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Zhang, T. - Y., Parent, C., Weaver, I., & Meaney, M. J. (2004). Maternal programming of individual differences in defensive responses in the rat. Ann N Y Acad Sci, 1032, 85–103.
Abstract: This paper describes the results of a series of studies showing that variations in mother-pup interactions program the development of individual differences in behavioral and endocrine stress responses in the rat. These effects are associated with altered expression of genes in brain regions, such as the amygdala, hippocampus, and hypothalamus, that regulate the expression of stress responses. Studies from evolutionary biology suggest that such “maternal effects” are common and often associated with variations in the quality of the maternal environment. Together these findings suggest an epigenetic process whereby the experience of the mother alters the nature of the parent-offspring interactions and thus the phenotype of the offspring.
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Gould, J. L. (2004). Animal cognition. Curr Biol, 14(10), R372–5.
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Brennan, P. A. (2004). The nose knows who's who: chemosensory individuality and mate recognition in mice. Horm Behav, 46(3), 231–240.
Abstract: Individual recognition is an important component of behaviors, such as mate choice and maternal bonding that are vital for reproductive success. This article highlights recent developments in our understanding of the chemosensory cues and the neural pathways involved in individuality discrimination in rodents. There appear to be several types of chemosensory signal of individuality that are influenced by the highly polymorphic families of major histocompatibility complex (MHC) proteins or major urinary proteins (MUPs). Both have the capability of binding small molecules and may influence the individual profile of these chemosignals in biological fluids such as urine, skin secretions, or saliva. Moreover, these proteins, or peptides associated with them, can be taken up into the vomeronasal organ (VNO) where they can potentially interact directly with the vomeronasal receptors. This is particularly interesting given the expression of major histocompatibility complex Ib proteins by the V2R class of vomeronasal receptor and the highly selective responses of accessory olfactory bulb (AOB) mitral cells to strain identity. These findings are consistent with the role of the vomeronasal system in mediating individual discrimination that allows mate recognition in the context of the pregnancy block effect. This is hypothesized to involve a selective increase in the inhibitory control of mitral cells in the accessory olfactory bulb at the first level of processing of the vomeronasal stimulus.
Keywords: Animals; Chemoreceptors/physiology; Discrimination Learning/*physiology; Embryo Implantation/physiology; Female; Individuality; Major Histocompatibility Complex/physiology; Male; Mice; Neurons, Afferent/physiology; Nose/cytology/physiology; Perception/physiology; Pregnancy; Pregnancy Maintenance/physiology; Pregnancy, Animal/*physiology; Receptors, Odorant/*physiology; Recognition (Psychology)/*physiology; Sexual Behavior, Animal/*physiology; Smell/*physiology; Urine/physiology; Vomeronasal Organ/cytology/physiology
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Overli, O., Korzan, W. J., Hoglund, E., Winberg, S., Bollig, H., Watt, M., et al. (2004). Stress coping style predicts aggression and social dominance in rainbow trout. Horm Behav, 45(4), 235–241.
Abstract: Social stress is frequently used as a model for studying the neuroendocrine mechanisms underlying stress-induced behavioral inhibition, depression, and fear conditioning. It has previously been shown that social subordination may result in increased glucocorticoid release and changes in brain signaling systems. However, it is still an open question which neuroendocrine and behavioral differences are causes, and which are consequences of social status. Using juvenile rainbow trout of similar size and with no apparent differences in social history, we demonstrate that the ability to win fights for social dominance can be predicted from the duration of a behavioral response to stress, in this case appetite inhibition after transfer to a new environment. Moreover, stress responsiveness in terms of confinement-induced changes in plasma cortisol was negatively correlated to aggressive behavior. Fish that exhibited lower cortisol responses to a standardized confinement test were markedly more aggressive when being placed in a dominant social position later in the study. These findings support the view that distinct behavioral-physiological stress coping styles are present in teleost fish, and these coping characteristics influence both social rank and levels of aggression.
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Laland K.N. (2004). Social learning strategies. Learn. Behav., 32, 4–14.
