bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of a single injection of a sustained-release formulation of moxidectin for prevention of experimental heartworm infection after 12 months in dogs
Authors: Holm-Martin Merete , Atwell Rick 
Published: December 2005

Abstract

Objective—To evaluate the efficacy of a single injection
of a sustained-release formulation of moxidectin
in preventing heartworm (Dirofilaria immitis) infection
for 12 months in dogs.

Animals—14 healthy dogs.

Procedure—Group A (nontreated control dogs; n = 6)
received sterile vehicle administered SC, and group B
(treated dogs; n = 6) received a sustained-release formulation
of moxidectin administered SC. All dogs
were housed in a heartworm-endemic area for 11.5
months, and heartworm antigen and modified Knott
tests were performed monthly. All dogs (including 2
additional control dogs [group C]) were then inoculated
with infective-stage larvae (L3) of D immitis, and
4.5 months later, all dogs were euthanatized and postmortem
examinations were performed. Adult D immitis
were counted and measured, and their age was
estimated.

Results—All dogs in groups A and C were infected
with young (4- to 4.5-month old) adult male and
female D immitis. No dogs in group B were infected
with heartworms.

Conclusions and Clinical Relevance—The age of
heartworms recovered suggests that infection was
the result of experimental inoculation and not natural
exposure to mosquitoes during the 11.5-month period
the dogs resided in a heartworm-endemic area. A single
SC injection of a sustained-release formulation of
moxidectin was effective in providing protection
against heartworm infection after 12 months in dogs.
This formulation is a convenient method of heartworm
prophylaxis that could eliminate the problem of
poor owner compliance. (Am J Vet Res 2004;
65:1596–1599)
High-frequency ultrasonography of the skin of clinically normal dogs
Authors: Diana Alessia , Preziosi Rosario , Guglielmini Carlo , Degliesposti Paolo , Pietra Marco , Cipone Mario 
Published: December 2005

Abstract

Objective—To assess the applicability of high-frequency
diagnostic ultrasonography for evaluation and
accurate measurement of the skin thickness of clinically
normal dogs.

Animals—26 healthy dogs (12 sexually intact males,
13 sexually intact females, and 1 spayed female) of
various breeds and ages.

Procedure—Ultrasonographic examination of the
skin and histomorphometric analysis of skin biopsy
specimens obtained from the same site were performed.
A 13-MHz linear-array transducer was used to
obtain a series of ultrasonographic images of the skin
in the flank region; images were analyzed and measured
by use of imaging software. Cutaneous biopsy
specimens were placed in fixative and then stained
with H&E and Masson trichrome stains.
Histomorphometric analysis was performed by use of
an image analyzer. Thickness of the epidermis and
dermis of each specimen was evaluated by use of a
semiautomatic procedure of quantification. Data
obtained from ultrasonographic and histologic measurements
were compared by use of the Pearson correlation
test.

Results—The ultrasonographic pattern of canine skin
was consistently characterized by 3 distinct, defined
echogenic layers corresponding to the epidermal
entry echo, epidermis and dermis, and subcutaneous
tissues. A positive correlation was found between
ultrasonographic and histologic measurements of
skin thickness.

Conclusions and Clinical Relevance—Comparison
between ultrasonographic and histologic appearance
of the skin revealed that layering of canine skin (ie,
epidermis and dermis) and the subcutaneous tissues
may be recognized and measured by use of high-frequency
ultrasonography. Thus, diagnostic ultrasonography
may be a useful tool for the noninvasive evaluation
of cutaneous disorders in dogs. (Am J Vet Res
2004;65:1625–1630)
Assessment of changes in hemostatic markers in Cavalier King Charles Spaniels with myxomatous mitral valve disease
Authors: Tarnow Inge , Kristensen Annemarie T. , Olsen Lisbeth H. , Pedersen Henrik D. 
Published: December 2005

