Biology and Life Sciences

Abstract: Background: Whole-blood transcriptomics captures systemic responses to infectious diarrhea, but pooled public-dataset reanalysis can be confounded by leukocyte composition and does not by itself establish cell-intrinsic regulation. Methods: We performed a profile-level secondary analysis of GSE69529 (255 profiles from 246 children; 203 diarrhea and 52 control profiles, including nine repeated profiles) using differential expression, functional enrichment, exploratory network analysis, promoter-sequence analysis, motif discovery, and transcription-factor activity inference. Because the pooled GEO2R contrast did not adjust for leukocyte composition, age, sex, pathogen, or repeated-subject structure, differentially expressed genes were interpreted as a composite whole-blood response. Published results from GSE276395 were used only for cross-study concordance, not as an independently reanalyzed validation dataset. Results: The pooled analysis identified 7,050 genes at adjusted P < 0.05 among 15,740 analyzed genes and highlighted broad immune, RNA-processing, cell-cycle, intracellular-organization, apoptosis, trafficking, and metabolic programs. Promoter composition was similar between regulatory directions; no HOCOMOCO motif was supported by AME, no STREME motif met the prespecified E-value threshold, and no CollecTRI-ULM transcription factor remained significant after false-discovery-rate correction. GSE276395 showed concordant innate-immune, neutrophil-centered, and immunometabolic themes, whereas its recurrent 12-gene set did not overlap the 12-gene discovery-stage panel. Conclusions: The reproducible signal is broad pathway-level whole-blood remodeling. Gene-, motif-, and regulator-level findings are exploratory, and the present design cannot distinguish shifts in leukocyte composition from within-cell transcriptional regulation.

Abstract: This study assessed how ruminal volatile fatty acid (VFA) biomarkers—acetic acid, propionic acid, the acetate-to-propionate ratio (A:P), and total VFA—relate to average daily gain (ADG) in growing sheep and goats, and whether they add predictive value beyond conventional covariates. A systematic search identified 85 studies with 290 treatment groups; complete data were available for 83 studies with 283 treatment groups (total VFA: 82 studies, 279 treatment groups). Two analytic strategies were used: multilevel meta-regression with inverse-variance weighting and an unweighted mixed linear model as a confirmatory check, with adjustment for dry matter intake, initial body weight, crude protein, neutral detergent fiber, and species. Under inverse-variance weighting with cluster-robust inference, acetic acid (β = 0.00088, robust P = 0.003), propionic acid (β = 0.00188, robust P < 0.001), and total VFA (β = 0.00088, robust P < 0.001) were positively related to ADG, explaining 0.583, 0.621, and 0.625 of heterogeneity, respectively; each added limited but positive explanatory value beyond covariates (0.017, 0.107, and 0.083). A:P did not reach significance under cluster-robust inference (robust P = 0.074) and behaved inconsistently in the mixed linear framework (P = 0.015). Results were consistent in the mixed linear framework (marginal R² = 0.610–0.642). Leave-one-out cross-validation showed propionic acid gave the largest cross-study predictive gain (overall ΔCV-R² = 0.124, 95% CI 0.012–0.326; RMSE reduced 10.84%; goats ΔCV-R² = 0.441, 95% CI 0.035–1.337; RMSE reduced 14.92%). No significant slope difference between sheep and goats was detected. In conclusion, acetic acid, propionic acid, and total VFA are robustly associated with ADG, but their incremental explanatory power for inter-study heterogeneity is modest; propionic acid offers the largest and most stable cross-study predictive increment, whereas A:P is unreliable. The models are suited to estimating mean treatment-group performance under similar conditions, pending external validation.

Abstract: Background: Public policies are increasingly judged not only by their support for production but by how they shape trade structure, value distribution and resilience to shocks. Romania's sheep sector has expanded since EU accession, yet whether this has translated into higher-value exports or more resilient trade destinations remains unclear. Methods: Using UN Comtrade, FAOSTAT and Eurostat data for 2003–2024, four dimensions — production base, trade orientation, value structure and geographical concentration — were examined via descriptive indicators, Kendall trend tests, permutation Kruskal–Wallis comparisons across five policy periods, and one-sided sign and Wilcoxon tests, with robustness checks in constant prices. Results: The sheep population grew 42.8% (2003–2024), but slaughter and meat production did not follow proportionally, and the Slaughter Rate fell from 83.6% to 51.1%. Live Export Value Share exceeded 50% every year (median 92.2%), and live export value exceeded meat export value in all 22 years (median ratio 11.8). Eight of fourteen indicators differed significantly across policy periods, and geographical concentration was confirmed for meat but not live-animal exports. Conclusions: The sector combines an expanding productive base with a persistently live-animal-centric export structure; policy should complement production support with investment in slaughter and processing capacity, quality classification and market diversification, rather than restricting live exports.

