ThanhN.V., HangP.T., GioiP.V., ToanN.C. and LongS.T. 2023. The Relationship Between Plasma Progesterone Concentration on Day 6 After Artificial Insemination and Pregnancy Rate of Dairy Cows in Vietnam. Tropical Animal Science Journal. 46, 2 (May 2023), 146-150. DOI:https://doi.org/10.5398/tasj.2023.46.2.146.