Relationship Between Incubation Temperature and Egg Size with Heart Hypoplasy in Broiler Chicks at Hatching

Transcription

1 Interntionl Journl of Poultry Siene 11 (12): , 2012 ISSN sin Network for Sientifi Informtion, 2012 Reltionship etween Inution Temperture n Egg Size with Hert Hypoplsy in roiler hiks t Hthing Vivine e Souz Morit, Isel ristin oleli n João emir Oliveir 1 2 Deprtment of niml Morphology n Physiology, Deprtment of Ext Sienes, Fulty of griulturl n Veterinry Sienes, São Pulo Stte University, UNESP, rzil strt: It ws nlyze if the effets of ontinuous inution temperture evitions uring the seon hlf on the evelopment of oy, orgns n hemtologil respirtory n energeti prmeters iffer etween mle n femle from 30- n 60-week-ol reeer eggs. From y 13, o eggs were expose to 36, 37.5, or 39. t 3, 6, 12, 24, 48 n 72 h fter this hnge in the temperture n t hth, re ells ount, hemtorit, hemogloin, men orpusulr volume, plsm gluose level n oy, liver n hert weights were evlute. Inepenent of inution temperture, sexes n reeer ges, men orpusulr volume erese n the other vriles inrese uring lte inution. In 30-week-ol reeer eggs, oy weights n erythroyti prmeters were not influene y temperture ut liver n hert weights erese inresing inution temperture n gluose level inrese t 36 n 39. In 60-week-ol reeer eggs, mles were hevier t hthing with inution t 36 n femles h smller oy weights with inution t 39. In oth sexes, liver weight erese n gluose onentrtion ws higher t 36 n 39 n hert weights n erythroytes prmeters were not influene y temperture. Inepenent of reeer ge, hthility ws lower t 39. The t show tht high temperture from y 13 of inution reue more intensively the hthing suess n use ri hypoplsi in hiks from 30-week-ol reeer eggs only, reveling for the first time tht the suseptiility for sites synrome, y reue hert evelopment t hthing, is ssoite to reltionship etween inution temperture n egg size. Key wors: ri weight, erythrogrm, gluose, inution, therml stress INTRODUTION Temperture is primry ftor in vin emryoni evelopment within eggs. During morphogenesis whih ours in the first thir of the inution perio, emryoni metolism is low n eggs require het from n inutor; ut, uring the fetl perio in the seon hlf of the inution perio, metolism inreses n the eggs lose het (Frenh, 1997). From y 13 of inution, eggshell temperture of eggs from 30- n 60-week-ol roiler reeers is pproximtely 0.8 higher thn the temperture in the mient inutor (Gulhnone, 2012), llowing het issiption from the eggs. Inepenent of reeer ge n egg weight, the intense growth in emryo oy mss n orgns uring the seon hlf of the inution perio requires mrkely inrese tissue metoli tivity n oxygen emn. This proess neessittes optimiztion of loo gs exhnges (O2 n O2) whih in turn requires hnges in erythroytes prmeters Re loo ell ount (R), hemtorit (HT), hemogloin onentrtion (HG) n Men orpusulr Volume (MV) n in energy isposition. oring to Morit et l. (2009) n Tzw et l. (2011), evelopmentl hemtologil hnges from y 13 of inution inlue mrke inreses in the R, HG n HT vlues, erese in MV vlues n n inrese in the hert mss. These hnges in hemtologil respirtory vriles show tht fetuses respon to higher oxygen emn, resulting from their higher metoli rte, y inresing ri output n inresing the numer ut reuing the volume, of erythroytes to elevte oxygen trnsporttion rte. Oler reeer eggs show higher eggshell onutne thn o young reeer eggs whih is relte to erese eggshell thikness, greter porosity n higher eggshell surfe re of the oler reeer eggs (Morit et l., 2009). Eggshell onutne inreses with egg size ut is not proportionl to inreses in emryoni mss (Meijerhof n Vn eek, 1993), initing tht eggs from oler reeers (hevier eggs) hve greter iffiulty issipting het thn eggs from younger reeers (lighter eggs). oth eggshell onutne n emryoni evelopmentl rte re lso etermine y inution temperture n erese n inrese with low n high tempertures, orresponing uthor: Isel ristin oleli, Deprtment of niml Morphology n Physiology, Fulty of griulturl n Veterinry Sienes, São Pulo Stte University, UNESP, Vi e esso Prof. Pulo Donto stellni s/n, , Jotil 761

