Okabe Kota, Fukuizumi Hiroki, Kawamura Ayumi, Kase Chihiro, Uetake Katsuji
Kyoto City Zoo, Kyoto city, Kyoto, Japan.
School of veterinary medicine, Azabu University, Sagamihara, Kanagawa, Japan.
Zoo Biol. 2023 Jan;42(1):157-161. doi: 10.1002/zoo.21726. Epub 2022 Aug 12.
Browsing enrichment may aid in developing species-specific behaviors for giraffes managed in zoos as a means of improving animal welfare. By nature, giraffes are tree-feeding animals, including tree bark, but the extent of food other than leaves as a form of browsing enrichment has not been well investigated. Therefore, to investigate the effectiveness of non-leaf foraging, three giraffes at the Kyoto City Zoo in Japan were observed for 228 h from May 2019 to February 2020. In conjunction with behavioral instantaneous sampling, tree use (landscape tree or enrichment branch) and plant part (leaves, twigs, or barks) were recorded by the 1-0 sampling method. There was no significant change in the foraging behavior on the leaves of enriched branches, nor was there any significant change in the foraging behavior of the giraffes, except for one animal in the deciduous phase. No significant changes were observed in rumination or other behaviors between the two phases. Although vegetation foraging behavior significantly decreased, except for one animal, dry hay foraging behavior significantly increased in all the animals during the deciduous phase. Some individuals also showed a significant increase in the foraging behavior for non-leafy parts of the enrichment branches (twigs and bark) during the deciduous phase. This suggests that in some tree species, giraffes forage on the bark and twigs to compensate for the loss of leaves during the deciduous phase, similar to feeding on hay or hay cubes as a substitute for tree leaves.
浏览富集可能有助于为动物园中饲养的长颈鹿培养特定物种的行为，以此作为改善动物福利的一种手段。从本质上讲，长颈鹿是食树动物，包括食用树皮，但作为一种浏览富集形式，除树叶之外的食物种类尚未得到充分研究。因此，为了研究非树叶觅食的有效性，2019年5月至2020年2月期间，对日本京都市动物园的三只长颈鹿进行了228小时的观察。结合行为瞬间取样，采用1-0取样法记录树木使用情况（景观树或富集树枝）和植物部位（树叶、嫩枝或树皮）。富集树枝上树叶的觅食行为没有显著变化，长颈鹿的觅食行为也没有显著变化，除了一只处于落叶期的动物。两个阶段之间在反刍或其他行为方面未观察到显著变化。虽然除一只动物外，植被觅食行为显著减少，但在落叶期所有动物的干草觅食行为显著增加。一些个体在落叶期对富集树枝的非叶部分（嫩枝和树皮）的觅食行为也显著增加。这表明，在某些树种中，长颈鹿会食用树皮和嫩枝以弥补落叶期树叶的损失，类似于以干草或干草块作为树叶的替代品。