Abstract: In most studies of social learning in animals, no attempt has been made to examine the nature of the strategy adopted by animals when they copy others. Researchers have expended considerable effort in exploring the psychological processes that underlie social learning and amassed extensive data banks recording purported social learning in the field, but the contexts under which animals copy others remain unexplored. Yet, theoretical models used to investigate the adaptive advantages of social learning lead to the conclusion that social learning cannot be indiscriminate and that individuals should adopt strategies that dictate the circumstances under which they copy others and from whom they learn. In this article, I discuss a number of possible strategies that are predicted by theoretical analyses, including copy when uncertain, copy the majority, and copy if better, and consider the empirical evidence in support of each, drawing from both the animal and human social learning literature. Reliance on social learning strategies may be organized hierarchically, their being employed by animals when unlearned and asocially learned strategies prove ineffective but before animals take recourse in innovation.
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Baldi, R., Pelliza-Sbriller, A., Elston, D., & Albon, S. (2004). High Potential For Competition Between Guanacos And Sheep In Patagonia. Journal of Wildlife Management, 68(4), 924–938.
Abstract: Guanacos (Lama guanicoe) are the largest native Artiodactyl in South America and the most widely distributed. In arid Patagonia, densities are low and negatively related to domestic sheep numbers in space and time consistent with interspecific competition theory. Although guanacos and domestic sheep have been described as intermediate feeders sharing food resources, no studies have been conducted to compare their diets in sympatric conditions and explore whether the potential exists for direct interspecific competition. We assessed the diet of both species across 9 different sites and 2 seasons by microhistological analysis of fecal samples. We found that (1) guanacos and sheep are generalist herbivores feeding on a wide range of plant species; (2) both are intermediate feeders able to include both monocotyledoneous and dicotyledoneous plants in their diet; (3) both are able to change their diets seasonally; and (4) food niche overlap is high, particularly in summer when food resources are more scarce than in spring. We conclude that the potential for competition between guanacos and sheep is high and could have played a major role in the demise of guanacos. Consequently, current management practices focused on maximizing sheep numbers are not compatible with the recovery of guanaco populations.
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Broucek, J., Uhrincat, M., KiÅ¡ac, P., Hanus, A.. (2004). Hair Whorl Position as a Predictor of Learning Ability and Locomotor Behavior in Cattle? ACTA VET. BRNO, 73(4), 455–459.
Abstract: The aim of our work was to investigate the hypothesis that the speed of solving the maze tests and
locomotor behavior of heifers in open-field tests are affected by the height location of facial whorl. Fifty-eight Holstein heifers were used. Maze learning was observed at the age of 15 weeks, and an open-field test was applied at two ages, 16 weeks and 18 months. Whorl placement was recorded by one person as each heifer entered the scale. The hair whorl position was determined on the basis of two patterns: A) hair whorl high, middle and low and B) hair whorl high and low. Heifers with a high hair whorl were the fastest (77.8 ± 84.3 s) and heifers with a middle hair whorl the slowest (87.3 ± 100.3 s) in the A pattern during the maze tests. In the B whorl pattern, heifers with a high hair whorl ran across the maze in 84.5 ± 95.2 s and heifers with a low hair whorl in 84.1 ± 97.9 s. The number of crossed squares in a 5-minute open-field test in the A pattern was the non-significantly highest in heifers with a high hair whorl (43.4) at the age of 16 weeks. In the B whorl pattern, heifers with a high hair whorl were also more mobile, but neither differences in individual minutes nor in the whole 5 minutes were significant. Heifers with a high hair whorl displayed the strongest locomotory behavior (37.6 squares) and heifers with a low hair whorl (30.8) were the slowest in the A pattern at the age of 18 months. The differences were not significant. In the B whorl pattern, heifers with a high hair whorl crossed more squares, but the difference was not significant in comparison with heifers with a low hair whorl. We found that the time of traversing the maze and the locomotor activity in open-field test may not be influenced in the dairy cattle by the height facial whorl position |
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Brandt, K. (2004). A Language of Their Own: An Interactionist Approach to Human-Horse Communication. Society and Animals, 12(4), 299–316.
Abstract: This paper explores the process of human-horse communication using ethnographic data of in-depth interviews and participant observation. Guided by symbolic interactionism, the paper argues that humans and horses co-create a language system by way of the body to facilitate the creation of shared meaning. This research challenges the privileged status of verbal language and suggests that non-verbal communication and language systems of the body have their own unique complexities. This investigation of humanhorse communication offers new possibilities to understand the subjective and intersubjective world of non-verbal language using beings-human and nonhuman alike.
