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1.
The activity budget hypothesis has been proposed to explain the social segregation commonly observed in ungulate populations. This hypothesis suggests that differences in body size – i.e. between dimorphic males and females – may account for differences in activity budget. In particular, if females spend more time grazing and less time resting than males, activity synchrony would be reduced. Increased costs of maintaining synchrony despite differences in activity budget would facilitate group fragmentation and instability of mixed-sex groups. In this paper two prerequisites of the activity budget hypothesis were tested: (1) that males should spend less time feeding and more time resting than females in single-sex groups and (2) that lower activity synchrony should be observed in mixed-sex compared to single-sex groups. The activity budget and synchrony in mixed and single-sex groups of merino sheep (Ovis aries) of different sizes (2, 4, 6, 8 individuals) were measured in three contiguous 491-m2 arenas located in a natural pasture. Three same-size groups, one of each category, were observed simultaneously. We found no sexual differences in the time spent inactive and active (i.e. grazing, standing, moving, interacting). Males spent significantly more time grazing and less time standing than females. These differences disappeared when yearling males were omitted from the group. Males and females had similar bite and step rates. Sheep of both sexes spent less time resting and more time grazing and moving and had lower bite rates when in mixed-sex groups than when in single-sex groups. The synchrony among visually isolated groups was near zero, indicating that they changed activities independently. On the contrary, within-group synchrony was high; however it was higher in single-sex groups, in particular for males, than in mixed-sex groups. Our results suggest that differences in activity budget and synchrony alone are insufficient to explain social segregation.  相似文献   

2.
半圈养条件下白唇鹿行为时间分配及活动规律的研究   总被引:10,自引:3,他引:10  
白唇鹿 (Cervus albirostris)是我国青藏高原特有种 ,在鹿类进化史上极其重要。因其药用价值很高 ,几十年来捕杀现象严重 ,数量大为减少 ,濒于灭绝 ,1 988年被列为国家一级保护动物 [13 ] 。目前白唇鹿分布在 2 9°~ 40°N,92°~ 1 0 2°E的区域内[1] 。它们主要活动于海拔 350 0~ 50 0 0 m之间的高寒半荒漠草原 ,高山草甸草原和亚高山灌丛草原 [7] 。国内对白唇鹿的研究 ,涉及到食性[7,11] 、繁殖[3~ 5] 、形态、生态地理分布[6] 等 ,而对白唇鹿非发情期行为时间分配尚无报道。 1 998年 3~ 4月我们在上海野生动物园对其进行了专题研…  相似文献   

3.
We developed an automated method using depth and one axis of body acceleration data recorded by animal-borne data loggers to identify activities of penguins over long-term deployments. Using this technique, we evaluated the activity time budget of emperor penguins (n = 10) both in water and on sea ice during foraging trips in chick-rearing season. During the foraging trips, emperor penguins alternated dive bouts (4.8±4.5 h) and rest periods on sea ice (2.5±2.3 h). After recorder deployment and release near the colony, the birds spent 17.9±8.4% of their time traveling until they reached the ice edge. Once at the ice edge, they stayed there more than 4 hours before the first dive. After the first dive, the mean proportions of time spent on the ice and in water were 30.8±7.4% and 69.2±7.4%, respectively. When in the water, they spent 67.9±3.1% of time making dives deeper than 5 m. Dive activity had no typical diurnal pattern for individual birds. While in the water between dives, the birds had short resting periods (1.2±1.7 min) and periods of swimming at depths shallower than 5 m (0.25±0.38 min). When the birds were on the ice, they primarily used time for resting (90.3±4.1% of time) and spent only 9.7±4.1% of time traveling. Thus, it appears that, during foraging trips at sea, emperor penguins traveled during dives >5 m depth, and that sea ice was primarily used for resting. Sea ice probably provides refuge from natural predators such as leopard seals. We also suggest that 24 hours of sunlight and the cycling of dive bouts with short rest periods on sea ice allow emperor penguins to dive continuously throughout the day during foraging trips to sea.  相似文献   

