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Houpt, K. A. (2002). Formation and dissolution of the mare-foal bond. Appl. Anim. Behav. Sci., 78(2-4), 319–328.
Abstract: The behavior of mares at foaling and their behavior during subsequent weekly brief separations from their foals was quantified. Thirteen multiparous pony mares were observed for the first 30 min after foaling. Activities directed toward the foal and toward the fetal membranes were recorded. There were 16+/-8 contacts with the fetal membranes, most in the first 10 min post-partum. There were 81+/-12 activities directed toward the foal. There was a downward trend in foal contacts over the first 30 min. Eight of the 13 mares were observed for the 30-60 min post-partum during which licking and touching the foal continued. Only one of the foals suckled in the first 30 min, but half had suckled by 60 min. Ten mares and foals were separated for 5 min each week for 9 weeks. Although mare responses (neighs and steps) decreased with age of the foal, the foals' responses increased from weeks 1 to 2 and then decreased with foal age. This indicates that foal attachment to the mare is not complete until it is 2 weeks old.
Keywords: Maternal; Horse; Foal; Separation; Ontogeny
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Christensen, J. W., Zharkikh, T., Ladewig, J., & Yasinetskaya, N. (2002). Social behaviour in stallion groups (Equus przewalskii and Equus caballus) kept under natural and domestic conditions. Appl. Anim. Behav. Sci., 76(1), 11–20.
Abstract: The aim of this study was to investigate social behaviour in differently reared stallions in their respective environments; one group of stallions was reared under typical domestic conditions whereas the other group was reared and lives under natural conditions. The domestic group consisted of 19, 2-year-old stallions (Equus caballus), which were all weaned at 4 months of age and experienced either individual or group housing facilities before being pastured with the other similarly aged stallions. The natural living and mixed age group of Przewalski stallions (E. przewalskii) consisted of 13 stallions, most of which were juveniles (n=11, <=4 years; n=2, >9 years). The domestic group was studied in a 4-ha enclosure at the Danish Institute of Agricultural Sciences and the Przewalski group under free-ranging conditions in a 75-ha enclosure in the Askania Nova Biosphere Reserve, Ukraine. Behavioural data was collected during 168 h of direct observation. The occurrence of 14 types of social interactions was recorded and group spacing behaviour was studied using nearest neighbour recordings. In spite of very different environments, reflecting domestic and natural rearing conditions, many similarities in behaviour was found. Play and play fight behaviour was very similar in the two stallion groups. Quantitative differences were found in social grooming since Przewalski stallions groomed more frequently (P=0.004), and in investigative behaviours, since domestic stallions showed more nasal (P=0.005) and body sniffing (P<0.001), whereas Przewalski stallions directed more sniffing towards the genital region (P<0.001). These differences may, however, be attributed to environmental factors and in the period of time the stallions were together prior to the study period. Quantitative differences appeared in some agonistic behaviours (kick threat, P<0.001; and kick, P<0.001), but data do not support earlier findings of Przewalski horses being significantly more aggressive than domestic horses. In general, Przewalski stallions engaged in more social interactions, and they showed less group spacing, i.e. maintained a significantly shorter distance between neighbours (P<0.001). The study indicates that also domestic horses, which have been reared under typical domestic conditions and allowed a period on pasture, show social behaviour, which is very similar to that shown by their non-domestic relatives.
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Strand, S. C., Tiefenbacher, S., Haskell, M., Hosmer, T., McDonnell, S. M., & Freeman, D. A. (2002). Behavior and physiologic responses of mares to short-term isolation. Appl. Anim. Behav. Sci., 78(2-4), 145–157.
