京都市動物園における研究成果（2019年度）研究成果・業績
2019年度の成果発表をまとめました。(2020年4月10日更新）
論文
国内外学術誌に論文を発表しました。
[NEW!] ゾウ使いがアジアゾウの社会行動に与える影響
Yasui S, Idani G. (2020) The effect of proximity relations to mahouts on social behaviours among captive Asian elephants (Elephas maximas).
Animal Behaviour and Management (動物の行動と管理学会誌) 2020年56巻1号: 1-7.
DOI: https://doi.org/10.20652/jabm.56.1_1 （外部リンク）
（要旨）
アジアゾウは，古くから使役動物としてアジアの国々で，人とともに生活してきた。また，世界中の動物園で多くのアジアゾウが飼育され，飼育員やゾウ使いとゾウとの事故は現在もしばしば起こっている。飼育下でのゾウの管理において，人とゾウの関係は非常に重要であるにもかかわらず，これまであまり研究されてこなかった。したがって，本研究の目的は，ゾウとゾウ使いとの関係が，ゾウの行動にどのように影響するかを明らかにすることとした。
タイ，スリン県にあるゾウ研究センターにいる17頭の飼育下アジアゾウを対象として研究を行った。個体追跡法を用いて，対象個体のすべての社会行動を記録し，また1分ごとにゾウとゾウ使いとの距離を記録した。ゾウの社会行動の頻度と，ゾウがゾウ使いと近接している割合を比較した結果，ゾウ使いと近接している割合が高いゾウは，他個体との社会行動の頻度が低いことがわかった。
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[NEW!] 混合展示におけるアミメキリンとグレビーシマウマの異種間関係の出産前後での比較.
小倉匡俊，近藤沙紀，中尾小百合，河村あゆみ，福泉洋樹，岡部光太 (2020)
Animal Behaviour and Management (動物の行動と管理学会誌) 2020年56巻1号: 8-17.
DOI: https://doi.org/10.20652/jabm.56.1_8 （外部リンク）
（要旨）
動物園において複数の動物種を同一空間で飼育展示する混合展示はさまざまなメリットがある。しかし動物福祉を損ないうる状況も存在し，たとえば出産と哺育に対して混合展示が負の影響を与えうることが指摘されている。本研究では日本の動物園における混合展示の代表的な組み合わせであるアミメキリン Giraffa camelopardalis reticulataとグレビーシマウマ Equus grevyi を対象に評価するとともに，グレビーシマウマの出産が動物福祉に与える影響を調べた。京都市動物園で飼育されていたアミメキリン 3個体とグレビーシマウマ 1個体（出産後は2個体）を対象に，社会行動と最近接個体，個体間距離を記録し，出産の前後で比較した。その結果，出産前後ともに異種間での親和行動が観察され，一定の良好な関係を築いていることが確認された。しかし個体の組み合わせによっては親和行動が減少し敵対行動が増加するなど，出産によるネガティブな変化も見られた。混合展示により個体数の限られた飼育環境においても社会的な刺激がもたらされることと，出産と哺育に際する攻撃行動の増加に対する注意の重要性が示された。
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[NEW!] 動物の行動と管理学会設立シンポジウム報告－新学会への期待と今後の方向性.
友永雅樹，矢用健一，森田茂，田中正之，加隈良枝，江口祐輔，池口厚男 (2020)
Animal Behaviour and Management (動物の行動と管理学会誌) 2020年56巻1号: 34-44.
