American journal of veterinary research最新文献

Objective: To evaluate sedation in horses following pharmacopuncture with dexmedetomidine at acupoint Governing Vessel 24 (GV-24) compared to aquapuncture at GV-24 or an equivalent dose of dexmedetomidine administered via IV or SC routes.

Methods: 10 adult mares received 4 treatments in a blinded, randomized, crossover design: (1) dexmedetomidine administered at GV-24 (DexmedGV24; 1 μg/kg); (2) saline administered at GV-24 (SalineGV24; 1.5 mL); (3) dexmedetomidine administered SC on the lateral neck (DexmedSC; 1 μg/kg); or (4) dexmedetomidine administered IV (DexmedIV; 1 μg/kg). Sedation scores (facial sedation scale [FaceSed] and equine sedation scale [EquiSed]), head height above ground, pulse rate, and respiratory rate were collected at baseline and 5, 15, 30, 45, 60, and 90 minutes after treatment (T5, T15, T30, T45, T60, and T90). Head height above ground, FaceSed, and EquiSed were compared with a pairwise Wilcoxon signed rank test.

Results: There were no significant differences in sedation scores between treatment groups at any time points. When compared to baseline, the FaceSed scores were significantly higher at all time points in DexmedGV24 and SalineGV24; at T15, T30, T60, and T90 in DexmedSC; and at T5, T15, T30, T45, and T60 in DexmedIV. The EquiSed scores were significantly higher at T5 and T60 in DexmedGV24; at T30 and T45 in SalineGV24; at T45, T60, and T90 in DexmedSC; and at T5, T15, T30, T45, and T60 in DexmedIV. Head height was significantly lowered at T60 in DexmedGV24 and at T5, T30, T45, and T60 in DexmedIV.

Conclusions: Pharmacopuncture with dexmedetomidine at GV-24 provided sedation with no significant difference compared to SC administration, IV administration, or aquapuncture at GV-24.

Clinical relevance: Pharmacopuncture with dexmedetomidine or saline aquapuncture at GV-24 is an alternative route for sedation in horses.

Objective: To determine if a single training session suffices for teaching novices construction of the 4S-modified Roeder (4SModR) slip knot.

Methods: From June through August 2022, Doctor of Veterinary Medicine candidates received written and video-based tutorials prior to a single in-person training session performed by a Doctor of Veterinary Medicine candidate with extensive training but without laparoscopic surgical experience (intermediate). Knots were tied before and after a single training session using a laparoscopic video trainer, and instruction proceeded until each participant correctly tied 4 consecutive knots. Novice and intermediate tied knots underwent biomechanical testing. Training time and common errors were documented. The 2 most common knot-tying errors were reproduced by the intermediate tyer and biomechanically tested.

Results: Post-training novice-tied 4SModR knots were significantly stronger than the pretraining knots in both loop holding strength and load at failure. The failure load, but not the loop holding strength, of post-training knots was lower than the intermediate tyer's knot constructs. The inability to differentiate the loop end and the post end resulted in significantly weaker knots, with 9 of 12 knots with that error recreated failing at less than 7 N before load.

Conclusions: A short training session results in weaker knots when compared to knots tied by a more experienced tyer.

Clinical relevance: Substantial training time is required to learn and produce a strong 4SModR knot. Adequate time to learn, practice, and perform these knots should be allocated for surgery trainees.

Objective: To identify potential long-term sequelae associated with crotalid (pit viper) envenomation in dogs and cats.

Methods: A retrospective review of medical records identified dogs and cats that survived to hospital discharge following pit viper envenomation from January 1, 2018, through July 31, 2024. Pet owners were solicited via email to participate in an online survey from July 17, 2024, through August 31, 2024. The survey responses were analyzed to describe outcomes and to assess potential associations between the number of vials of antivenom administered, modified snake bite severity score, medical and behavioral sequelae, and time to full recovery.

Results: 51 of 241 surveys (21%) were returned. Forty-seven dogs and 4 cats were enrolled in the study. Forty patients (78%) returned to normal within 5 days of discharge, whereas it took 3 dogs (6%) 6 to 9 weeks to fully recover. Seven patients (13.7%) were suspected of developing behavioral changes after envenomation. The Modified Snakebite Severity Score at admission correlated with the number of antivenom vials administered (ρ = 0.412) and the number of days to return to normal behavior (ρ = 0.455); however, the number of vials of antivenom administered was not significantly associated with recovery duration.

Conclusions: Long-term sequelae were uncommon in dogs and cats after pit viper envenomation.

Clinical relevance: Pet owners should be informed of potential transient lethargy (< 5 days) and instructed to seek veterinary care if their pet's lethargy persists for longer.

Objective: To describe the oral microbiota in bearded dragons (Pogona vitticeps) with or without dental disease and evaluate the impact of fruit consumption.