Abstract: The aim of this study was to evaluate the behavior and physiologic responses of mares to removal from an established pasture herd and to isolation in a pasture setting for 6 h (Group I, n=5). Responses of mares in Group I were compared to mares that were transported and returned to the herd (Group T, n=5) and to mares moved to the isolation pasture with a companion (Group C, n=5). Behavior was recorded continuously for 6 h on the day before the isolation procedures (baseline, Day 0) and again on the day of the procedure (test, Day 1). Plasma cortisol, white blood cell count (WBC), neutrophil:lymphocyte ratio (N:L), and hematocrit (HCT) were measured once on Day 0 (a.m.) and twice on Day 1 (a.m. and p.m.). Heart rate (HR) was monitored continuously during Day 0 and Day 1. Intradermal response to phytohemagglutinin (PHA) injection was measured 18 h following injection, which was administered at the end of Day 1. Average time spent standing alert increased (P<0.05) in Groups I and C and average time spent grazing decreased (P<0.05) in Group C from Day 0 to Day 1. Also, there was a significant difference between groups (based on a calculated χ2-square value) in the proportion of mares that autogroomed, defecated, urinated, rolled, and whinnied on Day 1. Activity shift rate (ASR) and temperament scores increased significantly in Groups I and C from Day 0 to Day 1 (P<0.05). Plasma cortisol increased significantly in all groups from Day 0 to Day 1, a.m. (P<0.05) and decreased significantly from Day 1, a.m. to Day 1, p.m. (P<0.05). HCT significantly increased in all three groups from Day 0 to Day 1, a.m. (P<0.05). WBC significantly increased in Group T from Day 0 to Day 1, a.m. (P<0.05). N:L ratio significantly increased in Groups I and C from Day 0 and Day 1, a.m. to Day 1, p.m. (P<0.05). A variety of measures did indicate a response to removal from the pasture group, however, the overall, short-term response was minimal. Since the responses of Groups I and C were similar, the effects of isolation versus a novel environment or separation from the established herd could not be differentiated.
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Giraldeau, L. - A., Valone, T., J., & Templeton, J., J. (2002). Potential disadvantages of using socially acquired information. Phil. Trans. Biol. Sci., 357(1427), 1559–1566.
Abstract: The acquisition and use of socially acquired information is commonly assumed to be profitable. We challenge this assumption by exploring hypothetical scenarios where the use of such information either provides no benefit or can actually be costly. First, we show that the level of incompatibility between the acquisition of personal and socially acquired information will directly affect the extent to which the use of socially acquired information can be profitable. When these two sources of information cannot be acquired simultaneously, there may be no benefit to socially acquired information. Second, we assume that a solitary individual's behavioural decisions will be based on cues revealed by its own interactions with the environment. However, in many cases, for social animals the only socially acquired information available to individuals is the behavioural actions of others that expose their decisions, rather than the cues on which these decisions were based. We argue that in such a situation the use of socially acquired information can lead to informational cascades that sometimes result in sub-optimal behaviour. From this theory of informational cascades, we predict that when erroneous cascades are costly, individuals should pay attention only to socially generated cues and not behavioural decisions. We suggest three scenarios that might be examples of informational cascades in nature.
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Fischer, J., Hammerschmidt, K., Cheney, D. L., & Seyfarth, R. M. (2002). Acoustic features of male baboon loud calls: influences of context, age, and individuality. J Acoust Soc Am, 111(3), 1465–1474.
Abstract: The acoustic structure of loud calls (“wahoos”) recorded from free-ranging male baboons (Papio cynocephalus ursinus) in the Moremi Game Reserve, Botswana, was examined for differences between and within contexts, using calls given in response to predators (alarm wahoos), during male contests (contest wahoos), and when a male had become separated from the group (contact wahoos). Calls were recorded from adolescent, subadult, and adult males. In addition, male alarm calls were compared with those recorded from females. Despite their superficial acoustic similarity, the analysis revealed a number of significant differences between alarm, contest, and contact wahoos. Contest wahoos are given at a much higher rate, exhibit lower frequency characteristics, have a longer “hoo” duration, and a relatively louder “hoo” portion than alarm wahoos. Contact wahoos are acoustically similar to contest wahoos, but are given at a much lower rate. Both alarm and contest wahoos also exhibit significant differences among individuals. Some of the acoustic features that vary in relation to age and sex presumably reflect differences in body size, whereas others are possibly related to male stamina and endurance. The finding that calls serving markedly different functions constitute variants of the same general call type suggests that the vocal production in nonhuman primates is evolutionarily constrained.
