Transmission patterns of wool-biting behavior in housed sheep using a social network analysis

Research Project

Project/Area Number	17K08061
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Multi-year Fund
Section	一般
Research Field	Animal production science
Research Institution	Shinshu University
Principal Investigator	TAKEDA KENICHI 信州大学, 学術研究院農学系, 准教授 (90324235)
Project Period (FY)	2017-04-01 – 2020-03-31
Project Status	Completed (Fiscal Year 2019)
Budget Amount *help	¥4,680,000 (Direct Cost: ¥3,600,000、Indirect Cost: ¥1,080,000) Fiscal Year 2019: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000) Fiscal Year 2018: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000) Fiscal Year 2017: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000)
Keywords	アニマルウェルフェア / 家畜福祉 / 異常行動 / ヒツジ / 羊毛食い / 行動 / 動物福祉 / ソーシャルネットワーク分析 / 畜産学 / 動物管理・福祉 / 動物行動学
Outline of Final Research Achievements	Wool-eating, which is one of the abnormal behaviors of sheep, is a behavior in which the sheep bite the wool of themselves or other individuals and swallow it, which is a health problem. In this study, we extracted the hub individuals by social network analysis and examined the increase and decrease in the frequency of wool-biting in the flock by removing the hub individuals. We also investigated the behavioral and physiological characteristics of wool-biters. As a result, with the removal of the first and second hub individuals, the frequency of wool-biting in the whole group was significantly reduced compared to before removal (P<0.01). No correlation was found between the frequency of wool biting, social ranking, and proximity relationship in the flock. Compared with lying rest, the mean heart rate and LF/HF values were higher in lying rest when the wool eater was received and did not escape.
Academic Significance and Societal Importance of the Research Achievements	国際標準化機構（ISO）において、アニマルウェルフェアに関する一般要求事項が28年12月に発行される予定であり、ヒツジにおいてもアニマルウェルフェア基準に準拠した飼育方式が求められる。集約的管理にならざるを得ない我が国の家畜飼養形態を鑑みたとき、異常行動の発現は避けられず、その制御は必須である。本申請課題は、アニマルウェルフェアに配慮したヒツジの飼養管理方式の提案にもつながっており、国際基準に合致した食材提供が求められる国際的イベント時でのラム肉等の提供にも、成果寄与できると考えている。