bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of radiographic positioning on interpretation of cubital joint congruity in dogs
Authors: Murphy Scott T. , Lewis Daniel D. , Shiroma Jonathan T. , Neuwirth Lisa A. , Parker Robert B. , Kubilis Paul S. 
Published: January 2024

Abstract

Objective
To ascertain effects of x-ray beam centering and limb position on apparent congruity of a normal cubital joint (elbow).

Animals
6 skeletally mature male Treeing Walker Coonhounds without physical, radiographic, or gross evidence of elbow abnormalities.

Procedure
Relative movement among humerus, radius, and ulna and measured joint space width on mediolateral and craniocaudal radiographic views was compared, using various x-ray beam centering and limb positions.

Results
Highest agreement and greatest certainty on subjective determination of congruity was for the flexed 90° mediolateral radiographic view with the x-ray beam centered on the elbow. Distortion artifact of the proximal ulnar measurements was significant when the x-ray beam was centered on the midpoint of the radius. On the mediolateral view, the humeroradial joint space became significantly wide when the elbow was flexed. On the craniocaudal view, maximal humeroradial joint space width was obtained when the x-ray beam bisected the angle of the joint or was angled +30° toward the humerus.

Conclusions
Artifact distortion of joint width affected objective and subjective assessment of elbow congruity when the limb was placed in extreme flexion or extension or when the x-ray beam was not centered over the area of interest. Optimal visualization of the humeroradial joint space on the craniocaudal view was achieved when the x-ray beam bisected the angle of the elbow or was slightly angled toward the humerus.

Clinical Relevance
Elbow congruity was best assessed on the flexed 90° lateral radiographic view with the x-ray beam centered on the joint. (Am J Vet Res 1998;59:1351–1357)
Normal variation in, and effect of 2% pilocarpine on, intraocular pressure and pupil size in female horses
Authors: van der Woerdt Alexandra , Gilger Brian C. , Wilkie David A. , Strauch Stephen M. , Orczeck Shawn M. 
Published: January 2024

Abstract

Objective
To determine normal variation in, and effect of 2% pilocarpine hydrochloride on, intraocular pressure (IOP) and pupil size in female horses during a specified period.

Animals
10 female horses with normotensive eyes.

Procedure
IOP and horizontal and vertical pupil size were measured on a single day between 8 am and 8 pm at hours 0, 0.5, 1, 2, 4, 6, 8, 10, and 12. Measurements were repeated after single-dose application of 2% pilocarpine to both eyes. IOP and pupil size were measured at 8 am and noon in a 5-day experiment of twice-daily application of 2% pilocarpine.

Results
Variation in IOP and pupil size was not significant between 8 am and 8 pm. Change in IOP or pupil size after a single dose of 2% pilocarpine also was not significant. In the multiple-dose experiment, the IOP at noon on the fifth day was significantly higher than the IOP in the morning on the first and second days. The IOP in the morning on the fifth day was significantly higher than the IOP in the morning and at noon on the first and second days. The IOP at noon on the fourth day was significantly higher than the morning IOP on the first and second days and at noon on the first day. The decrease in vertical pupil size was significant.

Conclusions
Between 8 am and 8 pm, variation in IOP and pupil size in normotensive eyes of horses is not significant. Two percent pilocarpine does not significantly change IOP between 8 am and 8 pm in clinically normal horses after a single dose or multiple twice-daily applications. After multiple twice-daily applications, a trend toward an increase in IOP was seen, and the decrease in vertical pupil size was significant. (Am J Vet Res 1998;59:1459–1462)
Effects of dopamine, dobutamine, dopexamine, phenylephrine, and saline solution on intramuscular blood flow and other cardiopulmonary variables in halothane-anesthetized ponies
Authors: Lee Y-H. L. , Clarke K. W. , Alibhai H. I. K. , Song D. 
Published: January 2024

Abstract

Objective
To evaluate the effect on intramuscular blood flow (IMBF) and hemodynamic variables of 4 antihypotensive agents given during anesthesia.

Animals
8 ponies.

