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1、LivestockProductionScience78(2002)6370www.elsevier.com/locate/livprodsciVariationofpigletsbirthweightandconsequencesonsubsequentperformanceN.Quinioua,*,J.Dagorn,D.Gaudrea´baInstitutTechniqueduPorc,BP3,35590LeRheu,FrancebStationdExperimentationNationalePorcin
2、e´´,routedeMiniac/Becherel,35850Romille´,FranceAbstractDatacollectedfrom965littersfromthestartofthePigResearchStationofITPinJuly1998untilOctober2000(12,041pigletsborn)wereusedtoevaluatethevariationofpigletsbirthweightanditsconsequencesonpost-weaningperforman
3、ce.Allpigletswereindividuallyweighedatbirthandat27daysofage(weaning)butonlysomeofthemwerestudiedafterweaning.Increasinglittersizefrom#11to$16pigletsresultsinareducedmeanbirthweightfrom1.59to1.26kg,whichcorrespondstoameandecreaseof35gpereachadditionalpigletbo
4、rn.Concomitantly,theproportionofsmallpiglets,i.e.weighinglessthan1kg,increasesfrom7to23%oftotalbornintheselitters.Below1.0kgBW,morethan11%ofpigletsarestillbirthsandthereaftermorethan17%diewithinthefirst24h.Thecorrespondingvaluesabove1.0kgaverage4and3%,respect
5、ively.Despitealownumberofsmallanimalsstillaliveatweaning,ourdataindicatethatthehigheristhebirthweightthehigheristheaveragedailygainbothoverthesucking,thepost-weaningandthegrowingfinishingperiods.Ó2002ElsevierScienceB.V.Allrightsreserved.Keywords:Piglet;Birthw
6、eight;Survival;Growthperformance1.Introductionprecisely,increasedmortalitymaybeattributedtotheincreasedproportionofpigletsoflowBW.Overthelastdecade,selectionforimprovedIndeed,lowBWpigshavealowlevelofbodyprolificacyhasresultedinanimportantincreaseofenergystore
7、,whichresultsinahighersensitivitytolittersizeatbirthandatweaning.However,thecold,theyhaveadelayedfirstsuckleandpresentaimprovementatbirthisnotcompletelyrecoveredatlowerabilitytogetthebestteats(LeDividich,weaningasitisassociatedwithahigheroccurrence1999).There
8、sultingloweramountofcolostrumandofbothperi-andpost-natalmortality(Gueblezand´milkintakeisassociatedwithapooreracquisitionofDagorn,2000).Theselossescanbepartlyrelatedtopassiveimmunityandalownutri
