Embryology Informationfor Teachers and Volunteers

NC State University Dept. of Poultry Science

NC Cooperative Extension Servicewww.poultry4h.info

Incubation Times

»Chicken: 21 days

»Turkey: 28 days

»Bobwhite Quail: 23 days

»Duck: 28 days

»Muscovy Duck: 36 days

»Ostrich: 42 days

**Incubation times are not concrete – there are lots of variables

Project Expectations

• Chicks never go home with students

• Find a home for chicks before starting project

• This is not just a chick hatching project

• Actively involve youth

• Candle Eggs regularly

• Keep Records

• Help youth observe embryonic development

How do I successfully hatch Eggs?

�Proper Preparation & Planning

�Quality Fertile Eggs

�Student Buy In

�Good Incubation Management

�Patience

How can I tell if the egg is fertile?

FertileInfertile

Solid dot halo

Quality Fertile Eggs

halo

Incubator Preparation�Secure incubator in advance

�Clean incubator�Avoid strong contaminants

�25% bleach solution

�Setup and test incubator a week before your project is to begin

�Use 2 thermometers

�Incubator location• Avoid drafts, direct sunlight, heat & AC outlets

Preparation and Planning

• Inform coworkers and custodial staff

• How to handle

– Power outages?

– Lower school temps on weekends?

– Tampering

Egg Basics

Start Up Day

• Have the incubator ready to go

• Once the eggs arrive

– Gently clean any dirty eggs with sandpaper or nail file

– Don’t ever wash eggs

– Put a number on the large end of each egg

– Put “X” and “O” on side of each egg

Candling eggs

Good qualityGood quality

hatching egghatching egg

Poor qualityPoor quality

large air cell large air cell

dark yolkdark yolk

CrackedCracked

Two YolksTwo Yolks

Air cell

Goal of Incubation

Oxygen

Water

Carbon dioxide

Temperature

• Embryonic development very sensitive to temperature

– Embryos cannot tolerate elevated temperatures

– even for short periods

• Optimum Temperature: 99.5°F• 98.6°F - 100.4°F

• Start 48-72 hrs prior to setting eggs regulating temperature *Try to maintain 99.5°F*

– Minimize time with lid off incubator

Relative Humidity

• Circulating tray and Thermal tray– ALWAYS have water in circulating tray

– Put water in Thermal tray for last few days

• Sponges can be used to supplement humidity

• Minimize time with lid off incubator

↑ relative humidity = ↓ water loss = LATER hatch time

↓ relative humidity = ↑ water loss = EARLY hatch time

Maintaining Humidity

• Use of water pans

– Surface area NOT depth of water

• Importance for chick health

– Prevent sticking to shell

– Keeps amnion fluid

– Provides for free embryo exercise

– Prevent crippled chicks

Egg Turning

• Rotate no less than 3 times per day

• Odd number of times

• Use an XO system – chart

• Must be turned at least 3 times per day – even

on weekends – cannot be turned too much!

• Turning prevents the embryo from sticking to the

shell membranes

• Stop turning on day 19

Sanitation

• Need to sanitize incubators

– before and after each use

– Use Clorox type solution

• Hand washing

Brooding

• Brooder Box – Very Basic Accommodations

– Cardboard could be a fire hazard

– Must Provide Basic Needs:• Feed • Water

– Marbles in waterer

– Jar lid

• Heat – Heat Lamp

• Clean Environment

1 Day

Embryo

Enlarged Halo

16 Day Embryo with yolk sac

18 Day Embryo with a

malposition

head between the legs

19 Day Embryo with head tucked under right wing

20 Day internal pip

CAM not completely formed

Embryo inside the CAM

A look at what is inside the shell!

Which will NOT hatch?

Yolk sac

drawn in

Shell and the

shell membranes

Inner & outer

shell membranes

(humidity)

Embryonic Development

Turkey as an example of the stages

Embryonic Development

• Web of blood

vessels appears

• (area of

Vasculosa)

**Heart starts to beat**

Embryonic Development

• Heart is easily seen

– 4 chambers

• Compare to day 3

Eye can be seen Head begins to grow

• Main joints begin forming Legs and wings

Limb buds can be seen

**Pipping tooth can be seen**

Pores begin to develop Beak can be seen

Toes begin to form

Follicles cover body

Scales and Claws begin to form Pipping (Egg) tooth

Down begins to grow

Down Growing

**Down covers

the body**

• Development is complete

• Poult enters final growth stage

• Chicks would be hatching

• Days 22 - 25

• poult begins to turn and absorb yolk sac in preparation for hatching

Poult Embryonic Development

Turning is complete Pipping Starts

**Yolk is completely absorbed** Hatching begins