Measures Of Affective State Research Articles

Variations in salivary oxytocin and eye caruncle temperature indicate response to environmental enrichment material in fattening pigs

Conventional pigs are typically raised under intensive conditions, which often do not meet pigs’ basic needs regarding behavioural expression and cognitive challenge, likely threatening their welfare. Thus, enabling the experience of positive affective states and, consequently, positive welfare should be encouraged. We investigated the potential of salivary oxytocin (sOXT) and eye (i.e., lachrymal caruncle region) temperature measured by infrared thermography as indicators of environmental enrichment material valuing in 32 conventional Yorkshire × Landrace pigs (110-day-old, mean ± SD body weight: 80.9±7.6 kg/pig) housed in 8 identical pens (3 female and 1 castrated male/pen; 3.3 m2/pig). Pigs were subjected to two contexts/days: fulfilment of expectation for fresh straw (i.e., delivery of 200 g of fresh straw/pig) and violation of expectation (i.e., no straw delivered). Additionally, based on footage of individual pigs from −30 min to +30 min relative to the moment when an experimenter left the pen after straw had been delivered or not (reference moment), we labelled behaviours more extensively investigated as measures of affective states (body posture; locomotor-rotational play, LOC; social play, SOC; aggression; tail motion; tail posture; tail tip lateralisation). Individual saliva samples were collected at −10 min and +20 min for analysis of sOXT and cortisol (sCORT), and individual thermograms were recorded at −10 min, −5 min and +10 min relative to the reference moment. Pigs tended to move their tail more often and tended to display more aggressions following straw provision. Furthermore, pigs displayed more playful events after the reference moment than before this event, irrespective of straw availability. However, pigs were mostly inactive (i.e., sitting or lying down) across contexts and no clear behavioural differences between contexts were detected. Similarly, we found no clear differences in sCORT concentrations between contexts. Alternatively, eye caruncle temperature and sOXT concentrations were higher on days when straw was provided. Our results suggest that salivary oxytocin and lachrymal caruncle temperature can be useful non-invasive tools to detect short-term responses to non-social stimuli in fattening pigs. Further research is needed and this study supports continuous development and validation of measures of affective state in domesticated animals.

Affective trajectories: Are hens influenced by positive and negative changes in their living conditions?

Most studies of the effects of housing and husbandry on animals' affective states and welfare investigate the impact of stable living conditions, comparing for example, animals living in enriched environments with those living in non-enriched ones. Changes in living conditions, including from more to less enriched environments, have also been found to have effects on measures of affective state and welfare in some species. But these studies have not investigated whether it is the trajectory of change that has affected the animals (e.g., worsening conditions), or simply the nature of their final environment (e.g., non-enriched). Here, we hypothesised that laying hens living in worsening conditions across a six-week period (gradually moving from preferred to non-preferred living conditions; "Trajectory to Non-Preferred", TNP, n = 30), would show evidence of more negative affective states and poorer welfare than those living continuously in non-preferred conditions for the same duration ("Stable Non-Preferred", SNP, n = 30). We also hypothesised that hens living in improving conditions (gradually moving from non-preferred to preferred living conditions; "Trajectory to Preferred", TP, n = 30), would show evidence of more positive affective states and better welfare than those living continuously in preferred conditions ("Stable Preferred", SP, n = 30). The preferred living condition provided extensive resources and intermittent rewarding events (such as the delivery of food treats) known to be valued and preferred by most hens, while the non-preferred living condition provided just basic resources and intermittent aversive events (e.g., loud noises). The hens' affective states and welfare were measured using home-pen behavioural observations, body condition assessments, physiological stress measures (e.g., blood corticosterone, glucose, etc.), physical challenge tests, and judgement bias tests. A number of differences between hens in the trajectory and stable living conditions were found: TP hens were lighter, showed more foraging behaviour and less standing alert and head-shaking than SP hens, while TNP hens showed more head-shaking, mild feather pecking and aggressive attacking of pen mates than SNP hens. However, some of these differences failed to reach significance following Benjamini adjustments for multiple testing. The groups also did not differ in their judgement biases (measured in a sub-sample of 12 hens per experimental group), response to physical challenges, or measures of physiological stress. We conclude that the hens in the present study showed some evidence of responsiveness to 'affective trajectories' in their living conditions, but no definitive effects on their affective states and welfare.

