bluuebunny/crossref_metadata_2025_split huggingface dataset:
Use of long-term vaccination with a killed vaccine to prevent fecal shedding of Mycobacterium avium subsp paratuberculosis in dairy herds
Authors: Kalis Cees H. J. , Hesselink Jan Willem , Barkema Herman W. , Collins Michael T. 
Published: December 2005

AbstractObjectives—To determine whether vaccination with a killed vaccine prevents fecal shedding ofMycobacterium aviumsubspparatuberculosis, to compare effectiveness of a culture and cull program in vaccinated and nonvaccinated herds, and to compare paratuberculosis-related preventive management in vaccinated and nonvaccinated herds.Sample Population—58 commercial Dutch dairy herds.Design—Cross-sectional study (study A) in vaccinated (n = 25) and nonvaccinated (29) herds of dairy cows. Longitudinal study (study B) in vaccinated (n = 2) and nonvaccinated (2) herds of dairy cows.Procedure—In study A, fecal samples were obtained from adult cows in herds with and without a history of vaccination with a killed vaccine. Management measures were evaluated. In study B, fecal samples were obtained 4 times at 6-month intervals from cows older than 6 months. Cows that had positive test results were removed from the herd directly after the outcome of the culture.Results—In study A, differences were not detected among the 25 herds that were vaccinated; culture results were positive forM aviumsubspparatuberculosisin 4.4% of herds. In 29 herds that had not been vaccinated, culture results were positive in 6.7%. In study B, the percentage of positive results on culture decreased from 10.9% and 5.7% to 3.5% and 0%, respectively in the 2 vaccinated herds. In the 2 nonvaccinated herds, percentages decreased from 6.1% and 16.5% to 0% and 2.3%, respectively. Management practices were different between herds that were vaccinated and herds that were not; owners of herds that were not vaccinated followed more preventive management procedures and practiced less feeding of raw milk to calves.Conclusions and Clinical Relevance—Vaccination of calves with a killed vaccine does not prevent transmission ofM aviumsubspparatuberculosis; therefore, hygienic practices remain essential in herd management. (Am J Vet Res2001;62:270–274)
Kinetics of mRNA expression of alkaline phosphatase isoenzymes in hepatic tissues from glucocorticoid-treated dogs
Authors: Wiedmeyer Charles E. , Solter Philip F. , Hoffmann Walter E. 
Published: December 2005

AbstractObjective—To clone segments of the canine liver alkaline phosphatase (LALP) and corticosteroidinduced alkaline phosphatase (CIALP) genes and use those clones to determine the tissue source of CIALP, the kinetics of LALP and CIALP mRNA expression for glucocorticoid-treated dogs, and the correlation between LALP and CIALP transcript concentrations and isoenzyme activities.Sample Population—Tissues obtained from 7 dogs treated with prednisone (1 mg/kg, SC, q 24 h) for up to 32 days and 1 untreated (control) dog.Procedure—Gene segments of LALP and CIALP were obtained by reverse transcription-polymerase chain reaction (RT-PCR) assay. The tissue source of CIALP and IALP mRNA was determined by northern blot analysis of tissues from 1 of the glucocorticoidtreated dogs. Hepatic tissues and serum samples were obtained from the 6 remaining glucocorticoidtreated dogs on days 0, 2, 5, 10, and 32 of prednisone treatment, and relative expression of LALP and CIALP mRNA was correlated with LALP and CIALP activity.Results—A 2,246-base pair (bp) segment of canine LALP and a 1,338-bp segment of CIALP were cloned. Northern blot analysis revealed CIALP mRNA expression in hepatic tissues only after glucocorticoid treatment. Kinetics of LALP and CIALP mRNA expression in the liver of glucocorticoid-treated dogs paralleled liver and serum activities of LALP and CIALP.Conclusions and Clinical Relevance—The liver is the most likely source for CIALP in dogs. Analysis of kinetics of serum and hepatic LALP and CIALP mRNA suggests that after glucocorticoid treatment, both are regulated by modification of mRNA transcript concentrations, possibly through differing mechanisms. (Am J Vet Res2002;63:1089–1095)
Effectiveness of glyceryl trinitrate for enhancing digital submural perfusion in horses
Authors: Hoff Tracy K. , Hood David M. , Wagner Ilka P. 
Published: December 2005

