Investigation of corticosteroid levels in the hairs of female Holstein calves.

This study was designed to investigate the degree of long-term effects by measuring cortisol and aldosterone concentrations in the growing hair including lipid which is absorbed from the blood of six female Holstein calves by enzyme-linked immunosorbent assay (ELISA). The total number of calves used was 18 (three seasons). Three comparative factors were used: region (back and chest), hair color (black and white), and season (summer, winter, and spring). The hair cortisol of the back region (white color) was higher than the other region and color (p < 0.05). The measured value in the spring season (back region) was significantly higher than that in the summer (chest region) (p < 0.05). Although there has been no report on the hair aldosterone until now, it was possible to measure the concentration in the present study. The hair aldosterone of the back region was higher than the chest region (p < 0.01), and the white hair color was higher than the black hair color (p < 0.05). The measured value in the spring season was also significantly higher than that in the summer season and the winter season (p < 0.01). This result suggested the changes are affected by the hair region factor, the hair color factor, and the changing meteorological conditions.