OBJECTIVE To compare cardiac output (CO) measured by use of CT coronary angiography and thermodilution (criterion-referenced standard) at various CO values, record adverse effects, and determine the time needed to measure CO. ANIMALS 5 healthy purpose-bred Beagles (2 males and 3 females). PROCEDURES A prospective nonrandomized crossover study was conducted. Dogs were premedicated with butorphanol tartrate (0.2 mg•kg−1, IM). Anesthesia was induced by IV administration of etomidate (1 to 2 mg•kg−1) and midazolam (0.25 mg•kg−1). Orotracheal intubation was performed, and anesthesia was maintained by administration of isoflurane. The CO was determined by use of thermodilution and by use of CT at 3 CO values. Dobutamine was infused at various rates to obtain the 3 CO values. RESULTS 13 values were obtained and analyzed. The mean ± SD difference between methods was 0.09 ± 0.71 L•min−1 (95% confidence interval [CI], 0.52 to −0.34 L•min−1). Only 1 of 13 values was located on the 100% agreement line (ie, 0 line), 7 of 13 values were located within the 95% CI, and 5 of 13 values were outside the 95% CI. CONCLUSIONS AND CLINICAL RELEVANCE For this study, there was poor agreement between the 2 methods. The 95% CI interval was 0.52 to −0.34 L•min−1, and 5 of 13 values were outside the 95% CI. Therefore, results for the CT method appeared to be inappropriate for use in making clinical decisions.

OBJECTIVE To determine effects of oral administration of Yunnan Baiyao on platelet activation, coagulation, and fibrinolysis in healthy horses. ANIMALS 12 healthy adult horses. PROCEDURES In a randomized blinded crossover study that included a 4-week washout period between treatments, horses were orally administered a paste containing Yunnan Baiyao (15 mg/kg) or placebo at 12-hour intervals for 3 days. Blood samples were collected before start of treatment (time 0) and at 24 and 72 hours for a CBC, measurement of fibrinogen concentration, coagulation screening tests, and a panel of assays to assess platelet activation (including ADP- and collagen-induced aggregation and closure times, flow-cytometric variables of platelet-leukocyte aggregates, platelet membrane P-selectin and phosphatidylserine expression, and microparticle release), von Willebrand factor (vWF) concentration, and cofactor activity. In addition, thrombelastography was used to evaluate fibrin formation in tissue factor–activated whole blood and plasma and to assess tissue plasminogen activator–induced plasma fibrinolysis. For each treatment, values obtained before and 72 hours after start of administration were compared by use of Wilcoxon signed rank tests. RESULTS Yunnan Baiyao treatment had no significant effect on any hemostatic variable, compared with results for the placebo treatment. CONCLUSIONS AND CLINICAL RELEVANCE Administration of Yunnan Baiyao at a dosage typically used in clinical practice had no effect on in vitro measures of platelet or vWF function and no enhancement of fibrin-clot formation or stability. Any hemostatic actions of Yunnan Baiyao may require higher dosages or result from cell-surface interactions at sites of vascular and tissue injury not examined in this study.

Visceral adipose tissue (AT) obtained from surgical waste during routine ovariectomies was used as a source for isolating canine mesenchymal stem cells (MSCs). As determined by cytofluorimetry, passage 2 cells expressed MSC markers CD44 and CD90 and were negative for lineage-specific markers CD34 and CD45. The cells differentiated toward osteogenic, adipogenic, and chondrogenic directions. With therapeutic aims, 30 dogs (39 joints) suffering from elbow dysplasia (ED) and osteoarthritis (OA) were intra-articularly transplanted with allogeneic MSCs suspended in 0.5% hyaluronic acid (HA). A highly significant improvement was achieved without any medication as demonstrated by the degree of lameness during the follow-up period of 1 y. Control arthroscopy of 1 transplanted dog indicated that the cartilage had regenerated. Histological analysis of the cartilage biopsy confirmed that the regenerated cartilage was of hyaline type. These results demonstrate that transplantation of allogeneic adipose tissue-derived mesenchymal stem cells (AT-MSCs) is a novel, noninvasive, and highly effective therapeutic tool in treating canine elbow dysplasia.