Abstract: Livestock ammonia (NH₃) is the volatile expression of incomplete nitrogen retention and microbial transformation of excreta. It links feed formulation, housing microclimate and manure handling with indoor air quality, animal welfare, occupational exposure, fine particulate matter and ecosystem nitrogen loading. This review examines NH₃ formation and emission dynamics, distinguishes concentration from mass flux, synthesizes animal and human health outcomes, and evaluates mitigation across the feed-to-field nitrogen cascade. Urea or uric acid conversion supplies ammoniacal nitrogen, whereas pH, temperature, moisture, residence time, exposed area and airflow govern volatilization. Controlled animal studies demonstrate ocular, respiratory, metabolic, behavioural and production responses that depend on concentration and exposure duration; livestock workers and neighbouring communities encounter NH₃ within complex mixtures containing dust, endotoxin and other pollutants. Effective management therefore requires multiple barriers: precision protein nutrition, rapid excreta removal, litter and slurry stabilization, ventilation integrated with capture, covered storage and low-emission land application. Recent studies show that climate warming can erode mitigation performance and that housing design, seasonal ventilation and practical amendments materially alter emissions. Whole-system assessment must track nitrogen, co-pollutants, animal outcomes, worker exposure, cost and downstream fate. It proposes a measurement framework and research priorities for durable, health-protective and circular nitrogen management.

Abstract: This study evaluated whether calcium-protected oil and cornmeal modulate metabolic–endocrine integration and growth in tropical dairy heifers. Four diets were tested: R1, 60% roughage + 40% concentrate; R2, R1 + 4% Ca-oil; R3, R1 + 4% cornmeal; and R4, R1 + 2% Ca-oil + 2% cornmeal, with four heifers per treatment. We assessed blood biomarkers over two months using one-way ANOVA of individual means, and analysed weekly growth with linear mixed-effects models. Diet affected erythrocytes, haemoglobin, MCV, MCH, MCHC, RDW-CV, eosinophils, HDL-cholesterol, total protein, and albumin (p < 0.05). In contrast, most leukocytes, energy metabolites, reproductive hormones, growth-related hormones, and cortisol were unchanged. R4 showed the most prominent erythrocyte, haemoglobin, and total-protein profile without increased NEFA, BHBA, or cortisol. Body size increased over time (p < 0.001), with a treatment × week interaction for body length (p = 0.014). Average daily gain correlated positively with IGF-1 (r = 0.602; p = 0.014) and negatively with NEFA (r = −0.506; p = 0.045). Thus, combined Ca-oil and cornmeal mainly influenced haematological capacity and circulating protein status while maintaining broad metabolic and endocrine stability.

Abstract: Axenic and gnotobiotic aquatic animals provide direct experimental access to the causal roles of microorganisms in host development, physiology, nutrition, immunity and disease. Fish are particularly manageable because fertilization and embryogenesis occur externally, therefore, embryos can be disinfected before hatching, and the larvae can be maintained in sterile water. Zebrafish is currently the most studied and well-established fish axenic or gnotobiotic model, but methods have also been established for medaka and aquaculture species such as: Rainbow trout, European sea bass and Atlantic cod. This narrative review evaluates the practical and conceptual basis of axenic aquatic animal research, with emphasis on fish production, rearing and handling. It compares representative derivation procedures, sterile culture formats, feeding strategies, water-quality constraints and sterility assays, and it examines how these methodological choices affect biological interpretation. The absence of microbiota alters intestinal differentiation, epithelial proliferation, innate immune maturation, lipid handling, bile-salt signaling and behavior in zebrafish, while studies in farmed fishes demonstrate the value of gnotobiotic models for testing colonization resistance, probiotics and pathogen-host interactions. Evidence from Daphnia and Artemia further shows that aquatic gnotobiology is also useful and can resolve microbiota-dependent effects on organism’s health, dietary responses and disease resistance. A central conclusion is that “axenic” is an operational microbiological state rather than an absolute biological property, as confidence intervals depend on sampling design and orthogonal detection. The review therefore proposes minimum reporting and quality-control practices, including vessel-level replication, longitudinal sterility testing, feed validation, contamination rules and appropriate recolonization controls. These standards are essential if axenic or gnotobiotic aquatic models are to produce reproducible mechanistic results.

