Objective:To compare itraconazole therapeutic drug monitoring (TDM) results by culture-based bioassay versus liquid chromatography-mass spectrometry (LC-MS) in dogs with blastomycosis and determine how the choice of assay might influence dosage adjustments. Methods:This was a retrospective study. Ninety-seven samples from 14 client-owned dogs with blastomycosis were collected from October 2023 through May 2025 and analyzed by bioassay and 3 LC-MS-derived variables: itraconazole alone (ITZ), the hydroxyitraconazole metabolite, and the sum of itraconazole and hydroxyitraconazole. Linear mixed models were used to assess the relationship between dosage and itraconazole concentration by bioassay and LC-MS and between bioassay and the LC-MS variables. A clinical concordance grid was used to assess agreement between bioassay and ITZ by LC-MS regarding dosage-adjustment decisions. Results:There was no significant association between itraconazole dosage and serum concentration. There was a significant relationship between concentration by bioassay versus LC-MS (P < .01). The association was weak for ITZ (r2 = 0.40) but was moderate for the hydroxyitraconazole metabolite (r2 = 0.48) and the sum of itraconazole and hydroxyitraconazole (r2 = 0.48). Of 97 samples, 62 (64%) demonstrated agreement in dosage adjustment, and 35 (36%) did not. Conclusions:Dosage of itraconazole does not reliably predict serum itraconazole concentration, requiring TDM for effective dosage-adjustment decisions. Bioassay and LC-MS are not interchangeable assays for itraconazole TDM in dogs. Clinical Relevance:TDM should be considered during long-term itraconazole therapy to optimize dose. A single assay method (bioassay or LC-MS) should be used consistently throughout the entire course of antifungal therapy.
Objective:To investigate the nasal carriage of Cryptococcus-related and other opportunistic yeasts in dogs, molecularly characterize the recovered isolates, and evaluate the epidemiological characteristics of Naganishia albida carriage. Methods:Nasal swab samples were collected from July through December 2023 from 100 dogs receiving boarding or hospitalization services at private veterinary clinics and animal hospitals in 4 provinces of Türkiye. Yeast isolates were identified using phenotypic methods, internal transcribed spacer 2 sequencing, and matrix-assisted laser desorption ionization-time-of-flight mass spectrometry. The 1-year clinical history of dogs carrying N albida was retrospectively reviewed. Results:A total of 79 isolates representing 31 yeast species were identified from 59 dogs. Cryptococcus neoformans/gattii species complex organisms were not isolated from any dog. Naganishia albida and Papiliotrema laurentii were isolated from 12% and 1% of dogs, respectively. Naganishia albida carriage was detected in both clinically healthy and clinically affected dogs, with higher frequencies observed among dogs presenting with respiratory, dermatological, or systemic clinical findings. However, no significant associations were identified between N albida carriage and the evaluated epidemiological variables. Conclusions:Dogs may harbor diverse opportunistic yeasts, including Cryptococcus-related yeasts, within the nasal cavity. Clinical Relevance:Opportunistic yeasts can colonize the nasal cavities of both clinically healthy and clinically affected dogs. These findings provide baseline epidemiological data for interpreting fungal culture results and contribute to a better understanding of opportunistic fungal carriage in companion animals.
Objective:To characterize CT perfusion (CTP) in canine massive hepatocellular carcinoma (HCC) and explore associations with descriptive histomorphologic differentiation categories. Methods:This retrospective study included 20 client-owned dogs with surgically excised, histopathologically confirmed HCC of the massive gross phenotype and interpretable preoperative CTP datasets. Hepatic arterial flow (HAF), portal venous flow (PVF), and hepatic perfusion index (HPI) were calculated with a dual-input maximum-slope method. Freehand tumor regions of interest were drawn as large as possible along tumor margins while excluding visible vessels and necrotic or cystic regions. The CTP metrics were compared between tumor and nontumorous liver and among differentiation groups. Results:Tumors had lower PVF than nontumorous liver (23.40 vs 127.15 mL/min/100 mL; P < .001) and higher HPI (65.81% vs 29.66%; P < .001), whereas HAF did not differ (52.98 vs 50.29 mL/min/100 mL; P = .154). Among differentiation groups, HAF differed (global P = .011; well > moderate; adjusted P = .042), PVF differed (global P = .025; poor < well; adjusted P = .031), and HPI did not differ (global P = .664). Conclusions:Canine HCC showed relative arterial dominance on CTP driven mainly by reduced PVF. Although HAF and PVF differed among differentiation categories, these findings should be interpreted cautiously because only 3 tumors were poorly differentiated. Clinical Relevance:CTP may provide quantitative arterial and portal perfusion information but should not replace morphologic imaging, surgical assessment, or other established diagnostic and prognostic approaches; it cannot define histologic type or differentiation or predict metastasis, resectability, or prognosis.
