bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pharmacokinetic variables of mivacurium chloride after intravenous administration in dogs
Authors: Smith Lesley J. , Schwark Wayne S. , Cook D. Ryan , Moon Paula F. , Looney Andrea L. 
Published: January 2024

Abstract

Objective
To determine pharmacokinetic variables of mivacurium chloride after IV administration in dogs.

Animals
5 healthy Labrador Retrievers.

Procedure
Anesthesia was induced with thiopental and maintained with halothane in oxygen. Dogs were ventilated mechanically to an end-tidal PCO2 value between 35 and 40 mm Hg. Heart rate, direct blood pressure, and arterial pH were recorded throughout the experiment. Core temperature, end-tidal PCO2, and halothane concentration were kept constant throughout the experiment. Paired blood samples for determination of plasma cholinesterase activity were collected prior to administration of a bolus of mivacurium (0.05 mg/kg of body weight), which was administered IV during a 2-second period. Arterial blood samples were obtained for determination of plasma mivacurium concentration 0, 1, 3, 5, 10, 30, 60, 120, 150, and 180 minutes after administration of mivacurium. Blood was collected into tubes containing EDTA and 0.25% echothiophate. Mivacurium concentration was determined, using reversed-phase high-performance liquid chromatography.

Results
For the trans-trans isomer, mean ± SEM volume of distribution was 0.18 ± 0.024 L/kg, median half-life was 34.9 minutes (range, 26.7 to 53.5 minutes), and clearance was 12 ± 2 ml/min/kg. For the cis-trans isomer, values were 0.31 ± 0.05 L/kg, 43.4 minutes (range, 31.5 to 69.3 minutes), and 15 ± 2 ml/min/kg, respectively. Values for the cis-cis isomer were not calculated, because it was not detectable in plasma 60 minutes after mivacurium administration in all 5 dogs.

Conclusions and Clinical Relevance
The trans-trans and cis-trans isomers of mivacurium have a long half-life and slow clearance in healthy dogs anesthetized with halothane. (Am J Vet Res 1999;60:1051-1054)
Comparative pharmacokinetics of enrofloxacin in mice, rats, rabbits, sheep, and cows
Authors: Bregante Miguel A. , Saez Pilar , Aramayona Jose J. , Fraile Lorenzo , Garcia Maria A. , Solans Carlos 
Published: January 2024

Abstract

Objective
To compare pharmacokinetic variables of enrofloxacin (ENR) after IV administration in mice, rats, rabbits, sheep, and cows and to perform allometric analysis of ENR.

Animals
47 mice, 5 rats, 5 rabbits, 5 sheep, and 5 cows.

Procedure
Serially obtained plasma samples were assayed for enr concentration, using high-performance liquid chromatography. In vitro plasma protein binding was determined by ultrafiltration. Plasma enr concentration versus time curves were fitted by use of nonlinear least-squared regression analysis. Pharmacokinetic variables were correlated further with body weight.

Results
In all species studied, the best fit was obtained for a two-compartment open model; ENR half-life ranged from 89 minutes in mice to 169 minutes in cows. Volume of distribution was large in all species studied, with values ranging from 10.5 L/kg in mice to 1.5 L/kg in sheep. Body clearance ranged from 68.1 ml/min/kg for mice to 4.6 ml/min/kg for sheep. Unbound ENR was found to be (mean ± SD) 58 ± 2, 50 ± 6, 50 ± 2, 31 ± 2, and 40 ± 3% in plasma of mice, rats, rabbits, sheep, and cows, respectively. The only pharmacokinetic variables that could be correlated with body weight were elimination half-life, clearance, and volume of distribution. Allometric exponents denoting proportionality of half-life, body clearance, and volume of distribution with body weight were 0.06, 0.82, and 0.90, respectively.

Conclusions and Clinical Relevance
An allometric approach could provide a suitable method for determining a scale for ENR pharmacokinetics among various mammalian species. This would faciliatate the administration of appropriate doses of ENR to all animals. [Am J Vet Res 1999;60:1111–1116)
Colostral immunoglobulin concentrations in Holstein and Guernsey cows
Authors: Tyler Jeff W. , Steevens Barry J. , Hostetler Douglas E. , Holle Julie M. , Denbigh John L. 
Published: January 2024

Abstract

Objective
To compare the concentration of IgG in colostrum between Holstein and Guernsey cows and among cows of various lactations.

Design
Cross-sectional cohort study.

Sample Population
Colostrum samples from 77 Holstein and 24 Guernsey cows.

