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1、CloneFarm【克隆农场】Factoryfarmingcouldsoonenteraneweraofmassproduction.CompaniesintheUSaredevelopingthetechnologyneededto“clone”chickensonamassivescale.Onceachickenwithdesirabletraitshasbeenbredorgeneticallyengineered,tensofthousandsofeggs,whichwillhatchintoidenticalco
2、pies,couldrollofftheproductionlineseveryhour.Billionsofclonescouldbeproducedeachyeartosupplychickenfarmswithbirdsthatallgrowatthesamerate,havethesameamountofmeatandtastethesame.This,atleast,isthevisionoftheUS’sNationalInstituteofScienceandTechnology,whichhasgivenOr
3、igenTherapeuticsofBurlingame,California,andEmbrexofNorthCarolina$4.7milliontohelpfundresearch.Theprospecthasalarmedanimalwelfaregroups,whofearitcouldincreasethesufferingoffarmbirds.That’sunlikelytoputoffthepoultryindustry,however,whichwantsdiseaseresistantbirdsthat
4、growfasteronlessfood.“Producerswouldlikethesamemeatquantitybuttousereducedinputstogetthere,”saysMikeFitzgeraldofOrigen.Tomeetthisdemand,Origenaimsto“createananimalthatiseffectivelyaclone”,hesays.Normalcloningdoesn’tworkinbirdsbecauseeggscan’tberemovedandimplanted,I
5、nstead,thecompanyistryingtobulk-growembryonicstemcellstakenfromfertilizedeggsassoonasthey’relaid.“Thetrickistoculturethecellswithoutthemstartingtodistinguish,sotheyremainpluripotent,”saysFitzgerald.Usingalong-establishedtechnique,thesedonorcellswillthenbeinjectedin
6、totheembryoofafreshlylaid,fertilizedrecipientegg,formingachickthatisa“chimera”.Strictlyspeakingachimeraisn’taclone,becauseitcontainscellsfrombothdonorandrecipient.ButFitzgeraldsaysitwillbeenoughif,say,95percentofachicken’sbodydevelopsfromdonorcells.“Inthepoultrywor
7、ld,itdoesn’tmatterifit’snot100percent,”hesays.AnotherchallengeforOrigenistoscaleupproduction.Todothis,ithasteamedupwithEmbrex,whichproducesmachinesthatcaninjectvaccinesintoupto50,000eggsanhour.Embrexisnowtryingtomodifythemachinestolocatetheembryoandinjectthecellsin
8、topreciselytherightspotwithoutkillingit.Infuture,Origenimaginesfreezingstemcellsfromdifferentstrainsofchicken.Iforderscomeinforaparticularstrain,