Repeatability of an attention bias test for sheep suggests variable influence of state and trait affect on behaviour.

Understanding the effects of repeated testing on behaviour is essential for behavioural tests that are re-applied to the same individuals for research and welfare assessment purposes. Assessing the repeatability of behaviour can also help us understand the influence of persistent traits vs transient states on animal responses during testing. This study examined the repeatability of behavioural responses in an attention bias test developed for sheep as a measure of affective state. Sheep were assessed in the attention bias test three times (n = 81 sheep), with testing occurring at intervals of 1 year then 2 weeks. During testing, individual sheep were exposed to a dog located behind a window for 3 s in a 4 × 4 m arena, then the dog was obscured from view, removed and sheep behaviours were recorded for 180 s. We hypothesised that behaviours in the test would have moderate-high repeatability but that the mean behavioural responses would change over consecutive trials as sheep habituated to the test environment. To estimate repeatability, data were modelled using restricted maximum likelihood linear mixed-effects models, fitting animal ID as a random effect. Vigilance behaviour, defined as having the head at or above shoulder height, was moderately repeatable (r = 0.58). Latency to eat (r = 0.20) and duration spent looking towards the previous location of the dog (attention to the dog wall) (r = 0.08) had low repeatability. Mean latency to eat did not differ significantly between trials (P = 0.2) and mean vigilance behaviour tended to decrease over the trials (P = 0.07). Mean duration of attention to the dog wall significantly decreased across the trials (P < 0.001), while mean zones crossed increased (P < 0.001), as did behaviours directed towards the exit door such as duration in proximity and pawing at the door. Overall, vigilance behaviour was moderately repeatable, suggesting it may have been driven by temperament or personality traits, while attention and feeding behaviours may have been more influenced by transient affective states or other factors, however further research is needed to better tease apart these potential effects. Sheep demonstrated some habituation to the test over consecutive trials. Care should therefore be taken during future application of the test to ensure all animals undergoing attention bias testing have equivalent experience for a valid interpretation of their relative behavioural responses.

Future application of an attention bias test to assess affective states in sheep

The affective states of animals comprise a key aspect of welfare that can be difficult to assess. An attention-bias test was developed for sheep, which assessed allocation of attention between a predator threat and a food reward, as a potential measure of affective state. The method was pharmacologically validated as a measure of anxiety-like states, finding that ‘anxious’ sheep were more vigilant, less likely to feed and spent more time looking towards the previous location of a dog than did ‘calm’ sheep. Across six further validation studies, the method was modified and explored as a measure of other types of affective states. This perspective article aims to provide guidance on what the method can tell us about affective state and make recommendations for further research by using this approach. Evidence was strongest across the studies for the test as a measure of anxiety-like states, but it is clear that there are other factors affecting animal behaviour during testing that need to be further investigated. One study showed potential for a modified method to assess depression-like states in sheep, while the impact of chronic stress on affect and attention bias remains unclear. It is likely that the test cannot be used to measure positive affect in sheep without further modification, due to the fear-eliciting nature of the test. Versions of the method using food as a positive stimulus allow for a clearer interpretation of attention than do versions using a conspecific photograph, and are recommended for use in future studies where appetite is not expected to be a confounding factor. In this context, vigilance behaviour may indicate trait anxiety or fearfulness, while other measures of attention may be more sensitive to transient changes in affect. Modifications to the method are suggested to allow for a clearer characterisation of attention in livestock species and to improve the practical application of the test. Overall, the attention-bias test shows promise as a measure of negative affective states, but the method is still very new and further research is needed to better determine its potential use as a welfare-assessment tool.

