The efficiency of medroxyprogesterone acetate (MAP) and fluorogestone acetate (FGA) sponges with or without PGF(2alpha) (cloprostenol) for synchronizing estrous in non-lactating does was investigated during the natural breeding season. Does were treated for 11 days with 60 mg MAP (n = 38) or 40 mg FGA (n = 32) sponges. All does also received intramuscular injections of 500 IU PMSG. In addition, 19 and 14 of the does synchronized with MAP and FGA respectively, were injected with 125 mug cloprostenol and the remaining does from both groups were injected with 1.5 ml of sterile saline solution, 48 h prior the sponge removal. Cervical artificial insemination (AI) with diluted fresh semen was performed at a fixed time (36 and 48 h) following progestagen withdrawal. The different groups estrous response for the first 12 6 h and within 66 h, time to onset and duration of the induced estrous, and pregnancy rate was found to be 52.6%, 92.9%, 20.6 +/- 0.8 h, 29.7 +/- 1.3 h, and 70.0%, respectively. There were significant differences between groups FGA/PMSG/PGF(2alpha) and MAP/PMSG in terms of the duration of induced estrous (P < 0.05) and between groups FGA/PMSG/PGF(2alpha) and FGA/PMSG in terms of estrous response at the first 12 +/- 6 h (P < 0.05). These results indicate that, the use of MAP/PMSG and FGA/PMSG intravaginal progestagen treatments with or without cloprostenol are equally efficient in synchronizing estrous in non-lactating hair goats during the natural breeding season.