Result of quantifying progesterone content in serum when inserting progesterone releasing device in vagina of ovariectomized cows

Abstract

Progesterone releasing intravaginal devices are being studied and produced in Viet Nam in order to replace the importing progesterone releasing intravaginal devices into the country. This is neccessary for developing the Vietnamese cattle herd in general and Vietnamese dairy cows in particular. In this study, 4 ovariectomized cows were used as the experimental materials. The experiment was conducted in two stages, in the first stage intravaginal device containing 1,3 g was used in 11 days and in the second stage intravaginal device containing 1,9g progesterone was used in 7 days. The control device was CIDR (New Zealand). The gap between the first and the second stage was 2 months. ELISA method was applied to determine plasma progesterone concentration for all the experimental cows. The studied result showed that the plasma progesterone concentration was rapidly increased in blood of cow after inserting the device, and this progesterone concentration was maintained at high level in the whole period of inserting device then returned rapidly to the initial level after removing the device (P<0,05). These results were similar with the result of the control one and there was no statistically different between the samples containing 1,9g progesterone and the samples containing 1,3g progesterone. In conclusion, the progesterone releasing intravaginal devices “made in Viet Nam” containing 1,3g or lower progesterone content will be farther studied in the near future.