How emotions induced by reading influence sleep quality in young and older adults

Objectives This study examined whether emotions induced by reading before sleep influence sleep quality in young and older adults. Method Sixty older adults (64–75 years) and 60 young adults (18–35 years) were randomly assigned to three conditions: positive reading, neutral reading, and control. The reading groups read a short story at bedtime, whereas the control group kept its routine. Participants completed measures of affective states, subjective sleep parameters, and self-reported sleep quality related to emotions over 7 consecutive days. Results Older adults reported much longer sleep latency and lower sleep efficiency than young adults. In both reading conditions, older adults reported reduced sleep latencies compared to the control group. In the positive reading condition, older adults reported an increased sleep duration compared to younger adults and the other conditions. Young and older adults in the positive condition showed better self-reported sleep quality than those in the neutral conditions, regardless of age. Conclusions Reading at bedtime appears to reduce older adults’ time to fall asleep and increase their sleep duration. Positive emotions induced by reading short stories at bedtime seem to be a sleep-promoting factor that improves bedtime and wake time in young and older adults.

The effect of repeated testing on judgement bias in domestic dogs (Canis familiaris)

Judgement bias paradigms are increasingly being used as a measure of affective state in dogs. Approach to an ambiguous stimulus is commonly used as a measure of affect, however, this may also be influenced by learning. This study directly measured the impact of learning on a commonly used judgement bias paradigm in the absence of an affective state manipulation. Dogs (N = 15) were tested on a judgement bias task across five sessions. The dogs’ latency to approach a bowl placed in one of three ambiguous locations between non-baited (negative) and baited (positive) locations was measured. Results show that session number had a significant effect on the dogs’ latencies to reach the ambiguous bowl locations, with post-hoc tests revealing that dogs were significantly slower to approach the locations as the number of sessions increased. Session number also had a significant effect on the number of times the dogs did not approach the bowl within 30 s of being released, with the number of no approaches generally increasing across sessions. When dog identity was included as a fixed effect, a significant effect on latency to approach was found, suggesting that some dogs were consistently faster than others across sessions. To assess whether the paradigm produced repeatable results, Intraclass Correlation Coefficients were used. A low degree of reliability was found between latencies to approach each bowl position across sessions. This study demonstrates that dogs learned that the ambiguous locations were not rewarded with repeated exposures, and that this impacted their responses. We conclude that this judgement bias paradigm may require further consideration if applied across multiple exposures and that repeated results should be interpreted with caution as they are likely impacted by learning.

A pilot study examining the suitability of the mental arithmetic task and single-item measures of affective states to assess affective, physiological, and attention restoration at a wooden desk

People seem to function and feel better in indoor natural environments, including spaces furnished with wood. When restorative effects of indoor spaces are not detected, suboptimal methodological approaches may be responsible, including stress-inducing activities and measures of affective states and cognitive performance. Our primary objectives were to test (1) whether the Mental Arithmetic Task (MAT) can reliably induce stress and measure cognitive performance, and (2) whether two single-item measures of pleasure and arousal can detect changes in affective states in restoration research. Our secondary objective was to examine whether stress recovery and cognitive performance differ between indoor settings furnished with or without wood. Twenty-two participants, allocated to a space furnished with either a wooden or a white desktop, completed MAT twice, while their electrodermal and cardiovascular activity and affective states were monitored. Participants on average responded to MAT with increased subjective arousal but unchanged subjective pleasure, and with increased physiological arousal on some but not all parameters, suggesting that MAT was effortful but not necessarily stressful. Scores on MAT improved at the 2nd administration, suggesting that MAT did not induce cognitive fatigue at the 1st administration and that its role as a cognitive task in restoration research may be limited. The items assessing affective states performed well. The measured outcomes did not differ between the wooden and non-wooden setting, suggesting that substantial restorative effects of a wooden desktop are unlikely, and that higher wood coverage is needed to increase the chances of observing restorative effects.

Judgment Bias During Gestation in Domestic Pigs.

In humans and rats, changes in affect are known to occur during pregnancy, however it is unknown how gestation may influence mood in other non-human mammals. This study assessed changes in pigs' judgment bias as a measure of affective state throughout gestation. Pigs were trained to complete a spatial judgment bias task with reference to positive and negative locations. We tested gilts before mating, and during early and late gestation, by assessing their responses to ambiguous probe locations. Pigs responded increasingly negatively to ambiguous probes as gestation progressed and there were consistent inter-individual differences in baseline optimism. This suggests that the pigs' affective state may be altered during gestation, although as a non-pregnant control group was not tested, an effect of learning cannot be ruled out. These results suggest that judgment bias is altered during gestation in domestic pigs, consequently raising novel welfare considerations for captive multiparous species.

