bluuebunny/crossref_metadata_2025_split huggingface dataset:
Time course of gastrointestinal tract permeability to chromium 51-labeled ethylenediaminetetraacetate in healthy dogs
Authors: Marks Stanley L. , Williams David A. 
Published: January 2024

Abstract

Objectives
To establish values for gastrointestinal tract permeation by chromium 51-labeled ethylenediaminetetraacetate (51Cr-labeled EDTA) in healthy adult dogs, and to evaluate the time course for 51Cr-labeled EDTA absorption over a 24-hour period after its administration, in an effort to define a shorter, more practical collection method.

Animals
6 healthy adult mixed-breed dogs.

Procedure
After an 18-hour nonfeeding period, each dog was given a solution containing 50 μCi of 51Cr-labeled EDTA in deionized water (10 ml/kg of body weight) by stomach tube. Complete urine collection was done at 2, 4, 6, and 24 hours after 51Cr-labeled EDTA administration. Five-milliliter samples of urine were counted for 15 minutes in a gamma counter, and radioactivity in urine was expressed as a percentage of the orally administered dose.

Results
Median (range) 24-hour urinary recovery of 51Cr-labeled EDTA after 24 hours was 15.1 (12.7 to 20.3)%. Urine collected at 2, 4, and 6 hours contained 1.0 (0.2 to 3.5)%, 6.5 (2.2 to 8.7)%, and 10.0 (8.1 to 11.7)% of the administered 51Cr-labeled EDTA, respectively. Urine passed during the first 6 hours contained, on average, 67 (54 to 77)% of the total 24-hour urine recovery.

Conclusions
6-hour urinary recovery of 51Cr-EDTA provides a potential alternative to 24-hour recovery. This shorter collection period may more specifically reflect small intestinal permeability. (Am J Vet Res 1998; 59:1113-1115)
Role of horn flies (Haematobia irritans) in Staphylococcus aureus-induced mastitis in dairy heifers
Authors: Owens W. E. , Oliver S. P. , Gillespie B. E. , Ray C. H. , Nickerson S. C. 
Published: January 2024

Abstract

Objective
To determine whether Staphylococcus aureus can colonize in horn flies and whether colonization is sufficiently persistent for transmission of the organism to cows by flies.

Animals
2 Jersey heifers exposed to infected horn flies.

Procedure
Staphylococcus aureus was allowed to colonize in horn flies, and duration of colonization was determined. Flies with colonized S aureus were allowed to feed on teats of uninfected heifers to determine whether intramammary infection could be transmitted from fly to heifer. Scab material from naturally infected heifers was submitted for bacteriologic culture to determine whether Saureus was present and whether scabs could serve as a possible source of S aureus for flies.

Results
Staphylococcus aureus colonized in horn flies and remained for up to 96 hours after exposure. Exposure of teats of uninfected heifers to horn flies colonized with S aureus resulted in intrammmary infection in 3 of 4 exposed teats. Culture of scab material from teats of naturally infected heifers revealed high concentration of S aureus (> 107 colony-forming units/mg), and flies without previously colonized S aureus were allowed to feed on scabs; Saureus colonized in them just as readily as it did in flies that had fed on experimentally infected blood.

Conclusions
Horn flies are capable of transmitting Saureus-induced intramammary infection to heifers, and scabs on teats are a potential source of S aureus. Fly control on dairy cows in herds with known Saureus problems is recommended as a method to help prevent these infections. (Am J Vet Res 1998;59: 1122-1124)
Cardiorespiratory and anesthetic effects of propofol and thiopental in dogs
Authors: Quandt Jane E. , Robinson Elaine P. , Rivers William J. , Raffe Marc R. 
Published: January 2024

Abstract

Objective
To compare cardiorespiratory and anesthesia effects of IV administered propofol and thiopental in dogs.

Animals
6 healthy mixed-breed dogs.

Procedure
Each dog was anesthetized with isoflurane, then a thermistor catheter was inserted in the pulmonary artery. After a minimum of 2.5 hours of recovery, a catheter was placed in a cephalic vein for administration of lactated Ringer's solution and drugs. Propofol (8 mg/kg of body weight) or thiopental (19.4 mg/kg) was administered to each dog in a randomized crossover design study. All dogs were intubated and allowed to breathe 100% oxygen spontaneously. Heart rate and rhythm; systolic, diastolic, and mean arterial blood pressures; respiratory rate; end-tidal carbon dioxide concentration; tidal volume; and reflexes (toe web pinch, palpebral response, and jaw tone) were measured before and every 2 minutes for the first 10 minutes, then at 15, 30, and 60 minutes after drug administration. Cardiac output was determined at 0, 2, 6, 10, 15, 30, and 60 minutes, and blood samples were collected at 0, 2, 10, and 30 minutes. Time to endotracheal extubation, head lift, and ability to sit sternally and walk unaided were recorded.

