Qualitative behavioural assessment (QBA) is based on observers' ability to capture the dynamic complexity of an animal's demeanour as it interacts with the environment, in terms such as tense, anxious or relaxed. Sensitivity to context is part of QBA's integrative capacity and discriminatory power; however, when not properly managed it can also be a source of undesirable variability and bias. This study investigated the sensitivity of QBA to variations in the visual or verbal information provided to observers, using free-choice profiling (FCP) methodology. FCP allows observers to generate their own descriptive terms for animal demeanour, against which each animal's expressions are quantified on a visual analogue scale. The resulting scores were analysed with Generalised Procrustes Analysis (GPA), generating two or more multi-variate dimensions of animal expression. Study 1 examined how 63 observers rated the same video clips of individual sheep during land transport, when these clips were interspersed with two different sets of video footage. Scores attributed to the sheep in the two viewing sessions correlated significantly (GPA dimension 1: rs=0.95, P<0.001, GPA dimension 2: rs=0.66, P=0.037) indicating that comparative rankings of animals on expressive dimensions were highly similar, however, their mean numerical scores on these dimensions had shifted (RM-ANOVA: Dim1: P<0.001, Dim2: P<0.001). Study 2 investigated the effect of being given different amounts of background information on two separate groups of observers assessing footage of 22 individual sheep in a behavioural demand facility. One group was given no contextual information regarding this facility, whereas the second group was told that animals were moving towards and away from a feeder (in view) to access feed. Scores attributed to individual sheep by the two observer groups correlated significantly (Dim1: rs=0.92, P<0.001, Dim2: rs=0.52, P=0.013). A number of descriptive terms were generated by both observer groups and used in similar ways, other terms were unique to each group. The group given additional information about the experimental facility scored the sheep's behaviour as more 'directed' and 'focused' than observers who had not been told. Thus, in neither of the two studies did experimentally imposed variations in context alter the characterisations of animals relative to each other, but in Study 1 this did affect the mean numerical values underlying these characterisations, indicating a need for careful attention to the use of visual analogue scales.
Qualitative behavioural assessment (QBA) has been used to quantify the expressive behaviour of animals, and operant tests have been used to quantify measures of behavioural need. In this study we compared measures of behavioural expression and behaviour in operant tests. We examined the behavioural expression of pregnant ewes of body condition score (BCS) 2 and 3. The ewes were exposed to a feed motivation test in which they received a food reward. Pregnant ewes (48–70 days gestation) were assessed during a food motivation test after they had been maintained at BCS 3 (n = 7) or given a decreasing plane of nutrition that resulted in slow loss of 1 BCS unit (over 10–12 weeks; n = 7) or a fast loss of 1 BCS unit (over 4–6 weeks; n = 7). The feed motivation test involved ewes having the opportunity to approach a food reward and then being moved a given distance away from the reward by an automatic gate; they could then subsequently return to the feeder. Continuous video footage of each ewe during one cycle of the gate (approaching and returning from the food reward) was shown in random order to 11 observers who used their own descriptive terms (free-choice profiling methodology; FCP) to score the animals using QBA. Data of the assessment were analysed with generalised Procrustes analysis (GPA), a multivariate statistical technique associated with FCP. The research group also quantified the feeding behaviour of sheep in the same clips. These behaviours included how sheep approached the feeder, behaviours exhibited at the feeder, and how sheep returned from the feeder. There was consensus amongst observers in terms of their assessment of behavioural expression of the sheep (P < 0.001). The GPA found three main dimensions of assessed behavioural expression in the sheep, which together explained 44% of the variation observed. GPA dimension 1 differed between the three treatment groups (P < 0.05): ewes maintained at BCS 3 scored low on GPA dimension 1 (i.e. were described as more calm/bored/comfortable) compared with ewes that had a slow declining BCS (described as more interested/anxious/excited). GPA dimension 2 scores were not significantly different between treatment groups. However, quantitative behaviours exhibited by sheep during the clips were correlated with qualitative behavioural assessments made by the observers. Animals that spent more time ‘sniffing and looking for more feed’ were attributed lower GPA 2 scores (described as more hungry/searching/excited) (P < 0.05), and animals that ‘did not walk directly to the food reward (but stopped along the way)’ were attributed significantly higher GPA 2 scores (more curious/intimidated/uneasy) (P < 0.01). GPA dimension 3 scores also did not differ between the treatment groups; however, sheep that had a higher number of feeding events during the entire 23-h feed motivation test were attributed lower GPA dimension 3 scores (they were described as more hungry/bold/interested) (P < 0.05), and sheep that consumed a larger amount of the feed reward were attributed higher GPA dimension 3 scores (more curious/concerned/reserved) (P < 0.05). We conclude that QBA is a valuable method of assessing sheep behavioural expression under the conditions tested, in that it provided an integrative characterisation of sheep behavioural expression that was in agreement with quantitative behavioural measures of feeding.