DOI: https://doi.org/10.20652/jabm.56.1_34 （外部リンク）
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[NEW!]キリンへの冬季の樹木給餌は口の常同行動を減少させるか？
岡部 光太, 河村 あゆみ, 福泉 洋樹, 石内 琴音, 加瀬 ちひろ
Animal Behaviour and Management (動物の行動と管理学会誌) 2019年55巻4号 p.165-173
https://doi.org/10.20652/jabm.55.4_165
（要旨）
近年、動物福祉の観点から飼育動物の環境の改善が多くの動物園で行われている。特にキリンでは、口の常同行動の減少のために複数の採食エンリッチメントの実施が行われている。先行研究では、複数の給餌器の設置や乾草の給餌量の変更、樹木給餌の実施が常同行動の減少に効果があったとされている。しかし、樹木給餌は冬季の実施が困難であり、冬季においてはその効果も明らかとはなっていなかった。そこで今回、全ての季節において樹木給餌を行い、樹木摂食量と口の常同行動の調査を行った。観察には京都市動物園で飼育する3頭のキリンを供試した。その結果、樹木摂食量は季節間で有意な変化は見られず、ほぼ同量の摂食が確認された。一方、全ての個体で口の常同行動が観察され、有意に冬に増加する結果となった。樹木摂食量と口の常同行動の発現量には相関は見られなかった。そのため、今回の観察において、樹木摂餌量ではない、例えば本来の生息地との間に生まれる気候的なギャップが要因となっている可能性が考えられた。それゆえ、口の常同行動に与えるその諸要因は未だは明らかではないため、今後さらなる研究が必要である。
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飼育キリンにおける夜間の授乳行動
Saito, M., Takagi, N., Tanaka, M., & Yamanashi, Y. (2020). Nighttime Suckling Behavior in Captive Giraffe (Giraffa camelopardalis reticulata). Zoological Science, 37(1), 1-6, 6.
https://doi.org/10.2108/zs190094
（要旨）
9614時間に及ぶビデオデータを解析して，キリンの離乳が平均で448日間で起きることや夜間授乳行動が昼間と変わらない期間起きるものの，時間は短いことなどをあきらかにしました。また，こどもが生まれた直後1週間を除き母親が授乳の開始や終了タイミングを決めていることもあきらかになりました。
（英文要旨）
Suckling behaviors are useful to better understand mother–offspring relationships. However, in many species, knowledge about nighttime suckling behavior is sparse. In the present study, we investigated suckling behavior in four calves of the reticulated giraffe (Giraffa camelopardalis reticulata) and their mother in the Kyoto City Zoo, Japan, by analyzing video clips of 9614 h. The relation between a calf’s age and the mean duration and frequency of suckling were consistent with the results of previous daytime studies: the longest duration (80 ± 4 s) and highest frequency (0.41/h) of suckling occurred when the calves were young, and decreased thereafter. Suckling frequency was lower at night than during the day, probably because the mother spent much of the time resting at night. The mother initiated suckling behavior in offspring until six months of age. Most often, the mother terminated suckling except during the first few weeks after birth. Additionally, we reported that the average weaning period was 448 days (n = 5) and that the last born (sixth) continued to suckle for more than 750 days, which is a rare phenomenon. We believe the present report helps to fill the lack of knowledge about nighttime suckling behavior in giraffe.
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飼育下トラにおける環境エンリッチメントの有効性及び来園者による影響の検証
岡 桃子，山梨 裕美，岡部 光太，松永 雅之，平田 聡, (2019),
動物の行動と管理学会誌, 55 巻, 3 号:, 107-116.