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Waiblinger, S., Menke, C., Korff, J., & Bucher, A. (2004). Previous handling and gentle interactions affect behaviour and heart rate of dairy cows during a veterinary procedure. Appl. Anim. Behav. Sci., 85(1-2), 31–42.
Abstract: Veterinary and management procedures often are aversive to the animals, resulting in physiological and behavioural stress reactions, which increase the risk of accidents and might lower performance. We investigated the effects of previous positive handling and of gentle interactions during the procedure on behaviour and heart rate in dairy cows during rectal palpation with sham insemination. Twenty cows were allocated randomly into two groups of 10 animals: handling, received additional positive handling over a period of four weeks by one person (handler); control, only routine handling by different caretakers. The week after the handling period, tests lasting 9 min, including 4 min rectal palpation, were carried out with each animal on four successive days in four situations in a balanced order: cow is alone during the test, with the handler, with an usual caretaker, or with an unknown person. Behaviour and heart rate were recorded. Previously handled animals had lower heart rate during tests (P<=0.05, n=19), kicked less when alone (P<=0.05, n=19) and tended to show less restless behaviour (P<=0.1, n=19). Cows were further calmed by gentle interactions during the test, but people differed remarkably. Cows showed less restless behaviour when gentled by the handler, both in the 4 min of rectal palpation and in the 9 min test period (each: P<=0.001, n=19). No significant stress reducing effect was found for the other two persons. In conclusion, stress reactions of cows during rectal palpation/insemination can be reduced by previous positive handling as well as by a person providing positive, gentle interactions during the procedure. The results underline the importance of positive, gentle interactions with the animals to enhance animal welfare and reduce the risk of accidents. They also show that people differ in the success to calm down the animals in aversive situations and indicate the need to investigate the characteristics responsible for the differences and identify the preconditions for a stress reducing effect in future research.
Keywords: Human-animal relationship; Cattle; Handling; Stress; Heart rate; Welfare
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Rousing, T., & Waiblinger, S. (2004). Evaluation of on-farm methods for testing the human-animal relationship in dairy herds with cubicle loose housing systems--test-retest and inter-observer reliability and consistency to familiarity of test person. Appl. Anim. Behav. Sci., 85(3-4), 215–231.
Abstract: The human-animal relationship is an important factor when considering animal welfare at herd level. In the present study, two behavioural tests for the on-farm assessment of the human-animal relationship at herd level of dairy cows housed in loose housing cubicle systems were evaluated with respect to inter-observer reliability, test-retest reliability, effect of familiarity of test person as well as inter-correlation of the two tests. In a voluntary animal approach (VAA) test, the number of cows and the latencies to approach and touch a stationary test person was measured. In an avoidance (AV) test, the cows' avoidance reactions to an approaching test person were categorised. A first study was carried out in 12 commercial Danish and Austrian dairy farms. On each farm, both behaviour tests were carried out on the same day and repeated within 4-5 days. For each test, cows were tested by both an unfamiliar and a familiar test person (the stock-person) and two observers simultaneously registered the animals' test responses. The inter-observer reliability of both behavioural tests was found to be high (VAA: 2.5-m approach r=0.98 (P<0.001) and touch r=0.97 (P<0.001); AV: Kappa coefficientweighted=0.886 (prevalence index for flight distance>=2 m is 0.636)). The cows at herd level showed shortest latency for touching an unfamiliar test person on the first test day (P=0.006). Further, the AV test had a high test-retest reliability (Kappa coefficientweighted=0.503 (prevalence index for flight distance>=2 m is -0.660)) and results indicated no effect of familiarity of test person (Kappa coefficientweighted=0.463 (prevalence index for flight distance>=2 m is -0.677)). In a second study, the correlation between the two behavioural tests (similar measures) was evaluated. On each of 10 commercial Danish dairy farms with loose housing cubicle systems at four repeated sessions, both behaviour tests were carried out on the same day. For each test cows were tested by the stock-person. The VAA and AV tests at herd level were highly correlated (rs=-0.84; P=0.002). The results suggest that the AV test is valid and applicable for on-farm assessment of the human-animal relationship at herd level. This accounts only partly for the VAA test, which seem to be more unclear regarding motivation for the animals' approach behaviour.
Keywords: Cattle welfare; Fearful behaviour; Human-animal relationship
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