bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of enrofloxacin and ciprofloxacin hydrochloride on canine and equine chondrocytes in culture
Authors: Egerbacher Monika , Edinger Johannes , Tschulenk Waltraud 
Published: December 2005

AbstractObjective—To study chondrotoxic effects of enrofloxacin (ENR) and ciprofloxacin hydrochloride (CFX) on canine and equine articular chondrocytes in culture and to compare the effects with that of cultivation in Mg2+-free medium.Sample Population—Chondrocytes from articular cartilage of 4- and 6 -month old dogs and 2- to 4- year-old horses.Procedure—Chondrocytes were cultivated with 10, 40, 80, and 160 μg of CFX/ml, 10, 50, 100, and 150 μg of ENR/ml, or in Mg2+-free medium. A live-to-dead test was performed to test cytotoxic effects. Morphologic changes were evaluated by electron microscopy. An attachment assay was used to test the ability of chondrocytes to adhere to collagen type- II coated-chamber slides in the presence of CFX and with Mg2+-free medium.Results—Chondrocytes cultivated in quinolone-supplemented medium or Mg2+-free medium had a decreased ability to adhere to culture dishes. Cell shape and the actin and vimentin cytoskeleton changed in a concentration-dependent manner. These effects were not species-specific and developed with both quinolones. On day 1 of culture, adhesion of chondrocytes to collagen type II was reduced to 70 and 45% of control values in the CFX treatment and Mg2+-free treatment groups, respectively. On day 5 of culture, adhesion of chondrocytes was reduced to 45 and 40% of control values in the CFX treatment and Mg2+-free treatment groups, respectively.Conclusion and Clinical Relevance—In vitro, chondrotoxic effects of quinolones appear to be the result of irregular integrin signaling and subsequent cellular changes. Drug concentrations leading to morphologic changes in vitro may be achieved in articular cartilage in vivo. (Am J Vet Res2001;62:704–708)
Arthrocentesis of the temporomandibular joint in adult horses
Authors: Rosenstein Diana S. , Bullock Matthew F. , Ocello Peter J. , Clayton Hilary M. 
Published: December 2005

AbstractObjective—To develop a method for arthrocentesis of the temporomandibular joint in adult horses.Animals—7 equine cadaver heads and 6 clinically normal adult horses.Procedure—Fluoroscopy, contrast radiography, and computed tomography were used on cadaver specimens to locate the temporomandibular joint, identify externally palpable landmarks for joint access, guide needle placement into the joint, and illustrate regional anatomy. The arthrocentesis technique was performed on 6 live healthy adult horses to determine efficacy and safety of this procedure.Results—Externally palpable structures were identified as landmarks for temporomandibular arthrocentesis, including the lateral border of the condylar process of the mandible, the zygomatic process of the temporal bone, and the lateral pericapsular fat pad. Arthrocentesis was successful in all 6 joints in the live horses, and no complications developed.Conclusions and Clinical Relevance—The technique identified will improve the ability to examine and treat the temporomandibular joint in horses. (Am J Vet Res2001;62:729–735).
Bovine papillomavirus DNA in neoplastic and nonneoplastic tissues obtained from horses with and without sarcoids in the western United States
Authors: Carr Elizabeth A. , Théon Alain P. , Madewell Bruce R. , Griffey Stephen M. , Hitchcock Margaret E. 
Published: December 2005

Abstract

Objective—To determine the incidence of bovine
papillomavirus (BPV) type 1 or 2 in sarcoids and other
samples of cutaneous tissues collected from horses
in the western United States.

Animals—55 horses with sarcoids and 12 horses
without sarcoids.

Procedure—Tissue samples (tumor and normal skin
from horses with sarcoids and normal skin, papillomas,
and nonsarcoid cutaneous neoplasms from
horses without sarcoids) were collected. Tissue samples
were analyzed for BPV-1 or -2 DNA, using a polymerase
chain reaction (PCR) and restriction fragment
length polymorphism. The PCR products from 7 sarcoid-
affected horses were sequenced to evaluate percentage
homology with expected sequences for BPV-1 or -2.

Results—Most (94/96, 98%) sarcoids contained BPV
DNA. Sixty-two percent of the tumors examined had
restriction enzyme patterns consistent with BPV-2.
Thirty-one of 49 (63%) samples of normal skin
obtained from horses with sarcoids contained BPV
DNA. All samples subsequently sequenced had
100% homology with the expected sequences for the
specific viral type. All tissues from healthy horses,
nonsarcoid neoplasms, and papillomas were negative
for BPV DNA.