2 respetively (Romnoff, 1960; Wilson, 1991; Lenro et l., 2004; Nkge et l., 2003; Morit et l., 2010). Suh ltertions in egg evelopment n eggshell onutne, promote y inution temperture, suggest the possile ptility of the hemtologil respirtory prmeters. lthough literture exists on hemtologil prmeters uring emryoni evelopment (e.g., Tzw et l., 1971,, 1991; 2011), whether inution temperture evitions influene in istint form the evelopment of hemtologil respirtory n energeti vriles for oth sexes in young n ol reeers eggs remins unknown. Thus, the present stuy evlute whether inution tempertures iffering y 1.5 from the usul temperture from y 13 ffet hemtologil respirtory n energeti prmeters, s well s oy, hert n liver growth of mle n femle fetuses n hiks from 30- n 60-week-ol roiler reeers. MTERILS ND METHODS Experimentl esign: Fertile eggs from 30- n 60- week-ol roiler reeers (o), weighing 61±2.61 g (light eggs) n 72±2.94 g (hevy eggs) (signifint ifferent mens, P<0.05) were otine from ommeril hthery (Glooves, Itirpin, São Pulo). For eh reeer ge, eggs were weighe n istriute evenly y weight into six inutors (Premium Eológi IP70) ontining 70 eggs eh n inute for 12 ys t 37.5 ry ul n 30 wet ul, with n utomti turning frequeny of one per hour until y 18. From y 13 of inution until hthing, two inutors were sujete to eh of three tempertures: 36.5, 37.5 n Reltive Humiity (RH) ws mintine t 60% uring ll inution perios. Inution temperture n RH were lso ontrolle y igitl thermohygrometer (Hygrotherm, TF, Germny). nlyze prmeters: t 3, 6, 12, 24, 48 n 72 hours fter inution temperture hnge n t hthing, loo smples were ollete n oy n orgn weights were mesure for six fetuses n newly hthe hiks per sex per inution temperture n reeer ge. The following prmeters were nlyze: oy weight (g, perentge in reltion to egg weight), hert n liver weights, somti inex s perentge of oy weight, hemtologil orpusulr volume (MV, µm ), R (10 /mm ), plsm gluose (GP, mg/l) n hthing n mortlity rtes. oy weights n loo smples were otine prior to eth y ervil islotion for fetuses n hiks. The reltive oy weight ws lulte s perentge of egg weight n the reltive weight of the orgns ws lulte s perentge of oy weight. Fetl loo smples were tken from the llntoi vessels, wheres hthling loo smples were ollete from the jugulr vein. loo smples were ollete into tues ontining EDT (Glist, t. 29; 15 µl/ml loo) n immeitely nlyze. loo smples were entrifuge t 3,500 rpm t 4 for 15 minutes n plsm ws ollete n store t 20 for etermintion of gluose onentrtion using ommerilly ville kit (gluose PP liquiform, 500 ml, t. 84, Ltest Dignósti). ll smples were prepre n nlyze following the mnufturer s reommentions. Two reings per smple were mesure y spetrophotometry t wvelength of 505 nm. Hthility n mortlity were lulte s perentges of inute fertile eggs. Egg weight loss ws lulte s the perentge of egg weight efore inution. For this etermintion, eggs were weighe prior to inution n on y 18 of inution. Eggshell onutne ws lulte oring to hristensen et l. (1994). ll niml hnling protools were pprove y the ommittee of Ethis in niml Use (EU) of the Fulty of griulturl n Veterinry Sienes (protool numer /12), São Pulo Stte University. Sttistil nlysis: For eh roiler reeer ge n sex group, the experiment ws 3x7 ftoril rrngement of tretments, onsisting of three inution tempertures (36, 37.5 n 39 ) n seven ges (3, 6, 12, 24, 48 n 72 hours fter inution temperture