| Summary: | 碩士 === 國立中興大學 === 獸醫學系暨研究所 === 97 === The corticosterone is secreted from adrenal and controlled by hypothalamic- pituitary-adrenal axis (HPA axis) in respond to environmental stressor and emotional arousal. Therefore, it was called the “stress hormones”. The measurement of fecal corticosterone was a non-invsive technique and become a demonstration tool for assessing environmental stress or other pressure in wild animals. In this study, fourteen collared- scope owls (body size 23-25 cm, body weight 164-188 g), which caged all-together for more than six months, were separated into different cages. The fecal samples were collected randomly before transfer and in the 1st, 2nd, 3rd, 4th, 6th, 8th, 10th, 14th, 17th, and 21th days after owls’ separation. Fecal corticosterone concentration was measured by EIA. The results showed that an acute rise in fecal corticosterone concentration appeared on the four days after separation. The concentration of corticosterone, however, decreased gradually to baseline level, the mean concentration before transfer, in the period on 8th day, the fecal corticosterone concentration of some individuals were lower than to baseline levels. Three phases were defined according to the fecal corticosterone concentration. Phase Ⅰ: From the 1st to the 4th day after separation, a peak of corticosterone concentration in feces indicates a stress effect of handing, examine, and change of environment in this phase. PhaseⅡ: From the 4th to the 8th day after separation, after the fecal corticosterone concentration decreased gradually to a baseline level indicates the stress effect diminished in this phase. PhaseⅢ: From the 8th to the 21th day after separation, the mean concentration of fecal corticosterone maintained in only 1/3 of baseline levels. We suggested that a feedback effect of HPA axis resulted in the fecal corticosterone concentration. The collared-scope owls needed 8 to 10 days to adapt to a new environment. Our results showed that the noninvasive method by assessing fecal corticosterone concentration was a suitable technique to evaluate the stress effect of transfer in collared-scope owls.
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