Procedure
Colostrum samples were obtained from 101 cows. Colostral IgG concentration was determined, using a radial immunodiffusion assay. Regression analysis was used to determine the effect of breed and lactation number on colostral IgG concentration. Survival analysis and t-tests were used to compare the proportion of colostrum samples that would provide 100 g of IgG for various volumes of colostral intake.

Results
Guernsey cows produced 36.4 g of IgG/L of colostrum more than that of Holstein cows. Cows in the third or greater lactation produced 19.5 g of IgG/L of colostrum more than that of first-lactation cows. The IgG concentration of colostrum produced by second-lactation cows did not differ significantly from that produced by first-lactation cows. The colostral IgG concentration of these Holstein and Guernsey cows was higher than values that have been reported elsewhere.

Conclusions and Clinical Relevance
Volume of colostrum needed to meet IgG intake goals is probably lower for Guernsey cows than Holstein cows. Colostrum from first-lactation cows was adequate in IgG content. The practice of discarding colostrum from first-lactation cows on the basis of inadequate IgG content was not justified in this study. (Am J Vet Res 1999;60:1136–1139)
Effect of transportation and feed withdrawal on shedding of Salmonella Typhimurium among experimentally infected pigs
Authors: Isaacson Richard E. , Firkins Lawrence D. , Weigel Ronald M. , Zuckermann Federico A. , DiPietro Joseph A. 
Published: January 2024

Abstract

Objective
To determine whether stress associated with transportation or feed withdrawal increased fecal shedding of Salmonella Typhimurium among pigs experimentally infected with the organism.

Animals
86 healthy pigs.

Procedure
Pigs were challenge exposed with Salmonella Typhimurium at 4 weeks old and reared conventionally. When pigs reached market weight, they were assigned to groups and subjected to various combinations of transportation and feed withdrawal. Ileocecal contents were collected after slaughter and tested for Salmonella Typhimurium.

Results
Salmonella Typhimurium was not detected in feces collected from pigs just prior to slaughter. When feed was withheld for 24 hours prior to slaughter, the proportion of transported pigs with Salmonella Typhimurium in ileocecal contents at the time of slaughter was not significantly different from the proportion of nontransported pigs. However, when feed was not withheld prior to slaughter, the proportion of transported pigs with Salmonella Typhimurium in ileocecal contents at the time of slaughter was significantly higher than the proportion of nontransported pigs.

Conclusions and Clinical Relevance
When carrier pigs remained on feed, transportation stress increased the proportion positive for Salmonella sp. On the basis of results reported here, it is suggested that producers withhold feed from pigs for 24 hours prior to transportation to a slaughter plant. (Am J Vet Res 1999;60:1155–1158)
Comparison of clinical signs and hemodynamic variables used to monitor rabbits during halothane- and isoflurane-induced anesthesia
Authors: Imai Ayako , Steffey Eugene P. , Ilkiw Jan E. , Farver Thomas B. 
Published: January 2024

Abstract

Objective
To characterize variables used to monitor rabbits during inhalation anesthesia.

Animals
8 male New Zealand White rabbits.

Procedure
Rabbits were similarly anesthetized with halothane (HAL) or isoflurane (ISO) in a crossover study; half received HAL followed by ISO, and the protocol was reversed for the remaining rabbits. After induction, minimum alveolar concentration (MAC) was determined for each agent, using the tail-clamp method, and variables were recorded at 0.8, 1.0, 1.5, and 2.0 MAC (order randomized).

Results
Mean ± sem mac was 1.42 ± 0.05 and 2.07 ± 0.09% for hal and iso, respectively. Directly measured auricular mean arterial blood pressure was 52.8 ± 5.6 and 54.8 ± 6.1 mm Hg at 0.8 mac for hal and iso, respectively, and decreased from these values in a parallel dose-dependent manner. Respiratory frequency remained constant (range, 69 to 78 breaths/min) over the range of hal doses but incrementally decreased from a mean of 53 (at 0.8 mac) to 32 breaths/min (at 2.0 mac) for iso. The Paco2 was similar at 0.8 mac for hal and iso and progressively increased with increasing doses of both agents; Paco2 at 2.0 mac for iso was significantly greater than that at 2.0 mac for hal (79.8 ± 13.7 vs 54.9 ± 4.0 mm Hg, respectively). Eyelid aperture consistently increased in a dose-dependent manner for both anesthetics.

