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Buchner, H. H. F., Obermuller, S., & Scheidl, M. (2000). Body Centre of Mass Movement in the Sound Horse. The Veterinary Journal, 160(3), 225–234.
Abstract: The body centre of mass (BCM) is a key factor in the analysis of equine locomotion, as its position and movement determines the distribution and magnitude of loads on the limbs. In this study, the three-dimensional (3D) movement of the BCM in walking and trotting horses was assessed using a kinematic, segmental method. Thirty markers representing 20 body segments were recorded in 12 sound horses while standing, walking and trotting on a treadmill using a high-speed video system. Based on segmental inertial data, 3D positions of the segmental centres of mass as well as the total BCM were calculated. The position within the trunk during square standing and the movements of the BCM were determined for the three planes. The position of the BCM in the standing horse is presented relative to external reference points. At the trot, vertical displacement amplitude of the BCM amounted to 53 (6) mm as mean (sd), which was 27% smaller than external trunk movement. Medio-lateral displacement amplitude of the BCM was 19 (4) mm, 34% less than trunk amplitude. Sagittal forward-backward oscillations of the BCM independent from general forward movement were 13 (3) mm, being 24% less than trunk movements. At the walk, vertical, medio-lateral and sagittal BCM movements were smaller than trunk movements by 43, 65 and 65% respectively. The results show reduced and efficient BCM movements compared to the trunk and form a basis for the assessment of various clinical conditions such as lameness, the influence of a rider and various dressage performances.
Keywords: Horse; centre of mass; kinematics; segment model; locomotion.
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Massen, J., Sterck, E., & de Vos, H. (2010). Close social associations in animals and humans: functions and mechanisms of friendship (Vol. 147).
Abstract: Both humans and group-living animals associate and behave affiliatively more with some individuals than others. Human friendship has long been acknowledged, and recently scientists studying animal behaviour have started using the term friendship for close social associates in animals. Yet, while biologists describe friends as social tools to enhance fitness, social scientists describe human friendship as unconditional. We investigate whether these different descriptions reflect true differences in human friendship and animal close social associations or are a by-product of different research approaches: namely social scientists focussing on proximate and biologists on ultimate explanations. We first stress the importance of similar measures to determine close social associations, thereafter examine their ultimate benefits and proximate motivations, and discuss the latest findings on the central-neural regulation of social bonds. We conclude that both human friendship and animal close social associations are ultimately beneficial. On the proximate level, motivations for friendship in humans and for close social associations in animals are not necessarily based on benefits and are often unconditional. Moreover, humans share with many animals a similar physiological basis of sociality. Therefore, biologists and social scientist describe the same phenomenon, and the use of the term friendship for animals seems justified.
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Young, T., Creighton, E., Smith, T., & Hosie, C. (2012). A novel scale of behavioural indicators of stress for use with domestic horses. Applied Animal Behaviour Science, 140(1–2), 33–43.
Abstract: Behaviour scores (BS) offer non-invasive, objective and easy to use ways of assessing welfare in animals. Their development has, however, largely focused on behavioural reactions to stressful events (often induced), and little use of physiological measures has been made to underpin and validate the behavioural measures. This study aimed to develop a physiologically validated scale of behavioural indicators of stress for the purpose of welfare assessment in stabled domestic horses. To achieve this, behavioural and physiological data were collected from 32 horses that underwent routine husbandry procedures. Principal component analysis (PCA) of the behavioural and physiological data revealed three meaningful components that were used as the basis of the scale. Analysis of video clips of the horses’ responses to the husbandry procedures was undertaken by a panel of equestrian industry professionals using a free choice profiling (FCP) methodology. These results were added to the scale along with key definitions from relevant literature. Salivary cortisol levels were significantly correlated with the BS confirming the scale was meaningful and reflected physiological stress. The scale offers an easy to use ‘tool’ for rapid, reliable non-invasive welfare assessment in horses, and reduces the need for potentially invasive physiological measures.
Keywords: Horse; Behaviour scores; Cortisol; Saliva; Welfare assessment; Non-invasive
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Beckers, T., Miller, R. R., De Houwer, J., & Urushihara, K. (2006). Reasoning rats: forward blocking in Pavlovian animal conditioning is sensitive to constraints of causal inference. J Exp Psychol Gen, 135(1), 92–102.
Abstract: Forward blocking is one of the best-documented phenomena in Pavlovian animal conditioning. According to contemporary associative learning theories, forward blocking arises directly from the hardwired basic learning rules that govern the acquisition or expression of associations. Contrary to this view, here the authors demonstrate that blocking in rats is flexible and sensitive to constraints of causal inference, such as violation of additivity and ceiling considerations. This suggests that complex cognitive processes akin to causal inferential reasoning are involved in a well-established Pavlovian animal conditioning phenomenon commonly attributed to the operation of basic associative processes.
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Alexander, F., & Davies, M. E. (1969). Studies on vitamin B12 in the horse. Br. Vet. J., 125(4), 169–176.
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Ramos, D., Reche-Junior, A., Fragoso, P. L., Palme, R., Yanasse, N. K., Gouvêa, V. R., et al. (2013). Are cats (Felis catus) from multi-cat households more stressed? Evidence from assessment of fecal glucocorticoid metabolite analysis. Physiol. Behav., 122, 72–75.