Conclusions and Clinical Relevance—Bovine papillomaviral
DNA was detected in essentially all sarcoids
examined. There appears to be regional variation in
the prevalence of viral types in these tumors. The fact
that we detected viral DNA in normal skin samples
from horses with sarcoids suggests the possibility of
a latent viral phase. Viral latency may be 1 explanation
for the high rate of recurrence following surgical excision
of sarcoids. (Am J Vet Res 2001;62:741–744)
Comparison of heartworm extract-induced shock and endotoxin-induced shock in dogs by determination of serum tumor necrosis factor concentrations
Authors: Kitoh Katsuya , Katoh Hiroko , Kitagawa Hitoshi , Sasaki Yoshihide 
Published: December 2005

AbstractObjective—To compare the mechanisms of heartworm (HW) extract-induced shock and endotoxininduced shock in dogs by determination of serum tumor necrosis factor (TNF) concentrations.Animals—11 mixed-breed dogs (7 without and 4 with HW infections).Procedure—Eight dogs were treated with 2 ml of HW extract IV, and 3 dogs were given endotoxin (Escherichia colilipopolysaccharide [LPS]) at 40 or 400 μg/kg of body weight, IV. Changes in clinical and hematologic findings and serum TNF concentrations were examined from before treatment to 120 minutes after treatment in dogs given HW extract or from before treatment to 180 minutes after treatment in dogs given LPS. Tumor necrosis factor concentration was determined by cytotoxic assay, using WEHI-164 murine sarcoma cells, and plasma endotoxin concentration was determined in 2 dogs treated with HW extract, using the endotoxin-specific chromogenic test.Results—Eight dogs developed shock 3 to 16 minutes after HW extract treatment. Rectal temperature did not change during examination. Serum TNF concentration was detected at a low concentration only 60 and 120 minutes after HW extract treatment, and plasma endotoxin was not detected during examination. In dogs treated with LPS, rectal temperature increased to > 40 C in 2 of 3 dogs, and serum TNF concentration began to increase 30 minutes after LPS treatment, reaching a maximum concentration by 60 minutes.Conclusions—The cause and mechanism of HW extract-induced shock may be different from those of endotoxin-induced shock, because TNF, which was a pivotal mediator in endotoxin-induced shock, increased minimally in serum of dogs treated with HW extract. (Am J Vet Res2001;62:765–769)
Pharmacodynamics and pharmacokinetics of ketoprofen enantiomers in sheep
Authors: Arifah Abdul K. , Landoni Maria F. , Frean Stephen P. , Lees Peter 
Published: December 2005

Abstract

Objective—To establish pharmacokinetic and pharmacodynamic
properties of a racemic mixture and
individual R(–) and S(+) enantiomeric forms of ketoprofen
(KTP) in sheep and determine pharmacodynamic
variables of KTP by pharmacokinetic-pharmacodynamic
modeling.

Animals—8 female Dorset crossbred sheep.

Procedure—A tissue cage model of inflammation
was used. Carrageenan was administered into tissue
cages. Time course of cyclooxygenase (COX)-2 inhibition
was determined in vivo by measurement of exudate
prostaglandin E2 (PGE2) concentrations. Time
course of COX-1 inhibition was determined ex vivo by
measurement of serum thromboxane B2 (TXB2) concentrations.
In addition, plasma concentration-time
course and penetration of KTP enantiomers into
inflammatory exudate and transudate (noninflamed
tissue cage fluid) were investigated. Four treatments
were compared: placebo, racemic mixture (rac-KTP [3
mg/kg of body weight, IV]), S(+) KTP (1.5 mg/kg,
IV),and R(–) KTP (1.5 mg/kg, IV).

Results—Both KTP enantiomers had elimination halflife
and mean residence time measurements that
were short and volume of the central compartment
and steady state volume of distribution that were low.
Clearance was rapid, particularly for R(–) KTP.
Elimination of both enantiomers from exudate was >
10 times slower than from plasma. Both rac-KTP and
the individual enantiomers significantly inhibited
serum TXB2 concentrations for 12 hours. Rac-KTP and
S(+) KTP, but not R(–) KTP, also significantly inhibited
PGE2 synthesis in exudate for 12 hours.

