Affective States In Animals Research Articles

You are How You Eat: Foraging Behavior as a Potential Novel Marker of Rat Affective State

Effective and safe foraging requires animals to behave according to the expectations they have about the rewards, threats, and costs in their environment. Since these factors are thought to be reflected in the animals’ affective states, we can use foraging behavior as a window into those states. In this study, rats completed a foraging task in which they had repeatedly to decide whether to continue to harvest a food source despite increasing time costs, or to forgo food to switch to a different food source. Rats completed this task across two experiments using manipulations designed to induce both positive and negative, and shorter- and longer- term changes in affective state: removal and return of enrichment (Experiment 1), implementation and reversal of an unpredictable housing treatment (Experiment 1), and delivery of rewards (tickling or sucrose) and punishers (air-puff or back-handling) immediately prior to testing (Experiment 2). In Experiment 1, rats completed fewer trials and were more prone to switching between troughs when housed in standard, compared to enriched, housing conditions. In Experiment 2, rats completed more trials following pre-test tickling compared to pre-test sucrose delivery. However, we also found that they were prone to disengaging from the task, suggesting they were really choosing between three options: ‘harvest’, ‘switch’, or ‘not work’. This limits the straightforward interpretation of the results. At present, foraging behavior within the context of this task cannot reliably be used as an indicator of an affective state in animals.

Animal affect, welfare and the Bayesian brain.

According to the Bayesian brain hypothesis, the brain can be viewed as a predictive machine, such that predictions (or expectations) affect how sensory inputs are integrated. This means that in many cases, affective responses may depend more on the subject's perception of the experience (driven by expectations built on past experiences) rather than on the situation itself. Little research to date has applied this concept to affective states in animals. The aim of this paper is to explore how the Bayesian brain hypothesis can be used to understand the affective experiences of animals and to develop a basis for novel predictions regarding animal welfare. Drawing from the literature illustrating how predictive processes are important to human well-being, and are often impaired in affective disorders, we explore whether the Bayesian brain theories may help understanding animals' affective responses and whether deficits in predictive processes may lead to previously unconsidered welfare consequences. We conclude that considering animals as predictive entities can improve our understanding of their affective responses, with implications for basic research and for how to provide animals a better life.

Tickling and its effects on the affective states of laying hens

Human-animal interactions may significantly influence the productivity and welfare of animals in the livestock industry. The nature of manipulation influences the physiology and behaviour of animals positively or negatively. To improve animal welfare, it is important to not only reduce unwanted negative states (fear, pain, suffering) but also to induce positive affective states in animals. Tickling has been described in multiple studies to evoke positive affective states in rats. We tested whether a similar form of tactile stimulation induces changes in the valence of affective states of laying hens using an operant judgement bias test. Sixteen laying hens housed in deep litter pens were divided into two groups with different forms of manipulation: a handled group (n = 8) or a tickled group (n = 8). First, the animals were trained to discriminate between the positive (PS, pecks rewarded with mealworms) and negative stimuli (NS, pecks punished with white noise) in a visual discrimination task (Go/NoGo). They were then subjected to the judgement bias test, in which responses to PS, NS and ambiguous middle stimulus (MS) were recorded. All hens successfully learned to discriminate between PS and NS. The treatment did not induce changes in judgement bias test performance. Tickling in the manner we administered it and applied in adulthood, did not appear to be perceived by hens as a positive event. The treatment did not affect judgement because the behavioural assay was not sensitive enough to detect a possible effect, or chickens did not find the tickling as administered to be positive enough. Perhaps the other more playful interactions with hens, a larger dosage or the treatment at an early period of life could have greater impact.

Judgement bias of group housed gestating sows predicted by behavioral traits, but not physical measures of welfare.