Assessing animal welfare: a triangulation of preference, judgement bias and other candidate welfare indicators

To assess the welfare of captive animals, validated measures, so-called ‘welfare indicators’, are required. We used a triangulation approach to investigate the extent to which different measures converged to provide corroborating evidence of welfare. Laying hens were exposed to living conditions designed to be generally preferred (GP) or generally nonpreferred (GNP), using previous studies of chickens’ majority preferences for resources and environments. The hens were also tested at the end of the study to identify their individual preferences for these living conditions, assigned to groups that showed an individual preference, or nonpreference, for their own experimental housing, regardless of whether it was generally preferred or not (IP and INP). Both GP and IP birds showed more ground-foraging behaviour, and lower pulse rates during handling, than GNP and INP birds. Individual preference was associated with more optimistic-like judgement biases when birds were tested after 6 weeks of exposure to these living conditions, but not after 24 weeks. Serum blood glucose levels were also lower in hens showing individual preferences for their experimental living conditions. General preferences were associated with a number of measures, including higher rates of ground-foraging behaviour and lower faecal water content (after both 6 and 24 weeks), lower pulse rate during handling and greater tibia strength and stiffness post mortem. There were no associations between judgement bias and other candidate welfare indicators, but it is not clear whether this represents evidence of absence or merely absence of evidence. Overall, the different approaches did not converge to identify a precise state of animal welfare, although some measures (preference, stress indicators: pulse rate, faecal water and blood glucose, foraging behaviour) were aligned consistently across timescales. We conclude that further work is needed to establish which alternative measures of affective state might be more appropriate indicators of animal welfare.

No Evidence for a Role of Oral Contraceptive-Use in Emotion Recognition But Higher Negativity Bias in Early Follicular Women.

Accuracy in facial emotion recognition has shown to vary with ovarian hormones, both in naturally cycling women, as well as in women taking oral contraceptives. It remains uncertain however, if specific – endogenous and exogenous – hormonal levels selectively impact recognition of certain basic emotions (or neutral faces) and if this relationship coincides with certain affective states. Therefore, we investigated 86 women under different hormonal conditions and compared their performance in an emotion recognition task as well as self-reported measures of affective states. Based on self-reported cycle days and ovulation testing, the participants have been split into groups of naturally cycling women during their early follicular phase (fNC, n = 30), naturally cycling women during their peri-ovulatory phase (oNC, n = 26), and women taking oral contraceptives (OC, n = 30). Participants were matched for age and did not differ in education or neuropsychological abilities. Self-reported anxiety and depressive affective state scores were similar across groups, but current affective state turned out to be significantly more negative in fNC women. Independent of negative affective state, fNC women showed a significantly higher negativity bias in recognizing neutral faces, resulting in a lower recognition accuracy of neutral faces compared to oNC and OC women. In the OC group only, negative affective state was associated with lower recognition accuracy and longer response times for neutral faces. Furthermore, there was a significant, positive association between disgust recognition accuracy and negative affective state in the fNC group. Low progesterone levels during the early follicular phase were linked to higher negative affective state, whereas in the peri-ovulatory phase they were linked to elevated positive affective state. Overall, previous findings regarding impaired emotion recognition during OC-use were not confirmed. Synthetic hormones did not show a correlation with emotion recognition performance and affective state. Considering the important role of emotion recognition in social communication, the elevated negativity bias in neutral face recognition found for fNC women may adversely impact social interactions in this hormonal phase.

Personal values in mental disorders: an exploratory analysis

Personal values have increasingly become central in socio-psychological research. However, the relationships between values and psychopathological variables have been scarcely investigated, with mixed results. This study aimed to explore potential differences in value orientation in a sample of people with psychotic disorders and mood disorders compared to a non-clinical sample using the Schwarz’s values framework. A clinical sample of 162 subjects (92 subjects with psychotic disorders and 70 with mood disorders) and a non-clinical sample of 217 subjects completed the self-report measures of affective states (PANAS) and personal values (PVQ). Irrespective of the diagnostic group, the clinical sample showed higher expression of Conservation values (i.e., Tradition, Conformity, Security). Conservation and Self-enhancement values positively correlated with PANAS-positive affectivity in the clinical sample; in the non-clinical sample, Self-enhancement values only correlated with PANAS-positive affectivity. The expression of Conservation values in individuals with a mental disorder could reflect an orientation toward Conformity underlying fundamental affiliative goals. The complex relationship between personal values and clinical constructs should be further investigated, with important theoretical and clinical implications in mental health.