Procedure
Halothane-anesthetized ponies (n = 6) positioned in lateral recumbency received, on separate occasions, infusions of each of the following 4 agents in serially increasing dosages or saline solution: phenylephrine hydrochloride (0.25, 0.5, 1, and 2 μg/kg of body weight), dopamine (2.5, 5, 10, and 20 μg/kg), dobutamine (1, 2.5, 5, and 10 μg/kg), and dopexamine (0.5, 1, 5, and 10 μg/kg). Changes in IMBF (by laser-Doppler flowmetry) in nondependent and dependent triceps brachii muscles and cardiopulmonary variables were measured.

Results
Phenylephrine at all dosages failed to improve IMBF or cardiac index (CI), but increased mean arterial pressure (MAP) and systemic vascular resistance (SVR); 2 ponies had forelimb lameness on recovery. Dopamine (10 μg/kg/min) increased Cl, MAP, and IMBF in the dependant muscle. A higher dose (20 μg/kg/min) caused cardiac arrhythmias and muscular tremor. Dobutamine increased Cl, MAP, and IMBF of both forelimbs, effects being significant for 2.5 μg/kg/min, with further improvement as the dosage increased. In 2 ponies, 10 μg of dobutamine/kg/min caused cardiac arrhythmias. Dopexamine (1 and 5 μg/kg/min) increased Cl, MAP, and IMBF in the nondependent muscle, and 10 μg/kg/min caused muscular tremor, sweating, and arrhythmias. SVR was reduced after infusion of dopamine, dobutamine, or dopexamine.

Conclusion
During anesthesia of equids, an increase in CI and MAP is necessary to improve IMBF in the dependant forelimb.

Clinical Relevance
Of the agents investigated, dobutamine proved the most consistent in improving IMBF. (Am J Vet Res 1998;59:1463–1472)
Hepatic blood flow in horses during the recuperative period from maximal exercise
Authors: Dyke Timothy M. , Hubbell John A. E. , Sams Richard A. , Hinchcliff Kenneth W. 
Published: January 2024

Abstract

Objective
To determine effects of walking or standing on hepatic blood flow of horses after brief, intense exercise.

Animals
6 adult Thoroughbreds (4 mares, 2 geldings).

Procedure
Horses were preconditioned on a treadmill to establish uniform level of fitness. Once fit, treadmill speed causing each horse to exercise at 120% of maximal oxygen consumption was determined and used in simulated races at 14-day intervals. In a three-way crossover study, horses were exercised at a speed inducing 120% of maximal oxygen consumption until fatigued or for a maximum of 2 minutes. Three interventions were studied: resting on the treadmill (REST), exercised then standing on the treadmill for 30 minutes (MS), and exercised then walking at 2 m/s for 30 minutes (MW). At 60 seconds after completion of exercise, bromsulphalein (BSP) was infused IV, and blood samples were collected every 2 minutes for 30 minutes for analysis of BSP concentration. Hematocrit and plasma total solids concentration were measured. Pharmacokinetic parameters were derived, using nonlinear regression, and were compared, using Friedman’s repeated measures analysis on ranks.

Results
Plasma BSP concentration was higher after exercise. Median hepatic blood flow (BSP clearance) decreased significantly from 23.8 (REST) to 20.7 (MS) and 18.7 (MW) ml/min/kg. Median steady-state volume of distribution of BSP decreased from 47.6 (REST) to 42.7 (MW) and 40.2 (MS) ml/kg. Differences among trials were not significant when horses walked or stood after exercise.

Conclusions
Hepatic blood flow and pharmacokinetics of BSP are markedly altered immediately after exercise. Limiting movement of horses during this period did not affect hepatic blood flow. (Am J Vet Res 1998;59:1476–1480)
Cardiopulmonary effects of bilateral hemithorax ventilation and diagnostic thoracoscopy in dogs
Authors: Faunt Karen K. , Cohn Leah A. , Jones Brent D. , Dodam John R. 
Published: January 2024

Abstract

Objective
To describe alterations in respiratory and cardiovascular variables during diagnostic thoracoscopy, using bilateral hemithorax ventilation with sustained pneumothorax.

Animals
7 adult dogs.

Procedure
Each dog was anesthetized and instrumented for 2 episodes of cardiopulmonary monitoring that were performed at an interval of more than 14 days. The first anesthetic episode served as a control procedure for the thoracoscopy treatment performed during the second anesthetic episode. Multiple cardiopulmonary variables were evaluated by comparing changes from baseline values within treatments and between treatments.

