126 riginal articles - dialnet · para ce no modelo 1 foi 0,02 na análise univariada e 0,02-0,03...

Rev Colomb Cienc Pecu 2017; 30:126-137

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Revista Colombiana de Ciencias Pecuarias

Original articles

Genetic evaluation of dystocia and its relationship with productive and reproductive traits in Holstein cows¤

Evaluación genética de distocia y su relación con las características productivas y reproductivas en vacas Holstein

Avaliação genética de distocia e sua relação com características produtivas e reprodutivas em vacas da raça Holandesa

Mohammad Hossein Salimi1, MSc; Navid Ghavi Hossein-Zadeh1*, PhD; Abdol Ahad Shadparvar1, PhD; Ali Reza Eghbal2, MSc.

1Department of Animal Science, Faculty of Agricultural Sciences, University of Guilan, Rasht, Iran.

2Animal Breeding Center of Iran, Karaj, Iran.

(Received: November 29, 2015; accepted: October 18, 2016)

doi: 10.17533/udea.rccp.v30n2a04

¤ Tocitethisarticle:SalimiMH,GhaviHossein-ZadehN,ShadparvarAA,EghbalAR.GeneticevaluationofdystociaanditsrelationshipwithproductiveandreproductivetraitsinHolsteincows.RevColombCiencPecu2017;30:126-137.

* Correspondingauthor:NavidGhaviHossein-Zadeh.DepartmentofAnimalScience,FacultyofAgriculturalSciences,UniversityofGuilan,Rasht,Iran.Tel.:+981333690274.Fax:+981333690281.E-mail:[email protected]

Abstract:

Background:dystociaisoneofthemosteconomicallysignificantsecondarytraitsindairycowsandhasadverseeffectsonthesubsequentsurvival,health,andperformanceofmothersandoffspring.Objective:theaimofthisstudywastoestimatedirectandmaternalgeneticparametersforcalvingease(CE)anditsrelationshipwithproductiveandreproductivetraitsinIranianHolsteincows.Methods:datafrom1991through2011werecollectedfromtheAnimalBreedingCenterofIran,andcontained132,831recordsofCE,183,203recordsofproductivetraitsincluding305-dadjustedmilkyield(MY305),305-dadjustedfatyield(FY305)and305-dadjustedproteinyield(PY305),and129,199recordsofreproductivetraitsincludingdaysopen(DO),daystofirstservice(DFS)andcalvinginterval(CI).Univariateandbivariatelinearanimalmodelswereusedfortheanalysisoftraitsintwodifferentmodelsonwhichdirectgeneticeffect(model1)anddirect+maternalgeneticeffects(model2)usingAI-REMLalgorithmwereincluded.Results:estimatedheritabilitiesforCEinmodel1were0.02inunivariateand0.02-0.03inbivariateanalyses.Directandmaternalheritabilitiesinmodel2were0.02and0.002forunivariate,and0.03and0.0004-0.006inbivariateanalyses,respectively.GeneticcorrelationsbetweendirecteffectsofCEwithMY305,FY305,andPY305were-0.99,0.02and-0.07inmodel1,and-0.2,-0.02and-0.13inmodel2,respectively.Conclusion:thisstudysuggestedthataselectionindexthatincludesbothdirectandmaternaleffectsshouldbeincludedinCEbreedingprograms.

Keywords: calving difficulty, dairy cow, genetic correlation, genetic parameters, productive performance.

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Salimi MH et al. Genetic evaluation of dystocia in cows

Resumen

Antecedentes: ladistociaesunodelosrasgossecundarioseconómicamentemássignificativosenlasvacaslecherasytieneefectosadversossobrelaposteriorsupervivencia,saludyelrendimientodelasmadresehijos.Objetivo:estimarparámetrosgenéticosdirectosymaternosparafacilidaddeparto(CE)ysurelaciónconlascaracterísticasproductivasyreproductivasenvacasHolsteiniraníes.Métodos:serecogierondatosdesde1991hasta2011enelCentrodeReproducciónAnimaldeIrán,quecontenían132.831registrosdelaCE,183.203registrosdecaracterísticasproductivas,incluyendo305-dajustadolaproduccióndeleche(MY305),305-dderendimientograsoajustado(FY305)y305-ddeproduccióndeproteínaajustada(PY305),y129.199registrosdecaracterísticasreproductivas, incluyendodíasabiertos (DO),díasalprimerservicio(DFS)yel intervaloentrepartos(CI).Seutilizaronmodelosanimaleslinealesunivariantesybivariantesparaelanálisisderasgosendosmodelosdiferentesenlosqueseincluyeronelefectogenéticodirecto(modelo1)ylosefectosgenéticosmaternosdirectos+(modelo2)usandoelalgoritmoAI-REML. Resultados:lasheredabilidadesestimadasparalaCEenelmodelo1fueron0,02enuniy0,02-0,03enlosanálisisbivariados.Lasheredabilidadesdirectasymaternasenelmodelo2fueron0,02y0,002paraunivariado,y0,03y0,0004a0,006enelanálisisbivariado,respectivamente.LascorrelacionesgenéticasentrelosefectosdirectosdelaCEconMY305,FY305yPY305fueron-0,99,0,02y-0,07enelmodelo1y-0,2,-0,02y-0,13enelmodelo2,respectivamente. Conclusión: esteestudiosugierequeuníndicedeselecciónqueincluyetantolosefectosdirectosymaternossedebeincluirenlosprogramasdemejoramientodelaCE.

Palabras clave: correlación genética, dificultad de parto, parámetros genéticos, rendimiento productivo, vaca lechera.