Abstract: Sulfated chitosan (ChS) is a chemically modified chitosan derivative with structural and electrostatic features that mimic selected properties of heparan sulfate (HS) and has emerged as a promising antimicrobial biomaterial. Piscirickettsia salmonis, the etiological agent of salmonid rickettsial septicemia (SRS), is a major bacterial pathogen in salmon aquaculture and a principal driver of antibiotic use in Chile. In this study, we evaluated the in vitro antibacterial and antibiofilm activity of ChS against P. salmonis EM-90 and its interaction with florfenicol (FF) and oxytetracycline (OTC). ChS exhibited a minimum inhibitory concentration (MIC) of 750 µg/mL. Checkerboard assays showed a synergistic interaction between ChS and OTC (ΣFIC = 0.313) and an additive interaction between ChS and FF (ΣFIC = 0.703). Re-inoculation assays indicated predominantly reversible growth inhibition for several inhibitory combinations. LIVE/DEAD™ fluorescence analysis revealed a time-dependent increase in membrane permeabilization following ChS exposure, with a significant 37–63% reduction in the Green/Red fluorescence ratio between 5 and 48 h (p < 0.05). Consistently, scanning electron microscopy (SEM) revealed morphological alterations in ChS-treated bacteria, including irregular and eroded cell surfaces and focal depressions, which were more pronounced than those observed with chitosan without chemical modifications. ChS also significantly inhibited biofilm formation, with reductions exceeding 80% at day 6 and 57% at day 8 (p < 0.05), and altered biofilm architecture, abundance, and spatial distribution at days 6 and 10. Collectively, these findings demonstrate that ChS exerts antibacterial and antibiofilm effects against P. salmonis EM-90 and enhances its in vitro susceptibility to OTC and FF. The membrane alterations induced by ChS provide a plausible mechanistic basis for its antibiotic-potentiating activity, although enhanced intracellular antibiotic uptake was not directly demonstrated. These results support further investigation of ChS as an HS-mimetic biopolymer and complementary antimicrobial strategy for SRS control.

Abstract: Rangelands are critical ecosystems sustaining both livestock production and wildlife populations. This review explores the complex interactions between farmers, livestock, and wildlife within rangeland systems. Overgrazing, habitat fragmentation, and human-wildlife conflict pose significant challenges, while sustainable grazing, rotational systems, and collaborative management offer pathways to balance productivity and conservation. Evidence suggests that moderate stocking rates and adaptive management enhance biodiversity while maintaining livelihoods. Integrated approaches are essential for long-term sustainability.

Abstract: The liver is the primary organ for xenobiotic biotransformation, and its functional integrity dictates not only the elimination rate of drugs but also their ultimate pharmacodynamic profile. The superfamily of hemecontaining monooxygenases, cytochrome P450 (CYP), underpins the oxidative metabolism of approximately 75% of all veterinary drugs. A critical component of the microsomal electron transport chain is NADPHcytochrome P450 reductase. Each hepatobiliary pathology differentially affects CYP expression and activity, leading to distinct pharmacodynamic alterations. Species differences complicate pharmacodynamic adjustments. Sex, diet, and gut microbiota also modulate CYP expression and thus pharmacodynamics. The aim of the present work was to systematically collate available data on activity and expression changes of major CYP isoforms and CYPOR in key veterinary species under various hepatobiliary conditions, and to translate these changes into clinically relevant pharmacodynamic predictions. A systematic literature search was performed in PubMed, Scopus, Web of Science, and Google Scholar covering the period from 1990 to 2026. This comprehensive review demonstrates that hepatobiliary pathologies in animals elicit qualitatively distinct alterations in the CYP system and its redox partner CYPOR, leading to drugspecific pharmacodynamic changes. The integrated dysbalance index can guide clinicians: values &gt;0.7 indicate an acute mismatch requiring antioxidants and caution with prodrugs; values &lt;0.15 signal a systemic electron deficit mandating substantial dose reductions for all CYPdependent drugs. Speciesspecific patterns: cats’ vulnerability to CYP2E1 substrates, horses’ pronounced CYPOR decline in cholestasis, and dogs’ paradoxical CYP2C induction in steatosis, must be incorporated into dosing algorithms.

