Relationship between Blood Glucose and Insulin Levels with Ovarian Activity Onset in Dual Purpose Cows with different Body Condition Score at Calving and different Postpartum Food Level
Pinto-Santini, L.; Drescher, K.; Ruiz, A.; Perez, R.; Dominguez, C.; Benezra, M.; Martinez, N.
Interciencia 34(5): 350-355
The effect of body condition (CC) at parturition and feeding level (A) during the postpartum period (PP) on glucose concentration and PP insulin, as well as the resumption of ovarian activity in dual purpose cows, was evaluated. Twenty-eight adult cows were randomly allocated to four different treatments, ACAA: high CC (AC >= 2.5) at parturition and high A PP (AA); BCAA: low CC (BC<2.5) at parturition and AA; ACBA: AC and low A PP (BA); BCBA: BC and BA. A during PP did not affect the variables studied. The accumulated glucose levels at 45 days PP were 239.4 and 262.6mg.dl(-1) (P = 0.083) and those of insuline were 34.21 and 19.391 mu IU.mg(-1) (P<0.01) for cows with AC and BC, respectively. Either the CC at parturition or the A PP did not exert any effect on class 1 (C1) and 2 (C2) follicle population. In contrast, the CC at parturition ciftected (P<0.01) class 3 follicles (C3) and number of corpora lutea (CL). Thus, cows with AC showed both higher C3 follicle populations and CL, when compared to cows with BC. This work confirms that CC at parturition is a determinant factor in the resumption of AO in dual purpose crossbred cows.