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The onset in spring and the end in autumn of the thermal and vegetative growing season affect calving time and reproductive success in reindeer

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Current Zoology 2020年第2期66卷 123-134页

作者： Amelie Paoli Robert B.Weladji фystein holand Jouko Kumpula Department of Biology Concordia University7141 Sherbrooke Street WestMontrealQCH4B 1R6Canada Department of Animal and Aquacultural Sciences Norwegian University of Life SciencesAsPO Box 5003Norway Natural Resources Institute of Finland(Luke) Reindeer Research Station99910Finland

A developing trophic mismatch between the peak of energy demands by reproducing animals and the peak of forage availability has caused many species'reproductive success to *** match-mismatch hypothesis(MMH)is an appealing concept that can be used to assess such fitness ***,concerns have been raised on applying the MMH on capital breeders such as reindeer because the reliance on maternal capita rather than dietary income may mitigate negative effects of changing *** a long-term dataset of reindeer calving dates recorded since 1970 in a semidomesticated reindeer population in Finnish Lapland and proxies of plant phenology;we tested the main hypothesis that the time lag between calving date and the plant phenology in autumn when females store nutrient reserves to finance reproduction would lead to consequences on reproductive success,as the time lag with spring conditions *** predicted,the reproductive success of females of the Kutuharju reindeer population was affected by both the onset of spring green-up and vegetative senescence in autumn as calves were born heavier and with a higher first-summer survival when the onset of the vegetation growth was earlier and the end of the thermal growing season the previous year was earlier as *** results demonstrated that longer plant growing seasons might be detrimental to reindeer's reproductive success if a later end is accompanied by a reduced abundance of mushrooms.

关键词： lagged effect match-mismatch hypothesis plant phenology Rangiter tarandus time lag ungulates

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Flexible mating tactics and associated reproductive effort during the rutting season in male reindeer （Rangifer tarandus, L. 1758）

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Current Zoology 2015年第5期61卷 802-810页

作者： Eliana PINTUS Stefania UCCHEDDU Knut H. RФED Javier Perez GONZALEZ Juan CARRANZA Mauri NIEMINEN фystein holand Department of Veterinary Sciences Faculty of Agrobiology Food and Natural Resources Czech University of Life Sciences Kamycka 129 165 21 Prague 6 - Suchdol Czech Republic Ungulate Research Unit Game and Fish Research Center University of Cordoba 14071 Cordoba Spain Department of Basic Sciences and Aquatic Medicine Norwegian University of Life Sciences EO. Box 8146 Dep. N-0033 Oslo Norway Guarderia Rural Mancomunidad de Municipios Centro (MIMC) 06810 Calamonte Spain Finnish Game and Fisheries Research Institute Reindeer Research Station 99910 Kaamanen Finland Department of Animal and Aquacultural Sciences Norwegian University of Life Sciences RO. Box 5003 N-1432 As Norway

Polygynous males can change their mating tactics across their lifetime, but information is scarce on the flexibility of this trait within a given season and the relative costs and benefits of using different tactics. Here, we monitored individually marked male reindeerRangifer tarandusand classified their mating tactics as harem-defense, sneaking, or mixed. The costs of the male reproductive effort were assessed using both direct (i.e. percentage of body mass lost) and indirect measures (i.e. activity patterns such as feeding, standing, and walking), while mating group size and reproductive success were recorded as mating effort benefits. Our results show that reindeer males may switch between the harem-defense and sneaking tactics throughout the same breeding season, providing further support to the notion that reproductive tactics are flexible in ungulates. The costs and benefits of male mating effort vary according to the mating tactic, reaching the highest values in harem-holders and the lowest values in sneaking males. Moreover, males who switched between the sneaking tactic and the harem-defence tactic tended to achieve higher mating success than males who consistently used the least costly tactic. Indeed, all harem-holders successfully sired offspring, whereas only two out of three mixed-tactic males sired one calf, and sneaking males did not sire any calves. In conclusion, our results show that reindeer males can modulate their mating efforts during the same breeding season by switching between the most costly harem-defense tactic and the least costly sneaking tactic, suggesting individual solutions to the balance between reproductive effort and mating opportunities.

关键词：繁殖成功率交配策略繁殖季节驯鹿雄性男性生殖成本效益混合策略

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森林再生的时间尺度:挪威南部被抛弃的放牧场与农田

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人类环境杂志 1998年第6期27卷 456-460页

作者： Hans Staaland φystein holand Christian Nellemann Martin Smith 闵庆文挪威农业大学生物学与自然保护系挪威农业大学生物与自然保护系阿拉斯加大学

本文目的在于说明被抛弃的农田与牧场转变成天然森林的速度。研究是在挪威南部鲁默里克景观保护区(The Romerike LandscapeProtection Area)进行的,该地区呈南部北方森林植被区的深谷景观,进行农业与放牧畜牧业生产已有数百年历史。当5... 详细信息

本文目的在于说明被抛弃的农田与牧场转变成天然森林的速度。研究是在挪威南部鲁默里克景观保护区(The Romerike LandscapeProtection Area)进行的,该地区呈南部北方森林植被区的深谷景观,进行农业与放牧畜牧业生产已有数百年历史。当50年代引入农业机械化和生产专业化时,这一地区的农田被逐渐抛弃,闲置而再生为森林生态系统。以前用于放牧的旷野地区减少近50%,灌丛和森林(主要是灰桤木)的面积增加。再生演替的速度取决于距林缘距离和在深谷底部潮湿土地的植被类型,它要比干旱地区的植被再生速度慢。土地利用变化的结果是使群落多样性减少和森林与旷野地区等之间的生态交错带长度缩短。从长期来看,森林的再生可能会减少动植物的多样性。

关键词：森林再生时间尺度挪威废弃放牧场废弃农田

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Mismatch between calf paternity and observed copulations between male and female reindeer:Multiple mating in a polygynous ungulate?