Abstract: Background: Owners often report that Poodles and Poodle-crosses are “fussy eaters”, and Labrodors and Labrador-crosses are the opposite, however there are no large scale studies looking at breed differences in food intake and “fussiness”. Aims To analyse a large database of dog records to identify any differences in eating habits between Poodles and Labradors compared to a general population. Methods Dog owners registering with a pet food company completed a Likert scale questionnaire on their dog’s eating habits. Results: Over 615,000 canine records were analysed. In a dataset from 2017-2021 Poodles and their crosses had a significantly higher degree of “fussiness”, to non-Poodle breeds (p <0.001). A dataset from 2022-2024 across all 5 European countries the dataset showed 61.3% of Poodles and their crosses were “very fussy” or “fussy eaters” significantly higher (p <0.001) than non-Poodle breeds of which 46.7% were “very fussy” or “fussy” eaters. From a 2022-2024 dataset Labradors represented 20.0% were good eaters and 44% “foodies” compared to non-Labradors (p < 0.001) Conclusion Poodles and their crosses are significantly more likely to be “fussy eaters” than non-Poodle breeds. Labradors are significantly more likely to be a “foodie” and will eat just about anything. Further studies are needed to determine why Poodles and their crosses are predisposed to be “fussy eaters”.

Abstract: Mycobacterium avium subsp. paratuberculosis (MAP) causes Johne’s disease in ruminants and is difficult to control once persistent infection is established. We designed a MAP multi-epitope vaccine candidate by screening conserved proteins and assembling predicted B-cell, MHC class I-restricted cytotoxic T lymphocyte (CTL), and MHC class II-restricted helper T lymphocyte (HTL) epitopes into a recombinant construct. The construct was examined by physicochemical analysis, structural modeling, molecular docking, and immune simulation, then expressed in Escherichia coli and tested in BALB/c mice as a recombinant protein without external adjuvant or as an exploratory MYY-containing formulation, alongside PBS and inactivated-MAP controls. RAW264.7 macrophages were stimulated with the purified recombinant protein for RNA sequencing. Seven proteins were retained as antigen sources, and the final construct contained five B-cell epitopes, ten CTL epitopes, and seven HTL epitopes. Immunized mice produced antigen-specific IgG, IgG1, and IgG2a, and antigen-restimulated splenocytes secreted higher levels of IFN-γ, IL-2, TNF-α, and IL-17. In macrophages, recombinant-protein stimulation changed gene-expression profiles and enriched pathways related to cytokine-cytokine receptor interaction, NF-κB, TNF, IL-17, Toll-like receptor, and NOD-like receptor signaling. The construct was immunogenic in mice; the exploratory MYY-containing formulation showed higher immune-response readouts in this experimental setting, but this adjuvant-associated observation requires further validation and protection against MAP infection still needs to be tested in challenge experiments and target animals.

