Objective—To assess accuracy and reliability of
open-flow indirect calorimetry in dogs.
Animals—13 clinically normal dogs.
Procedure—In phase 1, oxygen consumption per
kilogram of body weight (VO2kg) was determined in 6
anesthetized dogs by use of open-flow indirect
calorimetry before and after determination of VO2/kg
by use of closed-circuit spirometry. In phase 2, four
serial measurements of VO2 and carbon dioxide production
(VCO2) were obtained in 7 awake dogs by use
of indirect calorimetry on 2 consecutive days. Resting
energy expenditure (REE) was calculated.
Results—Level of clinical agreement was acceptable
between results of indirect calorimetry and spirometry.
Mean VO2/kg determined by use of calorimetry
before spirometry was significantly greater than that
obtained after spirometry. In phase 2, intraclass correlation
coefficients (ICC) for REE and VO2 were 0.779
and 0.786, respectively, when data from all 4 series
were combined. When the first series was discounted,
ICC increased to 0.904 and 0.894 for REE and VO2,
respectively. The most reliable and least variable measures
of REE and VO2 were obtained when the first 2
series were discounted.
Conclusions and Clinical Relevance—Open-flow
indirect calorimetry may be used clinically to obtain a
measure of VO2 and an estimate of REE in dogs. Serial
measurements of REE and VO2 in clinically normal
dogs are reliable, but a 10-minute adaption period
should be allowed, the first series of observations
should be discounted, multiple serial measurements
should be obtained, and REE. (Am J Vet Res
Objective—To determine the level of clinical agreement
between 2 methods for the measurement of
resting energy expenditure (REE).
Design—Prospective case series.
Procedure—Oxygen consumption (O2) and CO2 production
(CO2) were measured with an open-flow indirect
calorimeter in healthy (n = 10) and ill (67) dogs.
Measurements were collected at 3 time periods on 2
days. The O2 and the CO2 measurements were then
used to calculate the REE values.
Results—Mean values of measured (MREE) and
predicted (PREE) REEs in healthy dogs and a dog
with medical illnesses or trauma were not significantly
different. There was a significant difference
on day 2 between the MREE and PREE in the group
of dogs recovering from major surgery. More importantly,
there was significant variation between the
PREE and MREE on an individual-dog basis. The
PREE only agreed to within ± 20% of the MREE in
51% to 57% of the dogs.
Conclusions and Clinical Relevance—The level of
agreement between these two methods for determining
the 24-hour REE was poor in individual dogs.
The level of disagreement between the 2 methods
indicates that these methods may not be used interchangeably
in a clinical setting. Measurement of REE
by use of indirect calorimetry may be the only reliable
method of determining REE in an individual ill or
healthy dog. (J Am Vet Med Assoc 2004;225:58–64)
Objective—To compare ocular structures of Quarter Horses homozygous for hereditary equine regional dermal asthenia (HERDA) with those of Quarter Horses not affected by HERDA (control horses) and to determine the frequency of new corneal ulcers for horses with and without HERDA during a 4-year period.
Design—Cohort study of ocular structures and retrospective case series of horses with and without HERDA.
Animals—The cohort portion of the study involved 10 Quarter Horses with HERDA and 10 Quarter Horses without HERDA; the retrospective case series involved 28 horses with HERDA and 291 horses without HERDA.
Procedures—Ophthalmic examinations, Schirmer tear tests, tonometry, corneal pachymetry, histologic examinations, and scanning electron microscopy (SEM) were performed in cohorts of Quarter Horses with and without HERDA. Records were reviewed to determine the incidence of corneal ulcers in horses with and without HERDA during a 4-year period.
Results—Corneal thickness of horses with HERDA was significantly less than that of control horses, but tear production of horses with HERDA was significantly greater than that of control horses. Results of SEM revealed zones of disorganized, haphazardly arranged collagen fibrils in corneas of horses with HERDA that were not evident in corneas of control horses. The incidence of corneal ulcers was significantly greater for horses with HERDA than for horses without HERDA during the 4-year period.
Conclusions and Clinical Relevance—Alterations in corneal thickness, arrangement of collagen fibers, and incidence of corneal ulcers indicated that abnormalities in horses with HERDA were not limited to the skin.
Objective—To identify clinical, echocardiographic,
and electrocardiographic abnormalities in Boxers with
cardiomyopathy and echocardiographic evidence of
left ventricular systolic dysfunction.
Animals—48 mature Boxers.
Procedure—Medical records were reviewed for information
on age; sex; physical examination findings;
and results of electrocardiography, 24-hour ambulatory
electrocardiography, thoracic radiography, and
Results—Mean age of the dogs was 6 years (range, 1
to 11 years). Twenty (42%) dogs had a systolic murmur,
and 9 (19%) had ascites. Congestive heart failure was
diagnosed in 24 (50%) dogs. Seventeen (35%) dogs
had a history of syncope. Mean fractional shortening
was 14.4% (range, 1% to 23%). Mean left ventricular
systolic and diastolic diameters were 4.5 cm (range, 3
to 6.3 cm) and 5.3 cm (range, 3.9 to 7.4 cm), respectively.
Twenty-eight (58%) dogs had a sinus rhythm
with ventricular premature complexes (VPCs), and 20
had supraventricular arrhythmias (15 with atrial fibrillation
and 5 with sinus rhythm and atrial premature complexes).
Sixteen of the dogs with supraventricular
arrhythmias also had occasional VPCs. Morphology of
the VPCs seen on lead II ECGs was consistent with left
bundle branch block in 25 dogs, right bundle branch
block in 8, and both in 11.
Conclusions and Clinical Relevance—Results suggest
that Boxers with cardiomyopathy and left ventricular
dysfunction frequently have arrhythmias of supraventricular
or ventricular origin. Whether ventricular dysfunction
was preceded by electrical disturbances could
not be determined from these data, and the natural history
of myocardial disease in Boxers requires further
study. (J Am Vet Med Assoc 2005;226:1102–1104)
Objective—To evaluate anesthetic effects of 4 drug
combinations used for total intravenous anesthesia of
horses undergoing surgical removal of an abdominal
Animals—32 healthy cryptorchid horses.
Procedure—Horses were sedated with xylazine and
butorphanol and were randomly assigned to 1 of 4
groups: induction of anesthesia with ketamine and
diazepam and maintenance with bolus administration
of ketamine and xylazine (KD/KX); induction and maintenance
of anesthesia with bolus administration of
tiletamine-zolazepam, ketamine, and detomidine
(TKD); induction and maintenance of anesthesia with
continuous infusion of xylazine, guaifenesin, and ketamine;
and induction and maintenance of anesthesia
with continuous infusion of guaifenesin and thiopental.
Horses that moved 3 consecutive times in
response to surgical stimulation or for which surgery
time was > 60 minutes were administered an inhalant
anesthetic, and data from these horses were excluded
Results—Quality of induction was not significantly
different among groups. Muscle relaxation and analgesia
scores were lowest for horses given KD/KX, but
significant differences among groups were not
detected. Horses anesthetized with TKD had a significantly
greater number of attempts to stand, compared
with the other groups, and mean quality of
recovery from anesthesia for horses in the TKD group
was significantly worse than for the other groups.
Anesthesia, surgery, and recovery times were not significantly
different among groups.
Conclusions and Clinical Relevance—Results suggest
that all 4 drug combinations can be used to
induce short-term anesthesia for abdominal cryptorchidectomy
in horses. However, horses receiving
TKD had a poorer recovery from anesthesia, often
requiring assistance to stand. (J Am Vet Med Assoc