Fig 1: IGF-1 levels change in the blood of multiparous and primiparous dairy cows at different times after parturition. Cows were assigned into either multiparous group (multiparous dairy cows, n = 32) or primiparous group (primiparous dairy cows, n = 32). The concentrations of Estradiol were detected by ELISA method at 5, 10, 15, 20, 30, and 40 days after parturition in both multiparous and primiparous dairy cows.