Conclusions and Clinical Relevance—Inhibition of
serum TXB2 concentration and exudate PGE2 synthesis
for similar time courses after S(+) KTP administration
indicates that it is a nonselective inhibitor of COX
in sheep. ( Am J Vet Res 2001;62:77–86)
Role of histamine in heartworm extract-induced shock in dogs
Authors: Kitoh Katsuya , Katoh Hiroko , Kitagawa Hitoshi , Nagase Masayuki , Sasaki Nobuo , Sasaki Yoshihide 
Published: December 2005

AbstractObjective—To determine whether heartworm (HW) extract-induced shock in dogs is consistent with anaphylactic shock by examining the role of histamine.Animals—6 mixed-breed dogs (3 without and 3 with HW infections) and 4 specific pathogen-free (SPF) Beagles.Procedure—Four experiments were performed as follows: 1) 6 mixed-breed dogs were treated IV with 2 ml of HW extract, and plasma histamine concentrations were determined; 2) 4 SPF dogs were treated IV with 2 ml of HW extract and examined for shock; 3) sera from 6 dogs of experiment 1 and from 4 SPF dogs of experiment 2 that were obtained before HW extract treatment were tested for heterologous passive cutaneous anaphylaxis (PCA), using rabbits during a sensitization period of 48 to 72 hours; and 4) mast cell degranulation by HW extract was tested, using rat mesentery and canine cultured mast cells.Results—Experiment 1: 6 dogs developed shock, and plasma histamine concentrations increased significantly from 0.3 ± 0.2 (mean ± SD) ng/ml before HW extract treatment to 44.6 ± 68.9 ng/ml at the onset of shock; experiment 2: all SPF dogs developed shock and had an increase in plasma histamine concentrations; experiment 3: sera from mixed-breed dogs without HW infection and from SPF dogs had negative PCA reactions; experiment 4: HW extract degranulated rat mesentery mast cells and released histamine directly from canine mast cells.Conclusions and Clinical Relevance—Results of our study indicate that an unknown mast cell-degranulating substances contained in HW extract may degranulate mast cells directly, consequently releasing histamine that may participate in the onset of shock in HW extract-induced shock in dogs. (Am J Vet Res2001;62:770–774)
Blood oxygen binding in calves with naturally occurring diarrhea
Authors: Cambier Carole , Clerbaux Thierry , Moreaux Benoít , Detry Bruno , Beerens Dominique , Frans Albert , Gustin Pascal 
Published: December 2005

AbstractObjective—To assess blood oxygen binding in calves with diarrhea.Animals—22 dairy and 26 double-muscled calves with diarrhea, 31 healthy dairy calves and 37 healthy double-muscled calves.Procedure—Severity of disease, including the ability of affected calves to stand, was evaluated. Hydration and signs of depression were scored. Venous and arterial blood samples were collected, and 2,3-diphosphoglycerate, ATP, chloride, inorganic phosphate, lactate, pyruvate, total protein, albumin, and hemoglobin concentrations, and Hct, pH, Pco2, and Po2were determined. Oxygen equilibrium curves (OEC) were constructed under standard conditions, and oxygen extraction ratios were calculated.Results—Recumbent calves of both breed-types were more dehydrated and had more severe signs of depression than ambulatory affected calves. In both breed-types, hemoglobin oxygen affinity was increased in calves with diarrhea, compared with healthy calves, as indicated by a decrease in standard partial oxygen pressure (P50). Diarrhea induced hypocapnia and hypothermia in the most severely affected calves, which counteracted the acidosisinduced right shift in arterial and venous OEC. Arterial and venous P50 were significantly less in doublemuscled calves with diarrhea than healthy calves, whereas P50 for affected dairy calves were similar to those of healthy calves. Except in the most severely affected dairy calves, oxygen extraction ratio was significantly less in calves with diarrhea, compared with healthy calves.Conclusions and Clinical Relevance—Release of oxygen from blood may be impaired in calves with diarrhea, depending on the effect of the disease on certain blood biochemical variables. (Am J Vet Res2001;62:799–804).
Myofibroblasts in the accessory ligament (distal check ligament) and the deep digital flexor tendon of foals
Authors: Hartzel Dina K. , Arnoczky Steven P. , Kilfoyle S. Jean , Stick John A. 
Published: December 2005

AbstractObjective—To demonstrate myofibroblasts in the accessory ligament of the deep digital flexor tendon (ie, distal check ligament) and deep digital flexor tendon of clinically normal foals.Sample Population—Tissue specimens from 25 foals that were necropsied for reasons unrelated to this study and unrelated to musculoskeletal disease.Procedure—The distal check ligament and deep digital flexor tendon of both forelimbs were examined histologically. Myofibroblasts were identified by immunohistochemical staining specific for alphasmooth muscle actin (α-SMA).Results—Most of the cells in the distal check ligament and deep digital flexor tendon of all foals stained positive for α-SMA.Conclusion and Clinical Relevance—Myofibroblasts made up most of the cells in the distal check ligament and deep digital flexor tendon of clinically normal foals. These cells have contractile ability and therefore, may play a role in flexure contracture of these tendons. The ability of tetracycline to chelate calcium or decrease the expression of the contractile protein α-smooth muscle actin could inhibit the myofibroblasts' ability to contract, thus providing a rationale for tetracycline administration as a treatment of distal interphalangeal joint flexor deformity in foals. (Am J Vet Res2001;62:823–827)
Metabolic and structural abnormalities in dogs with early left ventricular dysfunction induced by incessant tachycardia
Authors: Mc Entee Kathleen , Flandre Thierry , Dessy Cécile , Desmecht Daniel , Clercx Cécile , Balligand Marc , Michaux Charles , Jonville Eva , Miserque Nathalie , Henroteaux Marc , Keene Bruce 
Published: December 2005