Objective:To establish reference values for intact parathyroid hormone (PTH), ionized calcium (iCa) using both whole blood and serum samples, and serum total calcium in domestic rabbits. Methods:Blood samples were collected at a private veterinary hospital from clinically healthy client-owned, mixed-breed, mixed-sex, adult (1 to 7 years of age) rabbits using manual restraint over a 5-month period. Complete blood count, serum biochemical analysis, and i-STAT were performed for each sample. Serum iCa and intact PTH concentrations were analyzed by the Michigan State University Veterinary Diagnostic Laboratory. Reference value intervals and descriptive statistics for intact PTH, iCa, and serum calcium were established per the guidelines of the American Society for Veterinary Clinical Pathology. Results:Reference intervals for PTH (0.50 to 5.90 pmol/L), serum total calcium (12.60 to 16.50 mg/dL), iCa using whole blood on i-STAT (1.35 to 1.82 mmol/L), and iCa using serum on a benchtop analyzer (1.53 to 1.84 mmol/L) were established from a population of 50 rabbits. In this population of rabbits, there was a statistically significant difference between the whole blood iCa (1.64 ± 0.10 mmol/L; mean ± SD) and the serum iCa (1.70 ± 0.07 mmol/L); however, the difference is likely clinically insignificant. Conclusions:This is the first study to establish reference intervals for intact PTH via chemiluminescent analysis in the domestic rabbit. Clinical Relevance:Determining inappropriate increases or decreases in PTH and calcium is crucial for antemortem diagnosis and treatment of primary and secondary disorders of calcium.
Objective:To adapt and partially validate the accuracy and precision of serum exchangeable copper and 3-kDa ultrafiltered urinary copper concentrations as an analytical prerequisite to investigate the clinical utility of relative exchangeable copper and urinary small copper carrier-to-creatinine ratio as noninvasive biomarkers in dogs with copper-associated hepatitis. Methods:Serum exchangeable copper and 3-kDa ultrafiltered urinary copper concentrations of surplus samples of dogs submitted for diagnostic purposes from October 2023 through March 2024 were measured by adapting a previously described ultracentrifugation method. Copper concentrations were quantified using inductively coupled plasma mass spectrometry. The optimal relative centrifugal force was selected based on minimizing the variability among replicates. Analytical performance was evaluated through spike recovery and intra- and interassay repeatability. Results:Optimal parameters were identified as 5 g/L EDTA and 5,000 X g for serum exchangeable copper and 4,000 X g for 3-kDa ultrafiltered urinary copper. Spike recovery ranged from 97.9% to 108.5% for serum exchangeable copper and from 96.7% to 120% for ultrafiltered urinary copper. The median intra- and interassay coefficients of variation were 8.5% and 10.8% for exchangeable copper and 2.6% and 5.6% for ultrafiltered urinary copper, respectively. Conclusions:Ultrafiltration-based methods for measuring serum exchangeable copper and 3-kDa ultrafiltered urinary copper concentrations were successfully adapted for dogs, with spike recovery and intra- and interassay coefficients of variation within predefined acceptance criteria. Clinical Relevance:The results provide the analytical foundation for future investigation of the diagnostic utility of relative exchangeable copper and urinary small copper carrier protein as noninvasive biomarkers for copper-associated hepatitis in dogs.
