodies against AGR2, HAPLN1, IGFBP5, and TYMS, normalized to anti-BSA levels. Median fluorescence intensity (MFI), standardized autoantibody ratios, and their combination, together with clinical variables, were used to train random forest classifiers. The model based on standardized autoantibody ratios achieved the best performance, with an AUC of 0.79 (sensitivity 75.3%, specificity 74.4%) for overall CMT detection; 0.78 (92.7%, 61.5%) for malignant CMTs; and 0.77 (82.2%, 71.8%) for early-stagemalignancies. Assuming a CMT prevalence of 0.5 in the hospital-referred population, the positive and negative predictive values ranged from 0.74-0.75 and 0.75-0.91, respectively. This proof-of-concept study demonstrates that a machine learning-assisted multiplex autoantibody assay offers a feasible noninvasive approach for CMT detection. Further validation in larger, independent cohorts is warranted to support clinical translation in veterinary oncology.

While thyroid physiology has been studied in domestic ruminants, many uncertainties remain. In fact, this metabolism is rarely assessed in routine veterinary practice, and diseases of the thyroid gland or its metabolism are poorly documented in domestic ruminants. This scoping review aims to summarize current knowledge in anatomy, physiology, diseases, and diagnostic methods related to thyroid function in domestic ruminants. A structured research methodology was followed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) extension for scoping reviews. Four databases were used: CAB Abstracts, Embase, PubMed and Scopus. Selection and screening process of the identified studies, as well as data extraction, were managed using Covidence software. Finally, 206 studies were included. Most studies involved cattle (n = 104), followed by sheep (n = 65) and goats (n = 28). The main study topic was on thyroid physiology (n = 127), followed by diseases (n = 48), diagnostic methods (n = 22) and histology (n = 9). Although many studies addressed the anatomy and physiology of the thyroid gland, few confirmed the euthyroid status (having a normally functioning thyroid gland) of these animals, warranting cautious interpretation of the results. Hypothyroidism is the most documented thyroid disease in ruminants, predominantly caused by iodine deficiency. The physiology of the thyroid gland has been extensively studied in relation to heat stress, reproduction, animal production and nutrition. However, there is much less literature available on diseases described in domestic ruminants and their diagnostic methods. Diagnostic tools for assessing thyroid metabolism in ruminants include assays for total thyroxine, total triiodothyronine, bovine thyroid stimulating hormone, total serum iodine, milk iodine, urine iodine, and plasmatic inorganic iodine.

Ex situ conservation is an important wildlife conservation strategy, but endangered wildlife in captivity often exhibit high disease rates. Commensal microorganisms are vital for homeostasis, immunity, and linked to diseases. This study analyzed the structure, assembly, variations of the symbiotic microbiota of the endangered crocodile lizard, and their relationship with environment, as well as the effects of captivity on them, to explore why captive reptiles face high dermatosis rates. Results showed that the reptile's microbiota significantly differ from that of its habitat, demonstrating niche specificity. While species richness among organs showed no significant differences, microbial diversity varied considerably. Skin microbiota showed no site-specific clustering. The assembly of skin, oral, and intestinal bacterial communities was dominated by homogeneous selection. The gut and oral bacterial networks were resilient to disturbances, while the skin bacterial network was sensitive. Captivity primarily affected the skin microbiota, reducing its diversity and stability, thereby increasing disease risk, and these effects were not solely attributable to environmental changes. These findings suggested that skin microbial changes in captive reptiles may be responsible for their increased susceptibility to dermatosis in ex situ conservation. This study underscored the importance of understanding reptile-associated microbes for effective conservation strategies and offers potential solutions.

This review examines the role of the canine blood-brain barrier (BBB) in health and disease, focusing on the impact of the multidrug resistance (MDR) transporter P-glycoprotein (P-gp) encoded by the ABCB1/MDR1 gene. The BBB is critical in maintaining central nervous system homeostasis and brain protection against xenobiotics and environmental drugs that may be circulating in the blood stream. We revise key anatomical, histological and functional aspects of the canine BBB and examine the role of the ABCB1/MDR1 gene mutation in specific dog breeds that exhibit reduced P-gp activity and disrupted drug brain pharmacokinetics. The review also covers factors that may disrupt the canine BBB, including the actions of aging, canine cognitive dysfunction, epilepsy, inflammation, infection, traumatic brain injury, among others. We highlight the critical importance of this barrier in maintaining central nervous system homeostasis and protecting against xenobiotics and conclude that a number of neurological-related diseases may increase vulnerability of the BBB in the canine species and discuss its profound impacts on canine health.

Chronic Kidney Disease (CKD) is one of the most common conditions affecting felines, yet the metabolic alterations underlying its pathophysiology remain poorly understood, hindering progress in identifying biomarkers and therapeutic targets. This study aimed to provide a comprehensive view of metabolic changes in feline CKD across conserved biochemical pathways and evaluate their progression throughout the disease continuum. Using a multi-biomatrix high-throughput metabolomics approach, serum and urine samples from CKD-affected cats (n = 94) and healthy controls (n = 84) were analyzed with ultra-high-performance liquid chromatography-high-resolution mass spectrometry. Significant disruptions were detected in tryptophan (indole, kynurenine, serotonin), tyrosine, and carnitine metabolism, as well as in the urea cycle. Circulating gut-derived uremic toxins, including indoxyl-sulfate, p-cresyl-sulfate, and trimethylamine-N-oxide, were markedly increased, primarily due to impaired renal excretion. However, alternative mechanisms, such as enhanced bacterial formation from dietary precursors like tryptophan, tyrosine, carnitine, and betaine, could not be ruled out. Overall, the findings suggest that metabolic disturbances in feline CKD are largely driven by the accumulation of gut-derived uremic toxins derived from precursors highly abundant in the feline diet. These insights may link the strict carnivorous nature of felines to CKD pathophysiology and highlight potential avenues for studying preventive or therapeutic interventions.