Results
3 of 6 dogs in each group were apneic after drug administration. Reflexes were decreased similarly for both anesthetic agents, but were not completely lost. Time to sternal position and walking unaided were significantly shorter in response to propofol.

Conclusion
Anesthesia was rapid; however, respiratory depression and apnea were major adverse effects associated with propofol and thiopental. Propofol has the advantage of inducing rapid, coordinated anesthesia recovery. (Am J Vet Res 1998;59:1137-1143)
Cloning and expression of porcine recombinant soluble tumor necrosis factor receptor 1
Authors: Boury Nancy Maroushek , Bosworth Brad T. , Stabel Thomas J. , Kehrli Marcus E. , Taylor Michael J. 
Published: January 2024

Abstract

Objective
To clone, sequence, and express porcine recombinant soluble tumor necrosis factor receptor 1 (sTNFR1).

Procedure
A polymerase chain reaction (PCR)-based library enrichment technique was used to isolate a fragment of porcine TNFR1. The mature extracellular domain of porcine TNFR1 was subcloned into an expression vector and expressed in Escherichia coli as a fusion protein. Protein product was purified by immunoaffinity chromatography, using a commercially available affinity gel specific for the marker peptide of the fusion protein. The bioactivity of the purified protein was tested for its ability to inhibit TNF-mediated cytotoxicity in a PK(15) bioassay.

Results
A 927-base pair fragment of porcine TNFR1 encoding the entire extracellular and transmembrane domains, as well as 75 amino acids of the cytoplasmic domain, was isolated from a porcine lung cDNA library. The extracellular domain was expressed as a soluble TNFR1 fusion protein with a yield of 120 to 150 μg/L of culture. Affinity-purified porcine sTNFR1 was able to inhibit TNF-mediated cytotoxicity of porcine PK(15) cells in dose-dependent manner.

Conclusions
Porcine recombinant sTNFR1 inhibits TNF bioactivity in vitro. This recombinant protein will be useful for developing TNFR1 antibodies and studying the roles of TNF and TNFR1 in the pathogenesis of infectious diseases in swine. (Am J Vet Res 1998;59:1317–1322)
Reference values for selected hematologic and biochemical variables in Holstein bulls of various ages
Authors: Monke Donald R. , Kociba Gary J. , DeJarnette Mel , Anderson David E. , Ayars William H. 
Published: January 2024

Abstract

Objective
To determine reference ranges for hematologic and serum biochemical variables of bulls residing at an artificial insemination center.

Animals
225 healthy Holstein bulls categorized by age into yearling, intermediate age, and adult groups.

Procedure
Hematologic and serum biochemical analyses were performed on 1 blood and 1 serum sample from each bull.

Results
Significant differences associated with age were identified for 25 of 33 variables. Serum creatinine concentration for clinically normal adult bulls (2.44 ± 0.33 mg/dl) was higher than previously reported reference values for adult cattle. There was a reversal of the segmented neutrophil-to-lymphocyte ratio between yearling (0.85:1) and adult (2.6:1) bulls. This was associated with a significant and marked decrease in absolute numbers of lymphocytes per microliter between yearling (5,801 ± 1,683) and adult (1,307 ± 509) bulls.

Clinical Relevance
Reference values for selected clinicopathologic variables were generated from the data. (Am J Vet Res 1998;59:1386–1391)
Evaluation of biopsy specimens obtained during thoracoscopy from lungs of clinically normal dogs
Authors: Faunt Karen K. , Jones Brent D. , Turk Jim R. , Cohn Leah A. , Dodam John R. 
Published: January 2024

Abstract

Objective
To determine whether lung biopsy specimens obtained during thoracoscopy, using a commercially available ligature, can provide an adequate amount of tissue for histologic evaluation and to characterize changes in the lungs and thoracic cavity that result from the procedure.

Animals
6 mixed-breed dogs.

Procedure
All dogs underwent 2 anesthetic episodes. The first anesthetic episode was a sham procedure. During the second anesthetic episode, each dog underwent a thoracoscopic procedure to obtain a lung biopsy specimen, using a commercially available ligature. Biopsy specimens were assessed subjectively by means of histologic evaluation. Samples for arterial blood gas analysis were obtained, and thoracic radiography was performed after surgery. Dogs were evaluated daily for 14 days after thoracoscopy and then were euthanatized. Tissues were evaluated grossly and histologically.