Objective:To evaluate natural, environmentally safe alternatives for controlling hard ticks in response to emerging resistance against commonly used acaricides. Methods:Punica granatum peel ethanolic extract (PPE) was prepared and then chemically characterized using liquid chromatography-electrospray ionization-tandem mass spectrometry. The adult immersion test was used to evaluate the in vitro anti-tick activity of PPE at the concentrations of 12.5, 25, 50, 100, and 200 mg/mL. The effect of PPE on tick counts and antioxidant activity in artificially infested dogs was assessed for 7 days after application. Results:Chromatographic analysis detected 8 O-glycosylated flavonoids as well as catechin, apigenin, luteolin, and procyanidin. In vitro, immersing adult ticks in 35 mg/mL PPE for 5 min resulted in 50% mortality after 6 hours (LC50). In the in vivo trial, tick-infested dogs sprayed with PPE (35 mg/mL) had significantly lower tick counts than untreated infested controls on days 2, 4, and 7 after treatment, with the maximum count reduction on day 7 (4.67 ± 1.53 in treated dogs vs 81.7 ± 5.0 in controls). In vivo results showed that PPE treatment improved antioxidant activity in tick-infested dogs, increasing glutathione reductase, glutathione peroxidase, and catalase levels while decreasing malondialdehyde. Conclusions:In vivo results showed that PPE treatment improved antioxidant activity in tick-infested dogs, increasing glutathione reductase, glutathione peroxidase, and catalase levels while decreasing malondialdehyde. Clinical Relevance:This study is the first to show the acaricidal activity of PPE against tick species. The results suggest the potential of this botanical byproduct as an alternative to chemical acaricides for tick control.
Objective:To identify if rabbit IV catheter placement (ICP) in the marginal ear vein was readily achievable for veterinary students and whether student confidence improved with ICP experience. We hypothesized that students would achieve successful ICP placement on their first attempt and that student confidence would increase after ICP. Methods:Final-year undergraduate veterinary students on clinical rotations at the University of Edinburgh Hospital for Small Animals participated over a 1-year period. The prospective observational study involved completion of an anonymized questionnaire with 2 parts, completed before ICP and after ICP. The time taken for successful placement and the number of attempts were recorded. Results:70 students participated in this study. Intravenous catheter placement was successful on the first attempt in 78.5% of students; the mean time for successful ICP was 4 minutes and 10 seconds. After ICP placement, students had a statistically significant increase in confidence in rabbit ICP, scoring a median of 2.5 points higher in confidence on a 10-point scale. There was no significant correlation between previous ICP experience or preprocedure confidence score and speed of ICP. Conclusions:ICP of the rabbit marginal ear vein is highly achievable for veterinary students, with most students achieving ICP on their first attempt. Following successful ICP, student confidence in this procedure in rabbits increased. Clinical Relevance:Rabbit ICP is readily achievable by veterinary students and should be included as a core clinical skill in undergraduate veterinary education, promoting confidence in students interacting with this species.
Objective:To develop and validate a method to calculate biologic fixation (BFX) acetabular cup open-face plane orientation based on measurements from a lateral radiograph. Methods:The formulas describing the open-face plane orientation were derived using geometric arguments and trigonometry. To assess the method, an in vitro plastic model of a pelvis was implanted with a BFX acetabular cup. A lateral radiograph of the implanted model was obtained and used to calculate the cup open-face plane orientation using the derived method. Direct measurement of the open-face plane orientation was performed, and the calculated values were compared to the directly measured values. The procedure was repeated with the cup in a different orientation for each trial. Results:52 trials were performed. The derived calculation method demonstrated high repeatability and reproducibility, with intra- and interobserver intraclass correlation coefficients > 0.94. The direct measurement method demonstrated high reproducibility, with interobserver intraclass correlation coefficients > 0.98. The mean absolute angular difference between the calculated and directly measured orientation vectors was 2.8 ± 1.3°, with 95% of trials within 4.7°. Conclusions:The open-face plane orientation determined by the derived method agreed closely with the directly measured orientation. Clinical Relevance:Knowledge of the BFX open-face plane orientation can inform decisions regarding cup revision, help identify complications associated with cup malpositioning, and allow the surgeon to improve their cup placement performance.