Abstract: Kobuviruses are emerging enteric pathogens with broad host ranges, yet their pathogenic potential in wild large felids remains largely unexplored. Here, we report the first case of fatal systemic infection caused by a novel Aichivirus A (AiV-A) strain, designated FeKoV0813, in a captive juvenile white lion (Panthera leo). The animal presented with acute respiratory distress and severe diarrhea, culminating in death despite supportive care. Comprehensive diagnostic workflows, including necropsy, histopathology, fluorescence in situ hybridization (FISH), and absolute quantitative RT-PCR, were employed to determine tissue tropism and viral dissemination. Whole-genome sequencing, phylogenetic analysis, and selection pressure assessment were conducted to characterize the viral evolutionary dynamics and host-specific constraints. The 8,213-nucleotide genome exhibited typical Kobuvirus organization, clustering within the Aichivirus A clade alongside carnivore-derived strains from dogs, cats, and foxes. High viral RNA loads were detected primarily in the small intestine (~7.4 log₁₀ copies/100 ng RNA) and trachea, with dissemination to the kidney and pancreas. Histopathological and FISH analyses localized viral RNA to epithelial lesions, while transcriptomic profiling revealed a robust upregulation of pro-inflammatory cytokines (particularly CXCL8) in the heavily infected intestine. Notably, selection pressure analysis indicated strong purifying selection acting on the feline VP1 gene, with no positively selected sites identified, contrasting with signatures of episodic positive selection observed in human and rodent lineages. This study provides the first definitive evidence that AiV-A can act as a fatal systemic pathogen in a large felid, significantly expanding the known host range of kobuviruses. Our findings underscore the need for vigilant surveillance of kobuviruses in captive wildlife and highlight the potential risk of spillover infections from domestic carnivore reservoirs.

Abstract: Crude glycerin (CG), a coproduct of biodiesel production, is a glucogenic energy source that can replace corn in high-concentrate ruminant diets, but the feedlot phase of inclusion may determine whether it sustains or depresses intake. The aim was to evaluate the effects of replacing of corn with CG (300 g/kg DM) during adaptation and/or finishing on per-formance, feeding behavior, in vitro DM digestibility of diets, liver abscess, rumen epithe-lium and carcass traits in feedlot Nellore. Sixty bulls (300.5 ± 28.5 kg) were fed for 77 days in a randomised complete block design, 2 × 2 factorial (adaptation × finishing). CG during adaptation increased final body weight (p = 0.014), average daily gain (ADG; p = 0.035) and feed efficiency (p = 0.036), without altering dry matter intake (DMI). During finishing, CG reduced DMI by 20% (p = 0.001) and ADG by 11% (p = 0.024) but improved feed effi-ciency (p = 0.045), leaving carcass and meat traits unaffected. These bulls also ate longer at a slower rate, with a lower epithelial mitotic index (p < 0.001), while in vitro DM digestibil-ity of the finishing diet increased (p < 0.001). These findings show that timing governs the response to CG: during adaptation it enhances gain, whereas in finishing it exchanges in-take for efficiency without compromising carcass traits, supporting its use as an energy alternative to corn in Nellore feedlots.

Abstract: Digital twins promise to turn continuous poultry observations into biologically informed decisions about welfare, physiology, behavior, production and product quality. Yet the concept outruns its evidence. This critical narrative review asks when measurements become a credible representation of an embryo, bird, flock or egg, and when that representation improves husbandry. We examine recent studies, welfare assessments and industry evidence through physiological, ethological, welfare and production lenses. Seven programs organize the synthesis: HatchTwin for embryonic development; HenTwin for longitudinal change in laying hens; CluckTwin for contextual acoustic evidence; EggTwin for identity, quality, handling and traceability; FlockTwin Population for collective movement and resource use; BroilerTwin for the distinctive biology of meat chickens; and ChickenTwin for comparison without biological homogenization. Across these programs, observations remain inherently ambiguous. Reduced movement may indicate rest, growth, pain, heat load, fear or restricted opportunity; sound, surface temperature, clustering and production shifts are context dependent. Detection is therefore an entry point, not validation. A decision-worthy twin must establish independent biological credibility, operate prospectively, arrive within an actionable window, fit farm practice and demonstrate benefit against current practice. Welfare cannot be inferred from productivity or activity alone, flock averages may conceal vulnerable birds, and egg identity does not establish hen-level provenance. We propose silent-mode evaluation followed by cluster-randomized or justified stepped implementation, measuring welfare, production, labor, economics, governance and unintended harm. The opportunity is considerable, but integrated commercial evidence remains absent. Poultry digital twins will earn authority only by enabling earlier care, fewer preventable harms and more resilient farms.

