bluuebunny/crossref_metadata_2025 huggingface dataset:
Postexposure prophylaxis for prevention of rabies in dogs
Authors: Hanlon Cathleen A. , Niezgoda Michael , Rupprecht Charles E.
Published: December 2005

Objective—To evaluate postexposure prophylaxis (PEP) in dogs experimentally infected with rabies.

Procedure—29 Beagles.

Procedure—Dogs were sedated and inoculated in the right masseter muscle with a salivary gland homogenate from a naturally infected rabid dog (day 0). Six hours later, 5 dogs were treated by administration of 2 murine anti-rabies glycoprotein monoclonal antibodies (mAb) and commercial vaccine; 5 received mAb alone; 5 received purified, heat-treated, equine rabies immune globulin (PHT-ERIG) and vaccine; 5 received PHT-ERIG alone; 4 received vaccine alone; and 5 control dogs were not treated. The mAb or PHTERIG was administered at the site of rabies virus inoculation. Additional vaccine doses for groups mAb plus vaccine, PHT-ERIG plus vaccine, and vaccine alone were administered IM in the right hind limb on days 3, 7, 14, and 35.

Results—All control dogs and dogs that received only vaccine developed rabies. In the PHT-ERIG and vaccine group, 2 of 5 dogs were protected, whereas none were protected with PHT-ERIG alone. Use of mAb alone resulted in protection in 4 of 5 dogs. Administration of mAb in combination with vaccine provided protection in all 5 dogs.

Conclusions and Clinical Relevance—Current national guidelines recommend euthanasia or a 6- month quarantine for unvaccinated animals exposed to rabies. Findings from this study document that vaccine alone following severe exposure was unable to provide protection from rabies. However, vaccine combined with mAb resulted in protection in all treated dogs, revealing the potential use of mAb in PEP against rabies in naïve dogs. (Am J Vet Res2002;63:1096–1100)
Serum concentrations of keratan sulfate, osteocalcin, and pyridinoline crosslinks after oral administration of glucosamine to Standardbred horses during race training
Authors: Caron John P. , Peters Tonia L. , Hauptman Joseph G. , Eberhart Susan W. , Orth Michael W.
Published: December 2005

Objective—To determine the effects of orally administered glucosamine on concentrations of markers of bone and cartilage metabolism in Standardbred horses during race training.

Animals—Twenty 16- to 20-month-old Standardbreds beginning race training.

Procedure—Horses were randomly assigned to 2 groups. One group received glucosamine hydrochloride (4 g, PO, q 12 h), and the second (control) group received glucose (4 g, PO, q 12 h). Serum samples were obtained prior to onset of the study (baseline) and at regular intervals for 48 weeks for determination of concentrations of keratan sulfate (KS), osteocalcin (OC), and pyridinoline crosslinks (PYD).

Results—Osteocalcin concentrations changed significantly with time; mean serum concentrations were significantly higher than baseline values for samples obtained at 24 to 48 weeks after onset of the study. Although a significant effect of time was observed for mean concentration of KS, concentrations did not differ significantly from baseline values at any time during the study when groups were analyzed separately. However, pooled analysis revealed significant increases of mean serum KS concentration at weeks 24 and 30. Significant changes in serum PYD concentrations were not detected. Oral administration of glucosamine did not significantly affect serum concentrations of any of the markers.

Conclusions and Clinical Relevance—Increased serum OC in clinically normal Standardbreds during race training may reflect bone formation that accompanies adaptive remodeling of the appendicular skeleton. For these experimental conditions, glucosamine did not appear to exert a detectable influence on serum concentrations of these 3 markers of connective tissue metabolism. (Am J Vet Res2002;63:1106–1110)
Relationship of vitamin E supplementation and antimicrobial treatment with acute-phase protein responses in cattle affected by naturally acquired respiratory tract disease
Authors: Carter Jeffrey N. , Meredith Glacia L. , Montelongo Marie , Gill Donald R. , Krehbiel Clinton R. , Payton Mark E. , Confer Anthony W.
Published: December 2005

Objective—To correlate serum concentrations of fibrinogen (Fib), haptoglobin (Hap), serum amyloid-A (SAA), and α-1 acid glycoprotein (AGP) with clinical respiratory tract disease and response to treatment in transport-stressed feedlot cattle fed vitamin E-supplemented diets.

Animals—387 heifer calves (mean initial weight, 197 kg).

Procedure—Calves purchased from an order buyer were delivered to a feedlot to study the effects of dietary supplementation with 2,000 IU of vitamin E for 0, 7, 14, or 28 days after arrival. Serum or plasma Fib, Hap, SAA, and AGP concentrations were measured on days 0, 7, and 28 after arrival as well as at the time of treatment for respiratory tract disease with antimicrobial drugs and after completion of treatment.

Results—Vitamin E supplementation was associated with decreased treatment costs. In cattle that were not recognized as sick or responded positively to 1 antimicrobial treatment, serum Hap concentrations were significantly lower on days 0 and 7 than concentrations for cattle that required > 1 treatment. Serum Hap concentrations and ratios of Hap to SAA on day 0 significantly correlated with the number of antimicrobial treatments required. Serum Hap concentrations at the time of initial treatment were significantly lower for cattle that required only 1 treatment, compared with those that required > 1 treatment.

Conclusions and Clinical Relevance—Serum Hap concentrations are of potential value for use in assessing feedlot cattle that may become ill as a result of respiratory tract disease and for use in monitoring treatment efficacy. (Am J Vet Res2002; 63:1111–1117)
In vivo and in vitro comparisons of spray-drying and solvent-evaporation preparation of microencapsulated Mycoplasma hyopneumoniae for use as an orally administered vaccine for pigs
Authors: Lin J. H. , Pan M. J. , Liao C. W. , Weng C. N.
Published: December 2005

Objective—To evaluate the efficacy of an orally administered vaccine ofMycoplasma hyopneumoniaethat was prepared by spray drying or solvent evaporation.

