Validating the use of qualitative behavioral assessment as a measure of the welfare of sheep during transport.

We tested the application of qualitative behavioral assessment (QBA) as a welfare assessment tool. Sheep were exposed to road transport treatments, and behavioral expressions were compared between experimental treatments and validated by correlation with physiological measures. We compared journeys differing in ventilation (closed vs. open-sided trailer), flooring (grip vs. nongrip flooring), and driving styles (stop-start vs. continuous driving). Blood samples were collected immediately before loading and after unloading; heart rate and core body temperatures were recorded continuously. Continuous video footage was edited to show individual sheep to observers for QBA using free-choice profiling (observers used their own descriptive terms). There was significant consensus in observers' scores for the sheep in each experiment (p < .001). Observers distinguished between sheep exposed to flooring (p = .014) or driving-style (p = .005) treatments, but not between ventilation treatments. QBA scores were compared (p < .05) with plasma leptin, glucose, and insulin-like growth factor-1 concentrations; white blood cell profiles; red blood cell counts; hematocrit; body temperatures; and heart rate variability. Observer assessments reflected treatment differences, and correlations between behavioral expression and physiological responses were found.