Fall - Auburn University Repository
Fall - Auburn University Repository
Fall - Auburn University Repository
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J. R. HOWES, Dept. of Poultry Science<br />
WALTER GRUB and C. A. ROLLO,<br />
Dept of Ag~ricultural Etigifeering<br />
Call wXith statndt Sevecit st tiine 1cl i)cl itiot is<br />
bectteri that) mrost othiei aliials. TIie<br />
tcamelt's hbeat to~lerance has1 lbec'tt kioxx i<br />
ftti a long tunle, buit olnix i ccelntlv has<br />
tI is ciharacteistAic of the chicken 1becn<br />
learnied.<br />
Sitin iner strie(ss is a tet ii ctined to dIi<br />
scibei thle sti ess to wxh ichlilan atll' inv<br />
expttsed duinPg suimmet. It r epreseit,<br />
total (dis1ruptiotn inl lil aitnals norioal<br />
we lilceing caused'( i~x heait. huidiitx<br />
light radliatitnt and othter factoirs.<br />
Pt tit Il tl are I)CCom-ing' ineasittglx<br />
axi at of itt Ie en xi ott met t inl their ciftorts<br />
to ccot il inicalix, pitodiuce eggs at t (<br />
neat. This is cevidettced Ixv the itncreasing<br />
number 1ic of iiit tttihle(i enirionmet<br />
hoitses ht'iig constiructedi.<br />
One reasoin the Soittheastern Ultiftcd<br />
States is not at leatit ig eggu-pt iditctittn<br />
area is bccattse of diffhcuitx etncoutitered<br />
inl e tntt in icalv ixfroditciir nf0C t(h~diialitx<br />
eggs duiriing the ltong, liot and humid<br />
sit inn er ti 't' v patrts of the i atioti cxper<br />
ience hecat stress inl short periods<br />
xxhein temitperatture (roes xxell oxe c 1000)<br />
F'. WheItn this happens, it is itot wicommutt1<br />
fotr hundreds of ibirdis to (lie as a<br />
resl t of the sudden fiiiflux of ii ttei t x<br />
65<br />
60<br />
55<br />
So2l 4 5<br />
e<br />
90*F<br />
The graphs show effect of high temperature<br />
on laying White Leghorn pullets in <strong>Auburn</strong><br />
experiments. There were 80 birds to each<br />
treatment, all on 14 hours light daily and<br />
6000 relative humidity and ventilated at 1<br />
cu. ft. per minute per bird.<br />
VH MER STRES<br />
aL1"NG POULTR<br />
cxpierieinced inl the Southeast. btut thi's<br />
airea i s liietd xwithi suniiflei sttress<br />
th at uisiaaliy h ists foI r sexveral m1oit tIs.<br />
The first lpritlit is ttt i(Iet tifx, the<br />
niin stress factors. TIhis is lieesxarx<br />
to ectulitttticatllx comibat the situiation ilt(]<br />
ibitdics -iiicrutsedt'l icit lotsses antirc<br />
diilced hecat proi t ctit U in th l li d vlx. To<br />
step-n i heat lisses, respira ~t iuon is ittcreased<br />
I panttitg ), lood stiilY ini tile<br />
skini is incireased. xxitigs are( flexed, and<br />
thle birds dlrink ire xxalter. Ruedutced<br />
h1eat pitodluct ion r esutlts frit it retiu ced<br />
prtoduce env'ironmnle ts iargex' free of thle<br />
factors that redtuce egg pirtduictiiin.<br />
Frtont wotrk at AXnhurit anid elsewhere,<br />
i .t appears that hiimiditx reduces egg<br />
prducrtiont and grtx l u~x at tile highlest<br />
tempileratur es. lThis, humidity protlabl<br />
s is otie otf thle lesser evils.<br />
Ptreviotuis reseatrch has sihowxni tat<br />
chaniges itt day ienigthi stimuliate egg produtetioit<br />
antd gruixxth. Sinice chaniges inl<br />
dax' length duiritig Ma "v tot Au gust are<br />
reiatixe 'lx small, patrt of tie aitx erse still)<br />
iner effects mnight he blamied onl lack of<br />
chanige inl dav ienigtht. Ilt xxexer, the extetidcd<br />
1 icrimtd of high termperaturte (at<br />
leatst 4 niionths ) xx iulci appeair to he the<br />
main cause of suimmer stiress iii tfhe Soithelist.<br />
Phx sitl ogists itt D~uke Uiixersitx haxve<br />
actixvity', afppetite, grit lt egg proitti<br />
ttiiit. egg size, aid t~ertilitx.<br />
Effect of high temper atiures tnt egg<br />
xwei ght andii egg fprtodu ictPit is iiliust rated<br />
bx thle graiph. Thetse datai sltixx that<br />
WXh ite Leghoin plicts 1 produ1ce tx a Ii,<br />
(plate goiod eggs at 80) F. It xx:is alsot<br />
ftttitid that these hit os pi tdlice its xxel<br />
at 80) F. ats it .50-60t) F. '[hiis is cotj<br />
trat x tt earlier, limited oiitrk elsexxhere<br />
that sihoxwed 5t0 (0tt F. its the btest tein<br />
petl re for layinitg p~lltl i It.<br />
USD)A xwork hast inidicated that birdis<br />
xwill itot suiti vxe att 100 Ft . atd 6I0%t' relatixve<br />
hittuidits . lliixxei r, ill Aithititi stitdiis<br />
fenliaies nott oitti ixedl under thiese<br />
condtcitiions hut proiduicetd eggs. Slttxx ii<br />
it) the photogiap )l iret liay'is pating ill<br />
cxrevele h imx catmels atre alct to slit x x<br />
ill ilitel ise deseirt lIctat. O il ottf the ilhaiti<br />
mlechailttills pe~rmittinig suitvxal is thle<br />
Based ott the Aitinit ri eseartch resulits,<br />
Ilarge ratnge iii bod 'iv t ciii utratu ite lietxxctt<br />
iiidax atid mitight ( 18-9;3<br />
F.) . Thie camtel is alte to "load" heat<br />
durinig thle (lax anid "uniloa.d" it difntg<br />
the cooiler ntight.<br />
Atubuiirn research in dicates that thle<br />
thicketi potssesses the satiie ltlilitx a is thic<br />
cal.d bu t to at nite lIiIesser diegree.<br />
Thits. chickenis call suiit ic andi prtidtce<br />
iti11IIh hetter if hot datxs ate reliexved b\x<br />
cooul itiglits thlt tlidter conitiinuouis high<br />
temperatures.<br />
Whlt exposed to heat, thicre aic( txx I<br />
actiions that hell) chicketix intitttaiit thetir<br />
col leter] titig heat "tress. inl pultryx itit<br />
heed lex isitig. Especiatllx, ftrint the stitndtpioint<br />
ot ft(e Soiutheatst. results ilioicteo<br />
tha~t lain lg Wh'lite LeglLorti putllets xxill<br />
adtl t~el) \prdutce P xx liii thett telitp)raitorIe<br />
is als high ats 80'- F. Sitce It nalt<br />
nott (eetinlg himtself ill lcix xwxirik lit.<br />
gills to) perspirte at abilitt F., the<br />
piultrx tnait catn seixve its his oxx] it territtiltem.<br />
Whl the itpinattit ht'gii s tio<br />
feel iitit'tiifoit,itc lit' call ainciif his<br />
htells art likesc n fifected. This xxoiuldi<br />
Ibe his signalt to tatke pra ~ctical steps.<br />
illix iatt high tettiptt ,titt s.