Goats from 2-5 years old in 15 herds of four breeds, (Saanen, Nubian, Toggenburg and Alpine), were used in three experiments to determine reproductive behaviour (Experiment 1), metabolic profile (Experiment 2) and fertility of induced and synchronized oestrus (Experiment 3). Season, breed and physiological status were significant factors affecting reproductive behaviour and metabolic status (P<0.05). The principal causes of infertility in induced oestrus were failures in conception, early embryonic mortality and anovulatory oestrus. The herds had long intervals from birth to first insemination (306-458 days) and to first pregnancy (471-511 days), and low fertility (14-31%). The breeding patter was similar to breeds in temperate zones. Energy and mineral imbalances were found. Further research is necessary to improve reproductive performance of these breeds under tropical conditions. (author). 25 refs, 3 figs, 4 tabs.