Study advances current diagnostic efficiency of canine/feline (sub-)cutaneous tumors using machine learning and multimodal imaging data. White light (WL), fluorescence (FL) and ultrasound (US) imaging were combined into hybrid approaches to differentiate between malignant mastocytomas, soft tissue sarcomas and benign lipomas. Support Vector Machine and Ensemble classifiers were optimized via sequential feature selection. US radio-frequency signals were quantitatively analyzed to derive the colormaps of six US estimates, corresponding to spectral and temporal domains of the acoustic field. This resulted in the quantification of 72 morphological features for US; as well as 24 and 12 - for WL and FL data, respectively. Resulting classification efficiency for mastocytoma and sarcoma using US data was >75%; US+FL - 75-80%; US+WL - 85-90% and US+OPTICS - 90-95%. ∼100% classification efficiency was achieved for the differentiation between benign and malignant tumors even using single WL feature for Ensemble classifier. US features, resulting in inferior classification efficiency, were competitive to superior optical, as they were selected during optimization to be added to or replace optical counterparts. Additional tissue differentiation was performed on z-stacks of US colormaps, obtained using 3D arrays of US radio-frequency signals. This resulted in ∼70% differentiation efficiency for mastocytoma and sarcoma as well as >95% for benign and malignant tissues. The obtained additional metric of classification efficiency provides complementary diagnostic support, which for Support Vector Machine can be expressed as: 90.3 ± 1.9% (US+WL)×71.2 ± 0.6% (US_{Depth Profile}). This hybrid criterion adds robustness to diagnostic model and may be very beneficial to characterize heterogeneous tissues.

Senecavirus A (SVA) is the causative agent associated with porcine idiopathic vesicular disease (PIVD), a condition indistinguishable from other foreign vesicular diseases affecting pigs. This complicates differential diagnosis and impacts the global swine industry. A diagnostic ELISA based on a non-structural viral protein has been developed, capable of distinguishing infected from vaccinated animals (DIVA). Different expression systems (eukaryotic and prokaryotic) were used to express recombinant proteins. The baculovirus-expressed SVA 3AB DIVA ELISA demonstrated a sensitivity of 96.67% and specificity of 96.67%. In contrast, the E. coli-expressed SVA 3AB DIVA ELISA achieved 100% sensitivity and 93.33% specificity. Both ELISAs strongly correlated with the reference method and showed no cross-reactivity with other pig pathogens. The E. coli system also provided a higher yield of expressed protein than the baculovirus system. These findings indicate that SVA DIVA ELISAs are effective alternatives for detecting SVA antibodies. They can be valuable tools for sero-surveillance and for evaluating immunity status tests to support and approve vaccination programs for pig herds in the future.

Since their emergence in Guangdong, China, in 1996, Gs/GD H5 highly pathogenic avian influenza viruses (HPAIVs) have diversified into multiple clades, spreading globally through wild bird migrations and causing substantial losses in poultry and wildlife. In South Korea, HPAIVs, including H5N1, H5N8, and H5N6 subtypes, have been repeatedly introduced since 2003. This review examines the epidemiology, genetic characteristics, and pathobiological features of these viruses in South Korea. Outbreaks typically occur between October and December, aligning with the arrival of wintering migratory birds. While outbreaks in poultry farms dominated before 2018, wild bird cases became more prevalent in subsequent years. Seasonal outbreaks in poultry have declined, but large-scale mortality events in wild birds emerged biennially from 2020. Genotypic diversity has increased since 2014 due to reassortment with low pathogenic viruses, with novel genomic traits detected in recent seasons. Infection studies show consistently fatal outcomes in chickens, while high mortality in domestic ducks was observed only with two of the studied strains, despite efficient transmission. Wild bird studies reveal species-specific roles in viral shedding and transmission. This review underscores the dynamic nature of HPAI outbreaks, highlighting the importance of surveillance, biosecurity, and genetic and pathogenicity analyses to mitigate future risks.

In this study, a commercially available Salmonella Typhimurium vaccine (Vaxsafe ST) reconstituted in either water or nutrient broth, was tested to understand its effects on the in vitro invasion of Caco-2 cells and its transcriptional regulation post-reconstitution. Over time, the invasiveness of Vaxsafe ST was significantly higher following reconstitution in nutrient broth compared with water. Incubation temperature post-reconstitution did not significantly affect the invasion rate. Transcriptome data showed that Vaxsafe ST reconstituted in nutrient broth upregulated genes involved in the two-component system and flagella activity pathways; however, genes involved in host colonization and invasion were unaltered. Genes involved in host colonization and invasion were downregulated after reconstitution in water. Vaxsafe ST reconstituted in a nutritive diluent improved the metabolic activities of the vaccine. The animal experiment demonstrated that vaccine colonization was significantly higher in caeca compared with ileum irrespective of the diluent. Incubating the vaccine in nutrient broth for 30 min before administration did not significantly increase its colonization or organ invasion in chicks. Overall, the findings support the use of nutritive media for the reconstitution of Vaxsafe ST, warranting further investigation to optimize vaccine performance. This study provides a foundation for future work on vaccine reconstitution strategies.