Normal Chicken Embryo Development

By

Akrum Hamdy

Extra embryonic Membranes

• Protect and nourish the embryo

• Terrestrial vertebrates have four extra embryonic membranes

1. chorion

2. amnion

3. allantois

4. yolk sac

1. The chorion and amnion enclose the embryo– The chorion surrounds the entire embryo

• in birds and reptiles it functions in gas exchange

– The amnion encloses the embryo and forms an open volume between the embryo & the amnion called the amniotic cavity

• The amniotic cavity fills with amniotic fluid, which envelops the embryo and cushions it

2. The allantois is an outgrowth of the gut• In reptiles and birds, it stores nitrogenous wastes

3. The yolk sac encloses the yolk in vertebrates with yolk-rich eggs

– In humans, there is no yolk sac, but the yolk aids in formation of red blood cells

Extra embryonic Membranes

Chicken embryo, 21 hours.

Credit: © Carolina Biological/Visuals Unlimited 310816

Primitive streak & groove

Chicken embryo, 43 hours.

Credit: © Carolina Biological/Visuals Unlimited 310877

amnion

somites

heart

Spinal chord

Chicken embryo, 60 hours.

Credit: © Carolina Biological/Visuals Unlimited 310880

eye

somitesSpinal chordamnion

allantoisheart

Chicken embryo, 8 days.

Credit: © Carolina Biological/Visuals Unlimited 310882

Chick embryo, 9 days.

Credit: © Carolina Biological/Visuals Unlimited 214169

Effect of aspirin in chick embryo development

• Each group will set up three containers – Each container has one chick embryo, 2

additional albumens

1. Negative control

2. Negative control (Ringers solution)

3. Experimental (aspirin in ringers solution)

Effect of aspirin in chick embryo development

– Keep everything as sterile as possible!!

– Make observations daily (except weekends)

– Share observations with other members of your group

– Make drawing and written descriptions of your observations.

Chick embryo, 13 days.

Credit: © Carolina Biological/Visuals Unlimited 214173

Chick embryo, 16 days.

Credit: © Carolina Biological/Visuals Unlimited 214176

Chick embryo, 19 days.

Credit: © Carolina Biological/Visuals Unlimited 214179

Newly hatched chick on day 21.

Credit: © Jerome Wexler/Visuals Unlimited 211077