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Riedel, J., Buttelmann, D., Call, J., & Tomasello, M. (2006). Domestic dogs (Canis familiaris) use a physical marker to locate hidden food. Anim. Cogn., 9(1), 27–35.
Abstract: Dogs can use the placement of an arbitrary marker to locate hidden food in an object-choice situation. We tested domestic dogs (Canis familiaris) in three studies aimed at pinning down the relative contributions of the human's hand and the marker itself. We baited one of two cups (outside of the dogs' view) and gave the dog a communicative cue to find the food. Study 1 systematically varied dogs' perceptual access to the marker placing event, so that dogs saw either the whole human, the hand only, the marker only, or nothing. Follow-up trials investigated the effect of removing the marker before the dog's choice. Dogs used the marker as a communicative cue even when it had been removed prior to the dog's choice and attached more importance to this cue than to the hand that placed it although the presence of the hand boosted performance when it appeared together with the marker. Study 2 directly contrasted the importance of the hand and the marker and revealed that the effect of the marker diminished if it had been associated with both cups. In contrast touching both cups with the hand had no effect on performance. Study 3 investigated whether the means of marker placement (intentional or accidental) had an effect on dogs' choices. Results showed that dogs did not differentiate intentional and accidental placing of the marker. These results suggest that dogs use the marker as a genuine communicative cue quite independently from the experimenter's actions.
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Pluhácek, j., Bartos, L., & Víchová, J. (2006). Variation In Incidence Of Male Infanticide Within Subspecies Of Plains Zebra (Equus Burchelli). Journal of Mammalogy, 87(1), 35–40.
Abstract: Social organization seems to determine the occurrence of male infanticide in equids. Although, no information concerning social organization of the maneless zebra (Equus burchelli borensis) has been available, we presumed that the occurrence of infanticide would be the same across all subspecies of plains zebra. We examined the occurrence of this phenomenon in 9 herds of 4 subspecies: the maneless zebra, Grant's zebra (E. burchelli boehmi), Chapmann's zebra (E. b. chapmanni), and the Damara zebra (E. b. antiquorum) at 4 zoos. The probability of a foal's death was affected by the presence of a new male and subspecies. Except for the maneless zebra, all subspecies showed existence of male infanticide. We found no occurrence of male infanticide in maneless zebras, which suggests a different social system. This would also support the subspecific status of the maneless zebra.
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Lonsdorf, E. V. (2006). What is the role of mothers in the acquisition of termite-fishing behaviors in wild chimpanzees (Pan troglodytes schweinfurthii)? Anim. Cogn., 9(1), 36–46.
Abstract: This paper explores the role of maternal influences on the acquisition of a tool-using task in wild chimpanzees (Pan troglodytes schweinfurthii) in order to build on and complement previous work done in captivity. Young chimpanzees show a long period of offspring dependency on mothers and it is during this period that offspring learn several important skills, especially how to and on what to forage. At Gombe National Park, one skill that is acquired during dependency is termite-fishing, a complex behavior that involves inserting a tool made from the surrounding vegetation into a termite mound and extracting the termites that attack and cling to the tool. All chimpanzees observed at Gombe have acquired the termite-fishing skill by the age of 5.5 years. Since the mother is the primary source of information throughout this time period, I investigated the influence of mothers' individual termite-fishing characteristics on their offsprings' speed of acquisition and proficiency at the skill once acquired. Mother's time spent alone or with maternal family members, which is highly correlated to time spent termite-fishing, was positively correlated to offspring's acquisition of critical elements of the skill. I also investigated the specific types of social interactions that occur between mothers and offspring at the termite mound and found that mothers are highly tolerant to offspring, even when the behavior of the offspring may disrupt the termite-fishing attempt. However, no active facilitation by mothers of offsprings' attempts were observed.
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Brauer, J., Kaminski, J., Riedel, J., Call, J., & Tomasello, M. (2006). Making inferences about the location of hidden food: social dog, causal ape. J Comp Psychol, 120(1), 38–47.