A Spanish adaptation of the implicit positive and negative affect test (IPANAT).

Self-report measures of affective states (i.e., explicit measure) underlie a variety of cognitive biasing factors. Therefore, measures for the indirect assessment of affect (i.e., implicit) have previously been developed, such as the Implicit Positive and Negative Affect Test. The IPANAT asks participants to make judgments about the degree to which artificial non-sense words sound like affective states, and has demonstrated good reliability and validity. We created a Spanish version of this test (IPANAT-SPAIN). After adapting artificial words to Spanish language, based on preliminary studies, the IPANAT-SPAIN was administered to a representative sample of N = 468 adults from Spain (225 men). Competing models of its latent structure were evaluated using confirmatory factor analysis. To assess convergent validity, we correlated the IPANAT-SPAIN with explicit measures of affect. The best-fitting model consisted of two factors corresponding to positive implicit affect (PA) and negative implicit affect (NA). Reliability of the IPANAT-SPAIN was a = .94 for PA, and a = .88 for NA. The pattern of relationships between the IPANAT-SPAIN and explicit affect measures were consistent with previous findings. The results indicate that the Spanish adaptation of the IPANAT has satisfactory psychometric properties.

High-intensity interval training for patients with coronary artery disease: Finding the optimal balance

BackgroundThe optimal characteristics of high-intensity interval training (HIIT) for patients with coronary artery disease (CAD) within cardiac rehabilitation (CR) are unclear. We assessed a HIIT protocol designed to balance patient safety, efficacy and enjoyment. MethodsTwenty-nine patients with CAD completed 6-weeks (× 2 sessions per week) of HIIT within outpatient (phase 2) CR. HIIT comprised 15 repetitions × 30-seconds cycling at ∼85-90% maximum heart rate, interspersed with 30-seconds of active recovery. Key outcomes covered patient safety, efficacy (peak aerobic capacity, body composition, blood pressure and vascular function), and patient adherence and enjoyment. ResultsNo cardiovascular-related adverse events were reported in relation to HIIT sessions. Patients showed significant improvement in peak aerobic capacity (mean +12%, p < 0.001, effect size d = 0.38), blood pressure (brachial systolic -7mmHg, p < 0.001, d = -0.59) and total body fat (-4%, p < 0.001, d = -0.49). Central adaptations were prominent (aortic systolic BP -5mmHg, p = 0.001, d = -0.50; visceral fat -10%, p = 0.001, d = -0.41). Patient enjoyment of training was high (5.5 out of 7 using the Exercise Enjoyment Scale) and measures of affective state improved following training (assorted p < 0.018). ConclusionsThis HIIT protocol appears safe, effective and enjoyable for patients with CAD within CR. Improved aerobic fitness, blood pressure and body fat levels were observed indicating improved cardiovascular-risk. High patient enjoyment and improved mood suggest the HIIT could be sustainable for patients in the longer-term.

Emotional processes in human-robot interaction during brief cognitive testing

With the rapid rise in robot presence in a variety of life domains, understanding how robots influence people's emotions during human-robot interactions is important for ensuring their acceptance in society. Mental health care, in particular, is considered the field in which robotics technology will bring the most dramatic changes in the near future. In this context, the present study sought to determine whether a brief cognitive assessment conducted by a robot elicited different interaction-related emotional processes than a traditional assessment conducted by an expert clinician. A non-clinical sample of 29 young adults (17 females; M = 24.5, SD = 2.3 years) were asked to complete two cognitive tasks twice, in counterbalanced order, once administered by an expert clinician and once by an autonomous humanoid robot. Self-reported measures of affective states and assessment of physiological arousal did not reveal any difference in emotional processes between human-human and human-robot interactions. Similarly, cognitive performances and workload did not differ across conditions. Analysis of non-verbal behaviour, however, showed that participants spent more time looking at the robot (d = 1.3) and made fewer gaze aversions (d = 1.3) in interacting with the robot than with the human examiner. We argue that, far from being a trivial ‘cosmetic change’, using a social robot in place of traditional testing could be a potential way to open up the development of a new generation of tests for brief cognitive assessment.