AbstractObjective—To evaluate markers of hemostasis and their relationship to the degree of mitral regurgitation (MR) and platelet function in Cavalier King Charles Spaniels (CKCSs) with myxomatous mitral valve disease.Animals—76 clinically healthy CKCSs and 24 control dogs.Procedure—All dogs underwent echocardiographic examination; various hemostatic, hematologic, and biochemical variables were evaluated in blood. The CKCSs were allocated to 1 of 3 groups on the basis of MR severity. In 8 control dogs and 8 CKCSs, plasma von Willebrand factor (vWF) multimer analysis was performed.Results—Compared with control dogs, plasma fibrinogen concentration was higher in all CKCSs and related to left ventricular end diastolic diameter and left atrial-to-aortic root ratio among all CKCSs. The activated partial thromboplastin times and plasma Ddimer concentration were similar among the 4 groups. Plasma vWF concentration was lower in CKCSs with moderate to severe MR, compared with that of CKCSs with no MR and control dogs. There was a relationship between plasma vWF concentration and platelet function in CKCSs but not in control dogs. In 4 CKCSs with moderate to severe MR and low plasma vWF concentration, amounts of vWF high-molecular-weight multimers (HMWMs) were low.Conclusions and Clinical Relevance—In CKCSs, MR appeared to be associated with a low plasma vWF concentration and likely a loss of vWF HMWMs (possibly through their destruction via shear stress to the blood). The importance of the changes in plasma fibrinogen concentration and the thromboembolic risk in dogs with MR remain to be investigated. (Am J Vet Res2004;65:1644–1652)
Pharmacokinetics of a combination preparation of ampicillin and sulbactam in turkeys
Authors: Fernández-Varón Emilio , Cárceles Carlos M. , Espuny Alberto , Marín Pedro , Escudero Elisa 
Published: December 2005

Abstract

Objective—To investigate the disposition kinetics of
ampicillin and sulbactam after IV and IM administration
of an ampicillin-sulbactam (2:1) preparation and
determine the bioavailability of the combined preparation
after IM administration in turkeys.

Animals—10 healthy large white turkeys.

Procedure—In a crossover study, turkeys were
administered the combined preparation IV (20 mg/kg)
and IM (30 mg/kg). Blood samples were collected
before and at intervals after drug administrations.
Plasma ampicillin and sulbactam concentrations were
measured by use of high-performance liquid chromatography;
plasma concentration-time curves were
analyzed via compartmental pharmacokinetics and
noncompartmental methods.

Results—The drugs were distributed according to an
open 2-compartment model after IV administration
and a 1-compartment model (first-order absorption)
after IM administration. For ampicillin and sulbactam,
the apparent volumes of distribution were 0.75 ± 0.11
L/kg and 0.74 ± 0.10 L/kg, respectively, and the total
body clearances were 0.67 ± 0.07 L·kg–1·h–1 and 0.56
± 0.06 L·kg–1·h–1, respectively. The elimination half-lives
of ampicillin after IV and IM administration were 0.78
± 0.12 hours and 0.89 ± 0.17 hours, respectively,
whereas the corresponding half-lives of sulbactam
were 0.91 ± 0.12 hours and 0.99 ± 0.16 hours,
respectively. Bioavailability after IM injection was
58.87 ± 7.65% for ampicillin and 53.75 ± 5.35% for
sulbactam.

Conclusions and Clinical Relevance—Results indicated
that a regimen of loading and maintenance
doses of 300 mg of the ampicillin-sulbactam (2:1)
combination/kg every 8 hours could be clinically useful
in turkeys. This dosage regimen maintained plasma
concentrations of ampicillin > 0.45 µg/mL in
turkeys. (Am J Vet Res 2004;65:1658–1663)
Assessment of the effects of exogenous long-acting insulin on glucose tolerance in alpacas
Authors: Ueda Jaime , Cebra Christopher K. , Tornquist Susan J. 
Published: December 2005

AbstractObjective—To evaluate the effects of long-acting insulin on glucose clearance in alpacas.Animals—8 adult castrated alpacas.Procedure—On 2 days, food was withheld from alpacas for 8 hours. Alpacas were randomly allocated to receive an SC injection of long-acting insulin (0.4 U/kg) or saline (0.9% NaCl) solution 1 hour before the first of 3 administrations of glucose (at 60, 480, and 1,200 minutes after treatment) on day 1 and the alternate treatment and procedure on day 2. Plasma glucose concentration was determined before and 15, 45, 120, and 240 minutes after each glucose administration, and fractional turnover rates were calculated. The data were compared between alpacas with and without insulin administration and among the 3 glucose administrations for each day.Results—Compared with sham-treated alpacas, insulin-treated alpacas had significantly lower blood glucose concentrations from 180 to 600 minutes after treatment; they also had glucose concentrations significantly below baseline values from 120 to 480 minutes, at which time the mean glucose concentration was in the hypoglycemic range. Also, mean fractional turnover of glucose was significantly higher in insulintreated alpacas from 105 through 300 minutes.Conclusions and Clinical Relevance—Compared with known effects of regular insulin in alpacas, the action of long-acting insulin was of slower onset but longer lasting; its administration may induce hypoglycemia, even in alpacas that receive glucose. To maintain the hypoglycemic effect, long-acting insulin may have to be administered more than once daily and blood glucose concentration should be monitored to avoid hypoglycemic complications in alpacas. (Am J Vet Res2004;65:1688–1691)
Investigation of in vitro transdermal absorption of fentanyl from patches placed on skin samples obtained from various anatomic regions of dogs
Authors: Mills Paul C. , Magnusson Beatrice M. , Cross Sheree E. 
Published: December 2005

