Background: The role of Muscovy ducks in industrial poultry production is gaining importance; however, their reproductive physiology remains poorly understood. This study examines changes in reproductive performance in female Muscovy ducks (Cairina moschata forma domestica) by analyzing estradiol-17β and progesterone levels along with detailed anatomical examinations of the oviduct. Thirty-five young female ducks emerged together, each hatched after a synchronized incubation period of thirty-five days, were randomly divided into groups and housed in outdoor aviaries. Each aviary was equipped with a feeding trough, a water container, and a nesting box. The ducks were artificially hatched under controlled conditions. At the outset of the experiment, the ducks exhibited no laying activity. Within the investigation, the serum estradiol-17β and progesterone levels, along with the macroscopic and microscopic structure of the oviduct, were evaluated. Results: Ducks were euthanized at various intervals after laying their 1st, 2nd, 4th, 6th, 10th, 15th, and 20th eggs. Analyses focused on endocrine status and the anatomical structure of the oviducts. Results indicate that the serum concentrations of Estradiol-17ß and Progesterone progressively increase as the transition into the laying period occurs, reaching their peak during the laying phase. However, upon transitioning to the brooding period, hormone levels in the blood serum notably decrease. Oviduct length varied significantly throughout the reproductive cycle, with a mean of 107 ± 9 mm (SD) in juveniles. It peaked at a mean of 632 ± 58 mm (SD) after the tenth egg and then declined to a mean of 235 ± 87 mm (SD) by the 35th day of brooding. Conclusion: This study provides detailed information on the reproductive physiology of Muscovy ducks, highlighting the significant hormonal and anatomical changes that occur throughout their reproductive cycle. © The Author(s) 2025.