mnipultion n t hthing). ll t were nlyze using the GLM proeure of SS (SS Institute, 2000), with ifferent replite numers per tretment. Mens were ompre y F test n Tukey s test using signifint ifferene t P<0.05. RESULTS oy weights: s shown in Tle 1, oy weights of mles n femles from 30-week-ol reeer eggs were influene (P<0.05) y ge n inrese from y 14 of inution (24 hours fter temperture hnge) to hthing. For mles n femles from 60-week-ol reeer eggs, solute oy Weights (W) were ffete y oth ge n temperture. itionlly, for mles, signifint (P<0.05) intertion etween ge n temperture ourre. The W of femles inrese from y 14 n were greter t 39 thn t 36 n There ws no signifint ifferene etween 36 n 37.5 for this prmeter. In mles (Tle 2), W inrese from y 13 of inution t 37.5 n from y 14 t 36 n 39. t hthing, mle hiks from eggs inute t 37.5 n 39 h similr W whih ws greter thn W of hiks from eggs inute t 36. Reltive oy Weight (RW) inrese uring lte inution in oth sexes. In the femle hiks, RW were influene y temperture n were lower (P<0.05) when inute t 36 n 39 ompre to

3 Tle 1: Effets of ge n inution temperture on oy weight (g, %) of mle n femle fetuses n hiks from 30- n 60-weeksol reeer eggs 30 w. ol 60 w. ol solute (g) Reltive (%) solute (g) Reltive (%) ge ()* Mle Femle Mle Femle Mle Femle Mle Femle Hthing Temperture (T) Proility < < < < < < < < T xt : Vlues with ifferent letters (olumns) iffer signifintly y Tukey s test (P<0.05). *ge in hours fter the hnge in the inution temperture (ys of inution) Tle 2: Intertion etween ge n inution temperture on oy weight (g) of mle fetuses n hiks from 60- weeks-ol reeer eggs Temperture ge* Hthing , : Vlues with ifferent letters (olumns n lines, respetively) iffer signifintly y Tukey s test (P<0.05). *ge given in hours fter the hnge in the inution temperture (ys of inution) Hepti weights: The solute n reltive liver weights (LW n RLW, respetively) of mles n femles from 30-week-ol reeer eggs were lerly ffete (P<0.05) y ge n temperture, with signifint (P<0.05) intertions etween these two prmeters (Tle 3). In femles, oth LW n RLW inrese from y 13 of inution (12 h fter the inution temperture hnge). Hepti weight inrese with inution temperture ut RLW remine unhnge t inution tempertures of 36 n 37.5 n inrese t n inution temperture of 39. In mles, LW inrese from ys 13, 15 n 14 t 36, 37.5 n 39, respetively (Tle 4). t hthing, livers were hevier t 36 thn t 37.5 n 39 whih i not iffer from eh other. However, oring to the intertion etween ge n temperture (Tle 4), RLW inrese from y 13 t 36 n from y 14 t 37.5 n 39 n ws lower t hthing with higher inution temperture. LW of mles n femles from 60-week-ol reeers were influene signifintly y ge n inution temperture n RLW ws influene only y ge (P<0.05). LW inrese from y 14 of inution in femles n from y 15 in mles, wheres RLW inrese from y 13 in the mles n from y 14 in the femles. LW ws lower t 36 thn t 37.5 n 39 whih i not iffer from eh other. Hert weights: solute n reltive hert weights of femles n mles from 30-week-ol reeer eggs were signifintly (P<0.05) ffete y reeer ge, inution temperture n the intertion etween these two ftors (Tle 5). oring to this intertion (Tle 6), solute hert weight inrese from ys 14, 15 n 16 of inution t 36, 37.5 n 39, respetively. The effet of temperture on solute hert weight ourre for ll reeer ges. In mles, this prmeter ws higher t n inution temperture of 36 thn t 37.5 n 39, ws similr etween the two ltter tempertures from y 14 until y 16 of inution n iminishe with inrese temperture t hthing. In femles, from y 16 of inution until hthing, solute hert weight ws lower with higher inution temperture. Reltive hert weight ws higher from y 16 of inution ompre with ys 13, 14 n 15 n ws lower t n inution temperture of 39 thn t 36 n In femles, reltive hert weight inrese with ge uner inution t 36 n iminishe t inution tempertures of 37.5 n 39. From y 15, reltive hert weights of femles were higher t n inution temperture of 36 ompre with the two other tempertures n 763

