Correlation between plasma progesterone concentrations and fecal Progestins during the estrus cycle of Kedah Kelantan cows

Abstract

The aim of the present study was to determine the correlation between circulating plasma progesterone (P4) levels and feacal progestins during the estrus cycle of Kedah Kelantan (KK)cows. A total of 12 KK cows pre-synchronized for estrus were subjected to blood and matched fecal sampling twice a week for about 3 cycles. The concentration of progesterone in the plasma and progestins in the fecal samples were determined by using a commercial progesterone radioimmunoassay (RIA) kit (ACTIVE® Progesterone RIA, DSL-3900, USA). A significant positive correlation between the concentrations of fecal progestins and plasma P4 was observed (r = 0.66, p<0.001), as tested for the whole group with the exception of one animal. This implies that the non- invasive measure of fecal progestins using a DSL-3900 RIA kit can be used to monitor the ovarian activity of KK cows. Furthermore, this technique might have also a potential application in monitoring the reproductive activity of captive and free ranging wild life ruminants.