摘要：Background and Objective: Reproductive rate is a major factor contributing to the efficiency of milk and meat production. Genetic, environmental and physiological factors can affect the reproductive efficiency of goat. This research aimed to determine levels of the progesterone and blood profiles from Ettawa-Saanen crossbreed goats in Indonesia during normal oestrus cycle. Materials and Methods: Eight Ettawa-Saanen crossbreed goats ( Capra hircus ) with Body Score Condotion (BCS) 2-3, known the cycle and the oestrus detection were studied by vaginal smear methods. Investigations were done by comparing progesterone levels and biochemical blood profiles of goats with natural oestrus cycles and goats with oestrus synchronization. Blood samples were collected from the jugular vein on days 0, 3, 12 and 15 of oestrus as the representative sample of each phase of the oestrus cycle. Progesterone concentration in the blood was determined using enzyme-linked immune sorbent assay and the biochemical blood serum profile was measured using spectrophotometry. Values obtained were expressed as Mean±SEM and were subjected to one-way analysis of variance (ANOVA) followed by SPSS version 16.0. Results: The serum progesterone level of crossbreed goats was significantly higher (p 1 on day-0 to 0.084±0.11 on day-3 and reached the peak value of 0.23±0.11 on day-12, which was maintained until day-15. The biochemical blood serum profile (glucose, albumin, cholesterol and blood urea nitrogen levels; p>0.05) showed no significant difference in each phase of the oestrus cycle. Conclusion: It was concluded that the progesterone level was significantly different in each phase of the oestrus cycle and peaked during the dioestrus phase.