Abstract: To investigate the potential contribution of leukocyte morphology to animal welfare assessment, this study evaluated leukocyte profiles in beef cattle raised under intensive and extensive production systems. A total of 664 blood samples were collected at the end of the production cycle from commercial farms in Mato Grosso do Sul, Brazil. Welfare assessments included qualitative behavioral assessment, health indicators, hematocrit, total and differential leukocyte counts, neutrophil-to-lymphocyte (N/L) ratio, and leukocyte morphology using an image-supported scoring system. Neutrophils from intensively raised cattle exhibited a significantly higher frequency of morphological alterations (27.0% vs. 11,4%; p< 0.001), including toxic changes and immature forms, as well as a higher prevalence of atypical lymphocytes (22.0% vs. 9.6%; p < 0.001). Hematocrit values, total leukocyte counts, neutrophil counts, and N:L ratios were significantly higher in intensively managed cattle, whereas lymphocyte counts were higher in cattle raised under extensive conditions (p < 0.05). Qualitative behavioral assessment indicated greater variability in behavioral expression among cattle from intensive farms, while cattle from extensive systems indicated a predominance of descriptors associated with positive affective expression. Health alterations, including nasal discharge, coughing, and swelling, were recorded exclusively in intensive systems. These findings demonstrate that leukocyte morphology differs between cattle raised under contrasting production conditions and suggest that leukocyte morphological assessment may provide a useful complementary animal-based indicator within multidimensional welfare assessment frameworks.

Abstract: Maintaining appropriate nest temperatures during the first weeks of life is essential because neonatal puppies have limited thermoregulatory capacity. Commonly used warming methods in breeding and veterinary settings, including infrared heat lamps and electric heating pads, may produce uneven heating, unstable temperature regulation, or temperatures that are difficult to measure accurately. This study evaluated the performance and temperature measurement characteristics of commonly used neonatal puppy warming methods and compared them with a thermostatically controlled water warming system. Temperature stability, surface uniformity, and differences among temperature measurement methods were evaluated under standardized environmental conditions using Type K thermocouples, handheld infrared thermometers, digital surface thermometers, and infrared thermal imaging. Infrared-heated surfaces demonstrated substantial variation in measured temperatures depending on the measurement method and surface characteristics. Electric heating pads exhibited significantly higher surface temperatures (p < 0.05), localized hot spots, and greater temperature fluctuations than desired for neonatal thermal support. In contrast, the recirculating water warming system demonstrated greater temperature stability and more uniform heating than the other methods evaluated, with adjacent fleece temperatures maintained within the target neonatal nest temperature range.

Abstract: Pseudopus apodus is an anguimorph lizard belonging to the order Squamata. Anatomical information on this species remains limited, particularly regarding soft tissues, and has primarily focused on the axial skeleton of both living and fossil specimens. Recently, the anatomy of its coelomic cavity has been described using dissection and multidetector computed tomography (CT), and its brain has been characterized neuroanatomically by combining ultra-high-resolution magnetic resonance imaging (MRI) with histological analysis using immunofluorescence. In the present study, four specimens (one female and three males) were examined. One male and the female were scanned using a low-field MRI system (0.23 T), whereas all three males were scanned using a high-field MRI system (1.5 T). Both MRI systems enabled the identification of a wide range of hard and soft anatomical structures. Only a few small structures could not be consistently identified with the low-field system, including the thyroid gland, spleen, pancreas, testes, and hemipenes. Despite the lower field strength, small ovarian follicles and the optic nerves were clearly visualized with the low-field MRI system. This study provides the first whole-body MRI anatomical reference for Pseudopus apodus, complements previous CT-based anatomical studies, and offers practical information for the interpretation of MRI examinations in reptiles.

Abstract: Chronic cold stress impairs hepatic metabolism, antioxidant balance and fetal development of Mongolian sheep in northern pastoral zones, yet systematic research on nutritional mitigation remains limited. N-carbamylglutamate (NCG) boosts endogenous arginine synthesis, but its hepatic regulatory mechanisms against cold stress in pregnant ewes and fetuses remain unclear. This study explored NCG’s protective effects via integrated liver transcriptome and metabolome analysis. Twenty-four late-gestation ewes were divided into warm control, cold stress, and cold stress + daily NCG supplementation groups. Hepatic mRNA, lncRNA, circRNA, miRNA sequencing, untargeted LC-MS metabolomics, multi-omics conjoint analysis and qRT-PCR verification were conducted on ewe and fetuses liver samples. The results showed that, cold stress disturbed mTOR, PI3K/AKT, amino acid and energy metabolic pathways, triggering massive differential RNA and metabolite changes. NCG supplementation reversed cold-induced transcriptional and metabolic disorders, restoring glutathione and cysteine-methionine metabolism. Core hub genes AK4, AHCY and RRM2 linking transcriptomic and metabolic shifts were validated by qPCR, with divergent hepatic NCG responses observed between ewes and fetuses. Maternal NCG alleviates cold-caused liver oxidative damage, remodels energy and amino acid metabolism via mTOR and redox pathways, and confers transgenerational protection to fetuses through the maternal-placental-fetal axis. These findings elucidate NCG’s anti-cold-stress molecular mechanism and provide a basis for nutritional intervention for cold-region sheep farming.