公開日 2019/11/01, https://doi.org/10.20652/jabm.55.3_107
飼育下の大型ネコ科動物で問題とされている常同歩行の発現には環境エンリッチメント（以下エンリッチメント）の有無や来園者の影響など複数の要因が絡んでいると考えられるが、複合的な検討は行われていない。そこで本研究ではエンリッチメントの有効性及び来園者数と気温がトラの行動に与える影響について検証した。京都市動物園で飼育されているアムールトラ3 頭を対象とし、 3 分毎の瞬間サンプリングを用いて行動を記録した。放飼場内に設置するエンリッチメントの種類が多いと、トラの常同歩行頻度は有意に減少し（P < 0.05）、エンリッチメントの利用頻度が有意に増加した（P < 0.01）。複数のエンリッチメントの設置はトラの常同歩行の抑制に効果的であり、探索行動や捕食行動等多様な行動を引き出す上で有用であることが示唆された。また来園者の存在によって、トラの休息頻度が増加、エンリッチメントの利用頻度が低下する可能性があると考えられた。
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「動物園のキリンにおける睡眠関連行動：基本的な特徴と季節と出産による影響」
Takagi, N, Saito, M, Ito, H, Tanaka, M, Yamanashi, Y. Sleep‐related behaviors in zoo‐housed giraffes (Giraffa camelopardalis reticulata): Basic characteristics and effects of season and parturition. Zoo Biology.2019; 38: 490– 497. https://doi.org/10.1002/zoo.21511
2019年8月8日公開
（英文要旨）
Despite increasing interest in the behavior of zoo animals, studies of nocturnal behavior of zoo animals are limited. In this study, we investigated the relationship between parturition, season, and the sleep‐related behaviors in captive reticulated giraffes to better understand the nocturnal life in giraffes. The subjects were two adult reticulated giraffes living in Kyoto City Zoo, Japan. Observations were made via an infrared camera that was mounted in the indoor enclosure between June 2007 and August 2009. We analyzed video clips that were recorded between 16:30 and 09:00 the next morning, over a total of 199 days. Sleep‐related behaviors were classified into two categories based on the posture of the giraffes; recumbent posture and paradoxical sleep. We also recorded the laterality of recumbent posture, which was coded based on the direction of the legs against the torso (right or left). Seasonal differences in sleep behaviors between summer and winter were observed in both individuals. They tended to start to lie down earlier in the winter than in the summer. Parturition also affected the behaviors as both individuals decreased the behaviors before and after the parturition of the female. Additionally, the female lay on her left side less frequently than her right when resuming a recumbent posture in the pre‐parturition period, while such laterality was not observed in the baseline and post‐parturition period. These results suggested that season and parturition are important factors for determining the sleep‐related behaviors in giraffes. Further studies are needed to understand how these changes in sleep affect other welfare parameters.
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山梨 裕美・櫻庭 陽子 (2019) 大型類人猿の社会性に配慮した飼育管理:実践と研究の視点から. 動物心理学研究 (早期公開) https://www.jstage.jst.go.jp/article/janip/advpub/0/advpub_69.1.8
（英文要旨）
With the accumulation of knowledge regarding sociality of animals, social enrichment is regarded as one of the most important part of captive animal care. Although the basic knowledge has been accumulated, sociality involves complex issues. Moreover, practical methodologies for social management remain controversial. In this paper, we overview the current studies and practices of social management on four great ape species (chimpanzees, western lowland gorillas, and Bornean and Sumatran orangutans) housed in Japanese zoos to advance the sociality discussion. We first describe the fundamentals of sociality in animals. Then we explore important topics of sociality, including social relationships in captivity, all male group formation in chimpanzees and gorillas, group living in orangutans, and welfare of disabled and geriatric individuals. Although the number of sociality studies has recently increased, to maximize the positive effects of captive social living, more detailed understanding of the effects of social factors on animals using scientific methodologies is important.
（2019年7月18日公開）
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「ツシマヤマネコの遺伝的多様性は，大陸のアムールヤマネコと比較して，極端に低いことが示された：保全への示唆として。」
Hideyuki Ito and Miho Inoue-Murayama. 2019. The Tsushima leopard cat exhibits extremely low genetic diversity compared with the Korean Amur leopard cat: Implications for conservation. PeerJ, 7297. https://peerj.com/articles/7297.pdf
（英文要旨）
We examined genetic diversity of the wild Tsushima leopard cata regional population of the Amur leopard catusing microsatellite markers. In addition, we compared genetic diversity of the Tsushima leopard cat with that of the Korean population of Amur leopard cat. Although bias should be considered when applying cross-species amplification, the Tsushima leopard cat showed a lower index of molecular genetic diversity than did the Korean population. These results were consistent with those obtained using other genetic markers, such as mitochondrial DNA and Y chromosome sequences. This low genetic diversity of the wild Tsushima leopard cat may be derived from the founding population. Furthermore, our results suggest that the captive populations held in Japanese zoos may show extremely low genetic diversity, leading to difficulties in genetic management of the Tsushima leopard cat. Moreover, the two regional populations were clearly separated using these marker sets. In the present study, we demonstrated that the genetic diversity of the Tsushima leopard cat is extremely low compared with that of the continental regional population. Importantly, the Japanese captive population for ex situ conservation was derived from a founding population with extremely low genetic diversity; hence, we assume that both the captive and wild populations showed extremely low genetic diversities. Our findings emphasize the need to develop carefully considered management strategies for genetic conservation.