OBJECTIVE To evaluate biomechanical properties of intact feline mandibles, compared with those for mandibles with an experimentally created osteotomy that was stabilized with 1 of 2 internal fixation configurations. SAMPLE 20 mandibles from 10 adult feline cadavers. PROCEDURES An incomplete block study design was used to assign the mandibles of each cadaver to 2 of 3 groups (locking plate with locking screws [locking construct], locking plate with nonlocking screws [nonlocking construct], or intact). Within each cadaver, mandibles were randomly assigned to the assigned treatments. For mandibles assigned to the locking and nonlocking constructs, a simple transverse osteotomy was created caudal to the mandibular first molar tooth after plate application. All mandibles were loaded in cantilever bending in a single-load-to-failure test while simultaneously recording load and actuator displacement. Mode of failure (bone or plate failure) was recorded, and radiographic evidence of tooth root and mandibular canal damage was evaluated. Mechanical properties were compared among the 3 groups. RESULTS Stiffness, bending moments, and most post-yield energies for mandibles with the locking and nonlocking constructs were significantly lower than those for intact mandibles. Peak bending moment and stiffness for mandibles with the locking construct were significantly greater than those for mandibles with the nonlocking construct. Mode of failure and frequency of screw damage to tooth roots and the mandibular canal did not differ between the locking and nonlocking constructs. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that both fixation constructs were mechanically inferior to intact mandibles. The locking construct was mechanically stronger than the nonlocking construct.

The digital cushion (DC) plays a role in absorbing and dampening forces applied to the foot and therefore supports internal structures such as navicular bone; yet, its architecture is not well-known. The goal of this study was to characterize the microanatomical structure of the DC in horses with clinically sound hooves. Both forefeet from the cadavers of 12 adult Quarter horses were cut and sectioned and samples of the following 4 regions of the DC were obtained: axial proximal (AxProx), axial distal (AxDis), abaxial lateral (AbxLat), and abaxial medial (AbxMed). The samples were processed and stained with hematoxylin and eosin, Masson's trichrome, and Weigert's elastic stains. On each slide, 2 central 3- × 3-mm areas were microscopically assessed and all measurements were done within the 9-mm2 area. The number of detected collagen bundles, nerve fascicles, vessels, and the diameter of wall thickness and lumen of blood vessels were measured. Elastic fiber profiles were categorized based on relative density of elastic fibers detected in the field. The percentage of samples in which chondrocytes and adipose tissues were either present or absent was calculated. Significant structural differences were identified among the 4 regions of the DC. The AxDis region contained more collagen bundles (P < 0.0001) and less elastic fiber profiles than the AxProx region (P < 0.0001). The AxDis also contained more collagen bundles than the AbxMed and AbxLat (P < 0.0001) regions. Our findings provide insight into the structure of the DC of mature Quarter horses. The structural differences in the various regions of the DC are presumably related to the different functional properties of those regions; yet more research is warranted.

OBJECTIVE To evaluate the effect of bilateral ventriculocordectomy via ventral laryngotomy on laryngeal airway resistance (LAR) in canine cadaver larynges. SAMPLE 6 clinically normal canine cadaver larynges. PROCEDURES LAR was determined for each specimen before (baseline) and after bilateral ventriculocordectomy with the epiglottis open and closed. After ventral laryngotomy was performed, the vocal cords were sharply excised, and the incised mucosal edges were apposed with 4-0 glycomer 631 suture in a simple continuous pattern. The thyroid cartilage was apposed with 3-0 polypropylene suture in a simple continuous pattern. RESULTS With the epiglottis closed, baseline median LAR was 27.6 cm H2O/L/s (range, 21.2 to 30.6 cm H2O/L/s), which did not differ significantly from the median LAR after bilateral ventriculocordectomy (24.7 cm H2O/L/s [range, 20.6 to 27.7 cm H2O/L/s]). With the epiglottis open, baseline median LAR was 7.3 cm H2O/L/s (range, 5.4 to 7.8 cm H2O/L/s), which did not differ significantly from the median LAR after bilateral ventriculocordectomy (7.2 cm H2O/L/s [range, 6.6 to 7.6 cm H2O/L/s]). CONCLUSIONS AND CLINICAL RELEVANCE Bilateral ventriculocordectomy did not affect LAR with an open epiglottis in canine cadaver larynges. Therefore, it may not be an effective treatment for laryngeal paralysis. It also did not affect LAR with a closed epiglottis, which may indicate protection against aspiration pneumonia.

OBJECTIVE To investigate the effects of meloxicam administration before long-distance transport on inflammatory mediators and leukocyte function of cattle at feedlot arrival. ANIMALS 60 healthy yearling beef steers. PROCEDURES Single-source steers were assigned to a transported (n = 40) or nontransported (20) group. Then, half of the steers within each group were assigned to receive meloxicam (1 mg/kg, PO) or a lactose placebo (1 bolus/steer, PO). All steers were transported approximately 1,300 km overnight to a feedlot; however, the nontransported group was moved before treatment (meloxicam or placebo) administration and allowed a 17-day acclimation period, whereas the transported group was moved immediately after treatment administration on day −1. Blood samples for measurement of inflammatory mediators and leukocyte function were collected from all steers on days −1, 0, and 3. RESULTS For steers that received meloxicam, mean plasma meloxicam concentration for the transported group was significantly greater than that for the nontransported group on day 0. For steers that received the placebo, mean haptoglobin-matrix metalloproteinase-9 complex for the transported group was significantly greater than that for the nontransported group on day 0. Mean haptoglobin concentration, neutrophil L-selectin intensity, and polymorphonuclear leukocyte count for the transported group were significantly greater than those for the nontransported group. Mean substance P concentration for nontransported steers that received meloxicam was significantly lower than that for the other 3 treatment groups. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated meloxicam administration to healthy steers immediately before long-distance transport did not significantly mitigate the effects of transport-induced stress on leukocyte function or inflammatory markers.