Methods: 42 total client-owned bearded dragons were categorized into groups: healthy (absent or mild dental disease [n = 21]) and diseased (moderate to severe dental disease [21]). An additional analysis compared fruit-eating (n = 17) and non-fruit-eating bearded dragons (25). Following dentition assessment, all oral quadrants were sampled at 1 time point for DNA extraction via next-generation sequencing targeting bacterial 16S rRNA and fungal internal transcribed spacer 2 regions. The α- and β-diversity, taxonomic abundance, core microbiota analysis, and linear discriminant effect size analyses were compared between groups.

Results: The oral microbiota comprised 1,317 and 163 fungal species. Although there were no significant differences in bacterial or fungal α-diversity between healthy and diseased groups, bacterial β-diversity differed significantly. Certain taxa were more abundant in the dental disease group, including Pseudomonas aeruginosa, Devriesea agamarum, Serratia marcescens, and the Aspergillus genus. Additionally, the microbiota of bearded dragons that consumed fruit was significantly altered.

Conclusions: There were distinct organisms in the oral microbiota attributed to dental disease, with specific organisms more abundant in diseased individuals, suggesting an association with disease. Bearded dragons fed fruit had more abundant microbial species, indicating fruit consumption may promote oral microbial overgrowth.

Clinical relevance: Both differences in the oral microbiota and increased prevalence of specific species associated with dental health status and diet should be considered when making husbandry and therapeutic decisions for bearded dragons.

Objective: To examine the concentration of platelet-derived extracellular vesicles (PEVs) and procoagulant PEVs in a population of dogs with different types of neoplasia and varying stages of disease.

Methods: In this observational cross-sectional study, platelets and PEVs were obtained from dogs with neoplasia. Platelet-derived extracellular vesicle concentrations and expression of phosphatidyl serine (PS) as a marker of procoagulant potential were analyzed by use of flow cytometry.

Results: Samples were obtained from 113 dogs with benign (n = 33) or malignant (80) neoplasia as well as from 15 healthy dogs. The overall PEV concentration did not differ between the groups. The concentration of PS-positive (PS+) PEVs was significantly higher for both benign (median, 4.4 X 103 PEVs/µL; IQR, 2.9 to 7.0) and malignant neoplasia (median, 4.4 X 103 PEVs/µL; IQR, 2.8 to 6.8) compared to the group of healthy dogs (2.1 X 103 PEVs/µL; IQR, 1.4 to 4.6). This was especially the case for dogs with regional metastatic disease, which, on average, had a 5 X 103 PEVs/μL higher PS+ PEV concentration compared to other groups (95% CI, 0.6 X 103 to 8.6 X 103 PEVs). The platelet expression of PS did not differ between the groups.

Conclusions: Dogs with neoplasia had higher concentrations of PS+ PEVs than healthy dogs but not higher overall PEV concentrations.

Clinical relevance: The findings in this study could indicate that the concentration of PS+ PEVs plays a role in both benign and malignant neoplasia, and their relationship with regional metastatic disease needs further evaluation.

Objective: To visualize the endothelial glycocalyx in equine intestinal vessels using electron microscopy and immunohistochemistry and to evaluate the impact of induced endotoxemia on its integrity.

Methods: 6 healthy horses free of gastrointestinal disease were anesthetized with dexmedetomidine, ketamine, and diazepam and mechanically ventilated under isoflurane anesthesia. Jejunal venous tissue samples were collected after perfusion fixation with lanthanum nitrate before and 120 minutes after endotoxemia induced by IV administration of 30 ng·kg-1 Escherichia coli lipopolysaccharide. For transmission electron microscopy, samples were fixed in lanthanum nitrate solution and embedded in epoxide resin. Additional samples were fixed in formaldehyde, embedded in paraffin, and sectioned for indirect immunohistochemistry to assess heparan sulfate, syndecan-1, catalase, and superoxide dismutase-2 expression.

Results: The endothelial glycocalyx ultrastructure was successfully visualized in 3 of 6 horses. Morphological variations, particularly in glycocalyx thickness (up to 2.5 µm), were observed. Endotoxemia-related alterations indicating structural disruptions were evident in these horses. Immunohistochemical staining for syndecan-1 and superoxide dismutase-2 showed no assessable immunoreactivity, whereas heparan sulfate and catalase immunolabelling were detected on the endothelium.

Conclusions: The endothelial glycocalyx of intestinal vessels was visualized for the first time in horses. Among the tested antibodies, only those against heparan sulfate and catalase demonstrated endothelial reactivity, confirming their presence as components of the equine glycocalyx. Lipopolysaccharides may cause structural disintegrity and loss of glycocalyx.

Clinical relevance: Visualization of the equine endothelial glycocalyx enhances understanding of vascular pathophysiology in endotoxemic horses. Investigation of the glycocalyx remains technically demanding.

Objective: To identify optimal cadaveric preparation methods for sentinel lymph node mapping in experimental procedures.

