The effect of feeding on serum concentrations of cobalamin, folate, trypsin-like immunoreactivity, and pancreatic lipase immunoreactivity in dogs with signs of chronic gastrointestinal disease.

Abstract

BACKGROUND: It is unknown if serum concentrations of cobalamin, folate, canine pancreatic lipase immunoreactivity (cPLI), and canine trypsin-like immunoreactivity (cTLI) obtained postprandially are equivalent to measurements obtained after withholding food in dogs with suspected gastrointestinal disease. HYPOTHESIS/OBJECTIVES: Measurements of serum concentrations of cobalamin, folate, cPLI, and cTLI postprandially will be equivalent to measurements after 12&#x2009;hours of withholding food in dogs with signs of chronic gastrointestinal disease. Changes observed will not alter clinical interpretation. ANIMALS: 51 client-owned dogs with signs of gastrointestinal disease. METHODS: Prospective single arm clinical trial. Serum concentrations of cobalamin, folate, cPLI and cTLI 2, 4, and 8&#x2009;hours postprandially were compared by equivalence testing to values after withholding food for 12&#x2009;hours (baseline). RESULTS: Mean serum cobalamin concentrations 2&#x2009;hours (498.1&#x2009;&#xb1;&#x2009;213.1&#x2009;ng/L; P&#x2009;=&#x2009;0.024) and 4&#x2009;hours (501.9&#x2009;&#xb1;&#x2009;207.4&#x2009;ng/L; P&#x2009;=&#x2009;0.008) postprandial were equivalent to baseline (517.3&#x2009;&#xb1;&#x2009;211.5&#x2009;ng/L). Mean serum cTLI 2&#x2009;hours (31.3&#x2009;&#xb1;&#x2009;14&#x2009;&#x3bc;g/L; P&#x2009;<&#x2009;0.001) and 4&#x2009;hours (29.6&#x2009;&#xb1;&#x2009;13.1&#x2009;&#x3bc;g/L; P&#x2009;=&#x2009;0.027) postprandial were equivalent to baseline (31.1&#x2009;&#xb1;&#x2009;15&#x2009;&#x3bc;g/L). Mean serum folate concentration 2&#x2009;hours postprandial (15&#x2009;&#xb1;&#x2009;7.7&#x2009;&#x3bc;g/L) was equivalent to baseline (13.7&#x2009;&#xb1;&#x2009;8.3&#x2009;&#x3bc;g/L; P&#x2009;<&#x2009;0.001). Equivalence could not be assessed for cPLI due to results below the lower limit of quantification. Feeding altered the clinical interpretation in 27% (cobalamin), 35% (folate), 20% (cTLI), and 12% (cPLI) of dogs. CONCLUSIONS AND CLINICAL IMPORTANCE: The clinical interpretation for a substantial number of samples changed after feeding, therefore withholding food before sample collection is prudent.