AbstractObjective—To evaluate the clinical efficacy of topically administered glyceryl trinitrate (GTN) for inducing digital submural vasodilation in clinically normal horses.Animals—7 adult horses without foot abnormalities.Procedures—A concurrent-control crossover design was used to determine whether topical application of GTN ointment for prevention or treatment of laminitis would result in a detectable increase in digital perfusion. Heat-acclimated horses instumented for detection of wall surface temperature (HWST), mean systemic pressure, and heart rate were used. Horses were exposed to cold to induce digital vasoconstriction and treated with GTN in an attempt to induce digital vasodilation.Results—Application of GTN failed to induce an increase in digital submural perfusion but did induce a mild decrease in mean systemic pressure.Conclusionss and Clinical Relevance—Topical application of 60 mg of GTN as a 2% ointment on the skin over the major vasculature in the region of the proximal interphalangeal joint (pastern) of horses was not effective in significantly increasing digital perfusion. A decrease in mean systemic pressure following treatment was observed, implying that the drug was absorbed. Use of GTN may result in a decrease in digital submural perfusion secondary to induction of peripheral constriction or a decrease in digital perfusion pressure. (Am J Vet Res2002;63:648–652)
Examination of nasopharyngeal and tracheal somatosensory evoked potential recordings in dogs
Authors: Mikó László , Székely György M. , Dobai József G. , Mikó Irén , Csécsei György I. 
Published: December 2005

AbstractObjective—To investigate the value of nasopharyngeal and tracheal recordings of somatosensory evoked potentials (SSEP) in anesthetized dogs.Animals—10 healthy mixed-breed dogs (5 males and 5 females).Procedure—Square-ware electrical stimuli (50 microseconds duration, 4Hz) were delivered through bipolar surface electrodes to the median nerve of the right forelimb with 7 to 12 mA constant current. The SSEP were recorded with soft electrodes placed on the epipharynx and dorsal wall of the trachea, respectively. Traditional scalp and neck recordings of SSEP were also performed, using SC-inserted needle electrodes. The potentials recorded dorsally and ventrally from the neuraxis were compared to assess the application of these signals for intraoperative neurophysiologic monitoring.Results—Electrical stimulation of the median nerve resulted in multiphasic potentials recorded from all 4 recording sites. Latency and phase shifts were observed between the far-field potentials placed ventrally and dorsally from the neuraxis.Conclusions and Clinical Relevance—Potentials recorded with nasopharyngeal and tracheal electrodes are regarded suitable for intraoperative neurophysiologic monitoring in anesthized dogs. (Am J Vet Res2002; 63:669–672)
Effects of formaldehyde fixation on equine platelets using flow cytometric methods to evaluate markers of platelet activation
Authors: Kingston Janene K. , Bayly Warwick M. , Sellon Debra C. , Meyers Kenneth M. , Wardrop K. Jane 
Published: December 2005

AbstractObjective—To investigate the effects of formaldehyde fixation on equine platelets using flow cytometric methods to evaluate markers of platelet activation.Sample Population—Blood samples from 6 Thoroughbreds.Procedure—The degree of fluorescence associated with binding of fluorescein isothiocyanate (FITC)-conjugated anti-human fibrinogen antibody and FITCannexin V in unactivated and adenosine diphosphate (ADP)-, platelet activating factor (PAF)-, and A23187- activated platelet samples in unfixed and 0.5, 1.0, and 2.0% formaldehyde-fixed samples was assessed by use of flow cytometry.Results—In samples incubated with FITC-anti-human fibrinogen antibody prior to fixation, addition of 2.0% formaldehyde resulted in a 30% increase in total fluorescence in ADP- and PAF-activated samples and a 60% increase in A23187-activated samples. Fixation for 24 hours prior to addition of antibody resulted in reduced fluorescence of samples containing antihuman fibrinogen antibody for all 3 concentrations of formaldehyde in PAF-activated samples. The addition of all 3 concentrations of formaldehyde after incubation with FITC-annexin V resulted in significant increases in fluorescence in unactivated and activated platelet samples. As length of fixation time increased, there was a gradual increase in fluorescence that was significant at 24 hours.Conclusion and Clinical Relevance—Because fixation with 2.0% formaldehyde results in significant changes in fluorescence in activated platelet samples containing anti-fibrinogen antibody, lower concentrations of formaldehyde should be used to fix equine platelet samples. Formaldehyde-fixed platelet samples should be analyzed within 12 hours of fixation to avoid artifactual increases in fluorescence. Fixation of samples containing FITC-annexin V should be avoided because of significant increases in fluorescence that may interfere with interpretation of results. (Am J Vet Res2002;63:840–844)
Expression of bone morphogenetic protein-6 and -2 and a bone morphogenetic protein antagonist in horses with naturally acquired osteochondrosis
Authors: Semevolos Stacy A. , Nixon Alan J. , Strassheim M. Lisa 
Published: December 2005

