Poultry_Science_2-2 - . most concentrated in retina, n...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Melatonin peaks during dark phase. Light prohibits melatonin production.  Light   Dark   Light Melatonin: promotes sleep.                   Inhibits reproduction n activity.  Corticosterone peaks right when the light n dark meets. Stimulates you to  wake up.  Melatonin will stimulate ??. There is evidence that food intake is another Zeitgeber.  Severe food restriction eliminates the diurnal rythym in corticosterone  Food restriction leads to chronically elevated corticosterone  concentrations  Circannual cycles also rely on  -innate internal clock  - Zeitgebers.  Clock genes: nothing controls them.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: . most concentrated in retina, n those other two pineal. Period, clock, banal. As day length grows longer 12-14 hrs. the light period and the light peak (when you are absolutely sensitive to light. When u have the pulse of light, its called the clock shift. A single pulse of light can trigger spring like response in birds. Clock-shift: changing the SOME TROPICAL BIRDS DO NOT FOLLOW 12 MO CYCLES. SOOTY TERNS ON ASCENSION ISLAND ON THE EQUATOR BREED EVERY IN BIRDS: THE TESTES ENLARGE GREATLY DURING THE BREEDING SEASON. REPRESENTS A NEW PUBERTY EVERY YEAR....
View Full Document

This note was uploaded on 04/08/2011 for the course POUL 3123 taught by Professor Navara during the Spring '09 term at University of Georgia Athens.

Page1 / 2

Poultry_Science_2-2 - . most concentrated in retina, n...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online