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Okamoto, S., Tomonaga, M., Ishii, K., Kawai, N., Tanaka, M., & Matsuzawa, T. (2002). An infant chimpanzee (Pan troglodytes) follows human gaze. Anim. Cogn., 5(2), 107–114.
Abstract: The ability of non-human primates to follow the gaze of other individuals has recently received much attention in comparative cognition. The aim of the present study was to investigate the emergence of this ability in a chimpanzee infant. The infant was trained to look at one of two objects, which an experimenter indicated by one of four different cue conditions: (1) tapping on the target object with a finger; (2) pointing to the target object with a finger; (3) gazing at the target object with head orientation; or (4) glancing at the target object without head orientation. The subject was given food rewards independently of its responses under the first three conditions, so that its responses to the objects were not influenced by the rewards. The glancing condition was tested occasionally, without any reinforcement. By the age of 13 months, the subject showed reliable following responses to the object that was indicated by the various cues, including glancing alone. Furthermore, additional tests clearly showed that the subject's performance was controlled by the “social” properties of the experimenter-given cues but not by the non-social, local-enhancing peripheral properties.
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Kuroshima, H., Fujita, K., Fuyuki, A., & Masuda, T. (2002). Understanding of the relationship between seeing and knowing by tufted capuchin monkeys (Cebus apella). Anim. Cogn., 5(1), 41–48.
Abstract: The ability of four tufted capuchin monkeys (Cebus apella) to recognize the causal connection between seeing and knowing was investigated. The subjects were trained to follow a suggestion about the location of hidden food provided by a trainer who knew where the food was (the knower) in preference to a trainer who did not (the guesser). The experimenter baited one of three opaque containers behind a cardboard screen so that the subjects could not see which of the containers hid the reward. In experiment 1, the knower appeared first in front of the apparatus and looked into each container; next, the guesser appeared but did not look into any containers. Then the knower touched the correct cup while the guesser touched one of the three randomly. The capuchin monkeys gradually learned to reach toward the cup that the knower suggested. In experiment 2, the subjects adapted to a novel variant of the task, in which the guesser touched but did not look into any of the containers. In experiment 3, the monkeys adapted again when the knower and the guesser appeared in a random order. These results suggest that capuchin monkeys can learn to recognize the relationship between seeing and knowing.
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Haruta, N., & Kitagawa, T. (2002). Time-resolved UV resonance Raman investigation of protein folding using a rapid mixer: characterization of kinetic folding intermediates of apomyoglobin. Biochemistry, 41(21), 6595–6604.
Abstract: The 244-nm excited transient UV resonance Raman spectra are observed for the refolding intermediates of horse apomyoglobin (h-apoMb) with a newly constructed mixed flow cell system, and the results are interpreted on the basis of the spectra observed for the equilibrium acid unfolding of the same protein. The dead time of mixing, which was determined with the appearance of UV Raman bands of imidazolium upon mixing of imidazole with acid, was 150 micros under the flow rate that was adopted. The pH-jump experiments of h-apoMb from pH 2.2 to 5.6 conducted with this device demonstrated the presence of three folding intermediates. On the basis of the analysis of W3 and W7 bands of Trp7 and Trp14, the first intermediate, formed before 250 micros, involved incorporation of Trp14 into the alpha-helix from a random coil. The frequency shift of the W3 band of Trp14 observed for this process was reproduced with a model peptide of the A helix when it forms the alpha-helix. In the second intermediate, formed around 1 ms after the start of refolding, the surroundings of both Trp7 and Trp14 were significantly hydrophobic, suggesting the formation of the hydrophobic core. In the third intermediate appearing around 3 ms, the hydrophobicity was relaxed to the same level as that of the pH 4 equilibrium intermediate, which was investigated in detail with the stationary state technique. The change from the third intermediate to the native state needs more time than 40 ms, while the appearance of the native spectrum after the mixing of the same solutions was confirmed separately.
