Comparison of barium sulphate and iohexol for gastrointestinal transit time in Barn owls (Tyto alba).

Abstract

Background: The aim of the study is to compare gastrointestinal (GI) transit times and evaluate the adequacy of radiographic opacification of barium sulphate (BaSO₄) and iohexol in Barn owls (Tyto alba). Eight healthy juvenile owls were included in a randomized crossover study with a 5-day washout period. BaSO₄ (30% w/v) and iohexol (300 mg I/ml, undiluted) were administered in a randomized order to prevent order effects and were administered via orogastric tube at a dosage of 25 ml/kg. Serial radiographs were obtained at specific intervals for up to 300 min. Three independent observers evaluated the images for transit times using a time-blinded protocol.

Results: Total transit time (esophagus to cloaca) was significantly shorter for iohexol (5.0 ± 0.0 min) compared to BaSO₄ (15.0 ± 8.4 min) (p = 0.039). Both agents provided adequate radiopacity for clear anatomic differentiation. No adverse effects or contrast-related complications were observed.

Conclusions: Limitations of this study include the small sample size (n = 8) and the use of static radiography rather than fluoroscopy, which precluded real-time motility assessment. Iohexol is a safe and significantly faster alternative to BaSO₄ for GI contrast studies in Barn owls. It is particularly advantageous in emergency cases requiring rapid diagnosis or involving suspected GI perforation.