Wh

y M

Ea

su

rE

Eg

gs

hE

LL t

EM

pE

rat

ur

E?

02

Region for measuringeggshell temperature

•Theonlyequipmentrequiredformeasuringeggshelltemperatureisamedicalinfraredearthermometer.

• ItisrecommendedtouseaBraunThermoscanexacTemp(ModelIRT4520,type6022).

•Correctregionformeasuringshelltemperatureisshownbelow.

tHe PRoceDuRe FoR MeAsuRINg eggsHeLL teMPeRAtuRe

How to...MeasureeggshellTemperature

03

•Theobjectiveistosampleeggswithinthemachinefromlocationsontheleftandright,frontandbackandtop,middleandbottomofthesetter.Theexactlocationswillvarywithmachinedesignbutattempttocoverallareasofthesetter.

•donotchosetraysattheverytoporbottomofthetrolleyorrack.

•Chooseeggsinthecenteroftheincubatortraytomonitor;thoseattheedgesofthetraywillbecooler.

•Togetacompleteprofileofthesetter,eggswillneedtobemonitoredateachstageofincubation.

ThEPrOCEdurEFOrMEaSurINgEggShEllTEMPEraT

urE

03

Where anD When to CheCk eggshell teMperature

Thermal image of eggs on a setter tray. Note that the temperature of the air cells and eggs at the edge of the tray is cooler than temperature at the equator of eggs in

the center of the tray.

38.3oC/100.9oF

30.9oC/87.6oF

How to...MeasureEggshellTemperature

03

ThEPrOCEdurEFOrMEaSurINgEggShEllTEMPEraT

urE

04

step 1: Checkthatthemeasuringtipofthethermometeriscleanandthatithasanewplasticcoveron.(Someolderthermometertypesmayneedtobekeptatincubationtemperaturefor30minutespriortousetopreventanerrormessage).

step 2: Planwheretosampleeggshelltemperaturesbeforeopeningthesetterdoor,sothatitwillbepossibletoworkquicklyonceinside.Ensureeachareaofthesetterismonitored.

step 3: Ifitisnotpossibletoworkinsidethesettersafelywhileitisoperating,turnitoffandmeasureasmanyeggsaspossiblein10minutes.Ifitisnotpossibletomeasureeggsatalllocationswithin10minutes,closeandrestartthesetterandreturnafter30minutestocompletethemeasurements.

step 4: Measureshelltemperatureattheequatoroftheegg,notatthetoporbottom.Makesurethetipofthethermometerisflatagainsttheeggshellsurface.

step 5: Sample3eggsfromthecenterofeachsettertray.Foreggsinthesecondhalfofincubation,rejectanymeasurementthatissignificantlycooler(>0.4°C/0.7°F)thantheothereggsonthetrayasitislikelythereisnoembryointheegg.

step 6: recordresults.determineaverageeggshelltemperatureandspreadofeggshelltemperatures.

step 7: Compareresultsagainstgraphonpage5todetermineifincubationtemperaturecorrect.

How to...MeasureEggshellTemperature

03

INTE

rPrETINgrESulTS

05

InterpretIng eggshell teMperature

•Theobjectiveisformostoftheeggstobewithintheidealtemperaturerange(37.8–38.3oC/100–101oF)throughouttheincubationperiod.

• Insingle-stagesystemsthisisachievedbyadjustingthetemperatureprogramateachageofincubation.

• Inmulti-stagesystemswhereonlyonetemperaturesettingcanbeused,theremayhavetobeacompromisebetweentherequirementsforthestartandtheendofincubation.Itisprobablethatatthestartofincubationitwillbenecessarytohaveeggscoolerthanidealinordertoensurethateggsdonotbecometoohotattheendofincubation.

•highincubationtemperatureisnormallymoredamagingthanlowincubationtemperature.

• Ifthereisawidespreadofeggshelltemperaturesacrossonemachineitmayindicatethatitneedsmaintenance.

97

100

98

99

101

102

103

36.1

37.8

36.7

37.2

38.3

38.9

39.4

1 2 3 4 5 6 117 128 13 169 14 1710 15 18

Day of Incubation

she

ll te

mp

erat

ure

(oC

) shell tem

perature ( oF)

Danger

risk

Ideal

risk

Delayed hatch

How to...MeasureEggshellTemperature

03

INTE

rPrETINgrESulTS

06

sIngle-stage MaChInes MultI-stage MaChInes

Note: Prior to any alteration of setter operating temperatures, ensure that there are no

maintenance problems with the machine.