Animals—Thirty 6-week-old, crossbred, specificpathogen- free (SPF) pigs.

Procedure—Pigs were randomly allocated into 5 groups and housed in an SPF facility. Pigs in 2 groups (groups AQ and CAP) were fedM hyopneumoniaeenteric-coated vaccine on days 0, 10, and 20. A third group (group IM) received an IM injection ofM hyopneumoniaevaccine with aluminium hydroxide as an adjuvant on days 0, 10, and 20. The last 2 groups (nonvaccinated- challenged [NV-C] and nonchallenged [NC]) were fed a sham treatment. All 24 pigs in groups AQ, CAP, IM, and NV-C were challenge exposed with 5 ml of a 10% pneumonic lung suspension administered on day 40 via intubation of the trachea. All pigs were slaughtered and the lungs removed and examined for lesions on day 68.

Results—In vitro studies indicated that these 2 microencapsulation techniques formed an effective shell and protected mycoplasmal antigen from gastric acid. Results of inoculation and challenge tests indicated that microencapsulatedM hyopneumoniaewere sufficiently potent to induce an immune response and provide good protection.

Conclusions and Clinical Relevance—Orally administered microencapsulatedM hyopneumoniaevaccines induced an immune response and reduced the severity of lung lesions in challengeexposed pigs. Results suggest that this novel method can be applied to other antigens, because the spray-drying process yielded an orally administeredM hyopneumoniaevaccine that induced a good immune response. (Am J Vet Res2002; 63:1118–1123)
Effect of genistein on replication of bovine herpesvirus type 1
Authors: Akula Shaw M. , Hurley David J. , Wixon Regina L. , Wang Chungyang , Chase Christopher C. L.
Published: December 2005

Objective—To study the antiviral activity of genistein, a soya isoflavone, on in vitro replication of bovine herpesvirus type 1 (BHV-1).

Sample Population—Madin-Darby bovine kidney (MDBK) cells.

Procedure—Effects of genistein on the magnitude and kinetics of inhibition of BHV-1 phosphorylation of glycoprotein E (gE) and in vitro replication of BHV-1 in MDBK cells were evaluated. Antiviral activity of genistein was compared with 2 compounds, estradiol-17β (EST) and tamoxifen (TAM), that have estrogenic and antiestrogenic activity, respectively. High-performance liquid chromatography (HPLC) was used to determine the concentration of genistein in medium from infected and uninfected MDBK cultures.

Results—Genistein reduced BHV-1, but not gE-deleted BHV-1 (BHV-1gEΔ3.1), replication by 90% at 18 hours after inoculation. This inhibition was not sustained through 24 hours after inoculation. The genistein concentration in media from MDBK cells was decreased by 40% during BHV-1 infection, compared with 16% for uninfected cells, at 24 hours after inoculation. Genistein inhibited gE phosphorylation and BHV- 1 replication in a dose-dependent manner. Dosing with 25 µMgenistein at 0 and 12 hours after inoculation of BHV-1 was optimal for decreasing BHV-1 replication. Estradiol-17β EST and TAM did not affect BHV-1 replication.

Conclusions and Clinical Relevance—The decrease in genistein concentration was a viral infection-dependent event. Genistein is an inhibitor of BHV-1 replication because of its ability to inhibit tyrosine kinase activity. A possible application may be for the control of BHV-1 infection in cattle by feeding soya products rich in genistein prior to or during periods of stress. (Am J Vet Res2002;63:1124–1128)
Activating mutations in the catalytic or juxtamembrane domain of c- kit in splenic mast cell tumors of cats
Authors: Dank Gillians , Chien May B. , London Cheryl A.
Published: December 2005

Objective—To evaluate splenic mast cell tumors (MCT) of cats for activating mutations in the protooncogene c-kit.

Sample Population—10 formalin-fixed, paraffinembedded splenic MCT from cats in the pathology database of the Veterinary Medical Teaching Hospital at the University of California, Davis.

Procedure—Genomic DNA was isolated from tumor specimens, and the polymerase chain reaction (PCR) procedure was performed for exons 11, 12, and 17. The PCR products were analyzed by use of agarose gel electrophoresis and then directly sequenced.

Results—We did not identify mutations in the juxtamembrane domain (encoded by exons 11 and 12) or catalytic domain (encoded by exon 17) of c-kitin any of the splenic MCT specimens.

Conclusions and Clinical Relevance—Although mutations in the proto-oncogene c-kitoccur frequently in naturally developing MCT in dogs and aggressive mastocytosis in humans, the data reported here documented that dysregulation of Kit function through activating mutations is unlikely in splenic MCT of cats. Therapeutic strategies aimed at inhibiting Kit signaling (ie, kinase inhibitors such as imatinib [STI571]) may not be of benefit for the treatment of this disease in cats. (Am J Vet Res2002;63:1129–1133).
Effects of anti-arthritis preparations on gene expression and enzyme activity of cyclooxygenase-2 in cultured equine chondrocytes
Authors: Tung Jayne T. , Venta Patrick J. , Eberhart Susan W. , Yuzbasiyan-Gurkan Vilma , Alexander Lee , Caron John P.
Published: December 2005

Objective—To determine the effects of recombinant equine interleukin -1β (reIL-1β) and 4 anti-inflammatory compounds on the expression and activity of cyclooxygenase (COX)-2 in cultured equine chondrocytes.

Sample Population—Articular cartilage from 9 young adult horses.