Judgement bias testing has emerged as a potential tool for assessing affective states in animals. Researchers infer an animal's affective state based on an animal's response to an ambiguous stimulus that is intermediate to both the rewarded and punished conditioned stimuli. Animals can be classified as "optimistic" or having a positive affective state if the animal displays behaviors that suggest an increased expectation of reward in the face of ambiguous stimuli. Alternatively, animals can be classified "pessimistic" or having a negative affective state if the animal displays behaviors that suggest an increased expectation of punishment in the face of ambiguous stimuli. Recent reports in multiple species question what factors influence performance in judgement bias testing, and which may allow for erroneous conclusions regarding individual affective state. In order to better understand this concern, 25 female swine were subjected to behavioral assessments at critical rearing stages to determine response variability. These same individuals were then assessed for physical measures of welfare and judgement bias using the "go/no-go" task as breeding adults. Sows which were more aggressive approached the ambiguous, but not the positive, stimulus significantly faster than others. Both optimistic and pessimistic biases were observed despite all sows living in enriched housing, and, sows with more positive physical welfare measures (fewer skin lesions and healthy body condition) did not exhibit more optimistic judgement biases. Our data demonstrate that behavior traits, such as aggressiveness, can affect a sow's performance in a judgement bias test, while measures of physical health did not. We suggest that individual differences in behavior (e.g., bold-aggressive behavioral syndrome, or, proactive coping style) generate different emotional responses and can contribute to the animal's overall affective state more so than physical ailment. Our findings highlight the complexity of how different factors impact an animal's overall affective state and support the need for complementary measures in future JBT studies, including personality assessment.

Cancer blues? A promising judgment bias task indicates pessimism in nude mice with tumors

In humans, affective states can bias responses to ambiguous information: a phenomenon termed judgment bias (JB). Judgment biases have great potential for assessing affective states in animals, in both animal welfare and biomedical research. New animal JB tasks require construct validation, but for laboratory mice (Mus musculus), the most common research vertebrate, a valid JB task has proved elusive. Here (Experiment 1), we demonstrate construct validity for a novel mouse JB test: an olfactory Go/Go task in which subjects dig for high- or low-value food rewards. In C57BL/6 and Balb/c mice faced with ambiguous cues, latencies to dig were sensitive to high/low welfare housing: environmentally-enriched animals responded with relative ‘optimism’ through shorter latencies. Illustrating the versatility of this validated JB task across different fields of research, it further allowed us to test hypotheses about the mood-altering effects of cancer in male and female nude mice (Experiment 2). Males, although not females, treated ambiguous cues as intermediate; and males bearing subcutaneous lung adenocarcinomas also responded more pessimistically to these than did healthy controls. To our knowledge, this is the first evidence of a valid mouse JB task, and the first demonstration of pessimism in tumor-bearing animals. This task still needs to be refined to improve its sensitivity. However, it has great potential for investigating mouse welfare, the links between affective state and disease, depression-like states in animals, and hypotheses regarding the neurobiological mechanisms that underlie affect-mediated biases in judgment.

Lateralized emotional functioning in domestic animals

The study of emotional functioning is of crucial importance for improving the welfare of domestic animals. The investigation of animal emotions is mainly based on the outcomes of affective states, specifically animal behaviour, physiology and cognition. The cognitive component of emotions includes the processes regulating the affective states in animals, which are lateralized in the animal kingdom. Functional asymmetries in emotional processing, indeed, have been widely reported in both vertebrates and invertebrates. To date, the study of animal emotions through the evaluation of cerebral lateralization has been mainly performed through the analysis of lateralized behaviours, which indirectly reflect the prevalent activation of the right or the left hemisphere. In particular, the asymmetric processing of different environmental stimuli through the different senses as well as the lateralized motor patterns have been associated with different aspects of animal emotions. In this review, we present a comprehensive overview of the behavioural asymmetries for the sensory and motor functions related to emotional functioning of domestic animals. Our final aim is to support the use of laterality as a tool to evaluate animal emotional processing, and therefore, their welfare.

Assessing Affective State in Laboratory Rodents to Promote Animal Welfare-What Is the Progress in Applied Refinement Research?

Simple SummaryIn the past, there was a strong focus on avoiding or reducing negative animal welfare in animal experimentation. Recently, the importance of promoting positive animal welfare in laboratory animals has been highlighted. To ensure and promote positive animal welfare, reliable methods to evaluate the animal’s emotional state are important. Important achievements have been made to assess pain and other negative states in animals in the last decades, and only recently have positive emotions been gaining more interest. Therefore, more methods allowing the assessment of emotional states in animals have been introduced. In this overview article, we present common and emerging methods to assess emotions in laboratory rodents. We focus on the use of these methods in applied refinement research to identify achieved progress as well as the potential of these tools to improve animal welfare in animal-based research and animal experimentation.An animal’s capacity to suffer is a prerequisite for any animal welfare concern, and the minimization of suffering is a key aim of refinement research. In contrast to the traditional focus on avoiding or reducing negative welfare states, modern animal welfare concepts highlight the importance of promoting positive welfare states in laboratory animals. Reliable assessments of affective states, as well as the knowledge of how to elicit positive affective states, are central to this concept. Important achievements have been made to assess pain and other negative affective states in animals in the last decades, but it is only recently that the neurobiology of positive emotions in humans and animals has been gaining more interest. Thereby, the need for promotion of positive affective states for laboratory animals is gaining more acceptance, and methods allowing the assessment of affective states in animals have been increasingly introduced. In this overview article, we present common and emerging methods to assess affective states in laboratory rodents. We focus on the implementation of these methods into applied refinement research to identify achieved progress as well as the future potential of these tools to improve animal welfare in animal-based research.