4.
Pregnant and lactating pony mares were observed in two environments, stable and pasture. Twenty-six pony mares were observed on pasture for 2 weeks before and after parturition. The behavior of each mare was recorded every 30 min from 18.00 to 06.00 h. The mutually exclusive behaviors were standing (either standing alert or standing at rest with a hindlimb flexed), grazing (prehending or masticating grass), walking, lying in sternal recumbency and lying in lateral recumbency. The total time-budget for prepartum mares on pasture was 55.3 ± 4.1% grazing, 32.9 ± 3.3% standing, 6.0 ± 1.5% lying in sternal recumbency, 2.7 ± 0.7% walking and 1.4 ± 0.6% lying in lateral recumbency. Grazing and standing occurred at all times, but grazing was most common from 18.00 to 21.00 h and after 05.00 h. Lying was most common between 01.00 and 04.00. Lying in lateral recumbency occurred only after dark, in pre-partum mares. The total time-budget for post-partum mares on pasture was 68.6 ± 4.0% grazing, 22.5 ± 3.0% standing, 4.7 ± 1.0% walking, 4.2 ± 1.2% lying in sternal recumbency and 0.2 ± 0.2% lying in lateral recumbency. Lying in lateral recumbency was seen only at 18.00 h. Lying in sternal recumbency occurred between 21.00 and 04.30 h. More time was spent grazing by the post-partum mares than by the pre-partum mares.The same behaviors were recorded for stabled pony mares except that eating hay rather than grazing constituted the ingestive behavior quantified. The total time-budget for pregnant stabled ponies was 71 ± 3% standing, 15 ± 3% eating, 0.5 ± 0% lying in lateral recumbency, 0.5 ± 0.2% walking and 12.1 ± 2.3% lying in sternal recumbency. Eating decreased and standing increased during the night. Most lying was seen between 01.30 and 05.00 h. Lying in lateral recumbency occurred between 19.30 and 03.30 h. The total nocturnal time-budget of post-partum stalled ponies was 67 ± 3% eating, 19 ± 3% standing and 13.0 ± 2.3% lying in sternal recumbency. Post-partum mares were not observed to walk or to lie in lateral recumbency.The change in behavior after parturition may reflect: (1) nutritional demands of lactation; (2) maternal protective behavior; (3) response to seasonal changes in the environment.  相似文献   

5.
在半圈养条件下冬季长颈鹿日活动格局   总被引:6,自引:0,他引:6  
2002年11月~2003年1月,采用随机和焦点动物法对长颈鹿的日活动格局做了观察。结果表明:摄食是越冬的主要行为,相对集中在昼间呈锯齿状多高峰均匀的采食节律,其次是反刍和卧息,最少是站立;孕鹿趋向于站立反刍并减少移动时间;雄鹿以最少的摄食时间获得最大的干物质净收益,昼间趋向于维持站立姿势而夜间趋向于卧息。  相似文献   

6.
One of the fundamental questions in animal ecology concerns the activity pattern of animals and the environmental and intrinsic factors that influence such dynamics. This study tested the hypotheses that activity time budgets of the African buffalo appeared to vary by season and times of day and predicted that buffalo would express unequal proportion of time for different activity patterns during the wet and dry seasons in Chebera Churchura National Park (CCNP). An investigation on the diurnal activity budget of the African buffalo was carried out during the wet and dry seasons of 2012–2014 in the Chebera Churchura National Park, Ethiopia, using focal‐animal sampling method. Buffalo spent a greater proportion of the time in feeding and resting/ruminating activities in both the wet and dry seasons. Feeding and resting (lying down and standing) were the predominant activities (87.14% of the diurnal active period), 48.95% time spent feeding during the dry season and 44.91% during the wet season. There was a significant decrease in feeding and an increase in resting from dry seasons to wet seasons. Daytime grazing and resting periods during the wet season were estimated to be 5.39 h and 4.98 h, respectively. Morning and the late afternoon activity peaks were more pronounced during the dry season than the wet season. Therefore, feeding and resting time was influenced by the time of day and the seasons. But there were no significant difference in time allocation for other activities in both the wet and dry seasons. The study has implications for understanding animal activity budget across species, particularly relationships between temperature and season.  相似文献   