Resumo

Antecedentes:distociaéumadascaracterísticassecundáriaseconomicamentemaissignificativasemvacasleiteirasetemefeitosadversossobreasubsequentesobrevivência,saúdeedesempenhodemãesefilhos.Objetivo: oobjetivodesteestudofoiestimarparâmetrosgenéticosdiretoematernosparafacilidadedeparto(CE)esuarelaçãocomcaracterísticasprodutivasereprodutivasemvacasdaraçaHolandesairanianos.Métodos: dados de1991a2011foramcoletadosapartirdoCentrodeMelhoramentoAnimaldoIrã,estescontinham132.831registrosdaCE,183.203registrosdecaracterísticasprodutivas,incluindo305-drendimentoajustadoleite(P305),305-dproduçãodegorduraajustada(FY305)e305-drendimentoajustadoproteína(PY305),e129.199registrosdecaracterísticasreprodutivas,incluindojornadasdeportasabertas(DO),diasparaoprimeiroserviço(DFS)eintervaloentrepartos(CI).Modelosanimaislinearesunivariadosebivariadosforamutilizadosparaaanálisedecaracterísticasemdoismodelosdiferentesemqueforamincluídosefeitogenéticodireto(modelo1)eefeitosgenéticosmaternosdiretos+(modelo2)usandooalgorítmoAI-REML.Resultados: aherdabilidadeestimadaparaCEnomodelo1foi0,02naanáliseunivariadae0,02-0,03naanálisebivariada.Aherdabilidadediretaematernanomodelo2foi0,02e0,002paraunivariada,e0,03e0,0004-0,006nabivariada,respectivamente.AscorrelaçõesgenéticasentreosefeitosdiretosdaCEcomP305,FY305ePY305foram-0,99,0,02e-0,07nomodelo1e-0,2,-0,02e-0,13nomodelo2,respectivamente. Conclusão:esteestudosugerequeumíndicedeseleçãoqueincluaefeitosdiretosematernosdeveserincluídoemprogramasdemelhoramentoparaCE.

Palavras chave: correlação genética, desempenho produtivo, dificuldade de parto, parâmetros genéticos, vaca de leiteria.

Introduction

Calving ease is one of themost economicallysignificantsecondarytraits(DematawewaandBerger,1997), whichmeasures the presence or absenceof dystocia and its intensity. Dystocia, definedas a prolonged or difficult parturition, affects theprofitabilityofherds,animalwelfare,andacceptabilityoftheproductionsystembytheconsumer(Carnieret al.,2000).Notonlydoescalvingdifficultyincrease

farmworkload, it also has adverse effects on thesubsequent survival, health, and performance ofmothers and offspring (Dematawewa andBerger,1997;Lombardet al.,2007;Tenhagenet al.,2007;BarrierandHaskell2011).Calvingdifficultyimpairedmilkproductionofdairycowsintermsofcow’smilkproduction and saleablemilk yields, highlightingimpaired income for dairy producers aswell asdetrimentaleffectson theproductivityof thecows(BarrierandHaskell,2011).Dystociacannegatively

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affectreproductivetraits,suchasdaysopen(DO)ornumberofservicesperpregnancy(DematawewaandBerger,1997).Moreover,reproductiveperformanceofthedaminthefirstlactationworsenedfollowingadifficultcalving,withincreaseddaystofirstservice(DFS),numberofservicesneededtoconceiveandaprolongedCI (Eaglenet al.,2011).Calvingeaseis influenced by both direct andmaternal geneticeffects.Moststudieshaveshownanegativegeneticcorrelationbetweendirect andmaternaleffects fordystocia(LopezdeMaturanet al.,2007;Heringstadet al., 2007;Cevvantes et al., 2009; Eaglen andBijma,2009;MujibiandCrews,2009),whileothershavereportedapositivecorrelation(Wigganset al., 2003;Hansenet al.,2004).

Routine genetic evaluation of categorical traitssuchasfertilityandcalvingtraitsismostlybasedonlinearmodels.The Interbull guidelines (Interbull,2001) stated that an animalmodel is better thana siremodel and amultiple-traitmodel is betterthan a single-traitmodel.Genetic parameters havebeen estimated for dystocia (Abdullahpouret al., 2006;Eghbalsaiedet al.,2012),productive(GhaviHossein-Zadeh, 2011) and reproductive traits(Toghiani-Pozveh,2009;GhaviHossein-ZadehandArdalan,2010;GhaviHossein-Zadeh,2011;Ghiasiet al.,2011)inIranianHolsteincows.Nevertheless,theestimatesofgeneticcorrelationsbetweendystociaandperformancetraitswerescarceintheliterature.Therefore,theaimofthisstudywastoestimatedirectandmaternalgeneticparametersforcalvingease(CE)anditsrelationshipwithproductiveandreproductivetraitsinIranianHolsteincows.

Materials and methods

Data set

Dataconsistedof132,831firstparitycalvingease(CE)score,183,203recordsofproductionincluding305-dadjustedmilkyield(MY305),305-dadjustedfatyield(FY305)and305-dadjustedproteinyield(PY305),and129,199recordsofreproductivetraitsincludingdaystofirstservice(DFS),daysopen(DO)andcalvinginterval(CI)recordsfrom1,470herds.DatawerecollectedbytheAnimalBreedingCenterofIranfrom1991to2011.ThepedigreeinformationusedinthisstudywasextractedfromthedatabaseusedforthenationalgeneticevaluationofdairyherdsinIran,whichwasprovidedbytheAnimalBreedingCenterofIranandcontained1,267,754animalswith10,573sires.Calvingeasewasclassified into5categoriesdependingonparturition situation (1=normal,noproblem;2=slighthelp,minorproblem;3=neededassistance,majorproblem;4=considerableforce,mechanical or laborer’s assistance; 5= caesarean,very difficult). The distribution of CE scores issummarized inTable 1 separately by sex of calf.Approximately 25%of themale calveswere bornwithdifferentdegreesofdifficulty(scores2,3,4,and5)ascomparedtoonly18%forthefemalecalves.However, approximately 79%of calveswerebornwithoutdifficulty(score1).