Procedure—Reverse transcriptase-polymerase chain reaction methods were used to amplify a portion of equine COX-2 to prepare a cDNA probe. Northern blot analysis was used to quantify the expression of COX-2 in first-passage cultures of equine articular chondrocytes propagated in media containing dexamethasone (DEX), phenylbutazone (PBZ), polysulfated glycosaminoglycan, and hyaluronan, each at concentrations of 10 and 100 µg/ml and each with or without reIL-1β. A commercial immunoassay was used to determine prostaglandin E2(PGE2) concentrations in conditioned medium of similarly treated cells to quantify COX-2 activity.

Results—Addition of reIL-1β increased the expression of COX-2 in a dose-dependent manner, which was paralleled by an increased concentration of PGE2in culture medium. Concentration of PGE2in spent medium from reIL-1β-treated chondrocytes was significantly reduced by DEX and PBZ; however, only DEX significantly reduced gene expression of COX-2.

Conclusions and Clinical Relevance—Prostaglandin E2is considered to be an important mediator in the pathophysiologic processes of arthritis, and cultured chondrocytes respond to interleukin-1 with enhanced expression and activity of COX-2. Palliative relief in affected horses is probably attributable, in part, to inhibition of PGE2synthesis; however, analysis of these data suggests that of the 4 compounds tested, only DEX affects pretranslational regulation of the COX-2 gene in cultured equine chondrocytes. (Am J Vet Res2002;63:1134–1139)
Effect of prolonged water immersion on equine hoof epidermis in vitro
Authors: Wagner Ilka P. , Hood David M.
Published: December 2005

Objective—To evaluate the effect of prolonged water exposure on tissue mass and solutes of outer and inner layers of the stratum medium, sole, frog, and the stratum medium (SMZA) zona alba layer of horses' hooves.

Specimen Population—10 hooves from 10 horses without foot abnormalities.

Procedure—Hoof wall tissue specimens were obtained and immersed for 10 days in distilled deionized water. Serial changes in mass were recorded during the immersion period. Subsequently, osmolarity and Na+, K+, Cl–, and protein concentrations of the immersion solution were quantified.

Results—Fully cornified outer hoof wall, sole, and frog epidermal structures increased in mass, whereas the SMZA lost mass when immersed in water. All hoof structures had a variable loss of crystalloids during immersion, but none of the specimens lost proteins. The frog epidermis was distinct in that total solute lost during immersion could not be ascribed to Na+, K+, and Cl–.

Conclusions and Clinical Relevance—Data support a 2-compartment model for the fully cornified outer stratum medium, frog, and sole that permits the exchange of crystalloids, but not proteins, across the cell membrane and infers that topical agents containing proteins cannot benefit the hoof. The unique osmotic behavior of the SMZA relative to other hoof structures suggests the hypothesis that it is composed of transitional epithelial cells. The solutes lost from frog epithelium are interpreted to reflect its unique lipid composition. (Am J Vet Res2002;63:1140–1144)
Hematologic and serum biochemical changes in Salmonella ser Typhimurium-infected calves
Authors: Santos Renato L. , Tsolis Renée M. , Bäumler Andreas J. , Adams L. Garry
Published: December 2005

Objective—To evaluate hematologic and serum biochemical changes inSalmonellaser Typhimurium infected calves.

Animals—16 male 3- to 4-week-old dairy calves.

Procedure—13 calves were experimentally infected withSTyphimurium (strains IR715 and CS401, which are derivatives of ATCC 14028), and 3 calves were uninfected controls. Several hematologic and serum biochemical parameters were measured.

Results—Hematologic changes included increases in PCV, RBC count, and hemoglobin concentration, associated with a transitory leukopenia characterized by neutropenia and lymphopenia. Biochemical findings included hypoglycemia, increased BUN, creatinine, and fibrinogen concentrations, and decreased sodium, total CO2, calcium, total protein, and albumin concentrations. Increased total bilirubin concentration associated with decreased conjugated bilirubin concentration was also observed. No significant changes in aspartate aminotransferase, γ-glutamyltranspeptidase, alkaline phosphatase, and creatinine kinase activities were detecte

Conclusions and Clinical Relevance—Experimental salmonellosis of calves results in marked to severe dehydration, accompanied by metabolic acidosis, hypoglycemia, and an acute inflammatory response associated with increased fibrinogen concentrations and severe neutropenia immediately after inoculation. (Am J Vet Res2002;63:1145–1150)
Computed tomographic osteoabsorptiometry of the elbow joint in clinically normal dogs
Authors: Samii Valerie F. , Les Clifford M. , Schulz Kurt S. , Keyak Joyce H. , Stover Susan M.
Published: December 2005

Objective—To evaluate subchondral bone density patterns in elbow joints of clinically normal dogs by use of computed tomographic (CT) osteoabsorptiometry.

Sample Population—20 cadaver forelimbs from 10 clinically normal dogs.

Procedure—Each elbow joint was imaged in parasagittal and transverse planes of 1.5-mm thickness. Slice data were converted to dipotassium phosphate equivalent density (PPED) values. Sagittal, parasagittal, and transverse medial coronoid process topographic maps were constructed. Defined zones were created for each of the 3 CT planes, and confluence and peak PPED values were determined.

Results—The lowest PPED value was 340 mg/ml (articular and subchondral confluence), and the highest was 1780 mg/ml (peak subchondral density). Detectable effects of joint laterality were not found in the confluence or peak PPED measurements or in the peak-to-confluence PPED ratio for all 3 CT planes. Significant differences were found among zones in all 3 planes for confluence and peak PPED measurements and between sagittal and transverse planes for peak-to-confluence PPED ratios. Subjectively, the pattern of density distribution among dogs was fairly consistent for the sagittal and parasagittal slices. Three specific patterns of density distribution were apparent on the transverse topographic maps of the medial coronoid process that corresponded to conformational differences.