Abstract: Domestic dogs (Canis familiaris) and great apes from the genus Pan were tested on a series of object choice tasks. In each task, the location of hidden food was indicated for subjects by some kind of communicative, behavioral, or physical cue. On the basis of differences in the ecologies of these 2 genera, as well as on previous research, the authors hypothesized that dogs should be especially skillful in using human communicative cues such as the pointing gesture, whereas apes should be especially skillful in using physical, causal cues such as food in a cup making noise when it is shaken. The overall pattern of performance by the 2 genera strongly supported this social-dog, causal-ape hypothesis. This result is discussed in terms of apes' adaptations for complex, extractive foraging and dogs' adaptations, during the domestication process, for cooperative communication with humans.
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Kaiser, L., Heleski, C. R., Siegford, J., & Smith, K. A. (2006). Stress-related behaviors among horses used in a therapeutic riding program. J Am Vet Med Assoc, 228(1), 39–45.
Abstract: OBJECTIVE: To determine whether therapeutic riding resulted in higher levels of stress or frustration for horses than did recreational riding and whether therapeutic riding with at-risk individuals was more stressful for the horses than was therapeutic riding with individuals with physical or emotional handicaps. DESIGN: Observational study. ANIMALS: 14 horses in a therapeutic riding program. PROCEDURE: An ethogram of equine behaviors was created, and horses were observed while ridden by 5 groups of riders (recreational riders, physically handicapped riders, psychologically handicapped riders, at risk children, and special education children). Number of stress-related behaviors (ears pinned back, head raised, head turned, head tossed, head shaken, head down, and defecation) was compared among groups. RESULTS: No significant differences in mean number of stress-related behaviors were found when horses were ridden by recreational riders, physically handicapped riders, psychologically handicapped riders, or special education children. However, mean number of stress-related behaviors was significantly higher when horses were ridden by the at-risk children. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that for horses in a therapeutic riding program, being ridden by physically or psychologically handicapped individuals is no more stressful for the horses than is being ridden in the same setting by recreational riders. However, at-risk children caused more stress to the horses, suggesting that the time horses are ridden by at-risk children should be limited both daily and weekly.
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Dixon, G., Green, L. E., & Nicol, C. J. (2006). Effect of diet change on the behavior of chicks of an egg-laying strain. J Appl Anim Welf Sci, 9(1), 41–58.
Abstract: Injurious pecking has serious welfare consequences in flocks of hens kept for egg laying, especially when loose-housed. Frequent diet change is a significant risk for injurious pecking; how the mechanics of diet change influence pecking behavior is unknown. This study investigated the effect of diet change on the behavior of chicks from a laying strain. The study included a 3-week familiarity phase: 18 chick pairs received unflavored feed (Experiment 1); 18 pairs received orange oil-flavored (Experiment 2). All chicks participated in a dietary preference test (P); a diet change (DC); or a control group (C), 6 scenarios. All P chicks preferred unflavored feed. In Experiment 1, DC involved change from unflavored to orange-flavored; Experiment 2, orange- flavored to unflavored. Compared with controls, Experiment 2 DC chicks exhibited few behavioral differences; Experiment 1 DC chicks exhibited increased behavioral event rates on Days 1 and 7. They pecked significantly longer at their environment; by Day 7, they showed significantly more beak activity. There was little evidence of dietary neophobia. Change from more preferred to less preferred feed led to increased activity and redirected pecking behavior.
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Boughner, R. L., & Papini, M. R. (2006). Appetitive latent inhibition in rats: preexposure performance does not predict conditioned performance. Behav. Process., 72(1), 42–51.
Abstract: Nonreinforced preexposure to a conditioned stimulus impairs subsequent conditioning with that stimulus. The goal of these studies was to assess the extent to which acquisition performance could be predicted from preexposure performance using a correlational approach. For both preexposure and autoshaping, four measures of performance were computed, including overall average lever pressing, lever pressing in the initial session, percentage change in lever pressing, and slopes. These measures were correlated in a large sample of rats trained in an autoshaping situation. None of the three measures of autoshaping performance was consistently predicted by any of the three measures of preexposure performance. These results are consistent with the view that latent inhibition is not reducible to long-term habituation.
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Kaiser, L., Smith, K. A., Heleski, C. R., & Spence, L. J. (2006). Effects of a therapeutic riding program on at-risk and special education children. J Am Vet Med Assoc, 228(1), 46–52.