Results
Excellent intraoperative visibility and biopsy specimens adequate for histologic evaluation were obtained from all dogs. Significant differences were not found between arterial blood gas values of sham- and thoracoscopy-treated dogs for samples obtained 0.25, 2, and 24 hours after extubation. Examination of thoracic radiographs obtained 2 and 24 hours after thoracoscopy revealed minimal localized pathologic changes. All dogs were clinically normal 24 hours after thoracoscopy, and major postoperative complications were not detected. Gross and histologic findings of specimens obtained during necropsy revealed changes localized to biopsy and trocar sites.

Conclusions
Thoracoscopic placement of ligatures allowed procurement of lung lobe biopsy specimens from clinically normal dogs without complications.

Clinical Relevance
This procedure may provide a safe and minimally invasive means of obtaining lung biopsy specimens from clinically affected dogs. (Am J Vet Res 1998;59:1499–1502)
Technique of, and complications attributable to, repeated hyperosmotic blood-brain barrier disruption in dogs
Authors: Culver Britt , Inzana Karen , Jones Jeryl , Troy Gregory , Kroll Robert , Culver Brenda , Jortner Bernard 
Published: January 2024

Abstract

Objective
To design a repeatable technique for reversible, hyperosmotic blood-brain barrier disruption (BBBD) in dogs and evaluate clinical effects of multiple BBBD.

Animals
10 healthy adult dogs.

Procedure
Using fluoroscopic guidance, an arterial catheter was directed into the internal carotid artery via the femoral artery of 10 dogs. Blood-brain barrier disruption was achieved in 5 dogs, using intracarotid infusion of mannitol. Five control dogs received only saline solution. After recovery, dogs were monitored for clinical signs of disease before a second, nonsurvival procedure was performed 2 to 3 weeks later. BBBD was estimated, using computed tomographic (CT) densitometry values, as well as Evan’s blue dye staining on necropsy specimens.

Results
Seven dogs completed the entire study. Two treatment dogs were lost after the first infusion because of deteriorating neurologic function attributed to CNS edema and increased intracranial pressure. One control dog was lost because of vessel wall damage during catheterization. The remaining dogs had only transient neurologic, ocular, and vasculature injuries. Successful BBBD was documented in all treated dogs by use of CT and Evan’s blue dye evaluation.

Conclusion
Repeated catheterization of the internal carotid artery and disruption of the blood-brain barrier is possible in dogs.

Clinical Relevance
Refinement of this technique would be useful not only for improved delivery of chemotherapeutic agents in patients with brain tumors, but also would allow further investigation of new treatments involving genetically engineered retroviruses and monoclonal antibodies. (Am J Vet Res 1998;59:1503–1510)
Determination of skin concentrations of enrofloxacin in dogs with pyoderma
Authors: DeManuelle T. C. , Ihrke P. J. , Brandt C. M. , Kass P. H. , Vulliet P. R. 
Published: January 2024

Abstract

Objective
To compare serum and skin concentrations of enrofloxacin in dogs with pyoderma with those of clinically normal dogs and to evaluate concentrations in dogs with superficial versus deep pyoderma.

Animals
16 clinically normal dogs and 16 dogs with pyoderma.

Procedure
Enrofloxacin (approx 5 mg/kg of body weight, PO) was administered daily to all dogs. Serum samples and skin biopsy specimens were obtained on day 1 at 3 hours after drug administration and on day 3 immediately before and 3 hours after drug administration. Samples and specimens were assayed by high-performance liquid chromatography. Morphometric analysis was performed on skin biopsy specimens to determine correlation between inflammatory cells and peak tissue enrofloxacin concentration on day 1.

Results
Morphometric analysis revealed high correlation between dermal inflammatory cell count and drug concentration in dogs with pyoderma.

Conclusions
At mean dosage of 5 mg/kg once daily, enrofloxacin tissue concentrations were significantly greater in dogs with pyoderma at 3 hours after pill administration. Enrofloxacin tissue concentration on day 3 at 3 hours after pill administration was 12.4 times the 90% minimum inhibitory concentration of enrofloxacin for Staphylococcus intermedius.