Conclusions
Arterial blood pressure, Paco2, and eyelid aperture consistently and predictably changed in rabbits in response to changes in anesthetic doses. The magnitude of respiratory depression was greater for iso than for hal. (Am J Vet Res 1999;60:1189–1195)
A technique for evaluating analgesia in conscious perching birds
Authors: Paul-Murphy Joanne R. , Brunson David B. , Miletic Vjekoslav 
Published: January 2024

Abstract

Objective
To develop a technique for objective assessment of modulation of nociperception in conscious perching birds.

Animals
31 adult African grey parrots.

Procedure
Birds were randomly assigned to receive saline (0.9% NaCl) solution (n = 10), butorphanol tartrate (11), or buprenorphine hydrochloride (10), IM. Birds were fitted with a surface electrode on the medial metatarsus of 1 leg. An electrical stimulus was delivered to the bird’s foot through an aluminum surface on half of the perch. The alternate side of the perch delivered a noxious thermal stimulus. A withdrawal response to either stimulus was recorded when the bird lifted its foot or vigorously flinched its wings.

Results
Responses to thermal stimuli were extremely variable during baseline testing and after administration of drugs. Thus, significant differences were not detected after drug injection. In contrast, responses to an electrical stimulus were predictable with much less variation.

Conclusions and Clinical Relevance
This method and device allowed for the reliable determination of withdrawal threshold in perching birds. Use of this technique for objective assessment of modulation of nociperception in conscious perching birds will enable assessment of analgesic drugs. (Am J Vet Res 1999;60:1213–1217)
Pharmacologic effects of epidural versus intramuscular administration of detomidine in cattle
Authors: Prado Maria E. , Streeter Robert N. , Mandsager Ronald E. , Shawley Richard V. , Claypool P. L. 
Published: January 2024

Abstract

Objectives
To determine whether epidural administration of detomidine hydrochloride to cattle induced analgesia of the perineum and to compare analgesic and systemic effects of epidural versus IM administration of detomidine at a dose of 40 μg/kg in cattle.

Animals
18 healthy adult cows.

Procedure
6 cows were given detomidine by epidural administration, 6 were given detomidine IM, and 6 (control group) were not given detomidine. Analgesia was assessed by determining responses to needle pinpricks in the perineum and flank and by applying electrical stimuli to the perineum and flank and determining the voltage that induced an avoidance response. Degree of sedation and ataxia were scored, and mean arterial pressure, heart rate, respiratory rate, and frequency of ruminal contractions were measured.

Results
Epidural and IM administration of detomidine induced comparable degrees of analgesia of the perineum and flank, accompanied by moderate sedation and ataxia, hypertension, cardiorespiratory depression, and rumen hypomotility.

Conclusions and Clinical Relevance
Epidural and IM administration of detomidine at a dose of 40 µg/kg induced similar analgesic and systemic effects in cattle. Epidural administration of detomidine did not appear to be advantageous over IM administration. (Am J Vet Res 1999;60:1242–1247)
Susceptibility of equine erythrocytes to oxidant-induced rheologic alterations
Authors: Baskurt Oguz K. , Meiselman Herbert J. 
Published: January 2024

Abstract

Objective
To evaluate the rheologic responses of equine versus human RBC to oxidant stress induced by superoxide anions.

Sample Population
Equine blood samples were obtained from 8 healthy, 3- to 6-year-old various breed horses of either sex; human blood samples were obtained from 8 healthy adults.

Procedure
Washed RBC were exposed to superoxide anions generated by the xanthine oxidase (XO)-hypoxanthine system (XO activity of 0 to 0.1 U/ml). Deformability of RBC was assessed by ektacytometry, and RBC aggregation was measured in autologous plasma or 3% solution of dextran 70 via a defined-shear photometric technique.

Results
Equine RBC had XO dose-dependent increases in methemoglobin concentration that were greater by 60 to 110% than in human RBC and an enhanced tendency for echinocyte formation (ie, 40% echinocyte formation at highest activity of XO). Oxidant stress reduced deformability (ie, increased rigidity) for equine and human RBC with the effect more prominent for equine RBC. Equine RBC aggregation had a biphasic response with a significant increase in plasma and dextran 70 at low XO activities and inhibition at high activities; echinocytes were incorporated into equine, but not human, RBC aggregates.

