歩行運動および採食負荷条件下における育成牛の熱産生量と心拍数との関係 Relationship between Heart Rate and Heat Production of Holstein Heifers During Eating and Walking
The relationship between heart rate and heat production of Holstein heifers was studied in two conditions. One was during exercise walking, and the other was during food intake. Five Holstein heifers were used in the study. In the walking exercise, heifers were walked on a treadmill at speeds of 6.7, 11.5, 16.7, 23.0, 30.0, and 40.0m/min. For increased levels of food intake, heifers were fed formula food in 500g increments until a total of 3, 000g had been consumed at intervals of 15 minutes. Heart rates were counted from E. C. G., and heat production was calculated from O2 consumption using a head chamber. All regression equations were significant, and correlation coefficient of walking exercise was higher than that of increased levels of food intake. As a result of covariance analysis, the equations obtained from walking exercise and from increased levels of food intake were identified in two heifers. In the other three heifers, regression coefficients were identified, but regression constants were not identified. Regression coefficients were identified between walking exercise and increased levels of food intake. In this experiment however, regression constants were not identified. This was due to the method of establishing food intake. When calculating regression equations between heart rate and heat production, it is necessary to ensure that rate of food intake is the same as in the field.
- 日本畜産學會報 = The Japanese journal of zootechnical science
日本畜産學會報 = The Japanese journal of zootechnical science 69(4), 387-391, 1998-04-25
Japanese Society of Animal Science