AbstractObjective—To assess morphologic and metabolic abnormalities in dogs with early left ventricular dysfunction (ELVD) induced by rapid right ventricular pacing (RRVP).Animals—7 Beagles.Procedure—Plasma carnitine concentrations were measured before and after development of ELVD induced by RRVP. At the same times, transvenous endomyocardial biopsy was performed, and specimens were submitted for determination of myocardial carnitine concentrations and histologic, morphometric, and ultrastructural examination.Results—In 4 dogs in which baseline plasma total carnitine concentration was normal, RRVP induced a decrease in myocardial total and free carnitine concentrations and an increase in myocardial esterified carnitine concentration. In 3 dogs in which baseline plasma total carnitine concentration was low, plasma and myocardial carnitine concentrations were unchanged after pacing. Structural changes associated with pacing included perinuclear vacuolization in 3 dogs. Morphometric analyses indicated there was a decrease in myofiber cross-sectional diameter and area following pacing. Electron microscopy revealed changes in myofibrils and mitochondria following pacing.Conclusions and Clinical Relevance—Results indicated that moderate to severe alterations in myocyte cytoarchitecture are present in dogs with ELVD induced by RRVP and that in dogs with normal plasma carnitine concentrations, myocardial carnitine deficiency may be a biochemical marker of ELVD. Results also indicated that transvenous endomyocardial biopsy can be used to evaluate biochemical and structural myocardial changes in dogs with cardiac disease. (Am J Vet Res2001;62:889–894)
Characterization of Pasteurellaspp isolated from healthy domestic pack goats and evaluation of the effects of a commercial Pasteurella vaccine
Authors: Ward Alton C. S. , Weiser Glen C. , DeLong Walter J. , Frank Glynn H. 
Published: December 2005

AbstractObjective—To characterizePasteurellaspp isolated from healthy pack goats and evaluate the effects of administration of a commercialPasteurellavaccine.Animals—45 goats.Procedure—Pharyngeal swab specimens and blood samples were collected on day 0 before vaccination with aPasteurella(Mannheimia) haemolyticaserotype A1 bacterin. Samples were also collected from 17 goats on days 21 and 35. IsolatedPasteurellaspp were assigned to biovariant groups on the basis of results of biochemical utilization tests and serotyped. Serum antibody titers were determined.Results—Multiple strains ofPasteurellaspp were isolated from swab specimens and assigned to 30 nonhemolytic and 14 β-hemolytic biovariant groups. The most common biovariant isolated was nonhemolyticP trehalosibelonging to group 2. This strain was isolated from 41 goats. NonhemolyticP haemolyticastrains were isolated from 31 goats, whereas β-hemolytic strains ofP trehalosiandP haemolyticawere isolated from 8 and 35 goats, respectively. Vaccination with the A1 serotype did not affect the proportion of goats from which we isolated each biovariant group or the number of biovariant groups isolated.Conclusion and Clinical Relevance—Multiple strains ofP haemolyticaandP trehalosibelonging to nonhemolytic and β-hemolytic biovariant groups were isolated from the pharynx of healthy domestic pack goats. Because hemolytic activity correlates with leukotoxin production, β-hemolytic strains may have a greater potential to cause disease in naive populations of wild ruminants. However, vaccination with an A1 serotype bacterin did not decrease the proportion of culture-positive goats. (Am J Vet Res2002;63:119–123)
Effects of management, feeding, and treatment on clinical and biochemical variables in cattle with displaced abomasum
Authors: Stengärde Lena U. , Pehrson Bo G. 
Published: December 2005