Abstract: Antimicrobial resistance surveillance in companion animals requires phenotypic data that preserve bacterial assignment, antimicrobial agent, measured inhibition zone, interpretive category, and host linkage at the isolate level. This study reconstructed and analysed the cultivable oral bacterial fraction recovered from 100 dogs attending urban veterinary clinics in Loja, Ecuador, during April and May 2026. The archived analytical file contained 139 isolates linked to 82 represented dog identifiers. Conventional culture and biochemical testing produced presumptive phenotypic assignments comprising 48 Staphylococcus aureus, 38 Pseudomonas species, 29 Klebsiella species, 11 Enterobacter species, nine Salmonella species, and four Escherichia coli isolates. Antimicrobial susceptibility was evaluated by taxon and agent using the effective tested denominator rather than a common Gram group denominator. The Gram positive panel contained penicillin, oxacillin, ampicillin with sulbactam, and cefoxitin. The Gram negative panel contained ampicillin with sulbactam, ceftriaxone, streptomycin, trimethoprim with sulfamethoxazole, and tetracycline, although evaluability varied among taxon and agent combinations. Presumptive S. aureus showed penicillin resistance in 23 of 48 isolates, while all isolates were recorded as susceptible to oxacillin, cefoxitin, and ampicillin with sulbactam. Enterobacter displayed the broadest accumulation, including resistance proportions of 72.7 percent to tetracycline and 63.6 percent to ampicillin with sulbactam. Among Gram negative isolates, 76 of 91 were resistant to at least one represented class and 40 of 91 to at least two classes after audit. Multidrug resistance was estimable only when at least three broad classes had been tested and was identified in 13 of 61 evaluable Gram negative isolates. A generalized estimating equation model with dog identifier as the clustering unit showed an exploratory association between Enterobacter assignment and resistance to at least two classes relative to Pseudomonas, with an odds ratio of 13.32, a 95 percent confidence interval of 1.32 to 134.56, and a p value of 0.028. Exclusion of records with discordant host descriptors attenuated this estimate to an odds ratio of 8.41 and a p value of 0.052. The study provides a taxon resolved phenotypic baseline and a reproducible framework for companion animal antimicrobial resistance surveillance in settings where culture based diagnostics remain central.

Abstract:

This study aimed to characterize the age dependence of time to union and healing morphology in longitudinally displaced distal radius and ulna fractures in small dogs. Medical records and serial radiographs of 107 small dogs treated with an anatomically molded cast (AMC) between 2019 and 2025 were retrospectively analyzed. Dogs were classified into four age groups (<6 months, 6 to <12 months, 1 to <2 years, and ≥2 years), and time to radiographic union, relative bone diameter expansion, and the interfragmentary distance reduction rate (IDR) were evaluated. Radiographic union was achieved in all cases. Median times to union were 40.0, 52.0, 64.0, and 81.0 days in ascending order of age, with a significant difference among age groups (P < 0.001). After adjustment for age group in multivariable analysis, each 1-kg decrease in body weight was associated with a 6.2% longer time to radiographic union (P = 0.014). Relative bone diameter expansion was greatest and IDR was lowest in dogs aged <6 months (both P < 0.001). Thus, both time to union and healing morphology under AMC treatment were strongly associated with developmental stage from growth to skeletal maturity. Healing morphology represented a continuous spectrum from envelopment-dominant healing, characterized by abundant callus formation during growth, to convergence-dominant healing, characterized by remodeling of the fracture ends and fragment convergence with skeletal maturation. These findings provide practical clinical guidance for age-specific prognostication, owner communication, and treatment planning.