Effect of exogenous melatonin on sexual behaviours in West African Dwarf goat

摘要

TwotrialswereconductedtoinvestigatetheeffectofexogenousmelatoninonsexualbehavioursofWestAfricanDwarf(WAD)goats.ThirtytwoWADgoats(20doesand12bucks)wereused.Doeswereadministereddosesofmelatoninat0,3,6and9mg.Inthesecondtrial,buckswereadministereddosesofmelatoninat0,3,6and9mg.Melatoninwasadministeredorallyfortenconsecutivedays.Oestrusresponse(P0.05)was40,60,100and80%forthe0,3,6,and9mgmelatoninrespectively.Doesinducedwith6mgmelatoninhadshorterinterval(22.0#177;0.22days)betweentreatmentterminationandonsetofoestruscomparedto0(24.5#177;0.5days),3(25.0#177;0.98days),and9mgmelatonin(23.5#177;0.74days).Similarly,doesinducedwith6mgmelatoninhadlongerdurationofoestrus(58.6#177;1.49hrs)comparedto0(54.0#177;1.19hrs),3(55.0#177;0.99hrs)and9mgmelatonin(58.0#177;1.16hrs).Inaddition,doesinducedwith6mgmelatoninhadhigher(P0.05)serumoestrogenconcentration(25.36#177;11.46pg/ml)comparedto6.98#177;4.93pg/ml,23.77#177;6.77pg/mland16.94#177;0.89pg/mlfor0,3and9mgmelatoninrespectively.Sexualbehavioursofbucksshowedincreased(P0.05)fullerectionwith6mgmelatonin(2.0+0.4)comparedto0(0.66+0.2),3(1.66+0.28)and9mgmelatonin(1.33+0.2).ThefindingsofthisstudyindicatethattreatmentofWADdoeswith6mgmelatoninresultedinatwoandhalf-foldincreaseinthedoesthatcameonheat.Similarly,treatmentofbuckswith6mgmelatoninimprovedsexualbehaviourinWADbucks.