Changes in gallbladder volume in healthy dogs after food was withheld for 12 hours followed by ingestion of a meal or a meal containing erythromycin.
OBJECTIVE
To assess the influence of meal ingestion and orally administered erythromycin on gallbladder volume in dogs.


METHODS
22 healthy dogs.


METHODS
Ultrasonographically determined gallbladder dimensions in unsedated dogs were used to calculate volume. Measurements were recorded after food was withheld for 12 hours (time 0) and 15, 30, 45, 60, 90, and 120 minutes after a 100-g meal without (n = 22) or with erythromycin (1.0 mg/kg [7], 2.5 mg/kg [7], and both dosages [8]). Gallbladder ejection fraction represented the percentage of volume change from time 0. Intraday and interday coefficients of variation determined operator repeatability and physiologic variation.


RESULTS
We did not detect significant differences in gallbladder volume per unit of body weight between treatments at time 0 or in ejection fraction percentage within or between treatments. Median time 0 gallbladder volume was 0.6 mL/kg (range, 0.4 to 1.9) but was > 1.0 mL/kg in 3 of 22 (14%) dogs and <or= 1.0 mL/kg in 19 of 22 (86%) dogs. Twenty dogs achieved an ejection fraction >or= 25% with at least 1 treatment, but 2 dogs with a gallbladder volume <or= 1.0 mL/kg at time 0 did not. Intraday and interday coefficients of variation were 18% and 25%, respectively.


CONCLUSIONS
Gallbladder volume <or= 1.0 mL/kg at time 0 and ejection fraction >or= 25% were typical. No treatment consistently induced greater gallbladder contraction. Dogs with a gallbladder volume > 1.0 mL/kg and ejection fraction < 25% may require a combined meal and erythromycin protocol.
Ramstedt
Keri L
KL
Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA.
Center
Sharon A
SA
Randolph
John F
JF
Yeager
Amy E
AE
Erb
Hollis N
HN
Warner
Karen L
KL
D000818:Animals; D004285:Dogs / Q000502:physiology*; D004435:Eating / Q000502:physiology*; D004917:Erythromycin / Q000008:administration & dosage*; D005215:Fasting; D005260:Female; D005704:Gallbladder / Q000033:anatomy & histology / Q000000981:diagnostic imaging / Q000187:drug effects / Q000502:physiology*; D005765:Gastrointestinal Agents / Q000008:administration & dosage*; D008297:Male; D009037:Motilin / Q000502:physiology; D009119:Muscle Contraction / Q000502:physiology; D018709:Statistics, Nonparametric; D014463:Ultrasonography
D005765:Gastrointestinal Agents; D009037:Motilin; D004917:Erythromycin