（2019年7月15日公開）
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山梨 裕美, (2019) チンパンジーの社会関係と長期的なストレス：研究領域としての動物福祉., 霊長類研究, 35: 23-32. https://doi.org/10.2354/psj.35.006
(英文要旨）
Both general and academic attention toward animal welfare has been increasing and the importance of scientific investigation into welfare states of captive animals is being recognized. One of the big questions in scientific studies of animal welfare is how we can assess animal welfare in an objective manner, and this is an intensively debated topic. In this paper, I reviewed the studies on captive chimpanzees (Pan troglodytes) in order to discuss the methodologies used to assess welfare states and introduce studies that have investigated how social environments affect chimpanzee welfare by combining behavioral and hair cortisol (HC) measurements. Recently, cortisol accumulated in the hair of animals has been considered as an indicator of the long-term hypothalamus-pituitary-adrenal (HPA) axis. From a welfare perspective, long-term stress is more problematic than acute stress as it is challenging for animals to experience distress over a long period and long-term activation of the HPA axis can result in overall health deterioration. A series of studies on captive chimpanzees show that HC is useful for monitoring the long-term stress levels in captive chimpanzees. Furthermore, using the novel measure of long-term stress, I found that the stress level of male chimpanzees is affected by social variables and that male chimpanzees use social play as a means to reduce social tension. Although scientific investigation of animal welfare is still not a prevalent practice in Japan, it is a promising area of study both for improving animal welfare and deepening our understanding about animals.
（2019年7月12日公開）
国際会議等での発表
2019.06.22～26 国際エンリッチメント会議を京都大学および京都市動物園で開催しました！詳しくはHPへ。
1. Kyoko Kuroda, Hiroki Yoneda, Mitsunori Nagao, Kanae Shimada, Yusuke Aramaki, Ryota Seo, Yoko Sakuraba, Yumi Yamanashi, Masayuki Tanaka (2019) Introduction of New Elephants to a Former Solitary Captive Elephant: The Process of Forming Social Relationships. The 14th International Conference on Environmental Enrichment (June 22-26, Kyoto, Japan).
2. Shigeru Ninomiya Nana Kojima, Kie Higashi, Miyu Fujimura, Yumi Yamanashi, Ayumi Kawamura3, Hiroki Fukuizumi (2018) Environmental Enrichment for Self-Grooming in Farm and Zoo Animals. The 14th International Conference on Environmental Enrichment (June 22-26, Kyoto, Japan).
3. Mitsunori Nagao (2019) Ex-Situ Conservation of the Tsushima Leopard Cat by the Cooperation with JAZA and MOE. The 14th International Conference on Environmental Enrichment (June 22-26, Kyoto, Japan).
4. Kota Okabe, Masayuki Matsunaga, Ryuichiro Kado, Sachiko Seko, Kazuhiko Nakano, Kaname Okahashi, Katsuji Uetake (2019) Use of Cardboard Boxes as Environmental Enrichment for Captive Tigers (Panthera tigris altaica). The 14th International Conference on Environmental Enrichment (June 22-26, Kyoto, Japan).
5. Saki Yasui, Fumiko Nakahara, Naoko Takagi (2019) Environmental Enrichment and Birth Support for Western Gorillas at the Kyoto City Zoo. The 14th International Conference on Environmental Enrichment (June 22-26, Kyoto, Japan).
6. Yumi Yamanashi, Yoko Sakuraba, Fumio Itoh, Yasunori Takenaka, Ryuichiro Kado (2019) Filling the Gap: Animal Welfare Risk Assessment and Its Application to Enhance the Quality of Life of Zoo Animals. The 14th International Conference on Environmental Enrichment (June 22-26, Kyoto, Japan).