7.
2011年6~8月,在北京市野生动物救护中心露天笼舍内,采用瞬时扫描法对笼养条件下的4只大斑啄木鸟(Dendrocopos major)行为时间分配和活动节律进行了研究,利用单因素方差分析来说明不同性别大斑啄木鸟间行为时间分配差异以及研究对象在日间不同时间段行为节律差异.结果显示,笼养条件下大斑啄木鸟的各种行为活动具有一定的时间分配特点和日行为节律.大斑啄木鸟的行为主要表现为休息和飞行走动,占全部行为的36.24%和26.96%,其次为觅食行为,占17.69%.除觅食、理羽和其他行为外,雌雄间行为时间分配差异不显著(P>0.05).大斑啄木鸟昼间活动的高峰期出现在上午,中午有午休现象,日间行为节律明显.飞行走动、休息、理羽、跳跃行为的发生频次在雌雄间无显著差异(P>0.05),而雄性觅食的发生频次显著地大于雌性的(P<0.05).  相似文献   

8.
Upright and recumbent rest of 15 Welsh pony foals and their mothers was studied over a 2 year period. During their first week of life, the foals spent 32% of the time in recumbent rest. Subsequently, the percentage of time spent in recumbent rest decreased, but was still greater than for the foal's mother by Week 21, when the foals spent 6.5% of their time in recumbent rest. Adults spent little time in recumbent rest. Foals rested upright only 3.5% of the time during their first week of life. Mares rested upright more than foals did to Week 13, at which time peak values for time spent in upright rest occurred for both mares (32.5%) and foals (23%). Subsequently, mares and foals spent equal, but decreasing, amounts of time resting upright. The total time spent resting by the foals decreased gradually, and was characterized by a transition from recumbent rest to upright rest. Foals were more likely to be resting, either recumbent or upright, if their mother was resting upright. During the late spring, summer, and early autumn, mares and foals were most likely to be resting upright between 09:00 and 17:00 h.  相似文献   

9.
The effect of shade on behavior and physiological attributes of grazing cows in a high altitude subtropical zone is not well established. This work aimed to investigate how social and ingestive behaviors, as well as physiological and other attributes of dairy cows such as milk production, change in a subtropical environment during the hot season either with or without free access to shade. Fourteen lactating cows were kept on pasture either with no shade or with free access to shade for 5 days and their behavior was recorded with instantaneous scan sampled every 10 min, from sunrise, 0530 h (Greenwich mean time, GMT−0200 h) to sunset, 2100 h (GMT−0200 h). Behavior traits included (1) time spent in activities such as grazing, ruminating, resting, lying, standing, walking, seeking shade and staying in the proximity to the water trough and (2) number of events such as water ingestion, aggressive interactions, as well as competition for shade and water. Physiological attributes such as heart and respiratory rates, rectal temperature, number of rumen movements, panting score, as well as milk yield, were evaluated. Time spent in behavioral activities, number of behavioral events and physiological attributes varied between groups (with and without access to shade). Cows with no shade showed increased respiratory and heart rates and panting score at 1300 h, higher values for time of permanence near the water trough, number of competition and aggression events for shade. On the other hand, they showed lower values for time spent resting while lying, ruminating while standing, seeking shade. Access to shade did not change time spent lying, standing, walking with the head up, ruminating while lying, resting while standing, as well as milk yield and number of ruminal movements. Significant interactions between access to shade and days of measurements were detected for time spent walking, ruminating, grazing, resting, number of water ingestion events, competition events near the water trough and for shade, as well as for rectal temperature and panting score measured at 1700 h. In the high altitude subtropical region, access to shade minimizes negative heat stress effects on behavior and physiological aspects of dairy cows.  相似文献   

10.
非笼养雌雄东北虎的行为时间分配和活动节律的比较   总被引:3,自引:1,他引:2  
1998 年4 月至2001 年4 月, 采用随机取样法、目标取样法和扫描取样法对黑龙江东北虎林园的10 只(5 雌5 雄) 非笼养东北虎的昼间行为时间分配及活动节律进行了研究。结果表明, 雌雄东北虎的行为时间分配和活动节律均存在一定的差异。在时间分配方面, 雌性每天用于休息、社会和其它(包括饮水、排遗和修饰) 行为的时间多于雄性, 雌性每天用于活动和取食的时间少于雄性, 只有站立比较接近。对雌雄各种行为的单因素方差分析表明, 雌雄的休息、活动和其它行为存在极显著差异, 取食存在显著差异, 站立和社会行为不存在显著差异。在活动节律方面, 雌雄的活动变化规律相似, 仅在出现和持续时间及强度上存在差异。用单因素方差分析法对不同季节东北虎的各种行为进行检验, 发现季节因素对取食和社会行为影响极显著, 对休息、活动和站立影响显著。  相似文献   

