Modulation of short-term emotions by long-term mood is little understood but relevant to understand the affective system and of importance in respect to animal welfare: a negative mood might taint experiences, whilst a positive mood might alleviate single negative events. To induce different mood states in sheep housing conditions were varied. Fourteen ewes were group-housed in an unpredictable, stimulus-poor and 15 ewes in a predictable, stimulus-rich environment. Sheep were tested individually for mood in a behavioural cognitive bias paradigm. Also, their reactions to three physical stimuli thought to differ in their perceived valence were observed (negative: pricking, intermediate: slight pressure, positive: kneading). General behaviour, activity, ear movements and positions, and haemodynamic changes in the cortical brain were recorded during stimulations. Generalised mixed-effects models and model probabilities based on the BIC (Bayesian information criterion) were used. Only weak evidence for mood difference was found. Sheep from the unpredictable, stimulus-poor housing condition had a somewhat more negative cognitive bias, showed slightly more aversive behaviour, were slightly more active and moved their ears somewhat more. Sheep most clearly differentiated the negative from the intermediate and positive stimulus in that they exhibited more aversive behaviour, less nibbling, were more active, showed more ear movements, more forward ear postures, fewer backward ear postures, and a stronger decrease in deoxyhaemoglobin when subjected to the negative stimulus. In conclusion, sheep reacted towards stimuli according to their presumed valence but their mood was not strongly influenced by housing conditions. Therefore, behavioural reactions and cortical brain activity towards the stimuli were hardly modulated by housing conditions. Modulation of short-term emotions by long-term mood is little understood but relevant to 34 understand the affective system and of importance in respect to animal welfare: a negative 35 mood might taint experiences, whilst a positive mood might alleviate single negative events. 36To induce different mood states in sheep housing conditions were varied. Fourteen ewes 37 were group-housed in an unpredictable, stimulus-poor and 15 ewes in a predictable, 38 stimulus-rich environment. Sheep were tested individually for mood in a behavioural 39 cognitive bias paradigm. Also, their reactions to three physical stimuli thought to differ in their 40 Only weak evidence for mood difference was found. Sheep from the unpredictable, stimulus-45 poor housing condition had a somewhat more negative cognitive bias, showed slightly more 46 aversive behaviour, were slightly more active and moved their ears somewhat more. Sheep 47 most clearly differentiated the negative from the intermediate and positive stimulus in that 48 they exhibited more aversive behaviour, less nibbling, were more active, showed more ear 49 movements, more forward ear postures, fewer backward ear postures, and a stronger 50...

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Mood, as a long-term affective state, is thought to modulate short-term emotional reactions in animals, but the details of this interplay have hardly been investigated experimentally. Apart from a basic interest in this affective system, mood is likely to have an important impact on animal welfare, as bad mood may taint all emotional experience. In the present study about mood -emotion interaction, 29 sheep were kept under predictable, stimulus-rich or unpredictable, stimulus-poor housing conditions, to induce different mood states. In an experiment, the animals were confronted with video sequences of social interactions of conspecifics showing agonistic interactions, ruminating or tolerantly co-feeding as stimuli of different valences. Emotional reactions were assessed by measuring frontal brain activity using functional near-infrared spectroscopy and by recording behavioral reactions. Attentiveness of the sheep decreased from videos showing agonistic interactions toruminating sheep to those displaying co-feeding sheep. Seeing agonistic interactions was also associated with a deactivation of the frontal cortex, specifically in animals living under predictable, stimulus-rich housing conditions. These sheep generally showed less attentiveness and locomotor activity and they had their ears in a forward position less often and in a backward position more often than the sheep from the unpredictable, stimulus-poor conditions. Housing conditions influenced how the sheep behaved, which can either be thought to be mediated by mood or by the animals' previous experience with stimulusrichness in their housing conditions. Frontal cortical activity may not depend on valence only, but also on the perceptual channel through which the stimuli were perceived.

Given the increased interest in animal emotional reactions for assessing welfare, indicators for such reactions are sought. Ear postures and movements have been found to be promising indicators of emotional states in sheep and other animals. The manual recording of ear postures, however, is very time consuming and possibly prone to a degree of inaccuracy due to the subtle and fast nature of ear movements that have to be identified. Therefore, a number of previous studies have analysed the frequency of certain ear postures relative to all ear posture changes rather than measuring the relative duration spent with different ear postures. Here, we present an automated, continuous tracking system that keeps track of small and lightweight marker balls attached to the head and ears of sheep. We measured ear postures and movements when the animals were confronted with three physical stimuli thought to differ in valence (from negative to intermediate to positive). We then compared new ear-posture definitions reflecting the real time spent with certain ear postures during stimulation with previous definitions used for video-based analyses that assessed ear-posture changes in relation to the total number of observed ear postures. In the analysis, we correlated new and previous measures both between and within experimental stimuli using residuals from mixed-effects models. We found that the new and previous definitions of ear postures and movements correlated highly. Given these high correlations and the discussed theoretical and practical advantages of the automated tracking, the new recording system can be recommended highly for assessing reactions in animals that may indicate emotional states.

Many stimuli evoke short-term emotional reactions. These reactions may play an important role in assessing how a subject perceives a stimulus. Additionally, long-term mood may modulate the emotional reactions but it is still unclear in what way. The question seems to be important in terms of animal welfare, as a negative mood may taint emotional reactions. In the present study with sheep, we investigated the effects of thermal stimuli on emotional reactions and the potential modulating effect of mood induced by manipulations of the housing conditions. We assume that unpredictable, stimulus-poor conditions lead to a negative and predictable, stimulus-rich conditions to a positive mood state. The thermal stimuli were applied to the upper breast during warm ambient temperatures: hot (as presumably negative), intermediate, and cold (as presumably positive). We recorded cortical activity by functional near-infrared spectroscopy, restlessness behavior (e.g., locomotor activity, aversive behaviors), and ear postures as indicators of emotional reactions. The strongest hemodynamic reaction was found during a stimulus of intermediate valence independent of the animal’s housing conditions, whereas locomotor activity, ear movements, and aversive behaviors were seen most in sheep from the unpredictable, stimulus-poor housing conditions, independent of stimulus valence. We conclude that, sheep perceived the thermal stimuli and differentiated between some of them. An adequate interpretation of the neuronal activity pattern remains difficult, though. The effects of housing conditions were small indicating that the induction of mood was only modestly efficacious. Therefore, a modulating effect of mood on the emotional reaction was not found.

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