Objective:To compare the biomechanical stability of 4 fixation techniques for proximal humeral physeal fractures in skeletally immature canines using 3-D-printed models. Methods:This experimental in vitro study was conducted from September 25, 2025, through April 22, 2026. To strictly control biological variability, identical 3-D-printed models of juvenile canine proximal humeral Salter-Harris type 1 fractures (CT-derived from a 6-month-old 26-kg Labrador Retriever) were evaluated across 4 groups: pin and tension band wire (group A), partially threaded cannulated screw (group B), fully threaded headless cannulated screw (FTHCS) alone (group C), and FTHCS with a 1.6-mm Kirschner (K)-wire (group D). Tensile loading was applied at 10 mm/min at 105° to simulate supraspinatus traction. Outcomes included loads at 1- and 2-mm displacements, maximum failure load, and failure modes. Results:Twenty-four models were tested (n = 6/group). Group D exhibited significantly higher resistance at 1-mm (663.95 N) and 2-mm (1,080.33 N) displacements than other groups. At 1-mm displacement, group D outperformed groups C, A, and B (mean differences [MD]: 206.2 N, 380.6 N, and 405.7 N, respectively; P < .0083). Maximum failure load did not differ significantly. Group B failed via localized proximal crushing and subsidence, whereas FTHCS groups (C, D) preserved proximal integrity, failing distally. Conclusions:In this 3-D-printed model, FTHCS combined with a K-wire provided superior resistance to tensile displacement compared with other tested constructs. Clinical Relevance:FTHCS augmented with a K-wire may offer a biomechanically robust alternative mitigating subhead bone collapse, providing sufficient standalone stability for early rehabilitation in immature canines.
Objective:To compare perfusion characteristics in morphologically normal canine brains with dynamic susceptibility contrast (DSC) MRI following manual versus automated contrast medium injection. Methods:Client-owned dogs undergoing routine 3-tesla brain MRI protocol including DSC were prospectively enrolled, randomly allocated to manual or automated contrast medium injection between November 2023 and February 2025. Gadoteric acid (0.1 mmol/kg) was injected at weight-dependent rates: 1 mL/s (1 to 5 kg), 2 mL/s (6 to 15 kg), and 3 mL/s (> 15 kg). Perfusion parameters evaluated included time of contrast medium arrival (T0), time to peak contrast medium enhancement (TTP), mean transit time of contrast medium (MTT), relative cerebral blood flow (relCBF), and relative cerebral blood volume (relCBV) at 3 regions of interest: thalamus, piriform lobe, and semioval center. Mann-Whitney U tests with Holm-Bonferroni correction were used. Rank-biserial correlations were calculated as effect sizes. Results:Dynamic susceptibility contrast studies of 29 dogs with morphologically normal brains were included (16 manual and 13 automated injections). Manual injection showed longer T0, TTP, and MTT in all regions of interest and higher relCBV in the semioval center compared to automated injection. The relCBF was higher in the thalamus and piriform lobe with automated injection. Conclusions:With manual injection, the perfusion curves appeared flatter and wider compared to automated injection, resulting in prolonged T0, TTP, MTT, and reduced relCBF. Clinical Relevance:Automated injection achieves superior reproducibility of DSC curves. However, manual injection is also feasible, but wider DSC curves should be expected, and appropriate reference parameters should be considered when evaluating brain pathology.
Objective:To evaluate the frequency and type of vehicular restraint use in dogs transported to a veterinary teaching hospital and to identify factors associated with restraint use. Methods:This prospective, survey-based study was conducted at a veterinary teaching hospital from May 28 to August 2, 2024. Dog owners presenting their dog for emergency, sick, or wellness visits completed a questionnaire regarding transportation practices, including restraint use, type of restraint, travel duration, anxiety level, and administration of previsit pharmaceuticals. Logistic regression analysis was performed to assess associations between patient and transport variables and restraint use. Results:A total of 195 of 533 (36.6%) dogs were transported using a restraint system, whereas 338 of 533 (63.4%) were unrestrained. The most common restraint type was a seat belt-based device. Each 1-kg increase in body weight was associated with a 3.3% decrease in the odds of restraint use (OR, 0.97; 95% CI, 0.95 to 0.98). Administration of previsit pharmaceuticals (OR, 1.8; 95% CI, 1.02 to 3.01) and having pet insurance (OR, 1.5; 95% CI, 1.01 to 2.34) were associated with restraint use. Age, reason for visit, travel duration, anxiety level, and mode of transportation were not associated with restraint use. Conclusions:Most dogs in this population traveled unrestrained during vehicular transport. Restraint use was not associated with visit type, travel duration, anxiety level, or transportation mode. Clinical Relevance:Increased veterinary client education may improve safe transport practices and reduce the risk of injury during vehicular travel.