Relationships between play and responses to tickling in male juvenile rats

Play is a putatively positive experience and of key interest to the study of affective state in animals. Rats produce 50 kHz ultrasonic vocalisation (USVs) during positive experiences, including social play and tickling. The tickling paradigm is intended to mimic social play resulting in positively valanced ultrasonic vocalisation (USV) production. We tested two hypotheses on the relationship between tickling and play: that tickling would increase play behaviour or that play behaviour would increase in anticipation of tickling, and that tickling would share some specific properties of play (rebound and emotional contagion of unexposed cage mates). Male Wistar rats (N = 64, with 32 rats/cohort) of 28 days of age were housed in pairs with one rat assigned to be tickled and one as the non-tickled control. Production of 50 kHz USVs and hand-following behaviour was measured. Prior to handling, solitary and social play was recorded for 5 min in the home cage. A two-day break in tickling was used to assess a potential rebound increase in responses to tickling. Only one rat within each cage was handled to assess emotional contagion through changes in the behaviour of the cage-mate. Solitary but not social play increased prior to tickling relative to controls (p = 0.01). There were marked differences between cohorts; tickled rats in C2 produced less 50 kHz USVs than those in C1 (p = 0.04) and overall, C2 rats played less than rats in C1 (social p = 0.04 and solitary p < 0.001) and had a lighter start weight on arrival (p = 0.009) compared with cohort 1 (C1). In C1, there was evidence of rebound in USV production (p < 0.001) and a contagious effect of tickling reflected by increased hand-following in cage mates (p = 0.02). We found a positive relationship between start weight and USV responses to tickling (Rs = 0.43, p < 0.001), suggesting that the divergence in USV production may be due to developmental differences between cohorts. The results suggest that the relationship between tickling and play is complex in that tickling only affected solitary and not social play, and that tickling responses showed rebound and contagion effects on cage-mates which were specific to cohort responses to tickling.

The role of behavioural assessment in determining 'positive' affective states in animals.

Abstract The assessment and promotion of positive affective states as opposed to consideration of negative states alone has now become an accepted component of animal welfare thinking. However, methods for assessment of positive affective state are comparatively underdeveloped compared with their negative counterparts. Due to the current lack of established physiological methods for assessing positive effect in animals, behavioural measures are likely to be the closest proxies. In this paper, we broadly review spontaneous behavioural measures that have been utilized in mammals to determine positive affect. This includes luxury behaviours, facial expression, vocalizations and laterality. Play and anticipatory behaviours expressed in animals have received greatest research attention. However, these methods require care in interpretation due to the influence of age and other factors, such as social status on their performance. These methods may also be subjective if descriptions of individual behaviours are not well defined and validated. Methods that are amenable to automation may reduce subjectivity. Automation will also aid in more widespread implementation as an on-enterprise welfare assessment tool. There is a pressing need to develop simple and objective indices of positive affect. The use of vocalizations and facial expressions may fulfil these criteria. Future research attention should be directed towards further characterising these methods.

Tickling, a Technique for Inducing Positive Affect When Handling Rats.

Handling small animals such as rats can lead to several adverse effects. These include the fear of humans, resistance to handling, increased injury risk for both the animals and the hands of their handlers, decreased animal welfare, and less valid research data. To minimize negative effects on experimental results and human-animal relationships, research animals are often habituated to being handled. However, the methods of habituation are highly variable and often of limited effectiveness. More potently, it is possible for humans to mimic aspects of the animals' playful rough-and-tumble behavior during handling. When applied to laboratory rats in a systematic manner, this playful handling, referred to as tickling, consistently gives rise to positive behavioral responses. This article provides a detailed description of a standardized rat tickling technique. This method can contribute to future investigations into positive affective states in animals, make it easier to handle rats for common husbandry activities such as cage changing or medical/research procedures such as injection, and be implemented as a source of social enrichment. It is concluded that this method can be used to efficiently and practicably reduce rats' fearfulness of humans and improve their welfare, as well as reliably model positive affective states.

