| Abstract: | We studied androgen production during development in nestling Eastern Screech-Owls (Megascops asio) and hypothesized that gender and hatch order might influence serum levels of testosterone and androstenedione. Testosterone levels were highest immediately after hatching and declined significantly in the 4 weeks leading to fledging. The average level of testosterone for 1-7 day-old owls was 3.99 - 0.68 ng/ml. At 22-28 days of age, the average testosterone level for nestling owls was 0.83 - 0.18 ng/ml. Testosterone levels did not differ between males or females. The average testosterone level for male nestlings was 2.23 - 0.29 ng/ml and 2.39 - 0.56 ng/ml for female nestlings. The average level of androstenedione for nestling owls was 1.92 - 0.11 ng/ml and levels remained constant throughout development. Levels were significantly higher in males than females. The average androstenedione level was 1.77 - 0.16 ng/ml for male nestlings and 1.05 - 0.24 ng/ml for female nestlings. Hatching order did not affect levels of either androgen. Our results provide a foundation for future studies of androgen production by nestling owls. |
| Genre: | Article |
| ProdID: | 70003571 |
| Citation Author: | Kozlowski, Corinne P.; Hahn, D. Caldwell |
| Citation Contributing Office: | Patuxent Wildlife Research Center |
| Citation Datum: | |
| Citation Day: | |
| Citation Edition: | |
| Citation Editor: | |
| Citation End Page: | 761 |
| Citation Issue: | 4 |
| Citation Keywords: | |
| Citation Language: | English |
| Citation Larger Work Title: | Wilson Journal of Ornithology |
| Citation LatN: | |
| Citation LatS: | |
| Citation LonE: | |
| Citation LonW: | |
| Citation Month: | |
| Citation No Pagination: | |
| Citation Number Of Pages: | 7 |
| Citation Online Only Flag: | |
| Citation Phsyical Description: | 7 p. |
| Citation Projection: | |
| Citation Public Comments: | |
| Citation Publisher: | Wilson Ornithological Society |
| Citation Series: | |
| Citation Series Code: | |
| Citation Series Number: | |
| Citation Search Results Text: | Developmental changes in serum androgen levels of Eastern Screech-Owls (Megascops asio); 2010; Article; Journal; Wilson Journal of Ornithology; Kozlowski, Corinne P.; Hahn, D. Caldwell |
| Citation Start Page: | 755 |
| Citation Volume: | 122 |
| Citation Year: | 2010 |
| Type: | citation/reference |
| Text: | Developmental changes in serum androgen levels of Eastern Screech-Owls (Megascops asio); 2010; Article; Journal; Wilson Journal of Ornithology; Kozlowski, Corinne P.; Hahn, D. Caldwell |
| URL (THUMBNAIL): | http://pubs.er.usgs.gov/thumbnails/outside_thumb.jpg |
| URL (DOCUMENT): | http://www.bioone.org/doi/abs/10.1676/10-014.1 |
| Date Other: | Mon, 18 Jul 2011 00:00 -0500 |
| Publisher: | Wilson Ornithological Society |