AbstractObjective—To determine the mRNA expression of bone morphogenetic protein (BMP)-6 and -2 and a BMP antagonist (Noggin) in horses with osteochondrosis.Sample Population—Samples of articular cartilage from affected stifle or shoulder joints of 10 immature horses with naturally acquired osteochondrosis and corresponding joints of 9 clinically normal horses of similar age; additionally, samples of distal femoral growth plate cartilage and distal femoral articular cartilage were obtained from a normal equine fetus.Procedure—Cartilage specimens were snap-frozen in liquid nitrogen, and total RNA was isolated. Adjacent specimens were fixed in 4% paraformaldehyde for histologic examination. Expression of BMP-6, BMP-2, and Noggin mRNA was evaluated by real-time quantitative polymerase chain reaction (PCR) assays. Spatial tissue mRNA expression of BMP-6 was determined by in situ hybridization.Results—Nucleotide sequences were obtained for portions of the BMP-6 propeptide and mature peptide region, as well as the signal and mature peptide region of Noggin. Expression of BMP-6, BMP-2, and Noggin mRNA was found to be similar in cartilage from normal and osteochondrosis-affected horses. Spatial expression of BMP-6 correlated with the middle and deep layers of articular cartilage; no differences were observed in overall expression between cartilage specimens from the 2 groups of horses. No expression of BMP-6 was found in the superficial layer, subchondral bone, or osteochondrosis-affected cleft fibrous tissue.Conclusions and Clinical Relevance—Although these signaling peptides may play important roles in cartilage differentiation, results did not provide evidence to suggest that they are involved in the disease process of osteochondrosis. (Am J Vet Res2004;65:110–115)
Characterization of gelatinases in bronchoalveolar lavage fluid and gelatinases produced by alveolar macrophages isolated from healthy calves
Authors: Lakritz Jeffrey , Marsh Antoinette E. , Cockrell Mary , Smith Michael F. , Tyler Jeff W. 
Published: December 2005

AbstractObjective—To characterize gelatinases in bronchoalveolar lavage fluid (BALF) and gelatinases produced by alveolar macrophages of healthy calves.Sample Population—Samples of BALF and alveolar macrophages obtained from 20 healthy 2-month-old calves.Procedure—BALF was examined by use of gelatin zymography and immunoblotting to detect gelatinases and tissue inhibitor of metalloproteinase (TIMP)-1 and -2. Cultured alveolar macrophages were stimulated with lipopolysaccharide (LPS), and conditioned medium was subjected to zymography. Alveolar macrophage RNA was used for reverse transcriptasepolymerase chain reaction assay of matrix metalloproteinases (MMPs), cyclooxygenase-2, and inducible nitric oxide synthase.Results—Gelatinolytic activity in BALF was evident at 92 kd (14/20 calves; latent MMP-9) and 72 kd (18/20; latent MMP-2). Gelatinolytic activity was evident at 82 kd (10/20 calves; active MMP-9) and 62 kd (17/20; active MMP-2). Gelatinases were inhibited by metal chelators but not serine protease inhibitors. Immunoblotting of BALF protein and conditioned medium confirmed the MMP-2 and -9 proteins. Endogenous inhibitors (ie, TIMPs) were detected in BALF from all calves (TIMP-1) or BALF from only 4 calves (TIMP-2). Cultured alveolar macrophages expressed detectable amounts of MMP-9 mRNA but not MMP-2 mRNA.Conclusions and Clinical Relevance—Healthy calves have detectable amounts of the gelatinases MMP-2 and -9 in BALF. Endogenous inhibitors of MMPs were detected in BALF (ie, TIMP-1, all calves; TIMP-2, 4 calves). Lipopolysaccharide-stimulated alveolar macrophages express MMP-9 but not MMP-2 mRNA. The role of proteases in the pathogenesis of lung injury associated with pneumonia has yet to be determined. (Am J Vet Res2004;65:163–172)
Effects of insulin-like growth factor-II on the mitogenic and metabolic activities of equine articular cartilage with and without interleukin 1-β
Authors: Davenport-Goodall Celia L. M. , Boston Raymond C. , Richardson Dean W. 
Published: December 2005

