Effect of Body Condition Score and Parity on Resumption of Postpartum Ovarian Activity in Montberliard Dairy Cows in Algerian Semi -Arid Area

Abstract

A study was undertaken to evaluate the relationships between body condition score (BCS), parity and serum hormonal profiles (progesterone (P4) and estradiol -17β (E2)), and resumption of postpartum ovarian cyclicity on (primiparous (n=19) and multiparous (n=59) Montbeliard cows. The BCS was measured at calving, using a 1 to 5 point scale according to the Edmonson (1989) method. Blood samples were collected by jugular venous at 30 d, 40 d, 50 d and 60 d postpartum (10 days of interval). Serum hormonal analysis were determined by chimiluminescent Immuno-Assay (CLIA). Changes in progesterone concentration were exploited to assess the resumption of ovarian cyclicity. The results showed a significant increase in progesterone and estradiol -17β serum levels during postpartum period. The correlation analysis showed that P4concentration in cows was positively correlated with their BCS at 30 d, 40 d, 50 d and 60 d postpartum (r =0.630; r = 0.603; r = 0.622 and r = 0.467 respectively; P<0.01). Additionally, the BCS at calving was positively correlated with estradiol -17β concentration at 30 d (r= 0.628); 40 d (r= 0.612); 50 d (r= 0.444) and 60 d (r=0.294) (P<0.01). Furthermore, BCS at calving was strongly but negatively correlated with CCI (r= 0.704; P<0.01). The results of the current study provide an evidence of a negative correlation between calving conception interval and secretion of P4 and E2.