概要

一般的に、動物の栄養状態や健康状態を評価する際には、ボディーコンディショニングスコア（BCS）による評価が行われます。動物種毎に、様々な手法や評価方法が確立されていますが、人の目視で行うため、どうしても評価者間での評価差が生じてしまいます。そこで今回、動物園で飼育するキリン、オカピおよびクロサイの体型評価を、３次元レーザー計測器で実施しました。その結果、動物の体のボディーラインや体積を数値やグラフで表すことができました。３次元レーザー計測器による体型評価が、人が目視で行うBCSの評価者間の評価差の問題を解消する代替法の一つになる可能性が示唆されました。

Abnormal conditions are diagnosed based on body weight; however, zoos lack appropriate scales for megafauna. Body shape evaluation is often used to evaluate the nutritional status of breeding animals; however, this is inaccurate for zoo animals because of inter-observer variability, especially in megafauna. Previously, three-dimensional laser measurements were used to analyse body shape of reticulated giraffe, but further studies are required to examine its effectiveness in more individuals, and other species. Here, we applied this method to reticulated giraffe, okapi, and black rhinoceros individuals for which cross-sectional area, width, and height in transverse section were determined. Relative change rates of each variable in relation to measurements at the axillary region revealed changes in body shape for each individual. Further, scatter plots and corresponding fitted curves and correlation coefficients showed a correlation between body length and approximate volume. The accuracy of three-dimensional laser measurements was demonstrated in three animal species, whereby we propose its use as an alternative method to evaluate body shape in megafauna without the inter-observer variability. In addition, this handheld device may be applied for various zoos without the scale for megafauna.