AbstractObjective—To investigate in vitro transdermal absorption of fentanyl from patches through skin samples obtained from various anatomic regions of dogs.Sample Population—Skin samples from 5 Greyhounds.Procedure—Skin samples from the dogs' thoracic, neck, and groin regions were collected postmortem and frozen. After samples were thawed, circular sections were cut and placed in Franz-type diffusion cells in a water bath (32°C). A commercial fentanyl patch, attached to an acetate strip with a circular hole, was applied to each skin sample. Cellulose strips were used as control membranes. Samples of receptor fluid in the diffusion cells were collected at intervals for 48 hours, and fentanyl concentrations were analyzed by use of high-performance liquid chromatography.Results—Mean ± SD release rate of fentanyl from the patch, defined by its absorption rate through the non–rate-limiting cellulose membrane, was linear during the first 8 hours (2.01 ± 0.05 µg/cm2of cellulose membrane/h) and then decreased. Fentanyl passed through skin from the groin region at a faster rate and with a significantly shorter lag time, compared with findings in neck or thoracic skin samples.Conclusions and Clinical Relevance—In vitro, fentanyl from a patch was absorbed more quickly and to a greater extent through skin collected from the groin region of dogs, compared with skin samples from the thoracic and neck regions. Placement of fentanyl patches in the groin region of dogs may decrease the lag time to achieve analgesia perioperatively; however, in vivo studies are necessary to confirm these findings.(Am J Vet Res2004;65:1697–1700)
Determination of functional and morphologic changes in palmar digital nerves after nonfocused extracorporeal shock wave treatment in horses
Authors: Bolt David M. , Burba Daniel J. , Hubert Jeremy D. , Strain George M. , Hosgood Giselle L. , Henk William G. , Cho Doo-Youn 
Published: December 2005

Abstract

Objective—To determine functional and morphologic
changes in palmar digital nerves after nonfocused
extracorporeal shock wave (ESW) treatment in horses.

Animals—6 horses.

Procedures—The medial and lateral palmar digital
nerves of the left forelimb were treated with nonfocused
ESWs. The medial palmar digital nerve of the
right forelimb served as a nontreated control nerve.
At 3, 7, and 35 days after treatment, respectively, 2
horses each were anesthetized and nerves were surgically
exposed. Sensory nerve conduction velocities
(SNCVs) of treated and control nerves were recorded,
after which palmar digital neurectomies were performed.
Morphologic changes in nerves were
assessed via transmission electron microscopy.

Results—Significantly lower SNCV in treated medial
and lateral nerves, compared with control nerves, was
found 3 and 7 days after treatment. A significantly lower
SNCV was detected in treated medial but not lateral
nerves 35 days after treatment. Transmission electron
microscopy of treated nerves revealed disruption of the
myelin sheath with no evidence of damage to Schwann
cell bodies or axons, 3, 7, and 35 days after treatment.

Conclusions and Clinical Relevance—Nonfocused
ESW treatment of the metacarpophalangeal area resulted
in lower SNCV in palmar digital nerves. This effect
likely contributes to the post-treatment analgesia
observed in horses and may result in altered peripheral
pain perception. Horses with preexisting lesions may be
at greater risk of sustaining catastrophic injuries when
exercised after treatment. (Am J Vet Res
2004;65:1714–1718)
Comparative assessment of bone mineral measurements obtained by use of dual-energy x-ray absorptiometry, peripheral quantitative computed tomography, and chemical-physical analyses in femurs of juvenile and adult dogs
Authors: Schneider Sigrid , Breit Sabine M. , Grampp Stephan , Künzel Wolfgang W. F. , Liesegang Annette , Mayrhofer Elisabeth , Zentek Jürgen 
Published: December 2005