4 Tle 3: Effets of ge n inution temperture on liver weight (g) n somti inex (%) of mle n femle fetuses n hiks from 30- n 60-weeks-ol reeer eggs 30 w. ol 60 w. ol Weight (g) Somti Inex (%) Weight (g) Somti Inex (%) ge ()* Mle Femle Mle Femle Mle Femle Mle Femle Hthing Temperture (T) Proility < < < < < < < < T xt : Vlues with ifferent letters (olumns) iffer signifintly y Tukey s test (P < 0.05). *ge given in hours fter the hnge in the inution temperture (ys of inution) Tle 4: Intertion etween ge n inution temperture for liver weight n somti inex of mle fetuses n hiks from 30- weeks-ol reeer eggs Weight (g) Somti Inex (%) ge* Hthing , : Vlues with ifferent letters (olumns n lines, respetively) iffer signifintly y Tukey s test (P < 0.05). *ge given in hours fter the hnge in the inution temperture (ys of inution) Tle 5: Effets of ge n inution temperture on hert weight n somti inex of mle n femle fetuses n hiks from 30- n 40-weeks-ol reeer eggs 30 w. ol 60 w. ol Weight Somti Inex Weight Somti Inex ge ()* Mle Femle Mle Femle Mle Femle Mle Femle (162 ) Hth Temperture (T) Proility < < < < < < T < < xt < < < : Vlues with ifferent letters (olumns) iffer signifintly y Tukey s test (P<0.05). *ge given in hours fter the hnge in the inution temperture (ys of inution) 764

5 Tle 6: Intertion etween ge n inution temperture on hert weight n somti inex of mle n femle fetuses n hiks from 30-weeks-ol reeer eggs Weight (g) Somti Inex (%) Mle Femle Femle ge ()* Hth , : Vlues with ifferent letters (olumns n lines, respetively) iffer signifintly y Tukey s test (P < 0.05). *ge given in hours fter the hnge in the inution temperture (ys of inution) Tle 7: Effets of ge n inution temperture on hemtologil prmeters of mle n femle fetuses n hiks from 30-weeksol reeer eggs Mle Femle ge ()* HT (%) HG (g/l) 6 3 R (10 /mm ) 3 MV (µm ) HT (%) HG (g/l) 6 3 R (10 /mm ) 3 MV (µm ) Hth Temperture (T) Proility < < < < < < T xt HT: Hemtorit, HG: Hemogloin, R: Re oy ount, MV: Men ell volume. - : Vlues with ifferent letters (olumns) iffer signifintly y Tukey s test (P < 0.001). *ge given in hours fter the hnge in the inution temperture (ys of inution) erese with inresing temperture from y 16 of hours n from 72 hours to hthing. Tle 8 shows tht inution. In mles n femles from 60-week-ol in mles from 60-week-ol reeer eggs, HT vlues reeer eggs (Tle 5), oth solute n reltive hert inrese from 12 to 24 hours n from 72 hours to weights were influene signifintly (P < 0.05) only y hthing; HG inrese from 6 to 24 hours n from 72 ge n inrese from y 14 of inution until hth. hours to hthing n R vlues inrese from 72 hours to hthing, wheres MV vlues erese from loo prmeters: Inepenent of roiler reeer ge, 72 hours to hthing. In femles from 60-week-ol in oth sexes, ll nlyze respirtory loo prmeters reeer eggs, HT vlues inrese from 12 to 24 were signifintly (P < 0.05) influene only y emryo hours n from 72 hours to hthing; HG inrese ge (Tle 7 n 8). s shown in Tle 7, in mles from from 72 hours to hthing; n R vlues inrese 30-week-ol reeer eggs, oth HT n R vlues from 12 to 24 hours n from 72 hours to hthing. MV inrese from 24 to 48 hours (ys 14 n 15 of vlues erese from 72 hours to hthing. Levels of inution) n from 72 hours to hthing. HG vlues loo gluose were signifintly (P < 0.05) ffete y inrese from 24 to 48 hours n then remine ge n inution temperture in oth sexes n unhnge until hthing, wheres MV vlues roiler reeer ges. In mles n femles from 30- erese from 12 to 24 hours n from 72 hours to n 60-week-ol reeer eggs, loo gluose levels hthing. In femles from 30-week-ol reeer eggs, inrese from 72 hours to hthing n from 12 hours HT, HG n R vlues inrese from 24 to 48 to hthing, respetively. Inepenent of roiler reeer hours n the vlues were mintine from 48 hours to ge, mles presente higher gluose levels t n hthing, wheres MV vlues erese from 12 to 24 inution temperture of 39 thn t 37.5, wheres 765