For editingCEdata, animalswithout dystociascorewereremovedfromthedata.Also,calveswithunknownbirthweight, sex and typeof birthwereremoved.Finally,calveswithbirthweightlessthan

Table 1. Frequencies (%) of calving ease (CE) scores among male and female calves of heifers.

Total%Calving ease scoreCalf sex

54321

52,73039.70.11.79.313.875.1Male

80,10160.30.0250.7710.7581.525Female

1000.11.17.911.979%

132,831641,44810,51415,895104,910Total

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23or greater than57Kg, anddamwith gestationlengthoutsideof260-290dayswereexcluded.Forproduction traits, cowswere required to have aminimumof100daysinmilk(DIM)beforecullingandatleast1,000Kgoftotallactationmilkyieldtobeincludedintheanalysis.Forreproductivetraits,recordsoutsideof therange30-300daysforDFS,45-350daysforDOand300-600daysforCIwereexcluded.Foralldata,cowswithfirstcalvingbefore20monthsorafter40monthsofagewereexcluded,andatleast5uncensoredrecordswererequiredperherd-yeargroups.

Statistical analyses

Forallmodels,theGLMprocedureofSAS(SASInstituteInc.,Cary,NC,USA;2002)wasusedtoselectfixedfactorswhichhadsignificanteffectsonthetraitsunder study.Table2gives the informationoffixedeffectsfittedinthestatisticalmodelsofanalysis.Twodifferentunivariatemodelswereusedfortheanalysisofdatawhichweredifferedbyincludingdirectgeneticeffect(model1)anddirect+maternalgeneticeffects(model2).Linearanimalmodelswereused for theanalysisofCE(models1and2),productive(model1)andreproductive(model1)traits.

Model1:y=Xb+Zd d + e

Model2:y=Xb+Zd d + Zm m + e

Where:

y= is thevectorof observations forCE score,MY305,FY305,PY305,DFS,DO,orCI.

b=isthevectoroffixedeffects.

X,Zd and Zm = are incidencematrices linkingobservations tofixed, direct randomandmaternalrandomgeneticeffects,respectively.

d andm= are vectors of direct andmaternalgeneticeffects,respectively.

e=isthevectorofrandomresidualeffects.

Bivariatelinearanimalmodelswereusedfortheanalyses ofCE-MY305, CE-FY305, CE-PY305,CE-DFS,CE-DO,andCE-CI.Thebivariatemodelswereasfollows:

Where:

yi =isthevectorofCEscore.

yj = is the vector of observations forMY305,FY305,PY305,DFS,DO,orCI.

Xi and Xj = are incidence matrices linkingobservationstofixedeffects.

Zdi and Zdj = are incidencematrices linkingobservationstodirectrandomeffect.

bi and bj = are vectors of fixed effects forCEscoreandMY305,FY305,PY305,DFS,DO,orCI,respectively.

Zmi and Zmj = are incidencematrices linkingobservationstorandommaternalgeneticeffect.

di and dj =arevectorsofdirectgeneticeffects.

mi and mj=arevectorsofmaternalgeneticeffects.

ei and ej=arevectorsofrandomresidualeffects.Inmodel2,thevarianceswereasfollows:

Where:

A=istherelationshipmatrix.

I=istheidentitymatrix.

and =aredirectadditivevariancesforith and jthtraits,respectively.

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and =arematernaladditivevariancesforith and jthtraits,respectively.

=iscovariancebetweendirecteffectsofith and jthtraits.

=correspondstocovariancebetweendirectandmaternaleffectsofithtrait.

=correspondstocovariancebetweendirecteffectofithtraitandmaternaleffectofjthtrait.

=correspondstocovariancebetweendirecteffectofthejthtraitandmaternaleffectofithtrait.

=correspondstocovariancebetweendirectandmaternaleffectsofjthtrait.

= corresponds to covariance betweenmaternaleffectsoftheith and jthtraits.

and =arerandomresidualvariancesforith and jthtraits,respectively.

=correspondstocovariancebetweenrandomresidualeffectsofith and jthtraits.

Directandmaternalheritabilitieswerecomputedasfollows:

= , =

and 2 2 2 2p d m dm eσ σ σ σ σ= + + +

Where:

and =aredirectandmaternalheritabilities,respectively.

and = are direct andmaternal additivevariances,respectively.

σdm=iscovariancebetweendirectandmaternaleffects.

=israndomresidualvariance.

=isphenotypicvariance.

Geneticcorrelationsbetweendirectandmaternaleffectsofithtraitwereobtainedfrom

=

Geneticcorrelationsbetweendirecteffectsoftheith and jthtraitswereobtainedfrom

=

Geneticcorrelationsbetweendirecteffectsoftheithtraitandmaternaleffectsofjthtraitwereobtainedfrom:

=

(Co)variance componentswere estimatedusingAI-REMLalgorithmoftheMATVECprogram(Wanget al.,2001).

Table 2. Description of fixed effects affecting calving ease (CE), production, and reproduction traits.

Trait Fixed effects

Calving ease Sex of calf + calf weight + herd-year of calving + calving season + linear effect of

dam age + gestation length.

Production Herd-year of calving + calving season + linear effect of dam age + quadratic effect

of dam age.

Reproduction Herd-year of calving + calving season + linear effect of dam age.

Results

SummarystatisticsforproductiveandreproductivetraitsareshowninTable3.Also,estimatedvariancecomponentsandheritabilitiesforCEobtainedfromunivariateanalysisareshowninTable4.Heritabilityestimates forCEwere relatively small as 0.02 inModel1and,0.02and0.002fordirectandmaternalheritabilities inModel 2, respectively. Estimatedvariance components and heritabilitieswith theirstandarderrorsforMY305,FY305,PY305,DFS,DO,andCIobtainedfromunivariateanalysisareshowninTable5.TheheritabilityestimatesforDO,DFSandCIinModel1were0.04,0.03and0.04,respectively.