Conclusions and Clinical Relevance
Compared with human RBC, equine RBC are more sensitive to oxidant damage as judged by the extent of methemoglobin formation, alteration of aggregation, and reduction of cellular deformability. The high susceptibility of equine RBC to oxidant damage, and the resulting hemorheologic alterations, may have important consequences for tissue perfusion and cardiovascular adequacy in horses; they may be of particular relevance in physiologic or pathophysiologic changes associated with increased oxidant stress. (Am J Vet Res 1999;60:1301–1306)
Characterization of swimming motility and identification of flagellar proteins in Salmonella pullorum isolates
Authors: Chaubal Lisa H. , Holt Peter S. 
Published: January 2024

Abstract

Objective
To identify swimming motility in Salmonella pullorum isolates and to characterize the flagellar proteins produced by motile isolates.

Sample population
30 S pullorum isolates and isolates of 7 other Salmonella sp.

Procedure
Salmonella pullorum isolates were inoculated into high motility medium to evaluate swimming motility. Putative flagellar proteins were purified from the organisms and analyzed by means of gel electrophoresis and western blotting procedures, using various antisera specific for flagellar proteins. Antisera shown to be reactive with putative flagellar proteins were incorporated into the growth medium to examine their effects on motility of the isolates.

Results
All S pullorum isolates had evidence of swimming motility. Two putative flagellar proteins were purified from 2 of the S pullorum isolates: a 60 to 62 kd protein shown to react with antiserum specific for type y flagellar protein, and a 58 to 59 kd protein shown to react with antiserum specific for type d flagellar protein and with antibody reactive to a highly conserved flagellar epitope found on various Enterobacteriaceae. Antiserum specific for type d flagellar protein inhibited swimming motility of S pullorum isolates, but antiserum specific for type y flagellar protein did not.

Conclusions
Results suggest that S pullorum isolates can be induced to manifest swimming motility when grown on medium with a low agar concentration and possess a 58 to 59 kd protein of d serotype and a second protein of 60 to 62 kd that also may be a flagellar protein. (Am J Vet Res 1999;60:1322–1327)
Pharmacokinetic variables and tissue residues of enrofloxacin and ciprofloxacin in healthy pigs
Authors: Anadón Arturo , Martínez-Larrañaga Maria R. , Díaz Maria J. , Fernández-Cruz Maria L. , Martínez Maria A. , Frejo Maria T. , Martínez Marta , Iturbe Javier , Tafur Mcallister 
Published: January 2024

Abstract

Objectives
To determine pharmacokinetics of enrofloxacin and its metabolite ciprofloxacin after a single IV and IM administration of enrofloxacin and tissue residues after serial daily IM administration of enrofloxacin in pigs.

Animals
20 healthy male pigs.

Procedure
8 pigs were used in a crossover design to investigate pharmacokinetics of enrofloxacin after a single IV and IM administration (2.5 mg/kg of body weight). Twelve pigs were used to study tissue residues; they were given daily doses of enrofloxacin (2.5 mg/kg, IM for 3 days). Plasma and tissue concentrations of enrofloxacin and ciprofloxacin were determined. Residues of enrofloxacin and ciprofloxacin were measured in fat, kidney, liver, and muscle.

Results
Mean (± SD) elimination half-life and mean residence time of enrofloxacin in plasma were 9.64 ± 1.49 and 12.77 ±2.15 hours, respectively, after IV administration and 12.06 ± 0.68 and 17.15 ± 1.04 hours, respectively, after IM administration. Half-life at α phase of enrofloxacin was 0.23 ± 0.05 and 1.94 ± 0.70 hours for IV and IM administration, respectively. Maximal plasma concentration was 1.17 ± 0.23 µg/ml, and interval from injection until maximum concentration was 1.81 ± 0.23 hours. Renal and hepatic concentrations of enrofloxacin (0.012 to 0.017 µg/g) persisted for 10 days; however, at that time, ciprofloxacin residues were not detected in other tissues.

Conclusions and Clinical Relevance
Enrofloxacin administered IM at a dosage of 2.5 mg/kg for 3 successive days, with a withdrawal time of 10 days, resulted in a sum of concentrations of enrofloxacin and ciprofloxacin that were less than the European Union maximal residue limit of 30 ng/g in edible tissues. (Am J Vet Res 1999;60:1377–1382)
Behavior of stabled horses provided continuous or intermittent access to drinking water
Authors: McDonnell Sue M. , Freeman Douglas A. , Cymbaluk Nadia F. , Schott Harold C. , Hinchcliff Kenneth , Kyle Beth 
Published: January 2024

Abstract

Objective
To compare quantitative measures and clinical assessments of behavior as an indication of psychologic well-being of stabled horses provided drinking water continuously or via 1 of 3 intermittent delivery systems.