Tickling, a Technique for Inducing Positive Affect When Handling Rats

Handling small animals such as rats can lead to several adverse effects. These include the fear of humans, resistance to handling, increased injury risk for both the animals and the hands of their handlers, decreased animal welfare, and less valid research data. To minimize negative effects on experimental results and human-animal relationships, research animals are often habituated to being handled. However, the methods of habituation are highly variable and often of limited effectiveness. More potently, it is possible for humans to mimic aspects of the animals' playful rough-and-tumble behavior during handling. When applied to laboratory rats in a systematic manner, this playful handling, referred to as tickling, consistently gives rise to positive behavioral responses. This article provides a detailed description of a standardized rat tickling technique. This method can contribute to future investigations into positive affective states in animals, make it easier to handle rats for common husbandry activities such as cage changing or medical/research procedures such as injection, and be implemented as a source of social enrichment. It is concluded that this method can be used to efficiently and practicably reduce rats' fearfulness of humans and improve their welfare, as well as reliably model positive affective states.

Towards a more practical attention bias test to assess affective state in sheep.

Tests for attention bias potentially offer more rapid assessment of affective state in animals than existing cognitive methods. An attention bias test has previously been developed for sheep and validated as a measure of anxious states. The 3 minute test assessed behavioural responses of sheep in an enclosed arena after brief exposure to the threat of a dog. Experiment 1 of the current study aimed to refine the previously developed method, removing the need for a habituation period and shortening the test duration. Sheep were given either an anxiolytic drug, an anxiogenic drug or a control treatment prior to testing to induce contrasting affective states. Differences in behaviour were found between the treatment groups within the first 45s of the test, indicating the original test duration could be shortened from 180 s. During testing, 36 of 40 animals in the control and anxiolytic groups ate the novel feed offered in the test, indicating it is not necessary to habituate animals to a feed container. Experiment 2 aimed to confirm the responses measured in the test were primarily towards the dog rather than other aspects of the test environment. Sheep exposed to an empty window at the beginning of the test behaved differently to those which were exposed to a dog, indicating sheep behaviour in the test is at least partially a response to the dog. A third group of sheep were also tested with the dog immediately after having small data loggers attached to their necks. Behaviour of these sheep did not differ from the sheep tested without loggers, indicating data logger attachment did not impact their behaviour in the test. In both experiments, treatments did not appear to modify activity (zones crossed), which we propose indicates the test was primarily detecting valence of the affective state rather than arousal.

Judgement bias in pigs is independent of performance in a spatial holeboard task and conditional discrimination learning

Biases in judgement of ambiguous stimuli, as measured in a judgement bias task, have been proposed as a measure of the valence of affective states in animals. We recently suggested a list of criteria for behavioural tests of emotion, one of them stating that responses on the task used to assess emotionality should not be confounded by, among others, differences in learning capacity, i.e. must not simply reflect the cognitive capacity of an animal. We performed three independent studies in which pigs acquired a spatial holeboard task, a free choice maze which simultaneously assesses working memory and reference memory. Next, pigs learned a conditional discrimination between auditory stimuli predicting a large or small reward, a prerequisite for assessment of judgement bias. Once pigs had acquired the conditional discrimination task, optimistic responses to previously unheard ambiguous stimuli were measured in the judgement bias task as choices indicating expectation of the large reward. We found that optimism in the judgement bias task was independent of all three measures of learning and memory indicating that the performance is not dependent on the pig’s cognitive abilities. These results support the use of biases in judgement as proxy indicators of emotional valence in animals.

