Influence of season and parity on embryo recovery and subsequent reproductive performances in early postpartum suckling Japanese Black cows

摘要

TheobjectiveofthisstudywastoevaluatetheeffectsofparityandseasonontheembryorecoveryandsubsequentreproductiveperformancesinearlypostpartumsucklingJapaneseBlackcows.Atotalof95cowsofdifferentparities(parity2-3:n=58;4-5:n=27;5:n=10)inspring(n=25),summer(n=18),autumn(n=38)andwinter(n=14)wereused.Bodyweightofcowsweremeasuredbeforeandaftercalving.Fortyor41daysaftercalving,cowsweresynchronizedwithcontrolledinternaldrugreleasedevice(CIDR),insertedfor7days.Aftertheonsetofestrus,cowswereartificiallyinseminated(AI)twiceandembryoswererecoverednon-surgicallyon7-8daysafterAI.Cowswhichproducedmorethanandlessthan5transferableembryoswerecategorizedasRankAandRankB,respectively.nbsp;Ahighernumberoffreezableembryoswereretrievedinparity4-5(P0.05).Significantlyhighernumberofembryoswereretrievedinwinterthaninspring,summerandautumn(P0.05).RankAcowshadsignificantlyhigherbodyweightbeforeandafterparturition,totalnumberofembryosandcorpusluteum(CL)thanRankBcows(P0.05).Inconclusion,parityandseasoninfluencedembryorecoveryinearlypostpartumsucklingJapaneseBlackcows.Cowshavinghighbodyweight,moreCLproducedgoodqualityofembryos.