Methods: Apparently healthy canine cadavers were obtained from local shelters following humane euthanasia unrelated to the study. This experimental study was conducted from October 2023 through July 2024 at the University of Florida College of Veterinary Medicine. Cadaveric preparations were categorized as follows: fresh, refrigerated, frozen-thawed, and heated (refrigerated and frozen specimens). Indocyanine green (ICG) was injected into established lymphosomes, targeting the superficial cervical, axillary, superficial inguinal, and popliteal lymph nodes. Lymphatic tracts were identified using near-infrared fluorescence. Time to lymph node uptake or cessation of tract progression and tract distance (centimeters) was recorded to calculate velocity (cm/s) when applicable. Lymph nodes were then extirpated to assess fluorescence.

Results: 9 adult mixed-breed canine cadavers were used, with a lymph node distribution of 11 fresh, 30 refrigerated, 3 refrigerated-heated, 17 frozen-thawed, and 3 frozen-thawed-heated specimens. Fresh and refrigerated cadavers demonstrated consistent and reliable uptake of ICG into the lymphatic tracts and the respective lymph nodes. Frozen-thawed cadavers demonstrated consistent lymphatic tract uptake but inconsistent uptake to the respective lymph nodes. Heating did not improve lymph node fluorescence in refrigerated or frozen-thawed cadavers.

Conclusions: Fresh and refrigerated cadaveric preparations are ideal for sentinel lymph node mapping with ICG. Heating of the cadavers did not improve lymph node fluorescence.

Clinical relevance: When fresh canine cadavers are not accessible, refrigerated cadavers can be reliably used for experimental peripheral sentinel lymph node mapping.

Objective: To characterize age-related trajectories of the relative concentrations of anti-virulence-associated protein A (VapA) immunoglobulin (Ig)-G1, IgG3/5, IgG4/7, and IgA in serum and bronchoalveolar lavage fluid (BALF) as indicators of systemic and intrapulmonary immune responses in foals naturally exposed to Rhodococcus equi.

Methods: Blood and BALF samples were collected at ages 4, 14, 28, and 56 days from healthy Quarter Horse foals (n = 19) naturally exposed to R equi. Samples were tested via ELISA for relative concentration of IgG1, IgG3/5, IgG4/7, and IgA recognizing the VapA of R equi. Data were analyzed using linear mixed-effects modeling to compare VapA ELISA results by age for IgG subisotypes and IgA.

Results: Serum relative concentrations of VapA-specific IgG1, IgG3/5, IgG4/7, and IgA of 19 foals did not differ significantly during the first 28 days of age but increased nearly 10-fold by age 56 days. Similarly, BALF relative concentrations of VapA-specific IgG1, IgG3/5, and IgG4/7 in these foals did not differ significantly during the first 28 days of age but increased by about 10-fold by age 56 days. In contrast, BALF relative concentrations of VapA-specific IgA increased progressively with age.

Conclusions: Natural exposure results in progressive increase in BALF concentration of IgA but not IgGs, indicating intrapulmonary IgA response to virulent R equi.

Clinical relevance: Foals do not mount strong antibody responses to R equi when they are most vulnerable to infection. Further investigation is warranted to determine if increasing intrapulmonary antirhodococcal IgA is a correlate of protective immunity or merely a marker of exposure.

Objective: To evaluate the dose-dependent effects of single dosing of dapagliflozin on pharmacodynamics, diuresis, and ketogenesis in dogs.

Methods: This study included 5 healthy Beagles. A single dose of dapagliflozin (0.1, 0.3, or 1.0 mg/kg) or placebo was orally administered (randomized 14-day intervals) to each dog. Blood and urine samples were collected prior to administration and at 1, 2, 3, 4, 5, 6, 9, 12, and 24 hours after administration. A urinary catheter was placed from 0 to 6 hours after administration to monitor urine volume and collect samples; thereafter, urine was collected using a metabolic cage. Plasma ketone bodies, sodium, potassium, chloride, and glucose concentrations were measured. Urinary sodium, potassium, chloride, glucose, and urine volume were measured and compared among the treatment groups.

Results: 24-hour urinary glucose excretion was significantly increased in the 0.3-mg/kg group compared with the 0.1-mg/kg group. However, no significant difference in 24-hour urinary glucose excretion was observed between the 0.3-and 1.0-mg/kg groups. Plasma ketone body concentration was significantly higher in the 1.0-mg/kg group compared with the placebo group at 4, 5, 6, 12, and 24 hours after administration. The 6-hour urine volume (mL/kg) was significantly higher in the 1.0-mg/kg group compared with the placebo group.

Conclusions: In healthy dogs, a single oral administration of dapagliflozin at 1.0 mg/kg induced both ketogenic and diuretic effects.

Clinical relevance: This study provides preliminary insight into dapagliflozin's effects in healthy dogs; further studies are needed to assess relevance in dogs with heart failure.