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Mallavarapu, S., Stoinski, T. S., Bloomsmith, M. A., & Maple, T. L. (2006). Postconflict behavior in captive western lowland gorillas (Gorilla gorilla gorilla). Am. J. Primatol., 68(8), 789–801.
Abstract: Postconflict (PC) behaviors, including reconciliation and consolation, have been observed in many primate and several nonprimate species. Using the PC-matched control (MC) method, PC behavior was examined in two groups (n=13) of captive western lowland gorillas, a species for which no conflict resolution data have been published. Analyses of 223 conflicts showed significantly more affiliation between former opponents after a conflict when compared to control periods, indicating reconciliation. Results also showed significantly more affiliation between the victim and a third-party after a conflict, indicating consolation. Both solicited and unsolicited consolation were observed. The majority of the affiliative interactions observed for both reconciliation and consolation were social proximity, which suggests that unlike most nonhuman primates, proximity, rather than physical contact, may be the main mechanism for resolving conflicts in western lowland gorillas. PC behavior was not uniform throughout the groups, but rather varied according to dyad type.
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Lee, J., & Paik, M. (2006). Sex preferences and fertility in South Korea during the year of the Horse. Demography, 43(2), 269–292.
Abstract: Since antiquity, people in several East Asian countries, such as China, Japan, and South Korea, have believed that a person is destined to possess specific characteristics according to the sign of the zodiac under which he or she was born. South Koreans, in particular, have traditionally considered that the year of the Horse bears inauspicious implications for the birth of daughters. Using monthly longitudinal data at the region level in South Korea between 1970 and 2003, we found that in the year of the Horse, the sex ratio at birth significantly increased while fertility decreased.
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Christensen, J. W., Rundgren, M., & Olsson, K. (2006). Training methods for horses: habituation to a frightening stimulus. Equine Vet J, 38(5), 439–443.
Abstract: REASONS FOR PERFORMING STUDY: Responses of horses in frightening situations are important for both equine and human safety. Considerable scientific interest has been shown in development of reactivity tests, but little effort has been dedicated to the development of appropriate training methods for reducing fearfulness. OBJECTIVES: To investigate which of 3 different training methods (habituation, desensitisation and counter-conditioning) was most effective in teaching horses to react calmly in a potentially frightening situation. HYPOTHESES: 1) Horses are able to generalise about the test stimulus such that, once familiar with the test stimulus in one situation, it appears less frightening and elicits a reduced response even when the stimulus intensity is increased or the stimulus is presented differently; and 2) alternative methods such as desensitisation and counter-conditioning would be more efficient than a classic habituation approach. METHODS: Twenty-seven naive 2-year-old Danish Warmblood stallions were trained according to 3 different methods, based on classical learning theory: 1) horses (n = 9) were exposed to the full stimulus (a moving, white nylon bag, 1.2 x 0.75 m) in 5 daily training sessions until they met a predefined habituation criterion (habituation); 2) horses (n = 9) were introduced gradually to the stimulus and habituated to each step before the full stimulus was applied (desensitisation); 3) horses (n = 9) were trained to associate the stimulus with a positive reward before being exposed to the full stimulus (counter-conditioning). Each horse received 5 training sessions of 3 min per day. Heart rate and behavioural responses were recorded. RESULTS: Horses trained with the desensitisation method showed fewer flight responses in total and needed fewer training sessions to learn to react calmly to test stimuli. Variations in heart rate persisted even when behavioural responses had ceased. In addition, all horses on the desensitisation method eventually habituated to the test stimulus whereas some horses on the other methods did not. CONCLUSIONS AND POTENTIAL RELEVANCE: Desensitisation appeared to be the most effective training method for horses in frightening situations. Further research is needed in order to investigate the role of positive reinforcement, such as offering food, in the training of horses.
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Petruso, E. J., Fuchs, T., & Bingman, V. P. (2007). Time-space learning in homing pigeons (Columba livia): orientation to an artificial light source. Anim. Cogn., 10(2), 181–188.
Abstract: Time-space learning reflects an ability to represent in memory event-stimulus properties together with the place and time of the event; a capacity well developed in birds. Homing pigeons were trained in an indoor octagonal arena to locate one food goal in the morning and a different food goal in the late afternoon. The goals differed with respect to their angular/directional relationship to an artificial light source located outside the arena. Further, the angular difference in reward position approximated the displacement of the sun's azimuth that would occur during the same time period. The experimental birds quickly learned the task, demonstrating the apparent ease with which birds can adopt an artificial light source to discriminate among alternative spatial responses at different times of the day. However, a novel midday probe session following successful learning revealed that the light source was interpreted as a stable landmark and not as a surrogate sun that would support compass orientation. Probe sessions following a phase shift of the light-dark cycle revealed that the mechanism employed to make the temporal discrimination was prevailingly based on an endogenous circadian rhythm and not an interval timing mechanism.