11.
Environmental factors have strong influence on activity of alpine ungulates. However, the presence and activities of people in high mountains have been growing rapidly and have led to the advent of human-induced factors, which may modify the time budget. In this study, we examined the influence of natural and human-induced factors on the daytime budget of Tatra chamois Rupicapra rupicapra tatrica. On average, chamois spent 46% of their time foraging, 40% resting, 13% moving around and 1% on social behaviour. The amount of time devoted to particular categories of behaviour was influenced by the time of day, herd size, weather conditions and human disturbance. Human disturbance and the time of day had the highest effect on the proportion of foraging in the daytime budget, which increased as the day progressed and at greater distances from the nearest hiking trail. These two factors also increased the amount of time spent resting, which peaked during the afternoon hours and at greater distances from the nearest trail. The time spent moving around decreased with increasing herd size, distance from the nearest trail and as the day progressed. Males devoted less time to foraging and more to resting and moving around than females. The intensity of human-induced factors is particularly important for a population inhabiting a small, isolated area, as is the case with strictly high-mountain species.  相似文献   

12.
湖北石首麋鹿昼间活动时间分配   总被引:1,自引:1,他引:1  
为探讨性别、年龄和季节对麋鹿(Elaphurus davidianus)行为的影响,2006年9月-2007年10月,作者采用焦点取样法和瞬时记录法,将麋鹿昼间活动归为采食、饮水、运动、休息、警觉、其他行为等六大类型,每月6-8 d对湖北石首麋鹿国家级自然保护区麋鹿种群的昼间活动时间分配进行了跟踪观察.结果表明:麋鹿有晨、昏两个采食高峰和一个午间休息期,各种行为类型所占比例依次是:休息53.40%(±5.59%)、采食22.36(±8.34%)、运动11.23%(±0.63%)、警觉5.03%(±1.76%)、其他行为4.42%(±2.06%),饮水2.65%(±0.74%).不同季节,时间分配变化明显.非参数Kruskal Wallis H检验结果显示(n=120),季节、年龄和性别显著影响麋鹿的活动时间分配.除运动行为(x2=16.856,df=3,P>0.05)和饮水行为(x2=7.667,df=3,P>0.05)无显著差异外,采食(x2=15.657,df=3,P<0.01)、休息(x2=13.173,df=3,P<0.01)、警觉(x2 =13.887,df=3,P<0.01)和其他行为(x2=16.317,df=3,P<0.01)在不同季节所占时间百分比均有极显著差异.对不同性别年龄组的活动时间分配采用两个独立样本的Mann-Whitney U检验,各性别-年龄组间的运动行为所占时间比例有极显著差异(P<0.01),雄鹿与雌鹿之间的警觉行为有极显著差异(P<0.01),雄鹿花较多时间用于警觉.幼鹿与成年鹿及亚成年鹿之间的采食行为时间有极显著差异(P<0.01).不同性别、年龄组在不同季节的昼间活动时间分配的差异采用方差(ANOVA)分析后发现:所有年龄组,夏季与冬季饮水、春季与夏季警觉均存在显著性差异(P<0.01);成体和亚成体麋鹿,春季与冬季警觉、夏季与冬季运动均存在显著性差异(P<0.01).  相似文献   

13.
赵序茅  马鸣  张同 《动物学杂志》2013,48(6):942-946
2012年7~11月,采用焦点动物取样法和瞬时扫描法,在乌鲁木齐近郊水域白湖,对白眼潜鸭(Aythya nyroca)秋季行为进行实地观察研究。制定出白眼潜鸭行为谱,各种行为有取食、保养、运动、休息、警戒、其他,共6类14种。昼间各行为时间分配依次为取食(56.7%)、运动(13.8%)、保养(11.8%)、休息(11.2%)、警戒(5.1%)、其他(1.4%)。其中取食、休息、运动行为有明显的节律性变化。休息行为以家庭为单位聚集在一起进行,取食行为则分开进行。7~9月份7:00~8:00时、18:00~19:00时休息行为出现峰值,10~11月份8:00~9:00时、17:00~18:00时出现峰值;7~9月份取食行为在8:00~9:00时、17:00~18:00时有明显的峰值,10~11月份在10:00~11:00时和15:00~16:00时出现峰值;7~11月份运动行为均在中午达到峰值。白眼潜鸭7~9月份与10~11月份觅食行为、休息行为和保养行为差异极显著(P<0.01),运动行为无显著性差异(P >0.05)。迁徙前(10月中旬),白眼潜鸭有集群现象,数量最多达到37只,10月下旬种群集体迁徙。秋季白眼潜鸭主要时间用于取食,意图为了迁徙或越冬积累能量,集群迁徙有利于种群防御天敌。  相似文献   