Results
Arterial oxygen tension decreased significantly from baseline values during thoracoscopy but was unchanged during sham treatment. Arterial carbon dioxide tension, clinical shunt fraction, and systemic mean arterial pressure increased during thoracoscopy. In contrast, these variables were unaffected by the sham treatment. Heart rate and cardiac index increased during sham and thoracoscopy treatments; however, the increase was significantly greater during thoracoscopy. Total peripheral vascular resistance significantly decreased from baseline values for both treatments, but the decrease was greater during thoracoscopy. Significant changes were not observed for oxyhemoglobin saturation or pulmonary vascular resistance during either treatment. Dogs recovered without major clinical complications.

Conclusions
Significant changes were found for several cardiopulmonary variables during bilateral hemithorax ventilation with sustained pneumothorax for diagnostic thoracoscopy of clinically normal dogs.

Clinical Relevance
Diagnostic thoracoscopy with bilateral hemithorax ventilation and sustained pneumothorax is well tolerated in clinically normal dogs and may provide a diagnostic modality enabling intrathoracic procedures with less morbidity than thoracotomy for dogs with intrathoracic disease. (Am J Vet Res 1998;59:1494–1498)
Population pharmacokinetics of gentamicin in horses
Authors: Martín-Jiménez Tomás , Papich Mark G. , Riviere Jim E. 
Published: January 2024

Abstract

Objective
To develop and validate a population pharmacokinetic model for gentamicin in horses, using retrospective clinical data.

Animals
62 horses that had been treated IV with multiple doses of gentamicin at our veterinary teaching hospital between 1987 and 1996.

Procedure
46 horses were assigned to the study group, and 16 to the validation group. Detailed history of dosage, sample collection times, and selected pathophysiologic variables were recorded for each patient. Samples were analyzed by use of a fluorescence polarization immunoassay method. Pharm-acostatistical analysis was conducted, using computer software. The predictive model correlates pharmacokinetic parameters to concomitant pathophysiologic variables and estimates the inter- and intraindividual variability in disposition.

Results
A two-compartment model best described the data. Clearance (Cl) was linearly correlated to body weight and serum creatinine concentration. Volume of the central compartment (Vdc) was linearly related to body weight. Interindividual coefficients of variability for Cl and Vdc were 24 and 16%, respectively. The residual variability (intraindividual) was 13%; mean prediction error percent (bias) was 2%; and mean absolute prediction error percent (precision) was 29%.

Conclusions
Population pharmacokinetic analysis allows study of the basic features of gentamicin disposition in horses with sparse data per individual. A considerable proportion of the pharmacokinetic variability of gentamicin in our study population was explained by differences in body weight and serum creatinine concentration.

Clinical Relevance
Population pharmacokinetics can be used to design first-dosage regimens according to the clinical characteristics of individual animals. Population pharmacokinetic models could also be included in Bayesian forecasting strategies to improve plasma concentration predictions in individual patients. (Am J Vet Res 1998;59:1589-1598)
Analysis of coagulation proteins as acute-phase reactants in horses with colic
Authors: Topper Michael J. , Prasse Keith W. 
Published: January 2024

Abstract

Objectives
To measure coagulation factor VIII:coagulant (F.VIII:C) and C1-esterase inhibitor (C1-INH), hemostasis-associated acute-phase reactant proteins, and coagulation factors VII (F.VII), IX (F.IX), and X (F.X), hemostasis proteins not associated with an acute-phase response, in a select population of horses with colic and hemostasis abnormalities, and presumed to have acute-phase changes. To compare these values and other routine hemostasis test results in the horses with colic with values for a population of healthy horses. To correlate the values of known equine acute-phase reactants, F.VIII:C and fibrinogen, to those of other tests of hemostasis. To identify hemostasis-associated acute-phase reactant proteins and gain insights into the effects the acute-phase response has on hemostatic abnormalities in horses with colic syndrome.

Sample Population
54 plasma samples from horses with colic attributable to inflammatory (n = 39) or strangulating (n = 15) intestinal disorders.

Procedure
Plasma samples were evaluated for activities of F.VII, F.VIII:C, F.IX, F.X, C1-INH, antithrombin III, protein C, plasminogen, and α2-antiplasmin (α2AP); fibrinogen concentration; and prothrombin (PT) and activated partial thromboplastin (APTT) times.