Conclusions and Clinical Relevance—The use of CT osteoabsorptiometry provides a repeatable technique that can be used to noninvasively examine bone density and the effects of stress acting on joints in vivo. Variability in density values for any of the CT planes was not identified among clinically normal dogs. (Am J Vet Ress 2002;63:1159–1166
Effect of preexisting FeLV infection or FeLV and feline immunodeficiency virus coinfection on pathogenicity of the small variant of Haemobartonella felis in cats
Authors: George Jeanne W. , Rideout Bruce A. , Griffey Stephen M. , Pedersen Niels C.
Published: December 2005

Objective—To investigate the effects of preexisting FeLV infection or FeLV and feline immunodeficiency (FIV) coinfection on the pathogenicity of the small variant ofHaemobartonella felis(Hfsm, California variant) in cats.

Animals—20 FeLV infected, 5 FeLV-FIV coinfected, and 19 retrovirus-free cats.

Procedure—A client-owned cat, coinfected with FeLV and Hfsm, was the source for Hfsm. Inoculum 1 (FeLV free) was obtained by passage of source Hfsm through 4 FeLV-resistant cats. Inoculum 2 was obtained by further passage of Hfsm (inoculum 1) through 2 specific pathogenfree cats.

Results—A mild-to-moderate anemia started 21 days after inoculation, with its nadir occurring at 35 to 42 days after inoculation. Infection with Hfsm induced greater decrease in hemoglobin concentration in FeLV infected cats, compared with retrovirus free cats. Reticulocytosis, macrocytosis, and polychromasia of erythrocytes developed in anemic cats regardless of retrovirus infection status. Mean neutrophil counts decreased during the hemolytic episode. For most cats, the anemia was transient. Four FeLV infected cats, 1 of which was also FIV infected, developed fatal FeLV-associated myeloproliferative diseases. Of the surviving cats, 8 died over the next 24 months from other FeLV-related diseases. Hemolysis did not recur after the initial episode. Inoculum 1 induced more severe anemia than inoculum 2.

Conclusions and Clinical Relevance—Our results support the clinical observation that cats coinfected with FeLV and H felis develop more severe anemia than cats infected with H felis alone. Infection with Hfsm may induce myeloproliferative disease in FeLV infected cats. The small variant of H felis may lose pathogenicity by passage through FeLV-free cats. (Am J Vet Res2002;63:1172–1178)
Effect of infection with bovine viral diarrhea virus alone, bovine rotavirus alone, or concurrent infection with both on enteric disease in gnotobiotic neonatal calves
Authors: Kelling Clayton L. , Steffen David J. , Cooper Vickie L. , Higuchi Deborrah S. , Eskridge Kent M.
Published: December 2005

Objective—To compare experimentally induced concurrent infection with bovine viral diarrhea virus (BVDV) and bovine rotavirus (BRV) with infection of either virus alone in calves.

Animals—Seventeen 1-day-old gnotobiotic calves.

Procedure—Calves were allotted to 8 treatments as follows: group 1, mock-infected control calves (n = 2); group 2, inoculated with BVDV on day 1 (2); groups 3, 5, and 7, inoculated with BRV on days 1 (2), 4 (1), or 7 (2), respectively; and groups 4, 6, and 8, inoculated with BVDV on day 1 and with BRV on days 1 (2), 4 (2), or 7 (4), respectively. Concentrations of BVDV in serum and ileal tissues were measured, and BRV shedding in feces was determined. Histologic examination and immunohistochemical analysis were conducted to detect lesions and viral antigens.

Results—Neonatal calves inoculated with BVDV alone or with BVDV on day 1 and BRV on day 7 developed villus atrophy and submucosal inflammation of the intestines. Concurrent BVDV and BRV infections acted synergistically in the intestinal tract, causing more severe enteric disease than infection with either virus alone. Severe lymphoid depletion was associated with BVDV infection in calves regardlesss of concurrent BRV infection.

Conclusions and Clinical Relevance—Infection with BVDV played direct and indirect roles in enteritis in neonatal calves, causing villus atrophy in the duodenum and submucosal inflammation of the intestines. Also, BVDV potentiated effects of BRV. Concurrent infection with BVDV and BRV resulted in more severe enteric disease in neonatal calves than infection with BRV or BVDV alone. (Am J Vet Res2002;63:1179–1186)
Effects of morphine, butorphanol, buprenorphine, and U50488H on the minimum alveolar concentration of isoflurane in cats
Authors: Ilkiw Jan E. , Pascoe Peter J. , Tripp Linda D.
Published: December 2005

Objective—To determine whether opioids with varying interactions at receptors induce a reduction in minimum alveolar concentration (MAC) of isoflurane in cats.

Animals—12 healthy, female, spayed cats.

Procedure—Cats were anesthetized with isoflurane and instrumented to allow collection of arterial blood and measurement of arterial blood pressure. Each drug was studied separately, and for each drug cats were randomly allocated to receive 2 doses. The drugs studied were morphine (0.1 or 1.0 mg/kg), butorphanol (0.08 or 0.8 mg/kg), buprenorphine (0.005 and 0.05 mg/kg), and U50488H (0.02 and 0.2 mg/kg). All drugs were diluted in 5 ml of saline (0.9% NaCl) solution and infused IV for 5 minutes. The MAC of isoflurane was determined in triplicate, the drug administered, and the MAC of isoflurane redetermined for a period of 3 hours.

Results—All drugs had a significant effect on MAC over time. With morphine only, the effect on MAC over time was different between doses. The greatest mean (± SD) reductions in MAC of isoflurane in response to morphine, butorphanol, buprenorphine, and U50488H administration were 28 ± 9, 19 ± 3, 14 ± 7, and 11 ± 7%, respectively.