A shortened protocol for assessing cognitive bias in rats

BackgroundReliable measurement of affective state in animals is a significant goal of animal welfare. Such measurements would also improve the validity of pre-clinical mental health research which relies on animal models. However, at present, affective states in animals are inaccessible to direct measurement. In humans, changes in cognitive processing can give reliable indications of emotional state. Therefore, similar techniques are increasingly being used to gain proxy measures of affective states in animals. In particular, the ‘cognitive bias’ assay has gained popularity in recent years. Major disadvantages of this technique include length of time taken for animals to acquire the task (typically several weeks), negative experiences associated with task training, and issues of motivation. New methodHere we present a shortened cognitive bias protocol using only positive reinforcers which must actively be responded to. ResultsThe protocol took an average of 4days to complete, and produced similar results to previous, longer methods (minimum 30days). Specifically, rats housed in standard laboratory conditions demonstrated negative cognitive biases when presented with ambiguous stimuli, and took longer to make a decision when faced with an ambiguous stimulus. Comparison with existing methodsCompared to previous methods, this protocol is significantly shorter (average 4days vs. minimum 30days), utilises only positive reinforcers to avoid inducing negative affective states, and requires active responses to all cues, avoiding potential confounds of motivational state. ConclusionsWe have successfully developed a shortened cognitive bias protocol, suitable for use with laboratory rats.

Effects of a chronic stress treatment on vaccinal response in lambs

Farming systems can expose animals to chronic mild stress which is known to induce negative affective state. Affective state in animals, as in humans, can be assessed through behavioral cues. This study aimed to describe the effect of a chronic mild stress, known to induce a negative affective state, on sheep health through their response to vaccination. The study used 15 lambs subjected to a model of chronic mild stress for 15 weeks and 15 lambs reared under conventional farming as a control group. After 7 weeks of stressful treatment, the lambs were individually exposed to a judgment bias test to assess a putative stress-induced ‘pessimism.’ After 15 weeks of stressful treatment, antibody immune response was measured after an injection of a live vaccine challenge (Chlamydia abortus attenuated vaccine strain 1B). Stressed lambs displayed a pessimistic-like perception in the judgment bias test, revealing a negative affective state. Stressed and control animals showed different immunological reactions to vaccine challenge: stressed sheep had lower hemoglobin concentrations and higher platelet, granulocyte and acute-phase protein concentrations. Antibody response induced by the vaccine strain was not different between stressed and control sheep. Our results suggest that negative affective state induced by chronic stress treatment may induce a stronger inflammatory response to vaccine challenge in sheep. Improvement of animal health may be achieved through consideration of stressors that may affect the emotional and immunological state of sheep.

Sex differences in performance on a cognitive bias task in Norway rats

Cognitive biases, which are defined as distortions in cognitive processes that are influenced by a background emotional state, can provide information about an individual’s affective state. For instance, negative cognitive biases, where individuals assess ambiguous situations as unrewarding, are commonly found in humans suffering from anxiety disorders. Cognitive biases are also increasingly used as indicators of affective state in animals. As it is not clear whether female and male animals differ in performance on cognitive bias tasks, we used a spatial location task to examine cognitive bias in female and male adult Norway rats (Rattus norvegicus). We trained the rats to distinguish between reward and unrewarded locations, and then provided food pots at ambiguous, intermediate positions. We found that, during testing, females were slowest to approach the unrewarded location, while they approached ambiguous and rewarded locations similarly quickly. In contrast, the males approached all locations quickly. This sex difference is consistent with previous evidence that male rats are quicker than females to extinguish previously learned associations. Cognitive bias tasks could therefore be used to examine sex differences in learning strategies, as well as providing opportunities to test predictions about sex differences in welfare requirements.

Effects of stereotypic behaviour and chronic mild stress on judgement bias in laboratory mice

Cognitive processes are influenced by underlying affective states, and tests of cognitive bias have recently been developed to assess the valence of affective states in animals. These tests are based on the fact that individuals in a negative affective state interpret ambiguous stimuli more pessimistically than individuals in a more positive state. Using two strains of mice we explored whether unpredictable chronic mild stress (UCMS) can induce a negative judgement bias and whether variation in the expression of stereotypic behaviour is associated with variation in judgement bias. Sixteen female CD-1 and 16 female C57BL/6 mice were trained on a tactile conditional discrimination test with grade of sandpaper as a cue for differential food rewards. Once they had learned the discrimination, half of the mice were subjected to UCMS for three weeks to induce a negative affective state. Although UCMS induced a reduced preference for the higher value reward in the judgement bias test, it did not affect saccharine preference or hypothalamic–pituitary–adrenal (HPA) activity. However, UCMS affected responses to ambiguous (intermediate) cues in the judgement bias test. While control mice showed a graded response to ambiguous cues, UCMS mice of both strains did not discriminate between ambiguous cues and tended to show shorter latencies to the ambiguous cues and the negative reference cue. UCMS also increased bar-mouthing in CD-1, but not in C57BL/6 mice. Furthermore, mice with higher levels of stereotypic behaviour made more optimistic choices in the judgement bias test. However, no such relationship was found for stereotypic bar-mouthing, highlighting the importance of investigating different types of stereotypic behaviour separately.

