Our CSU Extension staff are helping students at Fremont Elementary and Penrose Elementary study embryology by hatching chicken eggs. Both schools and the CSU Extension office have setup incubators and will conduct experiments throughout the hatching process.
April 30, 2008 - Nine chicks so far! Stop by and visit the CSU Extension office.
April 29, 2008 - Day 21
Chick hatches.
Although used only to break through the shell, the egg tooth serves its critical purpose well.
April 28, 2008 - Day 20
Yolk sac completely draws into body cavity. Embryo becomes chick, breaks amnion and starts breathing air in air cell. Allantois ceases to function and starts to dry up.
April 27, 2008 - Day 19
Yolk sac draws into body cavity through umbilicus. Embryo occupies most of space within egg except air cell.
April 26, 2008- Day 18
Growth of embryo nearly complete.
April 25, 2008 - Day 17
Beak turns toward air cell, amniotic fluid decreases and embryo begins preparation for hatching.
April 24, 2008 - Day 16
Scales, claws and beak becoming firm and horny.
Embryo fully covered with feathers.
Albumen nearly gone and yolk increasingly important as nutrient.
April 23, 2008 - Day 15
Small intestines taken into body.
April 22, 2008 - Day 14
Embryo turns its head toward blund end of egg.
April 21, 2008 - Day 13
Scales and claws become visible.
Body fairly well covered with feathers.
April 20, 2008 - Day 12
Toes fully formed.
Down feathers visible.
April 19, 2008 - Day 11
Days 10 to 12 tend to run together. No different changes visible on these days.
April 18, 2008 - Day 10
Beak starts to harden.
Skin pores visible to naked eye.
Digits completely separated.
April 17, 2008 - Day 9
Embryo begins to look bird-like.
Mouth opening appears.
April 16, 2008 - Day 8
Feathers begin to form.
April 15, 2008 - Day 7
Digits on legs and wings become visible.
Abdomen becomes more prominent due to development of viscera.
April 14, 2008 - Day 6
Beak and egg tooth begin to form.
Main division of legs and wings.
Voluntary movement begins.
April 13, 2008 - Day 5
Proventriculus and gizzard formed.
Formulation of reproductive organs - sex division.
April 12, 2008 - Day 4
Beginning of formation of tongue.
Embryo completely separates from yolk sac and turns on left side.
Allantois breaks through amnion.
April 11, 2008 - Day 3
Beginning of formation of beak, wings, legs and allantois. Amnion completely surrounds embryo.
April 10, 2008 - Day 2
24 Hours - Embryo begins to turn on left side.
24 Hours - Blood vessels appear in the yolk sac.
24 Hours - Major developments visible under microscope.
25 Hours - Beginning of formation of veins and heart.
30 Hours - Second, third and fourth vesicles of brain clearly defined, as is the heart, which starts to beat.
35 Hours - Beginning of formation of ear pits.
36 Hours - First sign of amnion.
46 Hours - Formation of throat.
April 9, 2008 - Day 1
Eggs are placed into the incubators. Major developments visible under the microscope are:
18 hours - Appearance of alimentary tract.
19 hours - Beginning of brain crease.
20 hours - Appearance of vertebral column.
21 hours - Beginning of formation of brain and nervous system.
22 hours - Beginning of formation of head
23 hours - Appearance of blood island.
24 hours - Beginning of formation of eyes.