Conclusions and Clinical Relevance—Morphine (1.0 mg/kg) and butorphanol (0.08 and 0.8 mg/kg) induced significant reductions in MAC of isoflurane that were considered clinically important. Although significant, reductions in MAC of isoflurane induced by morphine (0.1 mg/kg), buprenorphine (0.005 and 0.05 mg/kg), and U50488H (0.02 and 0.2 mg/kg) were not considered clinically relevant because they fell within the error of the measurement technique. Administration of morphine or butorphanol decreases the need for potent inhalant anesthetics in cats and could potentially be beneficial in combination with inhalants. (Am J Vet Res2002;63:1198–1202)
Use of plasma clearance of technetium Tc 99m pentetate to estimate renal clearance during postnatal development in pigs
Authors: Eskild-Jensen Anni , Rehling Michael , Nielsen Asker S. , Nielsen Lene E. , Frøkiær Jørgen
Published: December 2005

Objective—To compare renal clearance of technetium
Tc 99m pentetate with plasma clearance by
use of a glomerular filtration rate technique in pigs
from 3 to 24 weeks of age.

Animals—24 female pigs.

Procedure—At the time of investigation, 5 pigs were
3 weeks old, 6 pigs were 6 weeks old, 8 pigs were 12
weeks old, and 5 pigs were 24 weeks old. Plasma
clearance of technetium Tc 99m pentetate was measured
by the use of a single injection technique followed
by collection of multiple blood samples until 5
hours after the injection. Simultaneously, urine was
collected through a urinary catheter, and the renal
clearance of technetium Tc 99m pentetate was calculated.

Results—Plasma clearance of technetium Tc 99m
pentetate was correlated with the renal clearance
( r = 0.95). Plasma clearance was higher than renal
clearance at all ages (mean, 5.8%), indicating
extrarenal clearance of technetium Tc 99m pentetate
or methodologic errors. Volume of distribution
increased with increasing age but decreased as a
fraction of body weight.

Conclusions—Plasma clearance of technetium Tc
99m pentetate estimates renal clearance with acceptable
precision when using single injection technique
and multiple blood samples in pigs from 3 to 24
weeks of age. (Am J Vet Res 2002;63:1203–1206)
Effect of intrathecal and intravenous administration of oxytocin on amplitude of the reflex-evoked muscle action potential after electrical stimulation of the tooth pulp in anesthetized dogs
Authors: Brown Dorothy C. , Bernier Noemie , Shofer Frances , Steinberg Sheldon A. , Perkowski Sandra Z.
Published: December 2005

Objective—To determine whether intrathecal (IT) or IV administration of oxytocin will diminish amplitude of the reflex-evoked muscle action potential (REMP) in the digastricus muscle during electrical stimulation of the tooth pulp in anesthetized dogs, thus suggesting an analgesic effect for oxytocin.

Animals—6 male Beagles that were 2 to 6 years old.

Procedure—Dogs were used in a crossover design with at least a 5-day washout period between treatments. Each dog received morphine, saline (0.9% NaCl) solution, and oxytocin by both the IT and IV routes of administration. Noninvasive dental dolorimetry was used to assess changes in pain threshold following administration of treatments. Effectiveness of analgesia was determined on the basis of change in REMP amplitude in the digastricus muscle.

Results—Morphine administered IV significantly inhibited REMP amplitude, compared with IV administration of saline solution or oxytocin. There was not a significant change in REMP amplitude between saline solution and oxytocin administered IV. Intrathecal administration of morphine significantly inhibited REMP amplitude, compared with IT administration of saline solution or oxytocin. Intrathecal administration of oxytocin significantly increased REMP amplitude, compared with IT administration of saline solution or morphine.

Conclusions and Clinical Relevance—Although IV administration of oxytocin did not have an effect on REMP amplitude, compared with IV administration of saline solution, IT administration of oxytocin had the opposite effect of morphine and increased REMP amplitude of the digastricus muscle. These data do not support the use of oxytocin as an analgesic agent in dogs. (Am J Vet Res2002;63:1354–1358)
Characterization of matrix metalloproteinase-2 and -9 in cerebrospinal fluid of clinically normal dogs
Authors: Bergman Robert L. , Inzana Karen D. , Inzana Thomas J.
Published: December 2005

Objective—To characterize matrix metalloproteinase (MMP)-2 and -9 in CSF of clinically normal dogs.

Sample Population—Samples of CSF collected from 23 dogs.

Procedure—Dogs were anesthetized, CSF samples were collected, and dogs were then euthanatized. Each CSF sample was evaluated immediately for RBC count, WBC count, and protein and glucose concentrations, and cytologic examination also was performed. Samples were considered normal when protein concentration was < 25 mg/dL and CSF contained < 6 WBCs/μL and < 25 RBCs/μL. Samples were stored at –70°C. Sections of brain tissue were collected and processed for histologic examination. The MMPs were evaluated by use of gelatin zymography and a polyclonal antibody-based sandwich ELISA.

Results—Mean WBC count for CSF samples was < 1 WBC/μL (range, 0 to 3 WBCs/mL). Mean protein concentration was 12 mg/dL (range, 8 to 17 mg/dL). Mean RBC count was 3.65 RBCs/μL (range, 0 to 21 RBCs/μL). All CSF samples generated a clear band on zymography gels that corresponded to the human commercial standard of proenzyme MMP-2. Other major clear bands were not detected on zymography gels. Bands correlating to MMP-9 were not detected in any samples. The ELISA results revealed a mean ± SD proenzyme MMP-2 concentration of 5.61 ± 1.92 ng/mL (range, 3.36 to 10.83 ng/mL).

Conclusions and Clinical Relevance—The proenzyme form of MMP-2 is detectable in CSF of clinically normal dogs, whereas MMP-9 is not detectable. Additional investigation of MMPs in CSF from dogs with various diseases of the nervous system is indicated. (Am J Vet Res2002;63:1359–1362)
Effects of carprofen and dexamethasone on canine chondrocytes in a three-dimensional culture model of osteoarthritis
Authors: Dvorak Laura D. , Cook James L. , Kreeger John M. , Kuroki Keiichi , Tomlinson James L.
Published: December 2005

Objective—To determine effects of carprofen and dexamethasone on chondrocytes in a culture model of osteoarthritis (OA).

