American journal of veterinary research最新文献

Objective: To compare the immunomodulatory capacities of canine placenta-derived mesenchymal stem cells (PMSCs; MSCs) and adipose-derived MSCs (ADMSCs) as well as the effects of their extracellular vesicles (EVs) on peripheral blood mononuclear cells (PBMCs).

Methods: PMSCs and ADMSCs were isolated and characterized. The PBMCs were cocultured with each isolated MSC. PBMC viability was assessed by trypan blue, and CD4 expression and PBMC proliferation were analyzed by flow cytometry. Inflammatory cytokines in the supernatants were measured using an ELISA. In addition, each type of MSC-derived EV was extracted and incubated with PBMCs. Subsequently, the same analyses used in the MSC experiments were performed. Statistical analyses used SPSS 26 with the significance set at P < .05.

Results: In MSC experiments, PMSC group exhibited the highest CD4 expression, and PBMC proliferation was also lowest in PMSC group. PBMC viability was significantly lower in PMSC group. A comparison of the inflammatory cytokine concentrations showed similar IL-2 and IL-10 levels in the groups, whereas TNF-α was significantly lower in PMSC group. In EV experiments, the PMSC EV had a greater ability to inhibit PBMC proliferation than the ADMSC EV, whereas CD4 expression showed no difference. PBMC viability and TNF-α concentration were lowest in PMSC EV group, whereas IL-2 concentration was lowest in ADMSC EV group.

Conclusions: PMSCs and their EVs have comparable immunomodulatory effects to ADMSCs, with some statistically significant differences.

Clinical relevance: PMSC-derived EVs may represent a potential therapeutic option for immune-mediated conditions.

Objective: To create a labeled dataset and evaluate a convolutional neural network (CNN) for segmentation of fluorine-18 sodium fluoride PET scans of the equine metacarpo- and metatarsophalangeal joint (fetlock), targeting the third metacarpal bone, proximal phalanx, proximal sesamoid bone(s), and soft tissue.

Methods: PET and corresponding CT scans were retrospectively selected from June 2024 through November 2025 using convenience sampling and coregistered to a common reference frame. The coregistered PET-CT scans were manually labeled; the labels were then transferred to PET-only images and used to train a cascade of CNNs with and without data augmentation. Segmentation accuracy was quantified using the Dice coefficient and compared to atlas-based segmentation of the PET-CT scans.

Results: A total of 84 scans were collected from 2 facilities. For the test set (n = 8), the minimum, mean, and maximum Dice coefficients computed for all anatomical areas together were 0.85, 0.88, and 0.92, respectively, exceeding the values for atlas-based segmentation of 0.69, 0.80, and 0.87. Analysis of the Dice coefficient by area showed the best CNN segmentation for the third metacarpal bone (mean Dice coefficient (Dmean) = 0.92) and the worst for the medial proximal sesamoid bone (Dmean = 0.82); corresponding atlas-based values were 0.86 and 0.77.

Conclusions: CNN-based segmentation of fluorine-18 sodium fluoride PET images of the fetlock outperforms an atlas-based method in both speed and accuracy measured by Dice coefficient. This advancement enables new, previously inaccessible strategies for PET image quantification.

Clinical relevance: Accurate and robust segmentation of PET fetlocks enables more accurate analysis and novel insights into lesion characterization.

Objective: To assess the effect of kinesiology taping on stifle joint soft tissue swelling in canines 24 hours after tibial plateau-leveling osteotomy (TPLO). The hypothesis was that dogs with kinesiology tape applied postoperatively would have significantly less swelling within 24 hours of surgery compared to those with no kinesiology tape applied.

Methods: Canine stifles undergoing TPLO from October 2023 through June 2025 were randomized into 2 groups: a treatment group with kinesiology tape applied in a double-lymphatic pattern to the surgical stifle postoperatively and a control group with no tape applied. Girth measurements were obtained with pressure-sensitive measuring tape at 3 locations (lateral fabella of the femur, joint line, and tibial tuberosity) at 5 time points (immediately before surgical preparation, immediately postoperatively, 3 hours postoperatively, 18 hours postoperatively [18H], and 24 hours postoperatively [24H]).

Results: 31 canine stifles were split between the treatment (n = 16) and nontreatment (15) groups. The treatment group had significantly less swelling than the control group at the lateral fabella of the femur location at 18H and 24H and at the tibial tuberosity location at 3 hours postoperatively, 18H, and 24H. The kinesiology tape application was well tolerated with no adverse effects.

Conclusions: Kinesiology tape applied in a double-lymphatic pattern at the surgical stifle immediately after TPLO reduces soft tissue swelling during the early inflammatory period.

Clinical relevance: Kinesiology taping provides a simple, low-cost, noninvasive method to reduce stifle joint soft tissue swelling in the immediate TPLO postoperative period.

Objective: To quantify gastrointestinal motility at 3 anatomic locations of the large colon in healthy horses fed 2 diets.

Methods: 12 American Quarter Horses were enrolled in a prospective crossover study. Horses received either a complete pelleted diet fed at 1.35% body weight (BW) per day or Coastal Bermudagrass hay fed at 2% BW with 0.5% to 0.7% BW of complete pelleted feed. Each diet was fed for 13 days prior to motility assessment. Two ultrasonographers recorded the frequency of contractions at the sternal flexure of the large colon, left ventral colon, and cecum for 4 consecutive, 1-minute periods at 2 hours after the morning and evening feedings. A contraction was defined as movement of the large intestinal wall that exceeded 2 cm. Data were analyzed using the Wilcoxon signed-rank and Kruskal-Wallis tests with Bonferroni correction.

Results: Time of day did not affect the frequency of large colon contractions at any site. At the sternal flexure of the large colon, horses fed the complete pelleted feed exhibited a greater frequency of contractions compared to those receiving hay with supplementation. No significant differences in contraction frequency at the left ventral colon or cecum were observed across diets or time points.

Conclusions: These results suggest that diet may affect the frequency of contractions at specific anatomic locations of the large colon in healthy horses.

Clinical relevance: Diet can affect large colon motility in healthy horses, emphasizing the need for veterinarians to consider dietary factors when assessing gastrointestinal health and function.

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.