草食動物の腸内細菌に関する論文がJournal of Zoo and Wildlife Medicineに掲載されました！

札幌市円山動物園基本方針「ビジョン2050」では、動物に対する科学的な視点に基づく調査や野生動物種の生理・生態の研究は欠かせない取組であり、大学などの研究機関や民間団体と協力して、動物に関する様々な調査・研究に取り組むこととしています。

このたび、草食動物の腸内細菌に関する論文が、アメリカの動物園動物医学雑誌であるJournal of Zoo and Wildlife Medicineに掲載されましたので、ご報告します。

＜今回の論文掲載及び投稿のポイント＞

・円山動物園で飼育する8種の草食動物の腸内細菌叢を解析した。
・動物の系統、消化器の構造、生態ごとに細菌叢がグループ分けされることが分かった。
・疾患を持つ動物では、健康な動物と比較して腸内細菌の多様性が低下することが分かった。
・将来的に、糞便採取という負担の少ない検査が動物園動物の疾患の早期発見につながる可能性がある。

論文概要

A CROSS-SECTIONAL SURVEY OF THE GUT MICROBIOME IN ZOO-HOUSED HERBIVORES: ASSOCIATIONS BETWEEN TAXONOMIC DEVIATIONS AND INDIVIDUAL HEALTH STATUS

※日本語訳：動物園で飼育された草食動物の腸内細菌の横断的調査：菌叢構成の逸脱と個体の健康状態の関連性

Keita Kakisaka¹⁾, Yurie Taya^{2, 5)}, Naoki Hayashi^{2, 3)}, Mohamed Abdallah Mohamed Moustafa^{2, 6)}, Mackenzie L. Kwak²⁾ , Nariaki Nonaka^{2, 3, 4)}, and Ryo Nakao^{2, 3, 4)}

1) Sapporo Maruyama Zoo, 3-1, Miyagaoka, Chuo-ku, Sapporo, 064-0959, Japan
2) Laboratory of Parasitology, Graduate School of Infectious Diseases, Faculty of Veterinary Medicine, Hokkaido University, Kita 18 Nishi 9, Kita-ku, Sapporo, Hokkaido, 060-0818, Japan
3) Division of Parasitology, Veterinary Research Unit, International Institute for Zoonosis Control, Hokkaido University, Kita-18, Nishi-9, Kita-ku, Sapporo, Hokkaido, 060-0818, Japan
4) One Health Research Center, Hokkaido University, Kita-18, Nishi-9, Kita-ku, Sapporo, Hokkaido, 060-0818, Japan
5) Division of Risk Analysis and Management, International Institute for Zoonosis Control, Hokkaido University, Kita-20, West-10, Kita-ku, Sapporo, Hokkaido, 001-0020, Japan
6) Department of Diagnostic Medicine and Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66503 USA.

Abstract

The health management of zoo-housed animals is important. Although clinical examinations are essential for health monitoring of the animals, many of them exhibit non-cooperative behavior during examinations. It is therefore necessary to develop non-invasive health monitoring tools. Gut microbiome analysis represents a novel approach to understanding the relationship between gut microbial flora and various diseases. However, the lack of information on the normal gut microbiome of zoo animals hinders the application of microbiome analysis for health management in animals. Therefore, this study aims to obtain an insight on the gut microbiomes of eight different zoo-housed herbivorous animal species, including nine eastern grey kangaroos (Macropus giganteus), four Asian elephants (Elephas maximus), one eland (Taurotragus oryx), two plains zebras (Equus quagga), two hippopotamuses (Hippopotamus amphibius), four sika deer (Cervus nippon), five sheep (Ovis aries), and two giraffes (Giraffa camelopardalis). The bacterial composition in the fecal samples was determined using 16S rRNA gene-based amplicon sequencing. The results indicated that the two hindgut fermenters (elephants and zebras) had a significantly different gut microbiome composition from that of the foregut fermenters (kangaroo, eland, deer, sheep, and giraffe). In general, individuals of the same animal species were likely to have similar microbial communities. However, a few individuals demonstrated a distinct gut microbiome, with remarkably lower alpha diversity than others in the same species. Subsequently, it was revealed that these individuals had underlying disorders, including systematic lymphoma, chronic emaciation, and rumen hypoplasia. This study is a first step towards understanding the role of the microbiome in animal health, and future studies will facilitate the application of microbiome analysis in animal health management in zoos.

掲載誌

Journal of Zoo and Wildlife Medicine, 57(3):647-657 (2026).