Sample Population—Chondrocytes isolated from articular cartilage of the humeral head of 5 adult dogs.

Procedure—Chondrocytes were harvested, cultured and subcultured in monolayer, and then cultured in a 3-dimensional (3-D) medium. Cells from each dog were distributed into 6 groups with differing content of liquid medium for each 3-D construct (agarose [AG], AG plus interleukin [IL]-1β, AG plus carprofen [4 μg/mL], AG plus dexamethasone [1 mg/mL], AG plus IL-1β [20 ng/mL] plus carprofen [4 μg/mL], and AG plus IL-1β (20 ng/mL) plus dexamethasone (1 mg/mL). On days 3, 6, 12, and 20 of culture, samples from all groups were collected. Liquid media were assayed for glycosaminoglycan, prostaglandin (PG)E2, matrix metalloprotease (MMP)-3, and MMP- 13 concentrations. All 3-D constructs were evaluated for viability, cell morphology, proteoglycan staining, and collagen type-II concentration. Total glycosaminoglycan content in each 3-D construct was quantitated by spectrophotometric assay.

Results—Addition of IL-1β caused a significant loss of cell viability and matrix production. Addition of carprofen or dexamethasone caused significant decreases in PGE2 in the liquid media, and each was minimally effective in protecting chondrocytes against negative effects of IL-1β.

Conclusions and Clinical Relevance—Human recombinant IL-1β resulted in loss of cell viability, alterations in extracellular matrix components, and production of PG and MMP. Carprofen and dexamethasone had little effect on cell and matrix variables but did decrease PGE2 concentrations and primarily affected the inflammatory pathway of osteoarthritis. (Am J Vet Res2002;63:1363–1369)
Effect of administration of a phospholipid emulsion on the initial response of horses administered endotoxin
Authors: Winchell Wyatt W. , Hardy Joanne , Levine Daniel M. , Parker Thomas S. , Gordon Bruce R. , Saal Stuart D.
Published: December 2005

Objective—To evaluate the effect of a phospholipid emulsion (PLE) on the initial response of horses to administration of endotoxin.

Animals—12 healthy adult horses.

Procedures—Horses were assigned to 2 treatment groups (6 horses/group). The control group was administered 1 L of saline (0.9% NaCl) solution, and the treated group was administered PLE (200 mg/kg, IV); treatments were administered during a period of 120 minutes. An infusion of endotoxin was initiated in both groups starting 1 hour after initiation of the saline or PLE solutions. Physical examination and hemodynamic variables were recorded, and blood samples were analyzed for concentrations of tumor necrosis factor (TNF)-α, interleukin-6, thromboxane B2 (TxB2), 6 keto-prostaglandin F (PGF)1α, total leukocyte count, and PLE concentrations. An ANOVA was used to detect significant differences.

Results—Administration of PLE resulted in significantly lower rectal temperature, heart rate, cardiac output, right atrial pressure, and pulmonary artery pressure and higher total leukocyte counts in treated horses, compared with values for control horses. The TNF-α concentration was significantly less in treated horses than in control horses. The TxB2 and 6 keto- PGF1α concentrations were significantly different between treated and control horses at 30 minutes (TxB2) and at 30 and 60 minutes (6 keto-PGF1α).

Conclusions and Clinical Relevance—Prior infusion of PLE in horses administered a low dose of endotoxin decreased rectal temperature, heart rate, pulmonary artery pressure, and TNF-α concentrations. Results of this study support further evaluation of PLE for use in the treatment of horses with endotoxemia. (Am J Vet Res2002;63:1370–1378)
Comparative virulence of isolates of bovine viral diarrhea virus type II in experimentally inoculated six- to nine-month-old calves
Authors: Kelling Clayton L. , Steffen David J. , Topliff Christina L. , Eskridge Kent M. , Donis Ruben O. , Higuchi Deborrah S.
Published: December 2005

Objective—To determine the comparative virulence of 5 isolates of bovine viral diarrhea virus (BVDV) type II by inoculating 6- to 9-month-old beef calves with isolates originating from the tissues of cattle affected with naturally occurring, transient, acute, nonfatal infections or naturally occurring, peracute, fatal infections.

Animals—22 calves that were 6 to 9 months old.

Procedure—The study used BVDV isolates 17011, 713, and 5521 that originated from fetuses aborted from cows with transient, nonfatal, acute BVDV infections and isolates 23025 and 17583 that originated from the tissues of cattle with peracute, fatal BVDV infections. Calves were allotted to 6 groups (1, mockinfected control calves [n = 2]; 2, inoculated with BVDV 17011 [4]; 3, inoculated with BVDV 713 [4]; 4, inoculated with BVDV 5521 [4]; 5, inoculated with BVDV 23025 [4]; and 6, inoculated with BVDV 17583 [4]). Rectal temperatures and clinical signs of disease were recorded daily. Total and differential WBC and platelet counts were performed. Histologic examination and immunohistochemical analysis were conducted to detect lesions and distribution of viral antigens, respectively.

Results—Calves inoculated with BVDV 23025 or 17583 developed more severe clinical signs of disease (fever and diarrhea), more severe lymphopenia, and more severe lesions (alimentary epithelial necrosis, lymphoid depletion, and BVDV antigen deposition in lymphatic tissues), compared with calves inoculated with BVDV 713, 5521, or 17011.

Conclusions and Clinical Relevance—Relative severity of experimentally induced infections corresponded to severity of clinical signs of naturally occurring infections with respective BVDV isolates. (Am J Vet Res2002;63:1379–1384)
Plasma concentrations of adrenocorticotrophic hormone and α-melanocyte-stimulating hormone in ferrets (Mustela putorius furo) with hyperadrenocorticism
Authors: Schoemaker Nico J. , Mol Jan A. , Lumeij J. T. , Rijnberk Ad
Published: December 2005

Objective—To determine plasma concentrations of adrenocorticotrophic hormone (ACTH) and α-melanocyte stimulating-hormone (α-MSH) in healthyferrets and ferrets with hyperadrenocorticism.

