Cabergoline,an ergot alkaloid is an agonist of dopamine receptors and inhibits prolactin secretion.This study investigated the effects of different doses of cabergoline (0,50,and 100 μg/kg) given by daily gavage for 3 days on the behavioral characteristics and physiological states of adult female lesser rice-field rats,Rattus losea (n=8 per group) .Animals were killed at 7 and 24 days after the end of treatment.We measured serum estrogen (E2) ,progesterone (P) ,prolactin (PRL) and reproductive organ mass,and observed their inter-sexual or intra-sexual social behavior before tissue collection.Cabergoline treatment did not significantly affect ovarian and uterine mass.In females treated with 50 μg/kg of cabergoline,serum E2,but not serum P,increased significantly at day 7 compared with the control group.Over time,both cabergoline doses significantly reduced serum PRL by 56%and 57%respectively at day 24 compared with the control and day 7 groups.The duration of individual investigation by treated animals (50 μg/kg) of control females was longer than for untreated female pairs.However,the duration of self-grooming and resting decreased significantly.The duration of female investigation and defense towards untreated adult males was lower in the 50 μg/kg group at day 24 compared with the untreated group.Our data showed that cabergoline treatment affects PRL and E2 levels in female R.losea depending on dose and time after treatment.Furthermore,the behavioral data in our experiment suggested that cabergoline treatment can significantly disturb the inter-or intra-sexual social behavior of female R.losea.