Photoacceleration of Embryonic Development of Quail (coturnix coturnix) Under Different Stimuli Of Light
Open Access
Author:
Fiscus, Garrett James
Area of Honors:
Biology (Behrend)
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
Michael A Campbell, Thesis Supervisor Michael A Campbell, Thesis Honors Advisor Beth Ann Potter, Faculty Reader
Keywords:
Photoacceleration photoperiod avian heart rate egg mass
Abstract:
In wild birds, incubation period and embryonic development time vary systematically with latitude. Incubation periods tend to be longer at the equator and shorter at higher latitudes. This is a paradox; according to basic developmental and biochemical theory (i.e., Q10 factors), higher temperatures (low latitudes) should decrease development times, while cooler temperatures (high latitudes) should prolong them. In poultry, incubation periods can be experimentally shortened by exposing eggs to light. The positive influence of light on embryonic growth, called photoacceleration, can begin within hours after an egg is laid and with a low threshold of light intensity (~10 lux). We used photoacceleration to manipulate developmental times at simulated high and low latitudes. To do this, we artificially incubated quail (Coturnix coturnix) under two conditions: i) varying photoperiods, and ii) varying wavelengths, and measure heart rate as a surrogate embryonic metabolic rate during light and dark phases. We believe that metabolic/heart rates during both light phases and under blue light will be high enough to account for the differences in incubation periods between birds. We hope to provide support for the testable hypothesis that differences in photoperiod and wavelength may influence variation in the rate of embryonic development in birds.