AbstractObjective—To compare bone mineral measurements obtained by use of dual-energy x-ray absorptiometry (DEXA), peripheral quantitative computed tomography (pQCT), and chemical-physical analyses and determine effects of age and femur size on values obtained for the various techniques.Sample Population—Femurs obtained from 15 juvenile and 15 adult large-breed dogs.Procedure—In each femur, 7 regions of interest were examined by use of DEXA to measure the bone mineral content (BMC) and bone mineral density (BMD), and 5 were examined by use of pQCT to measure BMD. Among these, 1 region was examined by both noninvasive methods and an invasive method. Volume of the femur was determined by water displacement. Volumetric bone density (VBD) was calculated. Calcium (Ca), phosphorus (P), total Ca, and total P contents were determined.Results—DEXA- and pQCT-derived results revealed that all values increased with age in juvenile dogs. In adults, VBD and pQCT-derived BMD decreased significantly and DEXA-derived BMD increased with increasing femur length. The pQCT-derived BMD correlated well with VBD and Ca content, whereas DEXA-derived BMC was strongly correlated with Ca content. In juveniles, values correlated regardless of the technique used, whereas in adult dogs, DEXA-derived BMD did not correlate with pQCT-derived BMD, Ca concentration, or VBD unless data were adjusted on the basis of femur length.Conclusions and Clinical Relevance—DEXA-derived BMD adjusted for femur length yields approximately the same percentage variability in VBD as for pQCT-derived BMD. However, pQCT-derived BMD is still more sensitive for determining variability in Ca concentration, compared with DEXA-derived BMD adjusted for femur length. (Am J Vet Res2004;65:891–900)
Investigation of the facilitation of the nociceptive withdrawal reflex evoked by repeated transcutaneous electrical stimulations as a measure of temporal summation in conscious horses
Authors: Spadavecchia Claudia , Andersen Ole K. , Arendt-Nielsen Lars , Spadavecchia Luciano , Doherr Marcus , Schatzmann Urs 
Published: December 2005

Abstract

Objective—To investigate whether facilitation of the
nociceptive withdrawal reflex (NWR) can be evoked
and quantified as a measure of temporal summation
from the distal aspect of the left forelimb and hind
limb in standing nonsedated horses via repeated
stimulations of various subthreshold intensities and
frequencies.

Animals—10 adult horses.

Procedure—Surface electromyographic activity
evoked by stimulation of the digital palmar and plantar
nerves was recorded from the common digital
extensor and cranial tibial muscles. For each horse,
the NWR threshold intensity to a single stimulus was
determined for the forelimb and hind limb. Repeated
stimulations were performed at subthreshold intensities
and at frequencies of 2, 5, and 10 Hz. The reflex
amplitude was quantified, and the behavioral responses
accompanying the stimulations were scored.

Results—Repeated stimulations at subthreshold
intensities were able to summate and facilitate the
NWR in conscious horses. The reflex facilitation was
significantly related to the intensity of the repeated
stimuli, whereas no effect of stimulation frequency
was found. Reaction scores increased significantly for
increasing stimulation intensities.

Conclusions and Clinical Relevance—Temporal summation
obtained by repeated stimulations of subthreshold
intensity appears to represent a new tool for
investigating nociceptive pathophysiologic processes
in horses; this experimental model may be useful to
examine the mode of action and efficacy of analgesic
and anesthetic interventions and possibly to assess
sensory dysfunction in clinical settings. (Am J Vet Res 2004;65:901–908)
Assessment of repeatability, reproducibility, and effect of anesthesia on determination of radial and longitudinal left ventricular velocities via tissue Doppler imaging in dogs
Authors: Chetboul Valerie , Athanassiadis Nicolas , Carlos Carolina , Nicolle Audrey , Zilberstein Luca , Pouchelon Jean-Louis , Lefebvre Herve P. , Concordet Didier 
Published: December 2005

Abstract

Objective—To determine left ventricular free wall
(LVFW) motions and assess their intra- and interday
variability via tissue Doppler imaging (TDI) in healthy
awake and anesthetized dogs.

Animals—6 healthy adult Beagles.

Procedure—In the first part of the study, 72 TDI
examinations (36 radial and 36 longitudinal) were performed
by the same observer on 4 days during a 2-week period in all dogs. In the second part, 3 dogs
were anesthetized with isoflurane and vecuronium.
Two measurements of each TDI parameter were
made on 2 consecutive cardiac cycles when ventilation
was transiently stopped. The TDI parameters
included maximal systolic, early, and late diastolic
LVFW velocities.