Animals—16 healthy, neutered, privately owned ferrets, 28 healthy laboratory ferrets (21 sexually intact and 7 neutered), and 28 ferrets with hyperadrenocorticism.

Procedures—Healthy ferrets were used for determination of reference plasma concentrations of ACTH and α-MSH. Diagnosis of hyperadrenocorticism was made on the basis of history, clinical signs, urinary corticoid-to-creatinine ratios, ultrasonography of the adrenal glands, and macroscopic or microscopic evaluation of the adrenal glands. Blood samples were collected during isoflurane anesthesia. Plasma concentrations of ACTH and α-MSH were measured by radioimmunoassay.

Results—Plasma concentrations of ACTH in 23 healthy neutered ferrets during the breeding season ranged from 4 to 145 ng/L (median, 50 ng/L). Plasma concentrations of α-MSH in 44 healthy neutered or sexually intact ferrets during the breeding season ranged from < 5 to 617 ng/L (median, 37 ng/L). Reference values (the central 95% of the values) for ACTH and α-MSH were 13 to 100 ng/L and 8 to 180 ng/L, respectively. Plasma concentrations of ACTH and α-MSH in ferrets with hyperadrenocorticism ranged from 1 to 265 ng/L (median, 45 ng/L) and 10 to 148 ng/L (median, 46 ng/L), respectively. These values were not significantly different from those of healthy ferrets. Plasma ACTH concentrations of sexually intact female ferrets in estrus were significantly higher than those of neutered females.

Conclusions and Clinical Relevance—Ferrets with hyperadrenocorticism did not have detectable abnormalities in plasma concentrations of ACTH or α-MSH. The findings suggest that hyperadrenocorticism in ferrets is an ACTH and α-MSH-independent condition.—(Am J Vet Res2002;63:1395–1399)
Computed tomography of the elbow joint in clinically normal dogs
Authors: Rycke Lieve M. De , Gielen Ingrid M. , Bree Henri van , Simoens Paul J.
Published: December 2005

Objective—To use computed tomography (CT) to provide a detailed description of elbow joint structures in clinically normal dogs.

Animals—6 clinically normal adult mixed-breed dogs weighing 24 to 37 kg and one 12-month-old Labrador Retriever weighing 27 kg.

Procedure—To perform CT of both elbow regions, dogs were anesthetized and placed in lateral recumbency. One- and 2-mm contiguous slices were obtained by use of a third generation computed tomographic scanner. Good resolution and anatomic detail were acquired from the computed tomographic images by use of a bone (window width, 3,500 Hounsfield units; window level, 500 Hounsfield units) and soft-tissue setting (window width, 400 Hounsfield units; window level, 66 Hounsfield units). After euthanasia, the forelimbs from the Labrador Retriever were removed and frozen in water at –18oC. Elbow joints were sectioned into approximately 1- mm-thick slab sections by use of an electric planer. Anatomic sections were photographed and compared with the corresponding computed tomographic images. Computed tomographic reconstructions of the elbow joint were created in sagittal and dorsal planes.

Results—Structures on the computed tomographic images were matched with structures in the corresponding anatomic sections. The entire humeroradioulnar joint surface could be evaluated on the reconstructed images in the sagittal and dorsal plane.

Conclusions and Clinical Relevance—Computed tomographic images provide full anatomic detail of the bony structures of the elbow joint in dogs. Muscles, large blood vessels, and nerves can also be evaluated. These results could be used as a basis for evaluation of computed tomographic images of the forelimbs of dogs with elbow joint injuries. (Am J Vet Res2002;63:1400–1407)
Effect of growth and training on muscle adaptation in Thoroughbred horses
Authors: Yamano Seiko , Eto Daisuke , Sugiura Takao , Kai Makoto , Hiraga Atsushi , Tokuriki Mikihiko , Miyata Hirofumi
Published: December 2005

Objective—To determine the effect of growth and training on metabolic properties in muscle fibers of the gluteus medius muscle in adolescent Thoroughbred horses.

Animals—Twenty 2-year-old Thoroughbreds.

Procedure—Horses were randomly assigned to 2 groups. Horses in the training group were trained for 16 weeks, and control horses were kept on pasture without training. Samples were obtained by use of a needle-biopsy technique from the middle gluteus muscle of each horse before and after the training period. Composition and oxidative enzyme (succinic dehydrogenase [SDH]) activity of each fiber type were determined by use of quantitative histochemical staining procedures. Whole-muscle activity of SDH and glycolytic enzyme (phosphofructokinase) as well as myosin heavy-chain isoforms were analyzed biochemically and electrophoretically, respectively.

Results—The SDH activity of type-I and -IIA fibers increased during growth, whereas whole-muscle activity was unchanged. Percentage of type-IIX/B muscle fibers decreased during training, whereas that of myosin heavy-chain IIa increased. The SDH activity of each fiber type as well as whole-muscle SDH activity increased during training. An especially noticeable increase in SDH activity was found in type-IIX/B fibers.

Conclusions and Clinical Relevance—Changes in muscle fibers of adolescent Thoroughbreds are caused by training and not by growth. The most noticeable change was for the SDH activity of type-IIX/B fibers. These changes in the gluteus medius muscle of adolescent Thoroughbreds were considered to be appropriate adaptations to running middle distances at high speeds. (Am J Vet Res2002;63:1408–1412)
Changes in concentrations of neuroendocrine hormones and catecholamines in dogs with myocardial failure induced by rapid ventricular pacing
Authors: Roche Brian M. , Schwartz Denise , Lehnhard Robert A. , McKeever Kenneth H. , Nakayama Tomohiro , Kirby Timothy E. , Robitaille Pierre-Marie L. , Hamlin Robert L.
Published: December 2005

Objective—To describe neuroendocrine responses
that develop in dogs subjected to prolonged periods
of ventricular pacing.