A Judgement Bias Test to Assess Affective State and Potential Therapeutics in a Rat Model of Chemotherapy-Induced Mucositis

Chemotherapy-induced mucositis is an extremely painful condition that occurs in 40–60% of patients undergoing chemotherapy. As mucositis currently has no effective treatment, and due to the self-limiting nature of the condition, the major treatment aims are to manage symptoms and limit pain with significance placed on improving patient quality of life. Rodent models are frequently used in mucositis research. These investigations typically assess pathological outcomes, yet fail to include a measure of affective state; the key therapeutic goal. Assessment of cognitive biases is a novel approach to determining the affective state of animals. Consequently, this study aimed to validate a cognitive bias test through a judgement bias paradigm to measure affective state in a rat model of chemotherapy-induced intestinal mucositis. Rats with intestinal mucositis demonstrated a negative affective state, which was partially ameliorated by analgesic administration, whilst healthy rats showed an optimistic response. This study concluded that the judgement bias test was able to evaluate the emotional state of rats with chemotherapy-induced mucositis. These findings provide a foundation for future refinement to the experimental design associated with the animal model that will expedite successful transitioning of novel therapeutics to clinical practice, and also improve humane endpoint implementation.

I say thee “neigh”: Rescued equids are optimistic in a judgment bias test

Abstract Changes in the affective state of neglected or abused animals can be difficult to quantify relative to physical improvements following rescue. Judgment bias as a measure of affective state was assessed in 8 horses and 2 donkeys that differed in their care history (abused/neglected or nonabused/non-neglected, hereafter described as rescued/nonrescued). On each training trial, a single bucket was presented at 1 of 2 locations; one that always contained food (reward) and another that never contained food (nonreward), and the latency to approach within 1 m of the bucket was recorded. Once differential responding to the 2 locations was established, buckets were presented at ambiguous locations (spatially intermediate between the reward and nonreward locations). Both groups approached the middle location with intermediate latencies. However, care history moderated the difference in latencies to respond to the reward versus the ambiguous locations. In fact, rescued equids approached the ambiguous locations more quickly than the nonrescued equids did, although there was no difference in approach to the reward stimulus. These results suggest that prior poor treatment at the hands of humans does not induce lasting pessimistic judgment biases, but further work is needed to examine changes in judgment bias following neglect or abuse.

The Influence of Keel Bone Damage on Welfare of Laying Hens.

This article reviews current knowledge about welfare implications of keel bone damage in laying hens. As an initial part, we shortly describe the different conditions and present major risk factors as well as findings on the prevalence of the conditions. Keel bone damage is found in all types of commercial production, however with varying prevalence across systems, countries, and age of the hens. In general, the understanding of animal welfare is influenced by value-based ideas about what is important or desirable for animals to have a good life. This review covers different types of welfare indicators, including measures of affective states, basic health, and functioning as well as natural living of the birds, thereby including the typical public welfare concerns. Laying hens with keel bone fractures show marked behavioral differences in highly motivated behavior, such as perching, nest use, and locomotion, indicating reduced mobility and potentially negative affective states. It remains unclear whether keel bone fractures affect hen mortality, but there seem to be relations between the fractures and other clinical indicators of reduced welfare. Evidence of several types showing pain involvement in fractured keel bones has been published, strongly suggesting that fractures are a source of pain, at least for weeks after the occurrence. In addition, negative effects of fractures have been found in egg production. Irrespective of the underlying welfare concern, available scientific evidence showed that keel bone fractures reduce the welfare of layers in modern production systems. Due to the limited research into the welfare implications of keel bone deviation, evidence of the consequences of this condition is not as comprehensive and clear. However, indications have been found that keel bone deviations have a negative impact on the welfare of laying hens. In order to reduce the occurrence of the conditions as well as to examine how the affected birds should be treated, more research into the welfare implications of keel bone damage is needed. Research should focus on effects of genetic lines, genetic selection, housing, and nutrition for the development, prevalence, and severity of these conditions, preferably conducted as longitudinal and/or transnational studies.

Cognitive judgement bias is associated with frequency of anticipatory behavior in bottlenose dolphins.

