Changes in Immunity-, Antioxidative Potential- and Metabolism-Related Blood Composition with the Transition to an Outdoor Rearing System during the Winter Season
アイテムタイプ
紀要論文 / Departmental Bulletin Paper
言語
日本語
キーワード
冬季屋外飼育, 黒毛和種繁殖雌牛, 免疫, 抗酸化能
キーワード(英)
Outdoors, Winter, Japanese Black Cows, Immunity, Antioxidative Potential
We investigated changes in the blood composition of Japanese Black cows associated with the transition to an outdoor rearing system during the winter season. Eight pregnant Japanese Black cows were divided into 2 groups. We compared blood compositions during indoor and outdoor rearing using a 2-term reversal test design. We collected blood sample at 0, 1, 4, 8, and 11 days after the test started. Immunoglobulin G, white blood cell counts, neutrophil phagocytosis, and the ratio of neutrophils to lymphocytes were measured as immunity-related factors ; degree of oxidation and antioxidative ability were measured as antioxidative potential factors ; and glucose, cholesterol, non-esterified fatty acids, total protein, and cortisol were measured as metabolism-related factors. Outdoor temperatures during the period of the test were approximately 4-8 degrees centigrade lower than those indoors. There were no significant differences between indoor- and outdoor-reared cows with respect to any of the immunity-related blood factors. The antioxidative ability of outdoor-reared cows was significantly higher than that of indoor-reared cows. In contrast, the degree of oxidation showed no significant difference between indoor and outdoor rearing. The higher antioxidative ability under outdoor conditions could be attributable to an increase in activity. Glucose, non-esterified fatty acids, and cortisol were all higher under outdoor conditions. These results indicate that cows reared under outdoor conditions have an enhanced energy metabolism to cope with the lower temperature environment.