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Schmidt, R., Amrhein, V., Kunc, H. P., & Naguib, M. (2007). The day after: effects of vocal interactions on territory defence in nightingales. T. J. Anim. Ecol., 76(1), 168–173.
Abstract: 1. Models on territory acquisition and tenure predict that territorial animals benefit by adjusting territorial defence behaviour to previous challenges they had experienced within the socially complex environment of communication networks. 2. Here, we addressed such issues of social cognition by investigating persisting effects of vocal contests on territory defence behaviour in nightingales Luscinia megarhynchos (Brehm). 3. Using interactive playback during nocturnal song of subjects, a rival was simulated to countersing either aggressively (by song overlapping) or moderately (by song alternating) from outside the subjects' territory. Thereby, the time-specific singing strategy provided an experimentally controlled source of information on the motivation of an unfamiliar rival. 4. Expecting that nightingales integrate information with time, the same rival was simulated to return as a moderately singing intruder on the following morning. 5. The results show that the vigour with which male nightingales responded to the simulated intrusion of an opponent during the day depended on the nature of the nocturnal vocal interaction experienced several hours before. 6. Males that had received the song overlapping playback the preceding night approached the simulated intruder more quickly and closer and sang more songs near the loudspeaker than did males that had received a song alternating playback. 7. This adjustment of territory defence strategies depending on information from prior signalling experience suggests that integrating information with time plays an important part in territory defence by affecting a male's decision making in a communication network.
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Reimers, M., Schwarzenberger, F., & Preuschoft, S. (2007). Rehabilitation of research chimpanzees: stress and coping after long-term isolation. Horm Behav, 51(3), 428–435.
Abstract: We report on the permanent retirement of chimpanzees from biomedical research and on resocialization after long-term social isolation. Our aim was to investigate to what extent behavioral and endocrine measures of stress in deprived laboratory chimpanzees can be improved by a more species-typical social life style. Personality in terms of novelty responses, social dominance after resocialization and hormonal stress susceptibility were affected by the onset of maternal separation of infant chimpanzees and duration of deprivation. Chimpanzees, who were separated from their mothers at a younger age and kept in isolation for more years appeared to be more timid personalities, less socially active, less dominant and more susceptible to stress, as compared to chimpanzees with a less severe deprivation history. However, permanent retirement from biomedical research in combination with therapeutic resocialization maximizing chimpanzees' situation control resulted in reduced fecal cortisol metabolite levels. Our results indicate that chimpanzees can recover from severe social deprivation, and may experience resocialization as less stressful than solitary housing.
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Elhay, M., Newbold, A., Britton, A., Turley, P., Dowsett, K., & Walker, J. (2007). Suppression of behavioural and physiological oestrus in the mare by vaccination against GnRH. Aust Vet J, 85(1-2), 39–45.
Abstract: OBJECTIVE: To examine the immunogenicity of an equine immunocontraceptive vaccine and its efficacy in controlling hormone-related behaviour. DESIGN: A total of 24 mares at two sites in Australia were vaccinated with an immunocontraceptive vaccine comprising gonadotrophin releasing hormone (GnRH) conjugated to a carrier protein in immunostimulating complex as an adjuvant. Twelve animals at each site received a placebo of adjuvant alone and served as controls for seasonal oestrus, hormonal and behaviour patterns. Animals were observed for injection site reactions, ovarian and follicular activity, and serum levels of antibody, 17beta-oestradiol and progesterone in the weeks following vaccination. Mares were also examined for oestrous behaviour by teasing with a stallion. RESULTS: All mares responded to vaccination. Two weeks following the second vaccination there was a peak in antibody response to GnRH that declined gradually over the following weeks. Commensurate with the elevated anti-GnRH antibody there was a marked effect on ovarian activity with a reduction in 17beta-oestradiol and progesterone levels in the 24 vaccinated mares. There was also a reduction of oestrus-related behaviour as determined by a teaser stallion. This effect lasted a minimum of 3 months and correlated with the initial level of antibody response. CONCLUSION: Following a conventional two-dose immunisation regime this commercially available equine immunocontraceptive vaccine was effective at inhibiting oestrous behaviour for at least 3 months. This vaccine has a high level of safety since there were no significant local reactions nor were there any adverse systemic responses to vaccination.
