بررسي رابطه حجم جسم زرد با غلظت پروژسترون سرم در گاو

Evaluation of the relationship between total volume of corpus luteum and serum progesterone concentration in cow

This study investigated the relationship between corpus luteum volume and serum progesterone concentration in cows. The data were obtained from 51 non-pregnant cows which were slaughtered in Ahvaz abattoir. Blood samples (10 ml) were collected from jugular vein prior to slaughter. After collection, blood samples were kept at room temperature for 3 hours, and then centrifuged for removal of the serum. Serum was stored at -20°C until progesterone was measured by radioimmunoassay. After the slaughter, the ovaries were recovered and CL sizes were recorded. The volume of each observed CL was determined using the principal components analysis and correlation between progesterone concentration and CL total volume was examined using regression analysis. Three cows had no CL and the mean (+SEM) progesterone concentration was 0.324+0.27ng/ml. Fourty eight cows had mature CL, and the mean total volume of CL was 1197.78+107.22mmʹ3 and the mean progesterone concentration was 1.583+0.22ng/ml. Progesterone concentrations in 20 cows were more than 1.5ng/ml (mean 2.948+0.38 ng/ml) with a mean CL volume of 1760.77+124.30mm\ while in the other 28 cows they were less than 1.5ng/ml (mean 0.55+0.08 ng/ml) with a mean CL volume of 795.65+110.30mm3. Correlation between corpus luteum total volume and progesterone concentration was significant (P<0.01), so that with every mmʹ1 increment on total volume, progesterone concentration increased by 0.0016 and 0.0005 ng/ml in cows with active and inactive corpus luteum, respectively.