Results
Horses with colic had significantly higher fibrinogen concentration, greater α2AP and protein C activities, and longer PT and APTT than did healthy horses. Horses with colic also had significantly lower mean F.VII activity than did healthy horses. Significant positive correlations between fibrinogen concentration and F.VIII:C, C1-INH, and α2AP values, and between F.VIII:C activity and fibrinogen, C1-INH, α2AP, and plasminogen values were identified.

Conclusions
An acute-phase response contributes to changes observed in coagulation proteins in horses with colic attributable to inflammatory and strangulating intestinal disorders. The data suggest that plasminogen, α2AP, and C1-INH should be considered equine acute-phase proteins. (Am J Vet Res 1998;59:542–545)
Immunohistochemical characterization of immunoglobulin-containing cells and T cells in the colonic mucosa of healthy dogs
Authors: Jergens Albert E. , Gamet Yvan , Niyo Yosiya , Bailey Theodore B. , Brabec Marek , Smith Becky 
Published: January 2024

Abstract

Objectives
To quantitate numbers of immunoglobulin (Ig)-containing cells (IgA, IgG, and IgM) and T cells (CD3+, CD4+, and CD8+) in the colonic mucosa of healthy dogs, and to determine whether mean cell numbers differ among colonic regions.

Animals
10 clinically normal young adult mixed-breed dogs.

Procedure
Endoscopically obtained specimens of ascending, transverse, and descending colonic mucosa were stained specifically for IgA, IgG, and IgM heavy chains and T-cell antigens, CD3+, CD4+, and CD8+, using immunoperoxidase techniques. Morphometric analysis, performed by light microscopy, was used to quantitate numbers in these standardized areas of colonic mucosa. Data analysis allowed determination of mean cell numbers in each colonic region, as well as comparison of mean cell numbers among colonic regions.

Results
The CD3+ and CD8+ T cells were the predominant immune cell types in all colonic regions. In the mucosa, CD3+ T cells were significantly (P < 0.05) more numerous than CD8+ T cells, and CD8+ T cells were significantly (P < 0.05) more numerous than CD4+ T cells. The IgA-containing cells were significantly (P < 0.05) more numerous than IgG-containing cells, whereas IgM-containing cells were least numerous (P < 0.05). Differences in mean cell counts among colonic regions were not significant for Ig-containing cells or T cells.

Conclusions
Mean numbers of immune cells did not differ significantly among colonic regions in healthy dogs, although differences existed in mean populations of T cells and Ig-containing cells. The CD3+ and CD8+ T cells were the most numerous immune cell types in colonic mucosa.

Clinical Relevance
These quantitative data provide a basis for study of alterations in populations of mucosal immune cells and their possible contribution to the pathogenesis of gastrointestinal tract disease. (Am J Vet Res 1998;59:552–556)
Development and use of an enzyme-linked immunosorbent assay to monitor serum and urine acepromazine concentrations in Thoroghbreds, and possible changes associated with exercise
Authors: Chou Chi-Chung , Chen Chao-Ling , Asbury Atwood C. , Webb Alistair I. , Vickroy Thomas W. 
Published: January 2024

Abstract

Objectives
To develop an ELISA that is sensitive and suitable for measurement of immunoreactive acepromazine (ACP) in horse serum and urine and to determine the acute effects of exercise on immunoreactive ACP values in Thoroughbreds.

Animals
12 healthy Thoroughbreds (5 mares, 5 geldings, 2 stallions), aged 2 to 8 years.

Procedure
A commercially available antibody and a horseradish peroxidase-conjugated oxime derivative of immunoreactive ACP were used to develop a one-step ELISA. Horses were used in a crossover design study to evaluate possible effects of treadmill exercise on serum and urine ACP concentrations after a single (25 mg) IM injection of the drug.

Results
Immunoreactive ACP was detectable at concentrations as low as 50 pg/ml in serum and 100 pg/ml in urine, with intra- and interassay variabilities of 1.1 and 5.2%, respectively. The antibody had some cross-reactivity with a limited number of other phenothiazines. After drug administration, serum ACP immunoreactivity achieved a peak concentration (10.5 ng/ml) within 30 minutes and could be measured up to 48 hours in serum and 120 hours in urine. Although exercise had no significant effect on serum drug concentration, immunoreactive ACP disappeared more quickly (by 48 hours) from the urine of horses in the exercised group.