Clinical Relevance
In dogs with pyoderma, therapeutic tissue concentrations of enrofloxacin are reached as early as 3 hours after drug administration. (Am J Vet Res 1998;59:1599-1604)
Effect of timing and route of administration of furosemide on pulmonary hemorrhage and pulmonary arterial pressure in exercising Thoroughbred racehorses
Authors: Lester Guy , Clark Carol , Rice Brett , Steible-Hartless Christine , Vetro-Widenhouse Tamara 
Published: January 2024

Abstract

Objectives
To examine effect of pre-exercise administration of furosemide (FUR) on mean pulmonary arterial pressure (PAP) during work and RBC concentration in bronchoalveolar lavage fluid (BALF) collected 40 minutes after exercise.

Animals
10 adult Thoroughbreds.

Procedure
A modified 10 × 10 crossover design comprising 10 horses during 10 weeks was used. Each horse received each of 5 treatments twice. Treatment structure included a control plus a 2 × 2 factorial and consisted of the following: A, control; B, FUR, 250 mg, IV, 30 minutes before exercise; C, FUR, 250 mg, IV, 240 minutes before exercise; D, FUR, 250 mg, nebulized, 30 minutes before exercise; and E, FUR, 250 mg, nebulized, 240 minutes before exercise. Mean PAP data were collected, and each horse, after a 500-m warm-up, was galloped at maximal speed for 1,600 m. BALF RBC concentration was determined by hemocytometer.

Results
Interaction between treatment method and time of administration was significant (P = 0.04). Treatment B resulted in significantly (P = 0.01) lower BALF RBC concentration than did treatment C. Only BALF RBC count after treatment B was significantly lower than the control value. Horses that received FUR IV had significantly lower peak mean PAP than did those that received the drug by nebulization, regardless of administration time. Only treatment B resulted in peak mean PAP that was significantly lower than that of control. Exercise time was not influenced by treatment.

Conclusions
FUR, administered IV 30 minutes before exercise, significantly reduced peak mean PAP and BALF RBC concentration. (Am J Vet Res 1999; 60:22–28)
Histopathologic alterations induced in the lungs of sheep by use of α2-adrenergic receptor agonists
Authors: Celly Chander S. , Atwal Onkar S. , McDonell Wayne N. , Black William D. 
Published: January 2024

Abstract

Objective
To study effects of central- and peripheral-acting α2-adrenergic receptor agonists on lung parenchyma, platelets, and pulmonary intravascular macrophages (PIM) of sheep.

Animals
12 healthy mature female sheep.

Procedure
Group-1 (control, n = 2) sheep received 5 ml of physiologic saline solution IV and were euthanatized 3 minutes later. Sheep of group 2 (n = 8) received xylazine (150 µg/kg of body weight, IV), then 2 sheep each were euthanatized 3, 10, or 60 minutes, or 12 hours later. Sheep (n = 2) of group 3 were given ST-91 (30 µg/kg, IV), then were euthanatized 3 minutes later. Immediately after euthanasia, the lungs were fixed intratracheally and tissue was obtained for light and electron microscopy after 1 hour.

Results
Pulmonary parenchymal damage or morphologic alterations in PIM and platelets were not evident in control sheep. Three minutes after xylazine administration, morphologic changes in PIM were appreciable. After 10 minutes, extensive damage to the capillary endothelium and alveolar type-I cells, intra-alveolar hemorrhage, and interstitial and alveolar edema were evident. Most PIM had complete internalization of the surface coat. Similar changes were seen 60 minutes after xylazine administration; however, by 12 hours, morphologic features of PIM and lung parenchyma were almost completely restored. Evidence of PIM activation, obvious damage to capillary endothelium, and extensive pulmonary edema also were evident 3 minutes after ST-91 administration.

Conclusions
Xylazine induces severe pulmonary parenchymal damage when administered at clinical sedative doses in sheep; morphologic changes in PIM within 3 minutes after administration of these drugs are substantial; and platelet aggregation is not apparent. (Am J Vet Res 1999;60:154-161)
Shedding of feline immunodeficiency virus in semen of domestic cats during acute infection
Authors: Jordan Holly L. , Liang Yinghua , Hudson Lola C. , Tompkins Wayne A. 
Published: January 2024

Abstract

Objective
To examine shedding of cell-free and cell-associated feline immunodeficiency virus (FIV) in semen of domestic cats during acute infection.

Animals
7 specific-pathogen-free sexually intact male cats.

Procedure
6 cats were inoculated IV with 5 × 106 50% tissue culture infective doses of FIV-NCSU1, and 1 cat served as an uninfected (control) cat. Infection was confirmed in the 6 cats. Periodically for up to 16 weeks after inoculation, cats were anesthetized and ejaculates obtained by use of electroejaculation. Virus was isolated from filtered seminal plasma and washed seminal cells by co-cultivation with a feline CD4+ T-cell line. Seminal cell lysates were also examined for a 582-base pair segment of FIV gag provirus DNA, using a nested polymerase chain reaction amplification.