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Table 3. Summary statistics for 305-d adjusted milk yield (MY305), 305-d adjusted fat yield (FY305), 305-d adjusted protein yield (PY305), days open (DO), days to first service (DFS), and calving interval (CI) in Iranian Holsteins.

SDMeanMaxMinNTrait

1549.667596.713,8841297183,203MY305 (Kg)

57.13246.73476.8248.38183,203FY305 (Kg)

45.53233.5422.3150.83183,203PY305 (Kg)

6211634845129,199DO (day)

5910930030129,199DFS (day)

65405600300129,199CI (day)

N = number of observations; Min = minimum; Max = maximum; SD = standard deviation.

Heritability estimates obtained from bivariateanalysis for CE,MY305, FY305, PY305, DFS,DO,andCIarepresented inTable6.Estimatesofheritabilities forCE in the analyses ofCE-FY305andCE-PY305were0.03inModels1and2forbothanalyses.However,estimatesofheritabilitiesforCEintheanalysisofCE-MY305were0.001inModel1and0.03inModel2.MaternalheritabilityestimatesforCEinanalysesofCE-MY305,CE-FY305,andCE-PY305wereverylowas0.001,0.0004and0.0005inModel2,respectively.

Estimates of direct heritabilities forCE in theanalysesofCE-DO,CE-DFS,andCE-CIweresimilar(0.02)inModel1,and0.03fordirectgeneticeffectinModel2intheanalysisofCE-DO.Itisnoteworthy,analysisofCE-DFSandCE-CIinModel2didnot

converge.HeritabilityestimatesforMY305was0.34inModel1anddirectandmaternalheritabilitiesofMY305were0.25and0.008inModel2,respectively.HeritabilityestimatesforFY305were0.18inModel1and0.19and0.01fordirectandmaternalgeneticeffects,respectively,inModel2.HeritabilityestimatesforPY305were0.23inModel1and0.24and0.01fordirectandmaternalgeneticeffects inModel2,respectively.HeritabilityestimateforDOinModel1was 0.04 and direct andmaternal heritabilitieswere 0.04 and 0.0007 inModel 2, respectively.HeritabilityestimateforDFSwas0.03inModel1,butcorrespondinganalysesforModel2didnotconverge.HeritabilityestimateforCIwas0.03inModel1,butModel2didnotconverge.

Geneticcorrelationestimatebetweendirectandmaternal effects ofCE inmodel 2 obtained fromunivariateanalysis(Table4)was-0.41.Tables7and8showgeneticcorrelationestimatesbetweendirectandmaternaleffectsofCE,productiveandreproductivetraitsobtainedfrombivariateanalysis.EstimatesofgeneticcorrelationsbetweendirectandmaternaleffectsofCEatallanalysesinModel2includingCE-MY305,CE-FY305,CE-PY305, andCE-DOwere -0.38, -0.43, -0.45, and -0.36, respectively.Also, geneticcorrelation estimates between direct andmaternaleffectsofMY305,FY305,PY305,andDOinModel2werenegativeandmoderate.

Estimates of genetic correlations betweenCEandMY305inthisstudywerefavorableandhigh(-0.99) inModel 1, but low (-0.20) inModel 2for direct genetic effects. Estimates of geneticcorrelationsbetweenCEandFY305were0.02inModel1and -0.02 inModel2 fordirectgenetic

Table 4. Estimates of variance components, heritabilities (h2) and genetic correlation between direct and maternal effect (r) of calving ease (CE) obtained from univariate analysis.

(SE) (SE)

Model 1 0.0065 - - 0.313 0.319 - 0.02 (0.002) -

Model 2 0.0075 0.0007 -0.0009 0.317 0.324 -0.41 0.02 (0.003) 0.002 (0.001)

= direct additive variance. = maternal additive variance. = covariance between direct and maternal additive variance. = environmental

variance. = phenotypic variance. = genetic correlation between direct and maternal additive effects. = direct heritability. = maternal

heritability. SE = standard error (within brackets).

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Table 5. Estimates of variance components and direct heritabilities for 305-d adjusted milk yield (MY305), 305-d adjusted fat yield (FY305), 305-d adjusted protein yield (PY305), days open (DO), days to first service (DFS), and calving interval (CI) obtained from univariate animal model in Iranian Holsteins.

Trait (SE)

MY305 431,819 1,145,250 1,557,069 0.27 (0.005)

FY305 335.25 1445.61 1780.86 0.19 (0.005)

PY305 309.04 1012.49 1321.53 0.23 (0.005)

DO 126.03 3039.06 3165.09 0.04 (0.003)

DFS 89.47 2880.11 2969.58 0.03 (0.003)

CI 166.04 3858.85 4024.89 0.04 (0.003)

= direct additive variance. = environmental variance. = phenotypic variance. = direct heritability. SE = standard error (within brackets).

Table 6. Direct ( ) and maternal ( ) heritability estimates for calving ease (CE), 305-d adjusted milk yield (MY305), 305-d adjusted fat yield (FY305), 305-d adjusted protein yield (PY305), days open (DO), days to first service (DFS), and calving interval (CI; standard errors are within brackets) obtained from bivariate analysis in Iranian Holsteins.