7. Nobuhiro Yamada, Hideko Takeshita, Junichi Takashio, Yoko Sakuraba, Ichiro Takahashi, Fumito Kawakami, Misato Hayashi, Masaki Tomonaga (2019) Developmental Support of Chimpanzee with Cerebral Palsy. The 14th International Conference on Environmental Enrichment (June 22-26, Kyoto, Japan).
8. Masato Yayota, Yukari Kashima1, Yuma Tsuchiya, Yusuke Aramaki, Ryuichiro Kado, Hideyuki Ito (2019) Feeding Enrichment Using an Automatic Feeder for Captive Asian Elephants (Elephas maximus). The 14th International Conference on Environmental Enrichment (June 22-26, Kyoto, Japan).
9. Shiori Mitsuya, Saika Yamazaki, Tadatoshi Ogura, Shintaro Hagiwara, Naoko Suda-Hashimoto, Kota Okabe, Yu Nakayama, Shinichi Kioka, Kazuyuki Ban, Yudai Arai, Yuki Ishida, Yumi Yamanashi, Yuki Taguchi, Nao Koyama (2019) Introduction of Activities by SHAPE-Japan. The 14th International Conference on Environmental Enrichment (June 22-26, Kyoto, Japan).
10. Yusuke Aramaki, Nobuaki Iwahasi, Saki Yasui (2019) Effects of Three Types of Environmental Enrichment on the Behaviors of Captive Brazilian Tapirs. The 14th International Conference on Environmental Enrichment (June 22-26, Kyoto, Japan).
11. Masayuki Tanaka, Yoko Sakuraba (2019) Ten Years of Long-lasting Cognitive Enrichment for Zoo Primates: Cultural Transmission in Kyoto City Zoo. The 14th International Conference on Environmental Enrichment (June 22-26, Kyoto, Japan).
12. Yoko Sakuraba, Nobuhiro Yamada, Ichiro Takahashi, Fumito Kawakami, Jun’ichi Takashio, Hideko Takeshita, Misato Hayashi, Masaki Tomonaga (2019) Evaluating of Physical State on a Female Chimpanzee with Cerebral Palsy: A Case Study. The 14th International Conference on Environmental Enrichment (June 22-26, Kyoto, Japan).
13. Haruna Bando, Yumi Yamanashi, Naoko Takagi, Yoko Sakuraba (2019) Environmental Enrichment Projects for Geriatric Rhesus Macaques with Zoo Visitors. The 14th International Conference on Environmental Enrichment (June 22-26, Kyoto, Japan).
14. Kanae Shimada, Aoi Takahashi, Fumiko Nakahara, Yumi Yamanashi (2019) Assessing the Effect of Visitor Contact on Stress Levels in Guinea Pigs by Measuring Salivary Cortisol Levels. The 14th International Conference on Environmental Enrichment (June 22-26, Kyoto, Japan).
15. Kei Nemoto, Yumi Yamanashi, Koshiro Watanuki, Akinori Dosyo, Josue Alejanro Pastrana
(2019) Improving Living Environment of Lesser Slow Loris. The 14th International Conference on Environmental Enrichment (June 22-26, Kyoto, Japan).
16. Fumihiro Kano, Yutaro Sato, Yumi Yamanashi (2019) The KYOTO STEAM – International Arts × Science Festival project: Art × Science IN Kyoto City Zoo What do chimpanzees feel in arts? The 14th International Conference on Environmental Enrichment (June 22-26, Kyoto, Japan).
17. Yuko Ikkatai, André Gonçalves, Josue Alejandro Pastrana, Yumi Yamanashi (2019) Ask Participants: Perception of Animal Death. The 14th International Conference on Environmental Enrichment (June 22-26, Kyoto, Japan).
国内学会等での発表
田中正之・櫻庭陽子・吉田信明 (2019) 京都市動物園チンパンジー認知エンリッチメント１０年間の記録. 第35回日本霊長類学会大会（7月12－14日，熊本市）
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