RESUMO
To study the progesterone concentration duringdifferent months of pregnancy in buffalo. Case control. Buffalo in different months of pregnancy blood samples were taken from 6 -8 herds ofbuffalo in different months of pregnancy. After preparingthe sera, progesterone concentrations measured by RIA. One - way ANOVA. The maximum and minimum concentrations ofprogesterone were in the second and tenth month ofgestation, respectively. Studing of the concentration of thishormone during the three period of gestation [early, middleand end] indicates that it's level is decreasing byprogressing of pregnancy. Different months of pregnancy canbe diagnosed by identification of progesteroneconcentrations, and the time close to parturation or evenparturation time can be identified by this method