AbstractObjective—To investigate the effects of insulin-like growth factor-II (IGF-II) on DNA and glycosaminoglycan (GAG) synthesis and the expression of matrix-related genes in equine articular cartilage explants and chondrocytes, respectively, with and without interleukin 1-β (IL1-β).Sample Population—Articular cartilage from 12 adult horses.Procedure—Articular cartilage was incubated in standard media with and without equine IL1-β (10 ng/mL) containing various concentrations of IGF-II for 72 hours. Synthesis of DNA and GAG was determined by incorporation of thymidine labeled with radioactive hydrogen (3H) and sulfate labeled with radioactive sulfur (35S), respectively. Total GAG content of the explants and spent media was determined by use of the 1,9-dimethylmethylene blue assay. Northern blots of RNA from cultured equine articular cartilage chondrocytes were hybridized with cDNA of major matrix molecules.Results—Insulin-like growth factor-II stimulated DNA and GAG synthesis at concentrations of 25 and 50 ng/mL, respectively. In cartilage explants conditioned with IL1-β, IGF-II stimulated DNA and GAG synthesis at concentrations of 500 and 50 ng/mL, respectively. Insulin-like growth factor-II had no effect on total GAG content as determined by the 1,9-dimethylmethylene blue assay. No specific effects on steady-state levels of messenger RNAs were observed.Conclusions and Clinical Relevance—Insulin-like growth factor-II stimulated DNA and GAG synthesis in equine adult cartilage and may have potential application in vivo. (Am J Vet Res2004;65:238–244)
Assessment of leukotriene B4 production in leukocytes from horses with recurrent airway obstruction
Authors: Lindberg Åsa , Robinson N. Edward , Näsman-Glaser Barbro , Jensen-Waern Marianne , Lindgren Jan Åke 
Published: December 2005

Abstract

Objective—To determine the ex vivo leukotriene (LT)
biosynthesis in peripheral blood neutrophils (PBNs)
and inflammatory cells in bronchoalveolar lavage fluid
(BALF) obtained from horses affected with recurrent
airway obstruction (RAO).

Animals—6 RAO-affected and 6 control horses.

Procedure—Before and 6, 24, and 48 hours after
stabling, disease severity was determined subjectively
by clinical and mucus scores and measurement of
the maximal change in pleural pressure (ΔPplmax);
PBNs were isolated and BALF samples were examined
cytologically. The PBN and BALF cells were activated
with a calcium ionophore in the presence of
arachidonic acid, and production of LTC4 and LTB4
was measured per 106 cells.

Results—Clinical and mucus scores and ΔPplmax
increased during stabling in RAO-affected horses, but
not in control horses. In neutrophils and BALF cells
from both groups, production of LTB4 exceeded that
of LTC4. At all times, LTB4 production by PBNs was
less in RAO-affected horses than it was in control
horses. Before stabling, LTB4 production by cells in
BALF was low in RAO-affected horses, but increased
considerably after 6 hours of stabling. This increase
coincided with the migration of neutrophils into the
airways. In control horses, production of LTB4 did not
change during stabling.

Conclusions and Clinical Relevance—Results suggested
increased production of LTB4 in airways of
RAO-affected horses, compared with control horses,
that may contribute to the infiltration of neutrophils
into the lungs and the sustained inflammation associated
with RAO. ( Am J Vet Res 2004;65:289–295)
Alterations in thyroid hormone concentrations in healthy sled dogs before and after athletic conditioning
Authors: Evason Michelle D. , Carr Anthony P. , Taylor Susan M. , Waldner Cheryl L. 
Published: December 2005