14.
2007年11月、12月和2008年3月,在内蒙古达赉湖地区,采用扫描取样法对雌雄蒙原羚繁殖期及其前后昼间行为时间分配进行了研究。 研究表明:(1)繁殖期前、繁殖期和繁殖期后,雌性蒙原羚采食时间,占昼间活动时间的比例分别为(44.9±3.8)%、(43.5±4.0)% 和 (46.2±3.1)%;卧息时间,占昼间活动时间的比例分别 为(32.3±4.8)%、(29.2±2.9)% 和 (28.0±4.8)%;雌性蒙原羚在繁殖期及其前后采食、移动和卧息的行为时间分配差异不显著(P>0.05),站立、繁殖、“其他”行为时间分配差异性显著(P<0.05)。(2)繁殖期前、繁殖期和繁殖期后, 雄性蒙原羚采食时间,占昼间活动时间的比例分别为 (52.6±3.8)%、(17.5±2.8)% 和 (29.8±4.8)%;卧息时间,占昼间活动时间的比例分别为 (13.4±6.4)%、(24.2±4.1)% 和 (44.2±4.7)%。雄性蒙原羚在繁殖期及其前后采食、卧息、站立、移动、繁殖、“其他”时间分配均有显著差异(P<0.05)。动物采食卧息的行为时间分配反映动物的能量平衡策略。雌性蒙原羚的时间分配表明,雌性蒙原羚的能量平衡策略在繁殖期前、繁殖期和繁殖期后没有发生显著变化,均为能量摄入最优化策略,尽可能多的时间分配在采食上;雄性蒙原羚的时间分配表明,在繁殖期前,其能量平衡策略为能量摄入最优化策略,尽可能多的时间分配在采食上;雄性蒙原羚繁殖期及繁殖期后其能量平衡策略转变为能量支出优化策略,尽可能少的支出能量,尽可能多的时间分配在卧息上。  相似文献   

15.
Open-field test behaviors of 5 barrows and 5 gilts from each of two housing treatments (N = 20) were recorded for 5-min periods. The hogs had been housed in their respective systems (pasture or concrete floor) for 6 weeks and averaged 18 weeks old at the time of the experiment. The 38 × 198-m pasture (P) contained approximately 70% grass of grazeable length and housed 49 pigs. The 3.7 × 7.6-m concrete feeding floor (FF) was located in an open-front building and housed 34 pigs. The open-field tests were conducted in a 3 × 12-m enclosure on pasture. Data collected include time spent chewing, grazing, nudging, sniffing or rooting, number of vocalizations, and time spent lying, standing walking or trotting. FF pigs spent more time grazing and chewing than did P pigs. Standing time was also greater for FF pigs. Only P pigs lay down during the test period. These findings suggest an increased specific-action potential for grazing behaviors resulted from maintaining the hogs in an indoor housing facility.  相似文献   

16.
笼养灰胸竹鸡的活动时间分配   总被引:2,自引:0,他引:2  
采用直接观察法对灰胸竹鸡在笼养条件下的活动时间分配及行为特点进行研究,结果表明笼养条件下灰胸竹鸡的主要行为有走动、站立、取食、静卧4种,一天中有两个活动高峰,雄鸡的活动强于雌鸡;白天休息时间占40%以上,采食集中在上午和傍晚进行;站立、取食、静卧发生的频次在雌雄之间无显著差异(P〉0.05),而走动的频次雄鸡极显著的高于雌鸡(P〈0.01),各行为每频次在持续时间上差异不显著(P〉0.05)。  相似文献   

