Application of the lactose ¹³C-ureide breath test for measurement of equine orocaecal transit time

Sutton, D.G.M. , Preston, T. and Love, S. (2011) Application of the lactose ¹³C-ureide breath test for measurement of equine orocaecal transit time. Equine Veterinary Journal, 43(S39), pp. 49-55. (doi: 10.1111/j.2042-3306.2011.00407.x)

Abstract

<b>Reasons for performing study:</b> Application of the lactose ¹³C-ureide breath test (LUBT) for measurement of equine orocaecal transit time (OCTT) has not been reported previously. The ability to assess OCTT noninvasively, and to investigate its relationship to gastric emptying rate and small intestinal transit, would be of both clinical and research value.<p></p> <b>Objectives:</b> 1) Assessment of the LUBT in healthy horses, with comparison of induced versus noninduced test protocols. 2) Application of a new dual stable isotope breath test (lactose ¹³C-ureide and ¹³C-octanoic acid) for gastrointestinal transit measurement.<p></p> <b>Hypothesis:</b> The LUBT will allow quantification of equine OCTT, and test efficacy will be enhanced by prior administration of lactose ¹²C-ureide as shown in vitro. The dual tracer breath test will permit simultaneous measurement of gastric emptying, OCTT and small bowel transit times.<p></p> <b>Methods:</b> Induced and noninduced LUBTs were performed in 3 healthy mature horses in randomised order using a standard test meal and protocol. Combined LUBT and ¹³C-octanoic acid breath tests (¹³C-OABT) were performed in 4 individuals on 4 occasions at weekly intervals. Expiratory isotopic recovery was modelled to allow generation of gastric emptying data, small bowel transit times and caecal transit parameters.<p></p> <b>Results:</b> The induction protocol for the LUBT increased the rate and magnitude of expiratory ¹³CO₂ significantly. Mean ± s.d. values for OCTT, caecal lag phase (t_lag) and caecal t_1/2 using the induced LUBT were 3.24 ± 0.65 h, 5.62 ± 1.22 h and 6.31 ± 1.21 h, respectively. Dual stable isotope tests resulted in the production of 2 discrete peaks in expiratory ¹³CO₂ in 15/16 tests from which gastric t_1/2, OCTT and small bowel transit (SBT) parameters could be calculated.<p></p> <b>Conclusions:</b> The induced LUBT provides a reliable noninvasive measure of equine OCTT and can be paired with the ¹³C-OABT to provide further information about small intestinal motility.<p></p>

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Preston, Professor Tom and Love, Professor Sandy and Sutton, Professor David
• Authors: Sutton, D.G.M., Preston, T., and Love, S.
• College/School: College of Science and Engineering > Scottish Universities Environmental Research Centre; College of Medical Veterinary and Life Sciences > School of Biodiversity, One Health & Veterinary Medicine
• Journal Name: Equine Veterinary Journal
• ISSN: 0425-1644
• ISSN (Online): 2042-3306
• Published Online: 25 July 2011