بررسي ارتباط سطوح اوره خون با غلظت استراد پول و پروژسترون در گاوهاي شيري

The Relation of Serum Urea Nitrogen with Stradiol and Progesterone Levels in Lactating Cows

This study was conducted to: 1) investigate the relationships between scrum urea nitrogen concentrations (SUN) and serum steroid hormones concentrations and 2) relate SUN to pregnancy in dairy cows. Blood samples were collected at the day of insemination from 75 lactating cows of a dairy farm, which came into heat during a 4 weeks period. Forty-Five days after insemination, cows were determined to be either pregnant or non-pregnant. Average SUN concentrations of non-pregnant cows were significantly higher than those of pregnant cows (p<0.05). There were no significant differences between mean estradiol and progesterone concentrations of pregnant and non-pregnant cows. Also, based on SUN mean (15 mg/dl), cows were divided into two groups: 1- cows with SUN concentrations less than mean and 2- cows with SUN concentrations greater than mean. Progesterone concentrations between these groups were not significantly different. However, mean estradiol concentration of group 1 was significantly greater than those of group 2 (p