17.
蒙古野驴昼间行为的时间分配   总被引:7,自引:0,他引:7  
2005年3月至2006年6月,研究了内蒙古中部中蒙边境地区蒙古野驴(Eqqus hemionus hemionus)的昼间行为及时间分配,并建立了蒙古野驴的昼间行为谱。统计分析表明,蒙古野驴用于取食的时间最多,平均超过50%,其次是站立。蒙古野驴在冬春季节(11月至次年4月)取食时间明显长于夏秋季(5~10月)。蒙古野驴一天中7:00~10:00时和16:00~18:00时为取食高峰期,11:00~14:00时为其站立和休息高峰,蒙古野驴的其他行为没有明显的高峰期。雌雄蒙古野驴昼间行为时间分配的统计分析表明,取食、运动、卧息和站立凝视无显著的性别差异,而争斗和其他行为两性的差异显著。蒙古野驴昼间用于取食的时间最长,冬春季取食时间(53·95%)多于夏秋季(48·92%)。冬春季,蒙古野驴减少了运动和站立的时间,用于卧息的时间略有增加,中午前后两个取食高峰的间隔时间明显短于夏秋季。蒙古野驴通常在草原的开阔区域取食和移动,在背风和较为隐蔽处卧息。作者进行野外观察时,蒙古野驴对观察者表现出高度的警惕。  相似文献   

18.
2008 年3 ~7 月,在上海市浦东新区华夏公园进行獐重引入试点,采用瞬时扫描取样法和全事件记录法,对圈养条件下24 只獐(12 雌,12 雄)春夏季昼间行为时间分配及活动节律进行了观察。结果表明:休息是春夏季最主要的行为方式,其次是摄食和运动。獐的昼间行为具有明显的节律性,以晨昏活动为主,主要活动时间集中在06:00 ~08:00 和16:00 ~18:00。单因素方差分析(One-way ANOVA analysis)和Mann-Whitney U 检验表明,在时间分配上,春、夏季休息、站立、排遗、梳理和运动行为差异极显著;雌雄间休息、站立、反刍、梳理和警戒行为差异极显著。雌性春、夏季站立、排遗、梳理、运动和社会行为差异极显著,摄食差异显著;雄性春、夏季休息、摄食、梳理、警戒和社会行为差异极显著,站立、反刍、排遗和运动行为差异显著。本研究结果表明重引入獐的行为时间分配和活动节律与野生种群相似,动物福利得到较好满足,对下一步在上海地区的种群复壮和迁地野放等具有重要意义。  相似文献   

19.
Microplitis croceipes (Cresson) females were observed between 06:00 and 20:00 hours in cages containing spring host plants infested withHeliothis virescens (F.), tobacco budworm, larvae, Cages containedGeranium dissectum L. andTrifolium incarnatum L. in plantings of equal area, each infested with 50H. virescens larvae. A time budget for the various behaviors exhibited by the wasps was obtained. In order of decreasing time spent,M. croceipes females were observed to exhibit standing still, searching on plant surface, preening, oriented flight, general flight, and walking. The proportion of time spent preening increased over the day. Oriented flight, general flight, searching, and walking peaked in the morning between 09:00 and 12:00 hours. Oriented flight, general flight, and walking showed minor increases in the afternoon.Microplitis croceipes females spent significantly more time preening, orienting to, and walking and searching on clover than on geranium. However, there was no difference in time spent standing still on geranium or clover. Significance of these findings for development of effective augmentative release strategies is discussed.  相似文献   

20.
《Animal behaviour》1986,34(4):1007-1015
Welsh pony mares and foals (Equus caballus) were usually found to be within 1 or 5 m of each other during the first week of the foal's life and gradually spent more time at greater distances as the foals became older. There was an overall levelling of the trend during the 9th–15th weeks of life of the foal, followed by a second period of change during weeks 16–24. Through weeks 21–24, mares and foals spent at least half of their time within 5 m of each other. Proximity was primarily due to foal activity except during foal recumbency. During the first 8 weeks of the foal's life, a mare remained close by when it was recumbent, either by grazing in a circle around it or by standing upright beside it. Mares and foals were most likely to be close together when they were resting upright with the other ponies in the herd and most likely to be far apart when the foal was playing. Similarities in patterns of spatial relationship between the foals of a given mare were demonstrated. There was no difference between colts and filies in the development of independence.  相似文献   

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