Keywords: Animals; Apoproteins/*chemistry; Circular Dichroism; Holoenzymes/chemistry; Horses; Hydrochloric Acid/chemistry; Hydrogen-Ion Concentration; Imidazoles/chemistry; Kinetics; Models, Molecular; Myoglobin/*chemistry; Peptide Fragments/chemistry; *Protein Folding; Protein Structure, Secondary; Spectrum Analysis, Raman/*methods; Tryptophan/*chemistry; Ultraviolet Rays; Whales
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Byrne, R. W. (2002). Imitation of novel complex actions: What does the evidence from animals mean? In C. T. Snowdon, T. J. Roper, & J. S. Rosenblatt (Eds.), Advances in the Study of Behavior (Vol. 31, pp. 77–105). San Diego: Academic Press.
Abstract: Summary Underlying the various behaviors that are classified as imitation, there may be several distinct mechanisms, differing in adaptive function, cognitive basis, and computational power. Experiments reporting “true motor imitation” in animals do not as yet give evidence of production learning by imitation; instead, contextual imitation can explain their data, and this can be explained by a simple mechanism (response facilitation) which matches known neural findings. When imitation serves a function in social mimicry, which applies to a wide range of phenomena from neonatal imitation in humans and great apes to pair-bonding in some bird species, the fidelity of the behavioral match is crucial. Learning of novel behavior can potentially be achieved by matching the outcome of a model's action, and it is argued that vocal imitation by birds is a clear example of this method (which is sometimes called emulation). Alternatively, the behavior itself may be perceived in terms of actions that the observer can perform, and thus it may be copied. If the imitation is linear and stringlike (action level), following the surface form rather than the underlying plan, then its utility for learning new instrumental methods is limited. However, the underlying plan of hierarchically organized behavior is visible in output behavior, in subtle but detectable ways, and imitation could instead be based on this organization (program level), extracted automatically by string parsing. Currently, the most likely candidates for such capacities are all great apes. It is argued that this ability to perceive the underlying plan of action, in addition to allowing highly flexible imitation of novel instrumental methods, may have resulted in the competence to understand the intentions (theory of mind) of others.
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Morgan, K., Funkquist, P., & Nyman, G. (2002). The effect of coat clipping on thermoregulation during intense exercise in trotters. Equine Veterinary Journal, 34(S34), 564–567.
Abstract: Summary The aim of this study was to study the physiological, especially thermoregulatory, responses during intense exercise in the clipped horse compared to the horse with winter coat. Six Standardbred trotters were studied before and after clipping. They performed an inclined incremental high intensity treadmill exercise test and were monitored during recovery. The clipped horse differed significantly (ANOVA) during exercise as compare to coated: less increase in central venous blood temperature, higher skin surface temperature, greater difference skin to ambient temperature and higher rate of nonevaporative heat loss. The clipped horse had significantly lower total cutaneous evaporative heat loss from walk to end of peak exercise and a shorter time for recovery for the respiratory rate using a paired t test. The clipped horse showed a tendency (P = 0.059) to decreased oxygen uptake during the stepwise increase in workload. We concluded that the clipped horse experienced less strain on the thermoregulatory system due to an enhanced heat loss. Some clipped horses in the study showed a more efficient power output; future studies with emphasis on respiration and oxygen demand are needed to explain this.
Keywords: horse; thermoregulation; heat loss; recovery; blood temperature; oxygen uptake
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