Traits Model 1 Model 2

(SE) (SE) (SE)

CE - MY305 0.001 (0.0005) 0.03 (0.005) 0.001 (0.001)

0.34 (0.005) 0.25 (0.0075) 0.008 (0.004)

CE - FY305 0.03 (0.004) 0.03 (0.005) 0.0004 (0.0006)

0.18 (0.007) 0.19 (0.01) 0.01 (0.004)

CE - PY305 0.03 (0.004) 0.03 (0.005) 0.0005 (0.0006)

0.23 (0.01) 0.24 (0.01) 0.01 (0.004)

CE - DO 0.02 (0.004) 0.03 (0.005) 0.006 (0.004)

0.04 (0.005) 0.04 (0.006) 0.0007 (0.0003)

CE - DFS 0.02 (0.004) - -

0.03 (0.005) - -

CE - CI 0.02 (0.004) - -

0.03 (0.006) - -

effects.GeneticcorrelationsbetweenCEandPY305werefavorableandwere-0.07inModel1and-0.13inModel 2 for direct genetic effects. In addition,strong andpositive correlations estimatedbetweenmaternal genetic effect ofCE and direct geneticeffectsofMY305,FY305,andPY305 (0.83,0.67,and0.87,respectively).Geneticcorrelationestimates

betweenCEandreproductivetraitswereunfavorable,althoughtheywereverysmallinModels1and2fordirectgeneticeffects.ThecorrelationsbetweenCEwithDO,DFSandCIwere-0.05,-0.002and-0.06,inModel1,respectively,andwas-0.04betweenCEandDOfordirectgeneticeffectsinModel 2.

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Discussion

Ingeneral,theaveragesofDOandCIwerewithintherangeofvaluesreportedinsomestudies(Gonzalez-Recio andAlenda, 2005; Zink et al., 2011), theaverageofDFSinthecurrentstudywasgreaterthancorrespondingaveragesreportedbyotherresearchers(Andersen-Ranberget al.,2005;Sunet al.,2010;GhaviHossein-ZadehandArdalan,2010;Zinket al.,2011).TheunivariateestimatesofCEheritabilitywereslightlygreaterthanthosereportedbyAldayandUgarte(1997)andLeeet al.(2003)inHolsteins,andweresimilartoestimatesreportedbyNiskanenandJuga(2003)inAyrshiredairycowsfordirectheritability,andsmallerthan those reported byAbdullahpouret al. (2006)and Eghbalsaied et al. (2012) inHolsteins,Carnieret al.(2000)andAlberaet al.(2004)inPiemontese,Gutierrez(2006)inAsturianadelosVallesbeefcattle,andMujibiandCrews(2009)inCharolaisfordirectandmaternalheritabilities.Generally,theheritabilityestimatesforMY305,FY305,andPY305inModel1were in agreementwith those reportedbyGhaviHossein-Zadeh(2011)inIranianHolsteins.Estimatesofheritabilitiesforreproductivetraitsobtainedfrommodel1were in agreementwith those reportedbyGonzalez-RecioandAlenda(2005)andGredleret al. (2007)forDOandCI,andbyKoecket al.(2010)inAustrianFleckvieh (Simmental)dual-purposecattleforDFS.

The bivariate estimates of heritabilities forCEwere similar to estimates reported by Lee et al. (2003).TheheritabilityestimateobtainedinModel1was lower than the estimates obtained by otherresearchers, andwasmuch lower than expected,which can be affected by high levels of milk

Table 7. Genetic correlation estimates between calving ease (CE) and 305-d adjusted milk yield (MY305), 305-d adjusted fat yield (FY305), 305-d adjusted protein yield (PY305), days open (DO), days to first service (DFS), and calving interval (CI) obtained from bivariate analyses in Iranian Holsteins.

Traits Model 1 Model 2

Direct Direct Maternal

CE - MY305 -0.99 -0.20 -0.64

CE - FY305 0.02 -0.02 0.24

CE - PY305 -0.07 -0.13 -0.55

CE - DO -0.05 -0.04 -0.39

CE - DFS -0.002 - -

CE - CI -0.06 - -

Table 8. Genetic correlation estimates between direct (d) and maternal (m) effects of calving ease (CE) and 305-d adjusted milk yield (MY305), 305-d adjusted fat percent (FY305), 305-d adjusted protein percent (PY305), days open (DO), days to first service (DFS), and calving interval (CI) obtained from bivariate analyses in Iranian Holsteins.

Traits Model 2

Components Correlation

CE - MY305 CEd - CEm -0.38

MY305d - MY305m -0.15

CEd - MY305m 0.03

CEm - MY305d 0.83

CE - FY305 CEd - CEm -0.43

FY305d - FY305m -0.3

CEd - FY305m 0.06

CEm - FY305d 0.67

CE - PY305 CEd - CEm -0.45

PY305d - PY305m -0.35

CEd - PY305m 0.05

CEm - PY305d 0.87

CE - DO CEd - CEm -0.36

DOd - DOm -0.45

CEd - DOm -0.4

CEm - DOd 0.14

CEd = direct additive genetic effect of calving ease (CE). CEm = maternal additive genetic effect of calving ease (CE). MY305d = direct additive genetic effect of 305-d adjusted milk yield (MY305). MY305m = maternal additive genetic effect of 305-d adjusted milk yield (MY305). FY305d = direct additive genetic effect of 305-d adjusted fat yield (FY305). FY305m = maternal additive genetic effect of 305-d adjusted fat yield (FY305). PY305d = direct additive genetic effect of 305-d adjusted protein yield (PY305). PY305m = maternal additive genetic effect of 305-d adjusted protein yield (PY305). DOd = direct additive genetic effect of days open (DO). DOm = maternal additive genetic effect of days open (DO).