Animals
22 Quarter Horse (QH) or QH-crossbred mares and 17 Belgian or Belgian-crossbred mares (study 1) and 24 QH or QH-crossbred mares and 18 Belgian or Belgian-crossbred mares (study 2).

Procedure
Stabled horses were provided water continuously or via 1 of 3 intermittent water delivery systems in 2 study periods during a 2-year period. Continuous 24-hour videotaped samples were used to compare quantitative measures and clinical assessments of behavior among groups provided water by the various water delivery systems.

Results
All horses had clinically normal behavior. Significant differences in well being were not detected among groups provided water by the various delivery systems.

Conclusions and Clinical Relevance
Various continuous and intermittent water delivery systems can provide adequately for the psychologic well-being of stabled horses. (Am J Vet Res 1999;60:1451–1456)
Quantification of left ventricular diastolic wall motion by Doppler tissue imaging in healthy cats and cats with cardiomyopathy
Authors: Gavaghan Brad J. , Kittleson Mark D. , Fisher Kristian J. , Kass Philip H. , Gavaghan Michelle A. 
Published: January 2024

Abstract

Objective
To assess Doppler tissue imaging (DTI) for evaluating left ventricular diastolic wall motion in healthy cats and cats with cardiomyopathy.

Animals
20 healthy cats, 9 cats with hypertrophic cardiomyopathy (HCM), and 9 cats with unclassified cardiomyopathy (UCM).

Procedure
A pulsed wave DTI sample gate was positioned at a subendocardial region of the left ventricular free wall in the short axis view and at the lateral mitral annulus in the apical 4-chamber view. Indices of diastolic wall motion were measured, including peak diastolic velocity (PDV), mean rate of acceleration and deceleration of the maximal diastolic waveform (MDWaccel and MDWdecel, respectively), and isovolumetric relaxation time (IVRT).

Results
The PDV of cats with HCM and 6 of 9 cats with UCM was significantly decreased, compared with that of healthy cats. In the 3 cats with UCM that had a PDV that was not different from healthy cats, MDWaccel and MDWdecel were greater, and IVRT was shorter than those of healthy cats. The IVRT in cats with HCM was longer than that of other cats.

Conclusions and Clinical Relevance
Indices of diastolic function in cats with HCM, and in many cats with UCM, differed from those of healthy cats and were similar to those reported in humans with HCM and restrictive cardiomyopathy, respectively. However, the hemodynamic abnormality was not the same for all cats with UCM; some cats with an enlarged left atrium and a normal left ventricle (ie, UCM) had abnormal left ventricular wall motion consistent with restrictive cardiomyopathy while others did not. (Am J Vet Res 1999;60:1478–1486)
Effect of enalapril on blood pressure, renal function, and the renin-angiotensin-aldosterone system in cats with autosomal dominant polycystic kidney disease
Authors: Miller Rita H. , Lehmkuhl Linda B. , Smeak Daniel D. , DiBartola Stephen P. , Radin Judith 
Published: January 2024

Abstract

Objective
To evaluate blood pressure, renal function, and the renin-angiotensin-aldosterone system (RAAS) in cats with autosomal dominant polycystic kidney disease (ADPKD) and to assess the effect of enalapril on these variables.

Animals
6 cats with ADPKD and 6 age-matched healthy cats.

Procedure
To measure blood pressure and heart rate, a radiotelemetry catheter was placed in the left femoral artery of each cat. Baseline data collection included 24-hour blood pressure, heart rate, and motor activity. Blood was then collected for analysis of RAAS status and renal function. Enalapril (0.5 mg/kg of body weight, PO, q 24 h) was administered for 1 week, and data collection was repeated.

Results
Differences in baseline blood pressure, heart rate, motor activity, RAAS status, and renal function were not detected between cats with ADPKD and control cats. Hypertension was not documented in cats with ADPKD. Blood pressure was significantly reduced for 15 to 17 hours after treatment with enalapril in both groups. Administration of enalapril also resulted in significant increases in plasma renin activity and significant decreases in angiotensin converting enzyme activity and atrial natriuretic peptide concentration but only minimal changes in glomerular filtration rate and effective renal plasma flow in both groups of cats.

Conclusions and Clinical Relevance
Although hypertension is common in humans with ADPKD, cats with ADPKD were normotensive. Treatment with enalapril (0.5 mg/kg, PO, q 24 h) significantly reduced blood pressure in normotensive healthy cats and cats with ADPKD, and resulted in predictable changes in RAAS enzyme activities and hormone concentrations. Enalapril had minimal effects on renal function. (Am J Vet Res 1999;60:1516–1525)