Abstract: OBJECTIVE: To determine the effects of a therapeutic riding program on psychosocial measurements among children considered at risk for poor performance or failure in school or life and among children in special education programs. DESIGN: Observational study. POPULATION: 17 at-risk children (6 boys and 11 girls) and 14 special education children (7 boys and 7 girls). PROCEDURE: For the at-risk children, anger, anxiety, perceived self-competence, and physical coordination were assessed. For the special education children, anger and cheerfulness were measured, and the children's and their mothers' perceptions of the children's behavior were assessed. Measurements were made before and after an 8-session therapeutic riding program. RESULTS: For boys enrolled in the special education program, anger was significantly decreased after completion of the riding program. The boys' mothers also perceived significant improvements in their children's behavior after completion of the program. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that an 8-session therapeutic riding program can significantly decrease anger in adolescent boys in a special education program and positively affect their mothers' perception of the boys' behavior.
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Barry, K. L., & Goth, A. (2006). Call recognition in chicks of the Australian brush-turkey (Alectura lathami). Anim. Cogn., 9(1), 47–54.
Abstract: Most birds rely on imprinting and experience with conspecifics to learn species-specific recognition cues. Australian brush-turkeys (Alectura lathami) do not imprint and form no bonds with parents. They hatch asynchronously, disperse widely and meet juvenile conspecifics at an unpredictable age. Nevertheless, in captivity, hatchlings respond to other chicks. A recent study, which involved the use of robotic models, found that chicks prefer to approach robots that emit specific visual cues. Here, we evaluated their response to acoustic cues, which usually play an important role in avian social cognition. However, in simultaneous choice tests, neither 2-day-old nor 9-day-old chicks preferred the choice arm with playback of either chick or adult conspecific calls over the arm containing a silent loudspeaker. Chicks of both age classes, however, scanned their surroundings more during chick playback, and the response was thus consistent in younger and older chicks. We also presented the chicks with robotic models, either with or without playback of chick calls. They did not approach the calling robot more than they did the silent robot, indicating that the combination of visual and acoustic cues does not evoke a stronger response. These results will allow further comparison with species that face similar cognitive demands in the wild, such as brood parasites. Such a comparative approach, which is the focus of cognitive ecology, will enable us to further analyse the evolution and adaptive value of species recognition abilities.
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Candura, S. M., Verni, P., Minelli, C. M., Rosso, G. L., Cappelli, M. I., Strambi, S., et al. (2006). [Occupational risks among public safety and security forces]. G Ital Med Lav Ergon, 28(1), 53–62.
Abstract: The present paper tries to identify the occupational risk factors (physical, chemical, biological, psychological), variable depending on jobs and tasks, to which the heterogeneous public safety/security workers are exposed. The fight against criminality and public order maintenance imply (sometimes fatal) traumatic risks, and expose to psychophysical and sensorial tiring, unfavourable macro- and microclimatic conditions, the risk of baropathy (air navigation, underwater activities), noise (generated by firearms and several other sources), vibrations and shakings (automatic weapons, transport vehicles), the risk of electric injury, ionizing (X and gamma rays) and non-inonizing (ultraviolet rays, microwaves and radiofrequencies, electromagnetic fields) radiations. Chemical hazards include carbon monoxide and other combustion products (fires, urban traffic), substances released in chemical accidents, tear gases, lead (firing grounds, metal works, environmental pollution), solvents, lubrificants and cutting oils (mechanic repair and maintenance), laboratory materials and reagents, irritant and/or sensitizing agents contained in gloves. The main biological risks are tetanus, blood-borne diseases (viral hepatitis, AIDS), aerogenous diseases (e.g., tuberculosis, Legionnaire's disease, epidemic cerebrospinal meningitis), dog- or horse-transmitted zoonosis. Finally, emotional, psychosomatic and behavioural stress-related disorders (e.g., burn-out syndrome, post-traumatic stress disorder) are typically frequent. The presence of numerous and diversified hazards among public safety/security forces imposes the adoption of occupational medicine measures, including risk assessment, health education, technical and environmental prevention, personal protective devices, sanitary surveillance and biological monitoring, clinical interventions (diagnosis, therapy and rehabilitation of occupational accidents and illnesses), prompt medico-legal evaluation of occupational-related compensation claims.
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