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productiondata.EstimatesofmaternalheritabilityforCEinModel2wereverylowerthanotherreports.EstimatesofdirectheritabilitiesforCEinbivariateanalysiswithreproductivetraitswereinagreementwiththosereportedbyNiskanenandJuga(2003)inFinnishAyrshire,AldayandUgarte(1997)inSpanishHolsteinsandLeeet al.(2003)inHolsteincowsofKorea.MaternalheritabilityestimatesforCEintheanalysisofCE-DOwas0.006whichwasagainlowerthanvaluesobtainedbyotherresearchers(AldayandUgarte,1997;Leeet al.,2003).Thisdifferencecouldbeduetodifferencesinthepopulationsunderstudyandthemodelused.Thelowestimateofheritabilityisduetolowestimateofgeneticvarianceandlargeamount of phenotypic variance.One reason couldbe due to the genetic differences between IranianHolsteinsandotherdairycattlepopulationsinothercountries.AnotherreasonwasrelatedtothemethodofrecordingdystociascoreandherdmanagementinIranwhichcanleadtoincreasingphenotypicvariance.Anothercauseof lowheritabilityestimatedforCEin this study thanof other studies,maybe relatedto differences in age of heifers in this studywithother studies. It seems thatwith increasing age ofdam,heritabilityestimateforthistraitwasreducedbecauseestimatesofheritabilitiesforCEinseveralstudiesforlaterparitiesweremuchlowerthanthoseinheifers(Luoet al.,2002;Lee,2002;Alberaet al., 2004;Erikssonet al.,2004).

EstimatesofheritabilitiesforMY305inModel1weresimilartotheestimatesreportedbyPerez-CabalandAlenda(2003),andinModel2byLeeet al.(2003),Gonzalez-Reeio et al. (2006) andGhaviHossein-Zadeh(2011).EstimatesofheritabilitiesforFY305obtainedfromModels1and2wereslightly lowerthanthosereportedbyLeeet al.(2003)andGhorbaniet al.(2011)inIranianBrownSwisscrossbreddairypopulation, and similar to estimate reported byGhaviHossein-Zadeh (2011).Direct heritabilitiesforPY305wereinagreementwiththosereportedbyGhaviHossein-Zadeh(2011),andwerelowerthantheestimatesreportedbyLopezdeMaturanaet al.(2007).Ofcourse,LopezdeMaturanaet al.(2007)obtainedestimatesusingtheBayesianmethod,whichcouldbeareasonforthedifferenceobserved.Generally,thedifferencesinparameterestimatescouldbeattributedtovariousfactorssuchaspopulationhistory,datasizeandstructure,themodelofanalysisused,breedand

environmentaleffects(Ilatsiaet al.,2007).However,maternaladditivegeneticeffectsofproductiontraitshavebeenignoredforgeneticevaluationinseveralcountriesbecauseoflittlecontributionoftheireffects.Otherwise, in the current study,maternal geneticeffectscouldcontribute3.1,5,and 4 percentagesoftotalheritabilitiesforMY305,FY305,andPY305,respectively. Thisresultshouldindicatethatadditivematernal genetic effectswere also important forgeneticevaluationofproductiontraits.

Direct heritability estimates for DOwere inagreementwiththosereportedbynumerousstudies(DematawewaandBerger,1998; Gonzalez-Recio and Alenda,2005;Gredleret al.,2007; Zinket al.,2011).Maternalheritabilityestimatesforreproductivetraitsarescarceintheliterature.However,accordingtotheestimatesobtainedinthisstudy,itappearsthataverysmallportionofthetotalheritabilityforreproductivetraitswasduetomaternal effects.EstimateofModel1 forDFSwas slightly lower than those reportedbyGonzalez-Recio andAlenda (2005), Liu et al. (2008)andGredleret al.(2007),andwassimilartothosereportedbyNeuenschwanderet al.(2005)andAndersen-Ranberg et al.(2005).However,estimateof heritability forCIwas consistentwith estimatereportedbyGredleret al.(2007),andwasneartothe0.04obtainedbyGonzález-RecioandAlenda(2005).Allheritabilityestimatesforreproductivetraitswerenear to the estimated ones obtained in univariateanalyses(Tables5and6),andwerelowerthanthosereportedbyToghianiPozvehet al.(2009),Ghiasiet al. (2011)indifferentparitiesofIranianHolsteins,andSunet al.(2010)inthefirstlactationofHolsteincowsinDenmark.However,estimatesofheritabilitiesfor reproductive traitswere generally lower than0.1(Kadarmideenet al.2003).Theseresultsareinagreementwithpreviousstudies.Thelowheritabilityestimatesforreproductivetraitsinthisstudyshowsthat these traits are toa largeextent influencedbyenvironmentalandotherherdmanagementpolicies.

Genetic correlation estimate between directandmaternal genetic effects ofCEobtained fromunivariate analysiswaswithin the range reportedinotherstudies(Carnieret al.,2000;Alberaet al., 2004). Bivariate estimates of genetic correlationbetweendirectandmaternalgeneticeffectsforCEwerelowerthantheestimatereportedbyLeeet al.

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(2003),whoreportedavalueequalto-0.63betweendirectandmaternaleffectsofCEusingmultipletraitanalysisofCE,MY305,FY305,andDO;however,inmoststudies,thiscorrelationwasnegative.ForCE,correspondingestimates indicated thatantagonisticrelationshipsexistbetweencalvingeaseasatraitofcalfandasatraitofthedamandthat,fromageneticpoint of view, female calves bornmore easily areexpectedtoexhibitgreaterdifficultieswhengivingbirth as dams (Lee et al., 2003). This negativecorrelationwouldreduceprogressfromselectingforreduceddystociaifonlydirecteffectswereconsidered(Thompsonet al.,1981).