Objective:Pituitary pars intermedia dysfunction (PPID) is a prevalent endocrine disease in older horses sharing pathogenetic features with Parkinson disease, including dopaminergic neurodegeneration and α-synuclein aggregation. This study was conducted to determine whether horses with PPID exhibit changes in short-chain fatty acid (SCFA) profiles as described in Parkinson disease, providing further evidence for involvement of a microbiota-gut-brain axis in the pathogenesis of PPID. Methods:Prospective case-control study including 22 horses > 12 years of age. Diagnosis of PPID was based on clinical signs and results of a thyrotropin-releasing hormone stimulation test. Fecal samples were collected every 2 months for 12 months, and SCFA concentrations (butyrate, propionate, acetate, valerate, isobutyrate, and isovalerate) were quantified using liquid chromatography-mass spectrometry. Data were normalized to sample total protein concentration and analyzed using a linear mixed-effects model with Šídák multiple comparison tests. Results:9 horses were classified as PPID and 13 as controls. Month had a significant effect on concentrations of all measured SCFA across both groups. The PPID status was associated with significantly altered patterns in concentrations of butyrate (average estimate of difference: 0.30 μM/mg; 95% CI, 0.02 to 0.58), valerate (0.04 μM/mg; 95% CI, 0.01 to 0.08), and isobutyrate (0.10 μM/mg; 95% CI, 0.04 to 0.17). Conclusions:Horses exhibit marked seasonal variations in fecal SCFA concentrations, and PPID is associated with selective alterations in fecal SCFA profiles. Clinical Relevance:Altered fecal SCFA profiles in horses with PPID expand our understanding of metabolic changes associated with this condition and warrant further investigation into the relationship between microbial metabolism and the microbiota-gut-brain axis in PPID.
Objective:To assess longitudinal stability of targeted quantitative PCR (qPCR)-based fecal microbial and metabolomic markers in healthy puppies from 8 weeks to 1 year of age. Methods:This prospective longitudinal cohort study was conducted at the Clinic for Small Animal Internal Medicine, Vetsuisse Faculty, University of Zurich, Switzerland, from August 2023 to January 2025. Clinically healthy client-owned puppies were sampled at 8 to 12 weeks, 16 weeks, 6 months, and 1 year. Eligible dogs had no gastrointestinal signs, no previous systemic antibiotics, and negative parasitology. Primary outcomes were the qPCR-based dysbiosis index, selected qPCR-targeted bacterial taxa, fecal bile acids, long-chain fatty acids, and sterols, quantified by mass spectrometry. Mixed-effects models assessed time point associations. Results:23 dogs contributed 62 fecal samples. Dysbiosis index values and most targeted bacterial taxa remained within reference intervals, with no significant longitudinal changes. Bacteroides spp abundance was lower at 8 to12 weeks than at 6 months (difference, -0.73 logDNA copies/g feces; 95% CI, -1.40 to -0.06; Tukey-adjusted P = .028). Secondary unconjugated bile acids dominated at all ages. The concentration of 12-oxo-lithocholic acid was lower at 16 weeks than at 1 year (ratio, 0.33; 95% CI, 0.14 to 0.79; Tukey-adjusted P = .007) but not after multiple-testing adjustment. Long-chain fatty acid and sterol profiles showed no age-related changes. Conclusions:The qPCR-based dysbiosis index and targeted microbial and metabolomic markers were largely stable from 8 weeks to 1 year, supporting early functional maturation of measured markers. Clinical Relevance:These findings establish age-specific baseline information for fecal bacterial and metabolite markers, supporting interpretation in young dogs with gastrointestinal disease.
Objective:Evaluate multidose bioencapsulated terbinafine for the treatment of Emydomyces testavorans in naturally infected Blanding's turtles (Emydoidea blandingii) and determine if this protocol resulted in therapeutic drug concentrations. Methods:Blanding's turtles housed within a quarantine facility were treated with oral terbinafine (30 mg/kg) bioencapsulated within earthworms delivered every 48 hours for 12 months in this experimental study. For all turtles, plasma terbinafine concentrations were quantified, and turtles were routinely tested for of E testavorans through quantitative PCR of combined oral, cloacal, and carapace/plastron swabs. Results:13 Blanding's turtles were enrolled, and no turtle consistently tested negative via quantitative PCR for E testavorans after 12 months of treatment. The median plasma terbinafine concentrations at months 3 and 6 (trough concentrations) were 18 ng/mL (11 to 78 ng/mL) and 36 ng/mL (10 to 76 ng/mL), respectively. The median plasma terbinafine concentrations at months 9 and 12 (peak concentrations) were 163 ng/mL (61 to 575 ng/mL) and 100 ng/mL (13 to 247 ng/mL), respectively. Plasma terbinafine concentrations inconsistently measured above the MIC for E testavorans. No correlation was observed between plasma terbinafine concentrations and E testavorans target copy number by quantitative PCR. Conclusions:Multdose treatment at 30 mg/kg with orally administered, bioencapsulated terbinafine every 48 hours for 12 months failed to achieve molecular resolution of natural E testavorans infection in Blanding's turtles and failed to consistently achieve appropriate plasma concentrations. Clinical Relevance:Emydomyces testavorans is associated with a challenging disease process and is of increasing concern for the health, welfare, and conservation of chelonian species. Further investigation of alternative dosing regimens and/or the use of oral terbinafine as part of multimodal treatment protocols is warranted.