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Current Zoology 2023年第4期69卷 377-384页

作者： Keenin R.Coombs Robert B.Weladji Ostein holand Knut H.Rodc Department of Biology Concordia University7141 Sherbrooke St.WestMontrealQCH4B1R6Canada Department of Animal and Aquacultural Sciences Norwegian University of Life SciencesOluf Thesens vei 61433ÅsNorway Faculty of Veterinary Medicine Norwegian University of Life SciencesVeterinærbygningenElizabeth Stephansens vei 15N-1430ÅsNorway

In polygynous systems,such as that exhibited by reindeer Rangifer tarandus,mate choice can be difficult to disentangle from male intrasexual competition because male behavior may constrain female *** mating may provide an avenue for female mate choice,though it is difficult to identify using behavioral estimators *** techniques address this issue by affording ecologists an opportunity to reassess mating systems from a genetic *** assessed the frequency and possible explanations for multiple mating in reindeer using a genetic approach to determine the success of observed copulations in a semi-domesticated herd in Kaamanen,*** and genetic data were synthesized with population characteristics over a 7-year period to test the hypothesis that,if present,polyandry in reindeer is driven by sexual harassment from sub-dominant *** observed multiple mating in 42%of females,with as many as 60%exhibiting multiple mating in certain *** found no evidence that multiple mating resulted from sexual harassment by sub-dominant males,suggesting that it is likely a deliberate strategy among *** rate of copulations into paternities varied with male size,with smaller males more likely to experience mismatch than larger *** preference for larger males persisted despite the occurrence of multiple mating,possibly suggesting a mechanism for cryptic post-copulatory *** suggest further research to delineate the possible influence of cryptic post-copulatory selection and multiple mating to defend against infertility in exhausted males.

关键词： female choice mate choice mating systems polyandry reproductive success sexual selection

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有限单元法在应力分析中的应用

有限单元法在应力分析中的应用

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作者： I.·霍拉德(I. holand) K.·贝尔(K. Bell)

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Family history and disease outcomes in patients with Crohn's disease:A comparison between China and the United States

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World Journal of Gastrointestinal Pharmacology and Therapeutics 2016年第4期7卷 556-563页

作者： Pei-Qi Wang Jun Hu Elie S Al Kazzi Eboselume Akhuemonkhan Min Zhi Xiang Gao Raquel holand de Paula Pessoa Sami Ghazaleh Tuhina Cornelius Suhel Abbas Sabunwala Shadi Ghadermarzi Kartikeya Tripathi Mark Lazarev Pin-Jin Hu Susan Hutfless Department of Medicine Division of Gastroenterology and HepatologyJohns Hopkins University Guangdong provincial Key Laboratory of Colorectal and Pelvic Floor Diseases the Sixth Affiliated Hospital of Sun Yat-sen University Department of Gastroenterology the Sixth Affiliated Hospital of Sun Yat-sen University Department of Medicine Med Star Health Internal Medicine Department of Health and Sport Sciences Federal University of Acre Department of Medicine Faculty of Medicine and Health SciencesAn-Najah National University Ravindra Nath Tagore Medical College St Vincent Hospital Department of Epidemiology Johns Hopkins University Bloomberg School of Public Health

AIM To investigate the differences in family history of inflammatory bowel disease(IBD) and clinical outcomes among individuals with Crohn's disease(CD) residing in China and the United *** We performed a survey-based cross-sectional study of participants with CD recruited from China and the United *** compared the prevalence of IBD family history and history of ileal involvement,CD-related surgeries and IBD medications in China and the United States,adjusting for potential *** We recruited 49 participants from China and 145 from the United *** prevalence of family history of IBD was significantly lower in China compared with the United States(China:4.1%,United States:39.3%).The three most commonly affected types of relatives were cousin,sibling,and parent in the United States compared with child and sibling in *** involvement(China:63.3%,United States:63.5%) and surgery for CD(China:51.0%,United States:49.7%) were nearly equivalent in the two *** The lower prevalence of familial clustering of IBD in China may suggest that the etiology of CD is less attributed to genetic background or a family-shared environment compared with the United *** the potential difference in etiology,surgery and ileal involvement were similar in the two *** the changes in family history during the continuing rise in IBD may provide further insight into the etiology of CD.

关键词： Crohn’s disease Family history Disease outcome Inflammatory bowel disease Epidemiology genetics Environment Medication Surgery

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