1. 4-H Embryology
Penn State
4-H
Responsibility!

2. 4-H Pledge I pledge my Head to clearer thinking
my Heart to greater loyalty
my Hands to larger service
and my Health to better living
for my club, my community
my country and my world.

3. What is Embryology?
Embryo + ology

4. Embryology = the study of the beginning of life of any living thing
What is Embryology?
Embryology = the study of the beginning of life of any living thing

5. Let’s talk about chickens…

6. Rooster = Male
Hen = Female

7. 5-6 months old
Albumen
Pigment
How long to
make an egg?
Green
Notebook
Page 6

8. That’s the hen, what about the rooster?
The hen produces this egg independently.
This egg has hen cells only.
This egg will not develop an embryo.
This is the type of egg you buy at the grocery store.
This egg is INFERTILE. H
When hens and roosters are together they mate
and the hen produces this egg.
This egg has hen and rooster cells.
This egg will develop an embryo.
This is the type of egg in the incubator.
This egg is FERTILE. H R

9. Shell
Outer Shell Membrane
Inner Shell
Membrane
Air Cell
Albumen
Chalazae
Yolk
Small, white
Blastodisc
-Infertile
Blastoderm - Fertile
4 x larger, tan, circle
Page 4

10. Incubation
Natural Incubation: the hen sits on the eggs until they hatch.
Artificial Incubation: use an incubator and copy the hen’s actions
until the eggs hatch.
4 Components of Incubation:
Temperature
Humidity
Exercise
Clean, fresh air
Page 3

11. Page 7

12. Candling
Day 4 embryo

13. 4
The embryo looks like a spider.
Label:
Air Cell
Embryo
Blood Vessels
Yolk
Albumen
Shell
Page 13

14. The embryo looks like a spider.4
The embryo looks like a spider.
Homework:
Page 3-reading
Page 4-bottom
Page 5-top
Page 13-drawing
Shell
Air Cell
Yolk
Embryo
Albumen
Blood Vessels
Page 13