Embryonic and posthatching development of the barn owl (Tyto alba): Reference data for age determination
✍ Scribed by Christine Köppl; Eva Futterer; Bärbel Nieder; Ralf Sistermann; Hermann Wagner
- Publisher
- John Wiley and Sons
- Year
- 2005
- Tongue
- English
- Weight
- 674 KB
- Volume
- 233
- Category
- Article
- ISSN
- 1058-8388
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
The normal development of the barn owl was documented with the intent of providing a guideline for determining the maturational stage of embryos and posthatching individuals. Embryonic development up to stage 39 could be well described using the well‐known developmental atlas for the chicken (Hamburger and Hamilton [1951] J. Morphol. 88:49–92). For later stages, limb size was established as a suitable indicator. In addition, measuring the egg's vascularized area through candling was found to be a useful, noninvasive method for staging very early embryos, up to stage 25. An average relationship between incubation period and embryonic stage was derived, which showed that development in the barn owl initally lags that in the chicken. For posthatching individuals, skeletal measures (tarsal and ulnar length, skull width and length) were the most reliable parameters for judging maturation, up to 1 month. For older individuals, feather development (e.g., length of primary wing feathers) provided the only cue. Developmental Dynamics 233:1248–1260, 2005. © 2005 Wiley‐Liss, Inc.