Abstract: Abstract Given the social and territorial features described in feral cats, it is commonly assumed that life in multi-cat households is stressful for domestic cats and suggested that cats kept as single pets are likely to have better welfare. On the other hand, it has been hypothesized that under high densities cats can organize themselves socially thus preventing stress when spatial dispersion is unavailable. This study was aimed at comparing the general arousal underpinning emotional distress in single housed cats and in cats from multi-cat households (2 and 3–4 cats) on the basis of fecal glucocorticoid metabolites (GCM) measured via enzyme immunoassay (EIA). GCM did not significantly vary as a function of living style (single, double or group-housing); highly stressed individuals were equally likely in the three groups. Young cats in multi-cat households had lower GCM, and overall cats that tolerate (as opposed to dislike) petting by the owners tended to have higher GCM levels. Other environmental aspects within cat houses (e.g. relationship with humans, resource availability) may play a more important role in day to day feline arousal levels than the number of cats per se.
Keywords: Feline; Housing; Non-invasive; Enzyme immunoassay; Cortisol
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Gibson, B. M., & Shettleworth, S. J. (2005). Place versus response learning revisited: tests of blocking on the radial maze. Behav Neurosci, 119(2), 567–586.
Abstract: Neurobiological and behavioral research indicates that place learning and response learning occur simultaneously, in parallel. Such findings seem to conflict with theories of associative learning in which different cues compete for learning. The authors conducted place+response training on a radial maze and then tested place learning and response learning separately by reconfiguring the maze in various ways. Consistent with the effects of manipulating place and response systems in the brain (M. G. Packard & J. L. McGaugh, 1996), well-trained rats showed strong place learning and strong response learning. Three experiments using associative blocking paradigms indicated that prior response learning interferes with place learning. Blocking and related tests can be used to better understand how memory systems interact during learning.
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Lonon, A. M., & Zentall, T. R. (1999). Transfer of value from S+ to S- in simultaneous discriminations in humans. Am J Psychol, 112(1), 21–39.
Abstract: When animals learn a simultaneous discrimination, some of the value of the positive stimulus (S+) appears to transfer to the negative stimulus (S-). The present experiments demonstrate that such value transfer can also be found in humans. In Experiment 1 humans were trained on 2 simple simultaneous discriminations, the first between a highly positive stimulus, A (1,000 points); and a negative stimulus, B (0 points); and the second between a less positive stimulus, C (100 points); and a negative stimulus, D (0 points). On test trials, most participants preferred B over D. In Experiments 2 and 3 the value of the 2 original discriminations was equated in training (A[100]B[0] and C[100]D[0]). In Experiment 2 the values of the positive stimuli were then altered (A[1,000]C[0]); again, most participants preferred B over D. In Experiment 3, however, when the values of B and D were altered (B[1,000]D[0]), participants were indifferent to A and C. Thus, the mechanism that underlies value transfer in humans appears to be related to Pavlovian second-order conditioning. Similar mechanisms may be involved in assimilation processes in social contexts.
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Lloyd, A. S., Martin, J. E., Bornett-Gauci, H. L. I., & Wilkinson, R. G. (2008). Horse personality: Variation between breeds. Appl. Anim. Behav. Sci., 112(3-4), 369–383.
Abstract: Anecdotal evidence from horse owners and handlers suggests the existence of breed typical behaviour and personality in horses. This is further supported by current research on heritability of personality characteristics in a range of species. The Horse Personality Questionnaire (HPQ) is a 25-item rating method that has previously been shown to be reliable for the assessment of personality in horses. Principal component analysis on HPQ data has identified six underlying personality components in horses. These are Dominance, Anxiousness, Excitability, Protection, Sociability and Inquisitiveness. Using the HPQ a survey of 1223 horses of eight different breeds was completed. Data were analysed to explore any differences in personality between breeds across the six personality components. Breed differences in personality were identified, and it was noted that variability between breeds varied between personality components. Anxiousness and Excitability showed the most variation between breeds, whilst Dominance and Protection showed the least variance. The results identified breed typical personalities that were comparable to results from previous studies as well as anecdotal evidence provided by the popular equine literature. The results are discussed in terms of the potential selection pressures that may have resulted in these differences.
Keywords: Horse personality; Breed; Assessment; Questionnaire survey; Animal
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Gosling, S. D. (1998). Personality dimensions in spotted hyenas (Crocuta crocuta). J Comp Psychol, 112(2), 107–118.
Abstract: Personality ratings of 34 spotted hyenas (Crocuta crocuta) were made by 4 observers who knew the animals well. Analyses suggest that (a) hyena personality traits were rated with generally high reliability; (b) 5 broad dimensions (Assertiveness, Excitability, Human-Directed Agreeableness, Sociability, and Curiosity) captured about 75% of the total variance; (c) this dimensional structure could not be explained in terms of dominance status, sex, age, or appearance; and (d) as expected, female hyenas were more assertive than male hyenas. Comparisons with previous research provide evidence for the cross-species generality of Excitability, Sociability, and especially Assertiveness. Discussion focuses on methodological issues in research on animal personality and on the potential contributions this research can make for understanding the biological and environmental bases of personality.
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