Many animals display a suite of increased vigilance and/or activity responses in relation to upcoming events, termed "anticipatory behavior." Anticipatory behavior toward positive events has been suggested as a cross-species measure of affective state as it likely reflects the balance of the reward-sensitivity system: various studies suggest that animals in poorer welfare situations show higher or excessive levels of anticipation for positive events. Another tool for evaluating animals' affective state is cognitive bias testing, and although it has been attempted, a link has not yet been made between cognitive bias and anticipatory behavior levels. Bottlenose dolphins (Tursiops truncatus) in captivity increase the performance of behaviors such as surface-looking and spy-hopping in anticipation of training sessions during which food is provided. In this study we measured anticipatory behavior frequency in bottlenose dolphins prior to positive reinforcement training sessions, and assessed whether frequency of anticipatory behavior correlated with their performance on cognitive bias tasks. We found that higher frequencies of anticipatory behavior for training sessions was significantly associated with more pessimistic judgements in cognitive bias tests, supporting previous findings linking higher reward sensitivity with negative affective states. Anticipatory behavior is an easily measured activity and could represent a welfare indicator in dolphins as well as other animals in captive environments.

Effects of commercially produced almond by-products on chemotherapy-induced mucositis in rats.

AIMTo determine if almond extracts reduce the severity of chemotherapy-induced mucositis as determined through biochemical, histological and behavioural markers.METHODSIntestinal mucositis is a debilitating condition characterized by inflammation and ulceration of the gastrointestinal mucosa experienced by cancer patients undergoing chemotherapy. Certain bioactive plant products have shown promise in accelerating mucosal repair and alleviating clinical symptoms. This study evaluated almond extracts for their potential to reduce the severity of chemotherapy-induced mucositis in Dark Agouti rats. Female Dark Agouti rats were gavaged (days 3-11) with either PBS, almond hull or almond blanched water extract at two doses, and were injected intraperitoneally with 5-fluorouracil (5-FU-150 mg/kg) or saline on day 9 to induce mucositis. Burrowing behavior, histological parameters and myeloperoxidase activity were assessed.RESULTSBodyweight was significantly reduced in rats that received 5-FU compared to saline-treated controls (P < 0.05). Rats administered 5-FU significantly increased jejunal and ileal MPO levels (1048%; P < 0.001 and 409%; P < 0.001), compared to healthy controls. Almond hull extract caused a pro-inflammatory response in rats with mucositis as evidenced by increased myeloperoxidase activity in the jejunum when compared to 5-FU alone (rise 50%, 1088 ± 96 U/g vs 723 ± 135 U/g, P = 0.02). Other extract-related effects on inflammatory activity were minimal. 5-FU significantly increased histological severity score compared to healthy controls confirming the presence of mucositis (median of 9.75 vs 0; P < 0.001). The extracts had no ameliorating effect on histological severity score in the jejunum or ileum. Burrowing behavior was significantly reduced in all chemotherapy-treated groups (P = 0.001). The extracts failed to normalize burrowing activity to baseline levels.CONCLUSIONAlmond extracts at these dosages offer little beneficial effect on mucositis severity. Burrowing provides a novel measure of affective state in studies of chemotherapy-induced mucositis.

Can the way pigs are handled alter behavioural and physiological measures of affective state?

Research on human-animal relationship in animal production has been mainly focused on its effect on stress, productivity and meat quality. Only few studies have assessed its effects on the animals’ affective state. In the present study, the influence of positive and negative handling (pH and NH, respectively) on affective state and fear as assessed by the cognitive bias test, the novel object test and the defence cascade test was studied in 56 pigs. Serum, saliva and hair were sampled during the study for the analysis of cortisol concentration. Results showed no differences between pH and NH pigs in the behavioural tests, which may be either due to the lack of previous handling effect on the test results, the lack of validity or the low sensitivity of these tests or a combination of them. Moreover, no differences were found in cortisol concentrations between handling groups. However, correlations between tests were found (p<0.05) suggesting that there are individual factors such as the fear level, the motivation or the coping style, that have a similar effect on the response to these tests. Moreover, pigs who were more fearful had higher (r=0.37; p=0.014) levels of serum cortisol at slaughter.