Leeet al. (2003)andLopezdeMaturanaet al. (2007;withothermodels)foundanegativeestimatefor genetic correlation betweenCE andMY305.This result indicated thatCEwould influence lowmilkproductionatfirst parity.Although, estimatesofgeneticcorrelationsbetweenCEandFY305werenear tozero in thisstudy;however,our resultsareinagreementwiththeresultsreportedbyLeeet al. (2003).GeneticcorrelationsbetweenCEandPY305werereportedpositiveandclosetozerointhestudyofLopezdeMaturanaet al.(2007).Itisnecessarytopointoutthattheapplicationofothermethodologiesandmodelsinthosestudiesmighthaveaffectedtheresults.NegativegeneticcorrelationsbetweendirecteffectsofCEwithMY305andPY305 representareduction in animal production performance aftertheincidenceofdystocia.Leeet al.(2003)reportedpositivecorrelationsbetweenthematernaleffectofCEanddirecteffectsofMY305,andCEandFY305.

Given the negative correlation between directeffects ofCE and production traits, these resultsconfirmthenegativecorrelationbetweendirectandmaternaleffectsofdystocia;althoughpoorpositivecorrelationbetweendirectgeneticeffectofCEandmaternalgeneticeffectsofothertraitswasobserved.Leeet al. (2003) reported thatcorrelationbetweendirectgeneticeffectsofCEandDOintheabsenceofmaternaleffectswasnegative,butinthepresenceofmaternaleffectswaspositive.NegativecorrelationbetweendirecteffectsofCEandreproductivetraits,andpositivecorrelationbetweenmaternaleffectofCEanddirecteffectofDO,indicatingtheimportanceofmaternal effects of dystocia in order to obtainreproductiveprogress,atleastforDO.

TheheritabilitiesofCEandreproductivetraitswerelow,suggestinglowefficiencyofgeneticimprovementbydirect selection, and that these traits aremainlyinfluenced bymanagement practices and otherenvironmental factors. GeneticcorrelationestimatesbetweendirectandmaternaleffectsofCEinallmodelswerenegative and relativelyhigh, indicating that aselectionindexthatincludesbothdirectandmaternaleffects,mightbethemostefficientapproachtoincreaseCE.GeneticcorrelationsbetweendirecteffectsofCEwithFY305andfertilitytraitswereclosetozero,whilethiscorrelationwasnegativebetweenCEandMY305.Accordingtothecurrentresults,itisconcludedthatanimprovementinCEcanbeobtainedwhenselectionisfocusedonMY305only.

Acknowledgements

AuthorswishtoacknowledgetheAnimalBreedingCenterofIranforprovidingthedatausedinthisstudy.

Conflicts of interest

Theauthorsdeclaretheyhavenoconflictsofinterestwithregardtotheworkpresentedinthisreport.

ReferencesAbdullahpourR,Moradi-ShahrebabakM,Mehrabani-YeganehH,SayadnejadM,EghbalA.GeneticanalysisofdystociainHolsteincattleofIranbythresholdandlinearmodels.Proceedingsofthe8thWorldCongressonGeneticsAppliedtoLivestockProduction,BeloHorizonte,MinasGerais,Brazil22-24,2006.

AlberaA,GroenAF,CarnierP.Geneticrelationshipsbetweencalvingperformance andbeef production traits inPiemontesecattle.JAnimSci2004;82:3440-3446.

AldayS,UgarteE.GeneticevaluationofcalvingeaseinSpanishHolsteinpopulation.InterbullBull1997; 18:21-24.

AndersenRanbergIM,KlemetsdalG,HeringstadB,SteineT.Heritabilities,geneticcorrelationsandgeneticchangeforfemalefertilityandproteinyieldinNorwegiandairycattle.JDairySci2005;88:348-355.

BarrierAC,HaskellMJ.Calvingdifficulty in dairy cowshasa longer effect on saleablemilk yield thanon estimatedmilkproduction.JDairySci2001;94:1804-1812.

CarnierP,AlberaA,DalZottaR,GroenAF,BonaM,BittanteG.GeneticparametersfordirectandmaternalcalvingabilityoverparitiesinPiedmontesecattle.JAnimSci2000;78:2532-2539.

136



DematawewaCMB,Berger PJ. Effect of dystocia on yield,fertility,andcowlossesandaneconomicevaluationofdystociascoresforHolsteins.JDairySci1997;80:154-761.

EaglenSAE,BijmaP.GeneticparametersofdirectandmaternaleffectsforcalvingeaseinDutchHolstein-Friesiancattle.JDairySci2009;92:2229-2237.

Eaglen SAE,CoffeyMP,Woolliams JA,MrodeR,Wall E.PhenotypiceffectsofcalvingeaseonthesubsequentfertilityandmilkproductionofdamandcalfinUKHolstein-Friesianheifers.JDairySci2011;94:5413-5423.

EghbalsaiedS,AbdullahpourR,HonarvarM.Geneticevaluationforcalvingeasetraitusinglinearandthresholdmodelsinfirstparitydairycows.AfrJAgricRes2012;7(9):1395-1399.

Eriksson S,NäsholmA, JohanssonK, Philipsson J.Geneticparametersforcalvingdifficulty,stillbirth,andbirthweightforHereford andCharolais at first and later parities. JAnimSci2004;82:375-383.

GhaviHosseinZadehN,ArdalanM.GeneticrelationshipbetweenmilkureanitrogenandreproductiveperformanceinHolsteindairycows.Animal2010;5:26-32.

GhaviHosseinZadehN.Genetic parameters and trends forcalvingintervalinthefirstthreelactationsofIranianHolsteins.TropAnimHealthProd2011;43:1111-1115.

GhiasiH,PakdelA,NejatiJavaremiA,MehrabaniYeganehH,HonarvarM,GonzalezRecioO,CarabanoMJ,AlendaR.GeneticvariancecomponentsforfemalefertilityinIranianHolsteincows.LivestSci2011;139(3):277-280.

GhorbaniA,SalamatdoustNobarR,MehmanNavazU,GyasiJ,AgdamShahryarH,NazerAdlK.Heritabilityandrepeatabilityestimation in Iranian Brown Swiss crossbred dairy cattlepopulation.IntJAnimVetAdv2011;3(4):235-237.