OBJECTIVE To evaluate the correlation between the density of native gastric Helicobacter spp and the presence of gastric lesions in dogs. ANIMALS 80 dogs of various breeds, sexes, and ages. PROCEDURES Gastroscopic and histologic examinations were performed for all dogs. Helicobacter spp were detected by combining evaluation of urease activity and results of bacteriologic culture, microscopic observation, and a 16S rRNA PCR assay. The density of Helicobacter-like organisms was evaluated with light microscopy by use of Warthin-Starry modified stain. Correlations were evaluated by use of the Spearman correlation analysis. RESULTS Gastritis was found in 55 of 80 dogs and classified as mild (n = 31), moderate (16), or severe (8). Of these 55 dogs, only 8 had clinical signs. Histologic examination revealed some degree of lymphocytic-plasmacytic infiltrate, mild eosinophilia, and neutrophilic inflammation in the lamina propria. Seventy-six dogs had positive results for Helicobacter spp. Helicobacter pylori DNA was not detected. Low density and homogeneous distribution of Helicobacter spp were observed in all gastric zones. CONCLUSIONS AND CLINICAL RELEVANCE A significant correlation between density of Helicobacter spp and gastroscopic or histologic lesions was not detected. These findings supported the contention that there is no correlation between general Helicobacter spp density or numbers and gastritis in dogs.

OBJECTIVE To assess pulmonary hemodynamics and alveolar oxygenation in dogs anesthetized with propofol or isoflurane during one-lung ventilation (OLV) in a closed-thoracic experimental model. ANIMALS 6 healthy Beagles. PROCEDURES Dogs were anesthetized with each of 3 protocols (constant rate IV infusion of propofol [0.4 to 1.0 mg/kg/min], isoflurane at the minimum alveolar concentration [MAC], and isoflurane 1.5 MAC), with a 7-day washout period between anesthetic sessions. During each session, dogs were intubated with a double-lumen endotracheal tube, positioned in right lateral recumbency, and administered atracurium (0.1 to 0.2 mg/kg, IV, q 30 min) to allow mechanical ventilation throughout a 2-hour observation period. Dogs underwent two-lung ventilation for 30 minutes, OLV of the right lung for 1 hour, and two-lung ventilation for another 30 minutes. Pulmonary hemodynamic and blood gas variables were evaluated at predetermined times and compared among protocols and over time within each protocol. RESULTS Alveolar oxygenation was not impaired, and mean heart rate and pulmonary artery pressure and occlusion pressure were similar among the 3 protocols. One-lung ventilation caused a significant increase in the arteriovenous shunt fraction only when dogs were anesthetized with isoflurane at 1.5 MAC. Dogs developed respiratory acidosis, which was exacerbated by OLV, during all anesthetic sessions. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated pulmonary hemodynamics and alveolar oxygenation during OLV in a closed-thoracic model were similar regardless of whether dogs were anesthetized with propofol or isoflurane. One-lung ventilation can be successfully performed in dogs by use of a double-lumen endotracheal tube and either propofol or isoflurane.

In the last decades, the light had been shed on the importance of male reproduction and how to protect it from disease conditions and inflammation which may cause infertility. Accordingly, the mechanism underlying inflammation-mediated infertility must be well clarified. In the present study, an experimental model of acute inflammation in mature male albino rats was established by intraperitoneal (ip) injection of a single dose of lipopolysaccharides (LPS). Consequently, basic reproductive parameters were estimated after LPS administration. Blood samples were collected and assayed for serum testosterone levels. Semen was also analyzed for live sperm percent. Testes were removed for histopathological evaluation. The findings revealed that testosterone level in LPS-treated rats decreased significantly (P<0.05) compared to control rats at 6 and 12 hrs after injection. Meanwhile, serum testosterone recovered 72 hrs after injection. Moreover, live sperm percent decreased drastically in LPS-treated rats (P<0.001) compared with control rats at 6 and 12 hrs after LPS injection. Adverse effects of LPS on sperm vitality at 72 hrs after LPS injection were also found. Microscopic examination revealed that degenerative changes were observed in LPS-treated rats at 6 and 12 hrs. Most of histopathological findings returned to normal structure in LPS-treated rats at 72 hrs.