@article{oai:spua.repo.nii.ac.jp:00000029,
 author = {瀬戸, 隆弘 and SETO, Takahiro and 鳥羽, 雄一 and TOBA, Yuichi},
 issue = {3},
 journal = {家畜診療, Journal of livestock medicine},
 month = {Mar},
 note = {application/pdf, 暑熱，乳量および反芻時間の関連性調査と共に，反芻から暑熱耐性が弱い牛（暑熱感受性牛）を推測できるか検証した。その結果，温湿度係数（THI）の増加に伴い，平均乳量とほぼ並行して平均反芻時間が減少していた。また，暑熱時は反芻時間の分散が増加し，分布も１峰性から２峰性に遷移した。さらに，暑熱期直前の平均反芻時間を基に暑熱感受性牛と耐性牛を推定したところ，感受性牛は暑熱期の反芻時間および反芻変化量（405.7±51.7分/日および－25.0±47.6分/日）が耐性牛（537.1±43.5分/日及び－11.7±39.6分/日）より低値を示した（p＜0.01）。以上から，反芻時間から牛個体の暑熱ストレスが判定でき，暑熱期前に暑熱感受性牛を予測できる可能性が示唆された。, The correlation was investigated among heat stress, milk yield, and ruminating time to verify whether the presence of heat-sensitive cows can be predicted based on the ruminating condition. The results showed that the mean milk yield and mean ruminating time decreased as the temperature humidity index (THI) increased. For the ruminating time, the variance increased, and the distribution changed into bimodal one from unimodal one in the heat period. When cows were assumed to be heat-sensitive or heat-resistant based on the mean ruminating time immediately before the heat period, the ruminating time and its reduction were shorter and larger respectively in the heatsensitive cows (405.7 ± 51.7 minutes/day and –25.0 ± 47.6 minutes/day respectively) compared to the heat-resistant cows (537.1 ± 43.5 minutes/day and –11.7 ± 39.6 minutes/day respectively, p < 0.01). These findings suggested that the ruminating time can determine the heat stress of individual cows and that the presence of heat-sensitive cows can be predicted before the heat period.},
 pages = {151--158},
 title = {ホルスタイン種乳牛における暑熱と反芻時間，乳量との関連性および反芻時間を用いた暑熱感受性牛早期発見法},
 volume = {69},
 year = {2022},
 yomi = {セト, タカヒロ and トバ, ユウイチ}
}