Measuring ketones in the field: rapid and reliable measures of β‐hydroxybutyrate in birds

Abstract

Ketone bodies such as β‐hydroxybutyrate are important indicators of metabolic condition in birds and are linked to a suite of ecologically relevant factors including migratory decision‐making, hunger level and ectoparasite load. Portable point‐of‐care (POC) devices designed to measure ketones in humans offer a cheap and easy solution to field physiologists in comparison with previous laboratory methods; however, their accuracy for use in birds has received scant attention. Here, we assessed the accuracy of a POC ketone meter (FreeStyle Precision Neo, Abbott, IL, USA) using samples from intermittently fed Red Junglefowl Gallus gallus. Although the device overestimated ketone levels in comparison with laboratory‐derived values, random error was low and laboratory vs. device values correlated well, indicating that the Precision Neo is of sufficient accuracy for use in the field and is a pragmatic choice for avian physiologists.