Danger risk Ideal risk Delayed hatch

Note: Prior to any alteration of setter operating temperatures, ensure that there are no

maintenance problems with the machine and multi-stage loading of the setter is correct.

Temperatureswithinidealrange:noadjustmentsrequired.

Temperatureswithinidealrange:noadjustmentsrequired.

Temperaturesfromday14onwardstoohigh:lowerincubatortemperaturetobringday14-18

temperaturesintoidealrange.

Temperaturesatthestartofincubationinlowriskareaandattheendofincubationwithinthehighriskarea:

noadjustment.

Temperaturesfromday8-10toolow:increaseincubatortemperaturetobringday8-10temperatures

intoidealrange.

Temperaturesfromday16onwardindangerrange:lowerincubatortemperaturetobringday16onward

temperaturesintoriskrange.

36.1

37.8

36.7

37.2

38.3

38.9

39.4

1 2 3 4 5 6 117 128 13 169 14 1710 15 18

Day of Incubation

she

ll te

mp

erat

ure

(oC

) shell tem

perature ( oF)

36.1

37.8

36.7

37.2

38.3

38.9

39.4

1 2 3 4 5 6 117 128 13 169 14 1710 15 18

Day of Incubation

she

ll te

mp

erat

ure

(oC

) shell tem

perature ( oF)

36.1

37.8

36.7

37.2

38.3

38.9

39.4

1 2 3 4 5 6 117 128 13 169 14 1710 15 18

Day of Incubation

she

ll te

mp

erat

ure

(oC

) shell tem

perature ( oF)

36.1

37.8

36.7

37.2

38.3

38.9

39.4

1 2 3 4 5 6 117 128 13 169 14 1710 15 18

Day of Incubation

she

ll te

mp

erat

ure

(oC

) shell tem

perature ( oF)

36.1

37.8

36.7

37.2

38.3

38.9

39.4

1 2 3 4 5 6 117 128 13 169 14 1710 15 18

Day of Incubation

she

ll te

mp

erat

ure

(oC

) shell tem

perature ( oF)

36.1

37.8

36.7

37.2

38.3

38.9

97

100

98

99

101

102

103

97

100

98

99

101

102

103

97

100

98

99

101

102

103

97

100

98

99

101

102

103

97

100

98

99

101

102

103

97

100

98

99

101

102

10339.4

1 2 3 4 5 6 117 128 13 169 14 1710 15 18

Day of Incubation

she

ll te

mp

erat

ure

(oC

) shell tem

perature ( oF)

exaMples oF teMperature proFIles

MeasureEggshellTemperature

03

How to...

Wh

y M

Ea

su

rE

Eg

gs

hE

LL t

EM

pE

rat

ur

E?

01

WHy MeAsuRe eggsHeLL teMPeRAtuRe?•Correctsettertemperatureiscriticalforhatchinggoodqualitychicks.

•settertemperatureiswhatisexperiencedbytheembryoinsidetheegg.Itisnottheairtemperatureofthesetter.

•eggshellsurfacetemperatureiscloselyrelatedtointernaleggtemperature(seegraphbelow).Itisthereforeausefultoolfordeterminingwhetherornotsettertemperatureiscorrect.

•shelltemperaturecanbeeasilymeasuredusingamedicalinfraredthermometer.

•Optimumshelltemperatureformaximumhatchandchickqualityis37.8-38.3oC(100-101oF)throughoutthewholesettingperiod.

•knowledgeofeggshelltemperaturesallowssettertemperaturestobeadjustedtooptimizeconditionsfordifferencesinembryoheatproductionandmachinedesign.

•Measurementofeggshelltemperatureshouldbeusedtoestablishthecorrectmachinetemperaturesettingforthetypeofeggthatisbeingincubatedandforthedesignofsetter.

• Itshouldnotbeusedforcalibratingsettersorcheckingmachinetemperatureuniformity.

Measuredinternaleggandeggshelltemperatureduringtheincubationperiodwhenincubatedataconstanttemperature–basedonTazawa&Nakagawa(1985)andFrench(1997)

1

37.2 99

37.8 100

38.3 101

2 3 4 5 6 7 8 9 10Day of Incubation

Incubatoreggshell

tem

per

atur

e (°

c) tem

perature (°F)

11 12 13 14 15 16 17 18 19 20

How to...MeasureeggshellTemperature

03

Measure Eggshell Temperature.03