Conclusions
This one-step ELISA provides a simple and sensitive means to measure immunoreactive ACP in equine serum and urine. The ability to detect drug several days after administration of a low dose of ACP should augment efforts to control illicit use of this drug in performance horses. Potential changes in ACP kinetics after exercise warrant further study. (Am J Vet Res 1998;59:593–597)
Effect of xylazine, detomidine, and a combination of xylazine and butorphanol on equine duodenal motility
Authors: Merritt A. M. , Burrow J. A. , Hartless C. S. 
Published: January 2024

Abstract

Objective
To evaluate the effect on equine duodenal motility of some analgesic agents commonly used to treat colic.

Animals
4 healthy adult healthy horses—2 mares and 2 geldings—which were carrying an indwelling gastric cannula made of silastic rubber. One horse also carried 2 long-term indwelling bipolar electrodes that had been sutured onto the duodenum and jejunum.

Procedure
To ensure an empty stomach, solid food was withheld from horses for around 20 hours prior to an experiment. Using videoendoscopic guidance, an 8-F catheter with 3 small, discrete pressure sensors was passed through the gastric cannula and directed into the proximal portion of the duodenum. Deflection of the recording pen, to which the catheter was attached, indicated a motile event in that section. Drugs (treatment) were given into the jugular vein in a randomized block design, 1 treatment/experiment, after a 1-hour baseline recording. Treatments were: 2 ml of 0.9% NaCl, xylazine (XYL, 0.5 mg/kg of body weight), detomidine (DET, 0.0125 mg/kg), or a xylazine/butorphanol combination (XYB, 0.5/0.05 mg/kg). Each horse received each treatment twice. All positive pressure peaks > 5 mm of Hg recorded from the most proximal sensor on the catheter were counted in 15-minute blocks. Each mean 15-minute posttreatment value was compared with the baseline value for that specific treatment.

Results
There was no significant difference between baseline values. All treatments significantly (P < 0.05) reduced frequency of pressure peaks below their respective pretreatment values, but to variable degrees and durations. Comparatively, XYL had the least effect, with mild, though significant, reduction for only the first 30 posttreatment minutes; DET and XYB caused a significant marked reduction for 1 hour after treatment.

Conclusions
The profound suppressive effect of a routine dose of detomidine or xylazine/butorphanol combination on equine duodenal motility must be considered when using these agents for management of colic, especially when encouragement of intestinal motility is desirable. (Am J Vet Res 1998;59:619–623)
Relation between pathologic findings and cellular immune responses in sheep with naturally acquired paratuberculosis
Authors: Pérez V. , Tellechea J. , Corpa J. M. , Gutiérrez M. , Marín J. F. García 
Published: January 2024

Abstract

Objective
To investigate the relation between lesions and cellular immune response-based tests in sheep with naturally acquired paratuberculosis and to evaluate efficacy of an interferon-γ (IFN-γ) assay and the intradermal skin test.

Animals
110 and 88 adult sheep were used to evaluate the IFN-γ assay and skin test, respectively.

Procedure
Before euthanasia, heparinized blood was collected and incubated with avian purified protein derivative (PPD). Interferon-γ production was assessed, using a commercial enzyme immunoassay. Skin testing in the caudal fold also was performed, using avian PPD. Sensitivity and specificity of these techniques were evaluated, using histopathologic findings as reference.

Results
Of the sheep examined, 61 (55.4%) had lesions that were classified in 5 categories, according to location, extension, cellular types, and presence of acid-fast bacilli. Regarding cellular immunity test results, 55.4% of sheep with and 6.1% without pathologic changes had positive results of the IFN-γ assay. Skin test sensitivity (55.6%) and specificity (100%) were slightly greater.

Conclusion
Close association between pathologic findings and cellular immune response was apparent. Most sheep with focal (tuberculoid) and some with diffuse lesions (borderline tuberculoid), all with scant or no acid-fast bacilli in the intestine, had positive results of the IFN-γ assay and skin test. Most sheep with diffuse lesions and high numbers of bacilli (borderline lepromatous) were test negative.

Clinical Relevance
Cellular immune response-based and serologic tests are useful tools for seeking evidence of paratuberculosis. Each technique detects different types of immune-reacting sheep, and their simultaneous use may detect most infected animals. (Am J Vet Res 1999;60:123–127)