AbstractObjective—To determine effects of management, feeding, and treatment on clinical and biochemical variables in cows with displaced abomasum (DA).Animals—374 cows that received 470 treatments for DA.Procedure—Blood and milk samples were obtained from 139 affected cows for analysis; for all cows, clinical data, management, feeding, and treatments were evaluated.Results—Multiparous cows were more predisposed to DA than primiparous cows were, and Swedish Friesians were more predisposed than Swedish Red and Whites were. Eighty percent of cows had leftsided DA, and 20% had right-sided DA. In > 50% of affected cows, clinical signs appeared just before calving to 2 weeks after calving. Incidence of twin calves and periparturient diseases was significantly higher in affected cows than in the overall Swedish cow population. Content of neutral detergent fiber in the silage was low in herds with DA. Feeding a total mixed ration was a risk factor for DA. Treatment by surgical methods gave a significantly higher recovery rate than nonsurgical methods.Conclusion and Clinical Relevance—Displaced abomasum is a periparturient nutritional disease. Feeding roughage with low neutral detergent content is a more important causative factor than the amount of concentrates fed at the time of calving. The basic principle for prevention of DA is to maintain good ruminal filling before and at calving. The amount of high-quality roughage fed before and at calving should be kept to a minimum. By changing routines for periparturient feeding, it should be possible to reduce the incidence of DA. (Am J Vet Res2002;63:137–142)
Evaluation of splanchnic oxygen extraction ratio as an index of portal vein pressure in dogs
Authors: MacPhail Catriona M. , Monnet Eric , Gaynor James S. 
Published: December 2005

AbstractObjective—To determine changes in splanchnic oxygen extraction ratio during experimentally induced portal hypertension in dogs.Animals—6 clinically normal dogs.Procedure—Standard midline laparotomy and median sternotomy were performed in anesthetized dogs. Baseline measurements of arterial blood pressure, aortic blood flow, portal vein blood flow, and portal vein pressure were acquired, and arterial, venous, and portal vein blood samples were obtained to determine systemic and splanchnic oxygen extraction ratios. The portal vein was gradually occluded until a pressure of 18 cm of H2O was reached; this pressure was maintained for 30 minutes, and measurements and collection of blood samples were repeated.Results—Portal vein blood flow decreased significantly from 457 ± 136 ml/min before to 266 ± 83 ml/min after induction of portal hypertension. Oxygen content in the portal vein significantly decreased from 12.3 ± 1.85 to 8.2 ± 2.31%, and splanchnic oxygen extraction ratio significantly increased from 15.8 ± 6.2 to 37.4 ± 10.9% during portal hypertension. There was a significant inverse correlation between portal vein blood flow and splanchnic oxygen extraction ratio at baseline and during portal hypertension.Conclusion and Clinical Relevance—An increase in splanchnic oxygen extraction ratio is evident with partial attenuation of the portal vein and the concurrent decrease in portal vein blood flow. Correlation of oxygen extraction ratio with portal vein blood flow may be a more important indicator for determination of an endpoint to prevent congestion and ischemia of the gastrointestinal tract and pancreas during ligation of portosystemic shunts. (Am J Vet Res2002;63:15–18)
Effects of aerosolized feedyard dust that contains natural endotoxins on adult sheep
Authors: Purdy Charles W. , Straus David C. , Chirase Norbert , Parker David B. , Ayers J. R. , Hoover Mark D. 
Published: December 2005

AbstractObjective—To determine the clinical, clinicopathologic, and histologic effects of aerosolized feedyard dust that contains natural endotoxins on adult sheep.Animals—Eighteen 3-year-old Saint Croix sheep.Procedure—A prospective randomized controlled study was conducted. There were 2 treatment groups (dust-endotoxin group, n = 9; control group, 9). Aerosolized feedyard dust was provided continuously during a 4-hour period for each application (once in week 1, 3 times in week 2, and 7 times in week 3) to sheep in a semiairtight tent. All sheep were euthanatized and necropsied 8 hours after the treatment group received the last dust treatment. Variables measured before and after each dust treatment were rectal temperature, total WBC count, and concentrations of fibrinogen and haptoglobin.Results—Mean amount of dust administered during each treatment was 451 g/4 h. Filter collection indicated 51 mg of dust/m3and 7,423 ng of endotoxin. Mean rectal temperature at 8 hours (40.4 C) and mean WBC counts 12 and 24 hours after dust treatment were significantly higher for the treated group than the means of the respective variables for the control group. Similar responses were observed with repeated dust-endotoxin treatments; however, with each subsequent treatment, there was a diminished response. Sheep in the treatment group had generalized alveolar septal thickening and hypercellularity.Conclusion and Clinical Relevance—Feedyard dust induced a temporary febrile response and leukocytosis in sheep in the treatment group. Exposure to dust that contains endotoxins may be a stressor preceding acute infectious respiratory tract disease of marketed sheep. (Am J Vet Res2002;63:28–35)