Objective—To determine whether mild restriction of
food intake affects clinicopathologic variables, body
composition, and performance of dogs undertaking
intense sprint exercise.
Animals—9 trained healthy adult Greyhounds.
Procedure—Dogs were offered food free choice
once daily for 9 weeks until body weight and food
intake stabilized. Dogs were then randomly assigned
to be fed either 85% or 100% of this quantity of food
in a crossover study (duration of each diet treatment
period, 9 weeks). Dogs raced a distance of 500 m
twice weekly. Clinicopathologic variables were
assessed before and 5 minutes after racing; food
intake, weight, body composition, body condition
score, and race times were compared at the end of
each diet period.
Results—Compared with values associated with
unrestricted access to food, there were significant
decreases in mean body weight (by 6%) and median
body condition score (from 3.75 to 3.5 on a 9-point
scale) and the mean speed of the dogs was significantly
faster (by 0.7 km/h) when food intake was
restricted. Body composition and most clinicopathologic
variables were unaffected by diet treatment, but
dogs given restricted access to food had slightly
fewer neutrophils, compared with values determined
when food intake was unrestricted.
Conclusions and Clinical Relevance—Results indicate
that the common practice among Greyhound
trainers of mildly restricting food intake of racing dogs
to reduce body weight does improve sprint performance.
A body condition score of approximately 3.5
on a 9-point scale is normal for a trained Greyhound in
racing condition. (Am J Vet Res 2005;66:1065–1070)
Procedure—Dogs were randomly assigned to 2
groups of 3 dogs in a crossover design. Diazepam
(0.5 mg/kg of body weight) was administered intravenously
to dogs in group 1 and intranasally to dogs
in group 2. Blood was collected from the jugular vein
of each dog into tubes containing lithium heparin
before and 3, 6, 9, 12, 15, 20, 30, 60, 120, 240, and
480 minutes following diazepam administration. After
a 4-day washout period, dogs in group 1 received
diazepam intranasally, dogs in group 2 received
diazepam intravenously, and blood was again collected.
Plasma concentration of BDZ was determined by
use of a fluorescence polarization immunoassay.
Results—Mean (± SD) peak plasma concentration of
BDZ following IV administration (1316 ± 216 µg/L)
was greater than that following IN administration
(448 ± 41 µg/L). Time to peak concentration was ≤ 3
minutes following IV administration and 4.5 ± 1.5
minutes following IN administration. Mean bioavailability
of BDZ following IN administration was
80 ± 9%.
Conclusions and Clinical Relevance—Diazepam is
rapidly and efficiently absorbed following IN administration
of the parenteral formulation. Plasma concentrations
match or exceed the suggested therapeutic
concentration (300 µg/L). Intranasal administration of
diazepam may be useful for treatment of seizures in
dogs by owners or when intravenous access is not
readily available. (Am J Vet Res 2000;61:651–654)