6 Tle 8: Effets of ge n inution temperture on hemtologil prmeters of mle n femle fetuses n hiks from 60-weeksol reeer eggs Mle Femle ge ()* HT (%) HG (g/l) 6 3 R (10 /mm ) 3 MV (µm ) HT (%) HG (g/l) 6 3 R (10 /mm ) 3 MV (µm ) Hth Temperture (T) Proility < < < < < < T xt HT: Hemtorit, HG: Hemogloin, R: Re oy ount, MV: Men ell volume. - : Vlues with ifferent letters (olumns) iffer signifintly y Tukey s test (P<0.01). *: ge given in hours fter the hnge in the inution temperture (ys of inution) Tle 9: Effets of ge n inution temperture on plsm gluose levels (µg/µl) of mle n femle fetuses n hiks from 30- n 40-weeks-ol reeer eggs 30 w. ol 60 w. ol ge ()* Mle Femle Mle Femle Hth Temperture (T) Proility < < < < T < < < < xt : Vlues with ifferent letters (olumns) iffer signifintly (P < ). *ge given in hours fter the hnge in the inution temperture (ys of inution) femles h similr gluose levels t inution tempertures of 36 n 39 n lower levels t Hthing n mortlity rtes, eggshell onutne n egg mss loss: s shown in Tle 10, hthing rte ws highest n mortlity rte ws lowest for egg inution t 37.5, followe y inution t 36 n 39. Mortlity rte t n inution temperture of 39 ws 24.6% higher in 30-week-ol reeer eggs thn in 60-week-ol reeer eggs. oth eggshell onutne n egg mss loss inrese with inution temperture. DISUSSION The present stuy shows tht ontinuously high temperture uring the seon hlf of inution reue the hert growth in mles n femles hiks from 30-weeks-ol reeer eggs, using them ri hypoplsi t hthing, not oserve for hiks from 60-weeks-ol reeer eggs. lthough others uthors (Wineln et l., 2000; Leksrisompong et l., 2007) h reporte smller hert weight t high inution temperture, this effet reeer ge relte of the high inution temperture on this orgn is eing shown for the first time. Despite reue hert weight n somti inex in 30-week-ol reeer eggs (light eggs) h een reporte fter inution t high temperture, loo respirtory prmeters (R, HT, HG n MV) remine unhnge, initing tht fetuses i not respon with inrese in the hemtologil respirtory prmeters to higher oxygen emn tht result from the inrese in metoli rte promote y higher inution temperture. From the eginning of pulmonry respirtion t internl pipping, the influx of ir into the pulmonry system is greter ri emn thn previously experiene y the emryo uring inution. ri efiits uring this erly perio of pulmonry respirtion n negtively ffet the gs exhnge n n hve lee the 30- week-ol reeer eggs inute t 39 to present reue hthing suess whih i not reh 10% in the present stuy. ri efiits inrese the suseptiility of the ir to metoli iseses relte to riovsulr unerevelopment, suh s sites synrome (Luritz n MPherson, 1994; Leksrisompong et l., 2007). Thus, our t show tht the erese hert evelopment resulting from 766

7 Tle 10: Effets of inution temperture on hthing n mortlity rtes, eggshell onutne n egg mss loss in 30- n 40- weeks-ol reeer eggs 30 weeks ol 60 weeks ol Vriles P P Hthing rtes (%) < < Mortlity rtes (%) < < Eggshell onutne < < Mss loss (%) < < : Vlues with ifferent letters (olumns) iffer signifintly (P < ) inution t high temperture n preispose hiks n result from hepti glyolysis (rton et l., 1987) from 30-weeks-reeer eggs ut not hiks from ol whih n reue hepti growth n the heptosomti reeer eggs, to eveloping sites. inex (Dvis et l., 1988; rton et l., 1987). This We lso enountere tht tempertures ontinuously inites tht the