Effect of body size on gastric emptying using the 13C-octanoic acid breath test

The C-13-octanoic acid breath test (OABT) may be a useful non-invasive method for assessing the rate of gastric emptying in dogs. The aim of this study was to determine whether an association exists between body size and rate of gastric emptying in dogs. Fifty-five dogs ranging from 6 to 39 kg were recruited and rate of gastric emptying was assessed using the OABT. The time to peak (CO2)-C-13 excretion (t(max)) and half-dose recovery time (t(1/2)) were calculated. The OABT was simple to perform and well tolerated by the. dogs. Mean (sd) t(max) was 2(.)67 hours (0(.)6) and mean t(1/2) was 3(.)38 hours (0(.)79). Inter-individual variation in the rate of gastric emptying was 23(.)3 per cent for t(1/2) and 22(.)5 per cent for t(max). No association was detected between the rate of gastric emptying and body surface area, mass, age, sex or test operator. The OABT may be a useful non-invasive and non-radioactive test for assessment of the rate of gastric emptying in dogs in clinical practice.