Objective:To compare CT-derived liver volume and noncontrast attenuation variables between dogs with histopathologic findings compatible with primary hypoplasia of the portal vein (PHPV) and dogs without liver disease. Methods:Medical records were retrospectively reviewed for dogs with abdominal CT and liver histopathology compatible with PHPV. Controls were 121 dogs without liver disease from a published CT reference cohort and were not matched by breed, age, sex, or body weight. Liver volume was evaluated with allometric regression of log-transformed liver volume on log-transformed body weight and group. A body weight-restricted sensitivity analysis was performed. Results:26 dogs with PHPV-compatible histopathology and 121 controls were analyzed. Affected dogs were substantially lighter than controls (median body weight, 2.13 vs 38.0 kg). In the primary allometric model, the adjusted geometric mean ratio for liver volume in affected dogs versus controls was 0.887 (95% CI, 0.751 to 1.047; P = .156). The body weight-restricted sensitivity analysis was similar (0.923; 95% CI, 0.769 to 1.107; P = .377). Noncontrast hepatic attenuation did not differ significantly between groups, and qualitative CT abnormalities were uncommon. Conclusions:After allometric adjustment, CT-derived liver volume was not detectably lower in dogs with PHPV-compatible histopathology. This finding should be interpreted cautiously because groups differed substantially in body weight and closely body weight-matched controls were unavailable. Clinical Relevance:These findings do not support using absence of CT-detectable microhepatia to exclude PHPV. Computed tomography volumetry should be interpreted with body size, vascular imaging, clinical findings, and histopathology, especially when controls are not closely matched by body weight.
Objective:To evaluate oxidative stress biomarkers (malondialdehyde [MDA] and total oxidant status [TOS]), selected nonenzymatic endogenous (glutathione [GSH], albumin, and bilirubin), and, for the first time, exogenous (ascorbic acid, α-tocopherol, β-carotene, and retinol) antioxidants together with hematobiochemical alterations in canine pyometra. Methods:33 bitches were classified into pyometra (n = 17) or control (16) groups based on clinical and hematological evaluations. Ascorbic acid was measured by the phosphotungstate method; GSH, MDA, β-carotene, and retinol spectrophotometrically; α-tocopherol by ELISA; and TOS by a colorimetric assay. Hematobiochemical variables were analyzed using automated analyzers. Results:Bitches with pyometra had higher MDA and TOS than controls (36.30 ± 13.95 µmol/L vs 24.61 ± 4.80 µmol/L and 27.78 ± 15.51 µmol H2O2 Eq/L vs 13.13 ± 1.84 µmol H2O2 Eq/L; Hedges' g = 1.08 and 1.27, respectively). Glutathione tended to increase in pyometra (12.04 ± 10.80 nmol/g Hb vs 6.40 ± 2.97 nmol/g Hb; Hedges' g = 0.68), whereas the other antioxidants were similar between groups. Pyometra was also associated with leukocytosis, neutrophilia, monocytosis, decreased erythrocyte counts and Hct, and increased ALP, ALT, and cholesterol. Conclusions:Canine pyometra is accompanied by systemic oxidative stress and hematobiochemical alterations. However, circulating nonenzymatic antioxidants remained largely unchanged, suggesting complex antioxidant regulation rather than simple depletion. Increased GSH may reflect a thiol-based compensatory response to increased oxidative burden. Clinical Relevance:Nonenzymatic antioxidant regulation in canine pyometra may be more complex than simple depletion. Further studies incorporating disease-severity stratification and tissue-level assessments of both enzymatic and nonenzymatic antioxidants are warranted.
