Effects of flushing with two energy levels on goat reproductive performance

摘要

nbsp;Theobjectiveofthisstudywastoevaluatetheeffectsofsupplementationwithtwoconcentratelevels(CL)onbodyconditionscore(BCS),andbodyweight(BW)ofbreedinggoats,numberofkidsborn,birthandweaningweight,andrateofweightgainoftheoffspring.TreatmentswereahighCL(600g/dofgrainmix;1.8McalME)andalowCL(300g/d;0.9McalME)inacompletelyrandomizeddesign.Sixnannies(BW=38.5kg,BCS=2.8)wererandomlyassignedtoeachtreatment.Thegoatsgrazednativegrasspastures.Flushingstarted21-dpriortointroductionofthebuckandcontinuedfor42-d.Thereafter,allnannieswerefedalowCLuntilparturition.Nannieswereweighedatthestartofflushing,andat9and96daysafterintroductionofthebuck.BCSwasestimatedmonthly.Thekidswereweighedatbirthandweeklyuntilweaning(45days).nbsp;TherewerenoeffectsofCL(P0.05)onBW,BCS,andkidnumbers,but,kidbirthweightwaslowerwiththehighcomparedtothelowCL(2.5vs.3.3kg).ThiswasaresultofmoretwinningwiththehighCL.Therewasalsonoeffect(p0.05)ofCLonweaningweight(8.2vs.7.8kg)andweeklyrateofweightgain(860vs.727g)withthehighandlowCL,respectively.nbsp;Inconclusion,CLgreaterthan300g/dpriortoandduringthematingseasondidnotimprovereproductiveperformanceinmeatgoats.However,similarstudiesconductedinnannieswithlowerinitialBCSthanthoseofthepresentexperimentorwithmoreanimalspertreatmentmightshowabenefitofthehighersupplementationlevel.