Serum and Milk Progesterone Monitoring and Its Relation to Ovarian Conditions in Egyptian Buffaloes

To investigate the correlation between ovarian structures and progesterone (P4) concentrations in Egyptian buffaloes (n=80), blood and milk samples were in association with gynecological examination. There was a positive correlation (r=0.38, P<0.005) between serum and milk P4 levels and the presence of CL resulted in an elevation of P4 (P<0.0001) as compared with smooth inactive ovary. The highest P4 levels were recorded with persistent CL, but the comparatively low levels were estimated during pregnancy. There was a substantial decrease in P4 with progression of pregnancy, but higher levels (P<0.05) were recorded at the 2 nd month. P4 levels in serum and milk were close at the 1st and 3rd months, while a gap between both levels was significant at the 2nd, 3rd and 5th months of pregnancy. In conclusion, P4 levels is an indicator to the reproductive status associated with presence of luteal tissue especially persistent CL in Egyptian buffaloes.