Results—The LVFW velocities were significantly higher
in the endocardial than in the epicardial layers and
also significantly higher in the basal than in the midsegments
in systole, late diastole, and early diastole.
The intraday coefficients of variation (CVs) for systole
were 16.4% and 22%, and the interday CV values were
11.2% and 16.4% in the endocardial and epicardial layers,
respectively. Isoflurane anesthesia significantly
improved the intraday CV but induced a decrease in
LVFW velocities, except late diastolic in endocardial layers
and early diastolic in epicardial layers.

Conclusions and Clinical Relevance—Left ventricular
motion can be adequately quantified in dogs and
can provide new noninvasive indices of myocardial
function. General anesthesia improved repeatability
of the procedure but cannot be recommended
because it induces a decrease in myocardial velocities.
(Am J Vet Res 2004;65:909–915)
Comparison of hematologic values and transforming growth factor-β and insulin-like growth factor concentrations in platelet concentrates obtained by use of buffy coat and apheresis methods from equine blood
Authors: Sutter W. Wesley , Kaneps Andris J. , Bertone Alicia L. 
Published: December 2005

AbstractObjective—To evaluate the buffy coat and apheresis methods for preparation of platelet concentrates from equine blood by comparing platelet and growth factor concentrations.Animals—15 mature mixed-breed geldings.Procedure—Whole blood samples were collected and processed by use of a buffy coat or apheresis method to obtain platelet poor and platelet concentrated fractions. The PCV, WBC count, and platelet count were compared among whole blood samples, platelet poor fractions, concentrates obtained by use of the apheresis method (ie, apheresis platelet concentrates), and concentrates obtained by use of the buffy coat method (ie, buffy coat platelet concentrates). Concentrations of transforming growth factor- β (ie, TGF-β1 and TGF-β2) and insulin-like growth factor were compared between buffy coat and apheresis platelet concentrates.Results—Platelet concentrations were 8.9-fold and 5.2-fold greater in buffy coat and apheresis platelet concentrates, respectively, compared with whole blood. Platelet concentrations were 13.1-fold greater in filtered apheresis platelet concentrates, compared with whole blood. TGF-β1 concentrations were 2.8- fold and 3.1-fold greater in buffy coat and apheresis platelet concentrates, respectively, and TGF-β1 concentrations were 10.5-fold greater in filtered apheresis platelet concentrates, compared with whole blood. TGF-β2 concentrations were 3.6-fold greater in apheresis platelet concentrates, compared with whole blood. Platelet concentrations correlated with growth factor concentrations across all blood and platelet fractions. White blood cell counts had a significant positive correlation with TGF-β1 concentration in buffy coat platelet concentrates.Conclusions and Clinical Relevance—Platelets and TGF-β1 can be concentrated reliably from equine blood by use of buffy coat or apheresis methods, without modification of the protocols used for humans. (Am J Vet Res2004;65:924–930)
Investigation of the expression and localization of glucose transporter 4 and fatty acid translocase/CD36 in equine skeletal muscle
Authors: van Dam Klien G. , van Breda Eric , Schaart Gert , van Ginneken Mireille M. E. , Wijnberg Inge D. , de Graaf-Roelfsema Ellen , van der Kolk Johannes H. , Keizer Hans A. 
Published: December 2005

Abstract

Objective—To investigate the expression and localization
of glucose transporter 4 (GLUT4) and fatty acid
translocase (FAT/CD36) in equine skeletal muscle.

Sample Population—Muscle biopsy specimens
obtained from 5 healthy Dutch Warmblood horses.

Procedures—Percutaneous biopsy specimens were
obtained from the vastus lateralis, pectoralis descendens,
and triceps brachii muscles. Cryosections were
stained with combinations of GLUT4 and myosin
heavy chain (MHC) specific antibodies or FAT/CD36
and MHC antibodies to assess the fiber specific
expression of GLUT4 and FAT/CD36 in equine skeletal
muscle via indirect immunofluorescent
microscopy.

Results—Immunofluorescent staining revealed that
GLUT4 was predominantly expressed in the cytosol
of fast type 2B fibers of equine skeletal muscle,
although several type 1 fibers in the vastus lateralis
muscle were positive for GLUT4. In all muscle fibers
examined microscopically, FAT/CD36 was strongly
expressed in the sarcolemma and capillaries. Type 1
muscle fibers also expressed small intracellular
amounts of FAT/CD36, but no intracellular FAT/CD36
expression was detected in type 2 fibers.

Conclusions and Clinical Relevance—In equine
skeletal muscle, GLUT4 and FAT/CD36 are expressed
in a fiber type selective manner. ( Am J Vet Res 2004;65:951–956)