AbstractObjective—To determine effects of athletic conditioning on thyroid hormone concentrations in a population of healthy sled dogs.Animals—19 healthy adult sled dogs.Procedure—Serum concentrations of thyroxine (T4), triiodothyronine (T3), thyroid-stimulating hormone (TSH), free T4(fT4), free T3(fT3), and autoantibodies directed against T3, T4, and thyroglobulin were measured in sled dogs that were not in training (ie, nonracing season) and again after dogs had been training at maximum athletic potential for 4 months.Results—Analysis revealed significant decreases in T4and fT4concentrations and a significant increase in TSH concentration for dogs in the peak training state, compared with concentrations for dogs in the untrained state. Serum concentrations of T4and fT4were less than established reference ranges during the peak training state for 11 of 19 and 8 of 19 dogs, respectively; fT4concentration was greater than the established reference range in 9 of 19 dogs in the untrained state.Conclusions and Clinical Relevance—Decreased total T4and fT4concentrations and increased serum concentrations of TSH were consistently measured during the peak training state in healthy sled dogs, compared with concentrations determined during the untrained state. Although thyroid hormone concentrations remained within the established reference ranges in many of the dogs, values that were outside the reference range in some dogs could potentially lead to an incorrect assessment of thyroid status. Endurance training has a profound impact on the thyroid hormone concentrations of competitive sled dogs. (Am J Vet Res2004;65:333–337)
Effects of xylazine on canine coronary artery vascular rings
Authors: Teng Bunyen , Muir III William W. 
Published: December 2005

AbstractObjective—To determine the effects of xylazine on canine coronary artery smooth muscle tone.Sample Population—Hearts of 26 healthy dogs.Procedure—Dogs were anesthetized with pentobarbital, and vascular rings of various diameters were prepared from the epicardial coronary arteries. Vascular rings were placed in tissue baths to which xylazine was added (cumulative concentrations ranging from 10–10to 10–4M), and changes in vascular ring tension were continuously recorded. Effects of the nitric oxide inhibitor NG-nitro-L-arginine methyl ester (L-NAME; 5mM), the α1-adrenoceptor antagonist prazosin (10mM), and the α2-adrenoceptor antagonist atipamezole (10mM) on xylazine-induced changes in vascular ring tension were determined. Results were expressed as percentage of maximal contraction for each vascular ring preparation.Results—Xylazine induced vasoconstriction of small (< 500-µm-diameter) and medium (500- to 1,000-µmdiameter) vascular rings but not of large (> 1,000-µmdiameter) rings. For large vascular rings, L-NAME, atipamezole, and prazosin did not significantly affect the contractile response to xylazine. For small vascular rings, the contractile response following addition of xylazine to rings treated with L-NAME was not significantly different from the contractile response following addition of xylazine to control rings, except at a xylazine concentration of 10–6M. Xylazine-induced vasoconstriction of small vascular rings was blocked by atipamezole, but the addition of prazosin had no effect on xylazine-induced vasoconstriction.Conclusions and Clinical Relevance—Results suggest that xylazine increases smooth muscle tone of small canine coronary arteriesand that this effect is predominantly mediated by stimulation of α2adrenoceptors.(Am J Vet Res2004;65:431–435)
Sequential measurements of the tibial plateau angle in large-breed, growing dogs
Authors: Odders Jacob W. , Jessen Carl R. , Lipowitz Alan J. 
Published: December 2005

AbstractObjectives—To determine the earliest age that canine tibial plateau angles (TPAs) can be reliably measured and determine whether TPAs change during long bone growth.Animals—10 Labrador Retrievers and 20 Labrador Retriever-hound crossbreeds.Procedure—Stifle joints were radiographed every 2 months from 8 weeks of age to radiographic closure of the tibial physes. Four examiners radiographically evaluated TPA, physeal closure status (ie, complete or incomplete) of the proximal and distal tibial physis, and whether anatomic TPA measurement landmarks were sufficiently visible (LSV) or insufficiently visible (LIV) for accurate measuring. Linear regression analysis was performed to detect change in TPAs over time. Mean ages with 95% confidence intervals (CIs) were determined for dogs with radiographs classified as LIV and LSV.Results—TPAs did not change from 90 days of age to physeal closure. Mean age for dogs with radiographs classified as LIV was 70.2 days (95% CI, 68.12 to 72.28 days), with no dog with LIV radiographs over 81 days of age. Mean age for dogs with radiographs classified as LSV was 85.5 days (CI, 76.73 to 94.27 days).Conclusions and Clinical Relevance—TPAs in Labrador Retrievers and Labrador Retriever-hound crossbreeds can be measured accurately after 90 days of age, and earlier attempts to measure result in falsely low TPA measurements. Measuring TPAs in growing dogs may allow earlier detection of premature physeal closures. As more is learned about the role of the TPA in cranial cruciate ligament injury, early treatment may be possible for growing dogs with cruciate ligament injuries and excessive tibial slope. (Am J Vet Res2004;65:513–518)