Animals—14 adult male hound-type dogs.

Procedure—Samples were obtained and neuroendocrine
responses measured before (baseline) and
after 3 periods of ventricular pacing. A pacemaker
was used to induce heart rates of 180, 200, and 220
beats/min (BPM). Each heart rate was maintained for
3 weeks before increasing to the next rate. Atrial
natriuretic peptide, antidiuretic hormone, aldosterone,
norepinephrine, epinephrine, and dopamine
concentrations and plasma renin activity were measured.
Severity of left ventricular compromise was
estimated.

Results—Shortening fraction decreased significantly
with increasing heart rates (mean ± SE, 35.5 ± 1.4,
25.0 ± 1.4, 19.5 ± 1.9, and 12.2 ± 2.3 for baseline, 180
BPM, 200 BPM, and 220 BPM, respectively). Atrial
natriuretic peptide concentrations increased significantly
at 180 BPM (44.1 ± 3.0 pg/mL) and 200 BPM
(54.8 ± 5.5 pg/mL), compared with baseline concentration
(36.8 ± 2.6 pg/mL). Dopamine concentration
increased significantly at 200 BPM (70.4 ± 10.4
pg/mL), compared with baseline concentration (44.2
± 7.3 pg/mL). Norepinephrine concentrations
increased significantly from baseline concentration
(451 ± 46.2 pg/mL) to 678 ± 69.8, 856 ± 99.6, and
1,003 ± 267.6 pg/mL at 180, 200, and 220 BPM,
respectively.

Conclusions and Clinical Relevance—Dogs subjected
to ventricular pacing for 9 weeks developed neuroendocrine
responses similar to those that develop
in humans with more chronic heart failure and, except
for epinephrine concentrations, similar to those for
dogs subjected to ventricular pacing for < 6 weeks.
(Am J Vet Res 2002;63:1413–1417)
Cutaneous analgesia, hemodynamic and respiratory effects, and β-endorphin concentration in spinal fluid and plasma of horses after acupuncture and electroacupuncture
Authors: Skarda Roman T. , Tejwani Gopi A. , Muir III William W.
Published: December 2005

Objective—To determine cutaneous analgesia, hemodynamic and respiratory effects, and β-endorphin concentration in spinal fluid and plasma of horses after acupuncture and electroacupuncture (EA).

Animals—8 healthy 10- to 20-year-old mares that weighed between 470 and 600 kg.

Procedure—Each horse received 2 hours of acupuncture and 2 hours of PAES at acupoints Bladder 18, 23, 25, and 28 on both sides of the vertebral column as well as sham needle placement (control treatment). Each treatment was administered in a random order. At least 7 days elapsed between treatments. Nociceptive cutaneous pain threshold was measured by use of skin twitch reflex latency (STRL) and avoidance to radiant heat (≤ 50°C) in the lumbar area. Skin temperature, cardiovascular and respiratory variables, and β-endorphin concentration in spinal fluid (CSF-EN) and plasma (plasma-EN) were measured.

Results—Acupuncture and EA significantly increased STRL and skin temperature. The CSF-EN was significantly increased from baseline values 30 to 120 minutes after onset of EA, but it did not change after acupuncture and control treatments. Heart and respiratory rates, rectal temperature, arterial blood pressure, Hct, total solids and bicarbonate concentrations, base excess, plasma-EN, and results of blood gas analyses were not significantly different from baseline values after acupuncture, EA, and control treatments.

Conclusion and Clinical Relevance—Administration of EA was more effective than acupuncture for activating the spinal cord to release β-endorphins into the CSF of horses. Acupuncture and PAES provided cutaneous analgesia in horses without adverse cardiovascular and respiratory effects. (Am J Vet Res2002;63:1435–1442)
Detection of a genetic mutation for myotonia congenita among Miniature Schnauzers and identification of a common carrier ancestor
Authors: Bhalerao Dilip P. , Rajpurohit Yashoda , Vite Charles H. , Giger Urs
Published: December 2005

Objective—To develop a molecular genetic test to detect the mutant skeletal muscle chloride channel (ClC-1) allele that causes myotonia congenita in Miniature Schnauzers and to analyze the relationship of affected and carrier dogs.

Animals—372 Miniature Schnauzers from the United States, Canada, Australia, and Europe that were tested between March 2000 and October 2001.

Procedure—The sequence surrounding the mutation in the ClC-1 allele was amplified by use of a unique pair of primers. Polymerase chain reaction (PCR) products were digested with the restriction enzymeHpyCH4 III and separated on a 6% polyacrylamide gel. Pedigrees from all available carrier and affected dogs were analyzed, and a composite pedigree was established.

Results—Enzyme digestion of PCR products of the normal ClC-1 allele resulted in 3 fragments of 175, 135, and 30 bp, whereas PCR products of the mutant allele resulted in fragments of only 175 and 165 bp. Of the 372 Miniature Schnauzers, 292 (78.5%) were normal, 76 (20.4%) were carriers, and 4 (1.1%) were affected (myotonic) dogs. Frequency of the mutant allele was 0.113. Pedigree analysis revealed that a popular sire, documented to be a carrier, was a common ancestor of all carriers and affected dogs.

Conclusions and Clinical Relevance—A PCR-based enzyme digestion DNA test was developed. The mutant allele for this disease is frequent in Miniature Schnauzers that are related to a common carrier ancestor. Breeding dogs should be tested by this specific DNA test to help limit the spread of this deleterious mutation. (Am J Vet Res2002;63:1443–1447)