GonzálezRecioO,AlendaR,ChangYM,WeigelKA,GianolaD.Selectionforfemalefertilityusingcensoredfertilitytraitsandinvestigationoftherelationshipwithmilkproduction.JDairySci2006;89:4438-4444.

GonzálezRecioO,AlendaR.Genetic parameters for femalefertilitytraitsandafertilityindexinSpanishdairycattle.JDairySci2005;88:3282-3289.

GredlerB,FuerstC,SolknerJ.Analysisofnewfertility traitsforthejointgeneticevaluationinAustriaandGermany.InterbullBull2007;37:152-155.

GutiérrezJP,GoyacheF,FernándezI,ÁlvarezI,RoyoLJ.Geneticrelationshipsamongcalvingease,calvinginterval,birthweight,andweaningweight in theAsturianade losVallesbeef cattlebreed.JAnimSci2007;85:69-75.

HansenM,LundMS,Pedersen J,ChristensenLG.Gestationlength inDanishHolstein hasweekgenetic associationswithstillbirth,calvingdifficulty,andcalfsize.LivestProdSci2004;93:23-33.

IlatsiaED,MuasyaTK,MuhuyiWB,KahiAK.Genetic andphenotypic parameters and annual trends formilk productionandfertilitytraitsoftheSahiwalcattleinsemiaridKenya.TropAnimHealthProd2007;39:37-48.

Interbull. Interbull guidelines for national and internationalgeneticevaluationsystemsindairycattlewithfocusonproductiontraits.InterbullBull2001;28.

JamrozikJ,FatehiJ,KistemakerGJ,SchaefferLR.Estimatesofgeneticparameters forCanadianHolstein female reproductivetraits.JDairySci2005;88:2199-2208.

KadarmideenHN,ThompsonR,CoffeyMP,KossaibatiMA.Geneticparametersandevaluationsfromsingle-andmultiple-traitanalysisofdairycowfertilityandmilkproduction.LivestProdSci2003;81:183-195.

KoeckA,EggerDannerC,FuerstC,ObritzhauserW,FuerstWaltB.Geneticanalysisofreproductivedisordersandtheirrelationshipto fertility andmilk yield inAustrianFleckviehdual-purposecows.JDairySci2010;93:2185-2194.

LeeDH.Estimationofgeneticparameters for calvingeasebyheifersandcowsusingmulti-traitthresholdanimalmodelswithBayesianapproach.Asian-AustJAnimSci2002;15(8):1085-1090.

LeeDH,HanKJ,ParkBH.Geneticrelationshipbetweenmilkyields,calvingeaseanddaysopenatfirstlactationofHolsteincowsinKorea.InterbullBull2003;31:122-129.

LiuZ, Jaitner J,Reinhardt F, PasmanE,Rensing S,ReentsR.Genetic evaluationof fertility traits of dairy cattle using amultiple-traitanimalmodel.JDairySci2008;91:4333-4343.

LombardJE,GarryFB,TomlinsonSM,GarberLP.Impactsofdystociaonhealthandsurvivalofdairycalves.JDairySci2007;90:1751-1760.

LopezdeMaturanaE,UgarteE,KomenJ,vanArendonkJAM.Consequences of selection for yield traits on calving easeperformance.JDairySci2007;90:2497-2505.

LuoMF,BoettcherPJ,SchaefferLR,DekkersJCM.EstimationofgeneticparametersofcalvingeaseinfirstandsecondparitiesofCanadianHolsteinsusingBayesianmethods.LivestProdSci2002;74:175-184.

MakgahlelaML,BangaCB,NorrisD,DzamaK,NgambiJW.Geneticanalysisofageatfirstcalvingandcalving interval inSouthAfricanHolstein cattle.Asian JAnimVetAdv 2008;3(4):197-205.

NeuenschwanderT,KadarmideenHN,WegmannS, deHaasY.Genetics of parity-dependant production increase and itsrelationshipwithhealth,fertility,longevityandconformationinSwissHolsteins. JDairySci2005;88:1540-1551.

NiskanenS, Juga J.Calving difficulties and calfmortality inFinnish cattle population, 1998, Proceedings InternationalWorkshoponGeneticImprovementofFunctionalTraitsinCattle,Grub,Germany,November1997.InterbullBull1998;18.

137



SAS.SASUser’sguidev.9.0:Statistics.SASInstitute,Inc,Cary,NC,USA;2002.

SunC,Madsen P, LundMS, ZhangY,NielsenUS, SuG.Improvement ingeneticevaluationof female fertility indairycattleusingmultiple-traitmodelsincludingmilkproductiontraits.JAnimSci2010;88:871-878.

TenhagenBA,HelmboldA,HeuwieserW.Effect of variousdegrees of dystocia in dairy cattle on calf viability, milkproduction,fertilityandculling.JVetMedSeriesPhysiolPatholClinicMed2007;54:98-102.

ThompsonJR,FreemanAE,BergerPJ.AgeofdamandmaternaleffectsfordystociainHolsteins.JDairySci1981;64:1603-1609.

Toghiani PozvehS, ShadparvarAA,Moradi ShahrbabakM,DadpasandTaromsariM.GeneticanalysisofreproductiontraitsandtheirrelationshipwithconformationtraitsinHolsteincows.LivestSci2009;125:84-87.

WangT,FernandoRI,KachmanDS.MATVECuser’s guide,DepartmentofBiometry,UniversityofNebraska,Lincoln2001.

WiggansGR,MisztalI,VanTassellCP.Calvingease(co)variancecomponentsforasire-maternalgrandsirethresholdmodel.JDairySci2003;86:1845-1848.

ZinkV,StípkováM,Lassen J.Geneticparameters for femalefertility,locomotion,bodyconditionscore,andlineartypetraitsinCzechHolsteincattle.JDairySci2011;94:5176-5182.

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