Results
During the acute phase of FIV infection, virus was evident in semen of 5 inoculated cats. Five cats had virus-positive seminal plasma and 3 had virus-positive cellular constituents during the study. Virus was isolated from 8/22 (36%) seminal plasma samples and 2/17 (18%) seminal cell specimens. Provirus DNA was detected in 5/24 (21%) seminal cell lysates. Cell-free virus was isolated as early as 6 weeks after inoculation, whereas cell-associated virus was isolated as early as 12 weeks after inoculation. Provirus DNA was detected in seminal cells from one cat as early as 1 week after inoculation.

Conclusions and Clinical Relevance
Cell-free and cell-associated FIV are shed in semen of cats early during the course of infection. Samples obtained before seroconversion may contain virus. Virus shedding in ejaculates varies between and within cats during acute infection. (Am J Vet Res 1999;60:211-215.)
Identification and clinical assessment of suspected vaccine-related field strains of porcine reproductive and respiratory syndrome virus
Authors: Mengeling William L. , Vorwald Ann C. , Lager Kelly M. , Clouser Deborah F. , Wesley Ronald D. 
Published: January 2024

Abstract

Objective
To determine the origin and clinical relevance of selected strains of porcine reproductive and respiratory syndrome (PARS) virus (PRRSV).

Animals
38 pigs without antibodies for PRRSV.

Procedure
A seemingly uncommon restriction endonuclease digestion site in a commercially available vaccine strain of attenuated PRRSV was tested for its stability and prevalence under defined conditions. Selected field strains of PRRSV, with or without the restriction-site marker, were subsequently tested in pigs for virulence and for their ability to replicate competitively in pigs simultaneously given the vaccine.

Results
Under experimental conditions, the restriction-site marker was stable during long-term infection of pigs. It was not detected in any of the 25 field strains of PRRSV that were isolated before use of the vaccine or 21 of 25 field strains that were isolated after use of the vaccine but that, on the basis of previous testing, were believed unrelated to the vaccine strain. Conversely, it was detected in 24 of 25 field strains that were isolated after use of the vaccine and that, on the basis of previous testing, were believed to be direct-line descendants of the vaccine strain. Putative vaccine-related strains caused more pronounced pathologic changes than did the vaccine strain alone, and they predominated during replication in pigs also given the vaccine strain.

Conclusions
In some swine herds, the vaccine strain may have persisted and mutated to a less attenuated form.

Clinical Relevance
The potential for persistence and mutation of specific strains of virus should be an important consideration when designing vaccination programs involving attenuated PRRSV. (Am J Vet Res 1999;60:334–340)
Polymerase chain reaction techniques for differentiating cytotoxic and noncytotoxic Pasteurella trehalosi from Rocky Mountain bighorn sheep
Authors: Green Alice L. , DuTeau Nancy M. , Miller Michael W. , Triantis Joni M. , Salman M. D. 
Published: January 2024

Abstract

Objective
To evaluate 2 polymerase chain reaction (PCR)-based methods for differentiating cytotoxic and noncytotoxic Pasteurella trehalosi from Rocky Mountain bighorn sheep (Ovis canadensis canadensis).

Sample Population
23 isolates of P trehalosi from bighorn sheep in Colorado, including 18 from free-ranging herds and 5 from a captive herd.

Procedure
Using a sequence of the leukotoxin gene region of P haemolytica serotype 1, 7 PCR primers were designed. A PCR amplification was performed on a sample of bacterial cell suspensions from pure cultures of P trehalosi with known in vitro cytotoxic effects. The 2 most promising primer pairs were used in a study of 23 P trehalosi isolates. Results were analyzed for association with cytotoxicity and 3 distinct ribotypes (ECO, ACO, and BCO).

Results
Significant associations were observed between in vitro cytotoxicity and PCR results for coding region, between ribotype ECO classification and PCR results for coding region, and between ribotype ECO classification and PCR results for promoter region. There was a negative association between ribotype ACO classification and PCR results for coding and promoter regions.

Conclusions and Clinical Relevance
The PCR for the leukotoxin A coding region may be useful in differentiating cytotoxic from noncytotoxic P trehalosi isolates recovered from bighorn sheep. It may be useful for studying epidemiologic features of pasteurellosis in bighorn sheep and for designing vaccines to protect wild sheep against pneumonia caused by P trehalosi and P haemolytica. (Am J Vet Res 1999;60:583–588)