Relationships between ano-genital distance, parity and some reproductive parameters in rabbits

摘要

Nulliparous(n=16)andprimiparousrabbitdoes(n=21),housedinindividualcages,werethesubjectofanexperimenttostudytheeffectofAno-GenitalDistance(AGD)onsomecharacteristicsofreproduction(sexualbehavior,reproductiveperformancesandthemainbiologicalcomponentsoflittersize).Theobservationsontheanimalsfocusedon,atfirst,onthelengthoftheAGD,thenumberofteats,thereceptivity,thechinmarkingandthefemalebehaviortowardsthemale.Subsequently,diagnosedpregnantfemalesweresacrificedonday12ofgestationtoobservethecharacteristicsoftheovaries(weightandnumberofpreovulatoryfollicles)andbiologicalcomponentsoflittersize(ovulationrateandembryonicmortality).AGDmeasuredwas20.9±2.0mm;18rabbitswithsmallAGD(belowaverage)and19withlargeAGDweredistinguished.Theresultsshowedthatthefemaleparityappearstohaveaneffectonalargenumberofcharacteristicsofreproduction.IthadasignificanteffectontheAGD:nulliparousfemalesshowedahigherAGDthanthatmeasuredinprimiparousfemales(p0.05),otherwise,thesefemalesmarkedmoretheirterritory,hadafertilityrateandanearlymortalitysignificantlyhigherandalowerlatemortalitythantheprimiparousones.TheAGDinturn,affectedatleastaggression,chinmarking,receptivityandembryonicmortality.InfemaleswithlargeAGD,comparedtothosewiththesmallAGD,thespontaneouschinmarkingwassignificantlyhigher,aggressivenesswasmoreimportant,thereceptivityrateswereonaverage,greaterandtheovarianweightwassignificantlyhigher;however,theearlyandlatemortalityweresignificantlyhigher.