How assessing relationships between emotions and cognition can improve farm animal welfare.

The assessment of farm animal welfare requires a good understanding of the animals' affective experiences, including their emotions. Emotions are transient reactions to short-term triggering events and can accumulate to cause longer-lasting affective states, which represent good or bad welfare. Cognition refers to the mechanisms by which animals acquire, process, store and act on information from the environment. The objective of this paper is to highlight the two-way relationships between emotions and cognition that were originally identified in human psychology, and to describe in what ways these can be used to better access affective experiences in farm animals. The first section describes a recent experimental approach based on the cognitive processes that the animal uses to evaluate its environment. This approach offers an integrative and functional framework to assess the animal's emotions more effectively. The second section focuses on the influence of emotions on cognitive processes and describes recently developed methodologies based on that relationship, which may enable an assessment of long-term affective states in animals. The last section discusses the relevance of behavioural strategies to improve welfare in animals by taking their cognitive skills into account. Specific cognitive processes eliciting positive emotions will be emphasised. Research into affective states of animals is progressing rapidly and the ability to scientifically access animal feelings should contribute to the development of innovative farming practices based on the animals' sentience and their cognitive skills in order to truly improve their welfare.

Negative affective states and their effects on morbidity, mortality and longevity

AbstractMortality rates are often used in population-level animal welfare assessments because they are assumed to reflect rates of disease or injury and other problems likely to cause poor welfare. High mortality is thus assumed to correlate with factors likely to cause negative affective states. Here, we argue that negative affective states are also related to mortality rates more directly, via causal rather than merely correlational routes. In humans, negative affective states predict elevated morbidity and mortality rates as well as decreased longevity, while self-reported happiness does the opposite. This review investigates whether mortality rates and longevity can thus be used to make inferences regarding past affective states in animals. The proposed mechanism is that chronic stressors cause negative affective states and thence harmful physiological consequences through continual activation of the hypothalamic-pituitary-adrenal and sympathetic-adreno-medullary axes, which in turn can lead to increased mortality. The convergent validity of mortality as an indicator of past negative affect is demonstrated via examples of how stressors such as bereavement in humans and social isolation in social non-human species cause negative affective states, and then increase the morbidity of potentially lethal conditions such as cardiovascular disease, cancer and HIV/AIDS, ultimately leading to increased mortality and reduced longevity in both humans and animals. The potential drawbacks of using mortality rates to infer animal welfare are also discussed, including its low sensitivity and the multiplicity of factors unrelated to affective states that can influence mortality rates. However, providing these issues are accounted for, it is suggested that this indicator has value in welfare assessment, and is especially well suited for cases where animals are allowed to live out their natural lifespans, such as tends to be the case with zoo and companion animals.

Qualitative Behavioural Assessment of emotionality in pigs

Scientific assessment of affective states in animals is challenging but vital for animal welfare studies. One possible approach is Qualitative Behavioural Assessment (QBA), a ‘whole animal’ methodology which integrates information from multiple behavioural signals and styles of behavioural expression (body language) directly in terms of an animal's emotional expression. If QBA provides a valid measure of animals’ emotional state it should distinguish between groups where emotional states have been manipulated. To test this hypothesis, QBA was applied to video-recordings of pigs, following treatment with either saline or the neuroleptic drug Azaperone, in either an open field or elevated plus-maze test. QBA analysis of these recordings was provided by 12 observers, blind to treatment, using a Free Choice Profiling (FCP) methodology. Generalised Procrustes Analysis was used to calculate a consensus profile, consisting of the main dimensions of expression. Dimension one was positively associated with terms such as ‘Confident’ and ‘Curious’ and negatively with ‘Unsure’ and ‘Nervous’. Dimension two ranged from ‘Agitated’/‘Angry’ to ‘Calm’/‘Relaxed’. In both tests, Azaperone pre-treatment was associated with a more positive emotionality (higher scores on dimension one reflecting a more confident/curious behavioural demeanour) than control pigs. No effect of drug treatment on dimension two was found. Relationships between qualitative descriptions of behaviour and quantitative behavioural measures, taken from the same recordings, were found. Overall, this work supports the use of QBA for the assessment of emotionality in animals.