inrese loo gluose levels n 1.5 lower or higher thn the stnr inution the reue liver weights reporte y the present stuy temperture h istint effets on eggs oy, liver n uner inution t tempertures 1.5 lower or higher hert weights n inexes, plsm gluose levels of thn usul t hthing re relte. The results of the mles n femles from 30- n 60-week-ol reeer present stuy re in greement with previous stuy in eggs. The oy weights of mles n femles from 30- whih emryoni tolerne to higher temperture ws week-ol reeer eggs were not influene y shown to e less thn tolerne to lower temperture inution temperture ut their hepti weights n (Wilson, 1991) n shoul e relte to inrese egg inexes erese inresing inution temperture weight loss. Signifint reutions in hthing suess n femles h higher gluose levels t 36 n 39 with inresing inution temperture from y 13 of n mles h higher gluose levels t 39 only. inution were lso oserve for roiler reeer eggs Differently, in 60-week-ol reeer eggs, mle weight y Givisiez et l. (2001) n for re-winge tinmou ws reue y high n low inution temperture, eggs y Nkge et l. (2003) n oleli n Queiroz while the femle weight ws reue y high inution (2012). temperture only n, in oth sexes, liver weight n Yet, oring to our results, in ll use inution hepti inex were lower t 36 n 39. t the sme times, femles h higher gluose levels t 36 n 39 thn t 37.5, wheres mles h higher gluose levels only t 39. onsiering tht, with isometril inreses in the size, volume inreses temperture, mles n femles from 30-w-ol n 60- w-ol mintine fetl evelopment hrterize y inrese in oy n orgn weights, plsm gluose levels n R, HT n HG vlues n y simultneous erese in MV vlues. This revels more rpily thn surfe re (Woos, 1999) n tht preserve pttern of fetl ontogeneti evelopment for the inrese in the eggshell onutne is not roiler, inepenent of inution temperture, sex n proportionl to inrese in fetl mss (Meijerhof n Vn reeer ge. These hnges in the loo respirtory eek, 1993), it is possile tht the lrger eggs hve n energeti prmeters n liver n hert weights greter iffiulty thn smller eggs to relize gs re onsistent with previous stuies of Morit et l. hnges with the ir of the inutor, minly t high (2009, 2010) n Tzw et l. (2011) for roilers n inution temperture n tht this h promote emus, respetively, uner usul inution temperture the reution in the hik weight from 60-weeks-ol t n they pper to e neessry to supply the inrese hthing, not oserve for hiks from 30-weeks ol oxygen n energy emns promote y metoli reeer eggs. Lower n higher temperture thn the inreses uring fetl growth in the seon hlf of usul inution temperture n slow or elerte inution (Nihelmn et l., 1998; Prizinger et l., emryoni evelopment, respetively (Romnoff, 1960; 1997). Lnster n Jones, 1988; Wilson, 1991; Lenro et l., 2004; Nkge et l., 2003; Morit et l., 2010) y hnging emryo growth, tissue metolism n onlusion: High temperture uring the seon hlf of respirtory rte. Inrese energy proution n the the inution perio preisposes hiks from light susequent inrese metolism our from y 10 of eggs ut not hiks from hevy eggs, to sites eggs inution in roiler n emu (Nihelmn et l., synrome fter hthing n hs ifferentil effets on 1998; Prizinger et l., 1997). Emryo exposure to high plsm gluose-levels n oy weight of mle n inution temperture uring the plteu phse of the femle hiks from light n hevy eggs. oxygen requirement mrkely stimultes growth n rohyrte metolism (hristensen et l., 1999). On the other hn, longer inutor perio lso rise longer perio of energeti emn. rohyrte moiliztion n hyperglyemi in response to stress KNOWLEDGEMENT The uthor re grteful to Função e mpro à Pesquis o Esto e São Pulo (FPESP, proess nº 2003/ ) for the grnts given to VSM. 767

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