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Ulloa, A., Gonzalez-Ceron, L., & Rodriguez, M. H. (2006). Host selection and gonotrophic cycle length of Anopheles punctimacula in southern Mexico. J Am Mosq Control Assoc, 22(4), 648–653.
Abstract: The host preference, survival rates, and length of the gonotrophic cycle of Anopheles punctimacula was investigated in southern Mexico. Mosquitoes were collected in 15-day separate experiments during the rainy and dry seasons. Daily changes in the parous-nulliparous ratio were recorded and the gonotrophic cycle length was estimated by a time series analysis. Anopheles punctimacula was most abundant during the dry season and preferred animals to humans. The daily survival rate in mosquitoes collected in animal traps was 0.96 (parity rate = 0.86; gonotrophic cycle = 4 days). The length of gonotrophic cycle of 4 days was estimated on the base of a high correlation coefficient value appearing every 4 days. The minimum time estimated for developing mature eggs after blood feeding was 72 h. The proportion of mosquitoes living enough to transmit Plasmodium vivax malaria during the dry season was 0.35.
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Singer, R. A., Klein, E. D., & Zentall, T. R. (2006). Use of a single-code/default strategy by pigeons to acquire duration sample discriminations. Learn Behav, 34(4), 340–347.
Abstract: Past evidence that pigeons may adopt a single-code/default strategy to solve duration sample discriminations may be attributable to the similarity between the intertrial interval (ITI) and the retention interval. The present experiments tested whether pigeons would adopt a single-code/default strategy when possible ITI-retention-interval ambiguity was eliminated and sample salience was increased. Previous studies of duration sample discriminations that have purported to show evidence for the use of a single-code/default coding strategy have used durations of 0, 2, and 10 sec (Zentall, Klein, and Singer, 2004). However, the results of Experiment 1 suggest that the use of a 0-sec sample may produce an artifact resulting in inadvertent present/absent sample matching. In Experiment 2, when pigeons were trained with three nonzero duration samples (2, 8, and 32 sec), clear evidence for the use of a single-code/default strategy was found.
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Bell, R. J. W., Kingston, J. K., Mogg, T. D., & Perkins, N. R. (2007). The prevalence of gastric ulceration in racehorses in New Zealand. N Z Vet J, 55(1), 13–18.
Abstract: AIM: To establish the prevalence and factors influencing the prevalence and severity of gastric ulceration in racehorses in New Zealand. METHODS: Horses (n=171) in active training for racing by trainers (n=24) located throughout New Zealand were examined using gastroscopy during 2003 and 2004. Images of the examination were recorded and reviewed, and an ordinal grade based on the severity of gastric ulceration present was assigned, using the grading system proposed by the Equine Gastric Ulcer Council (EGUC). Information about the horses such as age, breed, sex, stabling, time at pasture, pasture quality, and presence of clinical signs consistent with equine gastric ulcer syndrome (EGUS) was recorded. RESULTS: Of the 171 horses in the study, 133 (78%) were Thoroughbreds and 38 (22%) were Standardbreds. Evidence of gastric ulceration was present in 151 (88.3%) of these. Prevalence of ulceration was higher at the lesser curvature (LC) and greater curvature (GC) of the stomach than at the saccus caecus (SC; p<0.01), and ulceration was more severe at the LC than at either the GC (p=0.02) or the SC (p<0.001). The prevalence of ulceration did not differ between the two breeds (p=0.51) or between horses of differing ages (p=0.56). Gastric ulceration was evident in 125/141 (89%) horses kept at pasture for at least 4 h/day, in all 13 (100%) horses kept at pasture full time, and in 16/17 (94%) horses stabled full time. Prevalence and severity of ulceration did not differ between horses stabled full time, kept at pasture for part of the day or kept at pasture full time (p=0.33 and 0.13, respectively), and for horses grazed on pasture severity of ulceration did not vary significantly with the quality of the pasture (p=0.12). Neither prevalence (p=0.26) nor severity (p=0.49) of gastric ulceration varied significantly with duration of training. CONCLUSIONS: The prevalence of gastric ulceration in racehorses in New Zealand is similar to that reported elsewhere for horses in active training for racing. Access to pasture for some or all of the day did not appear to be protective.
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