Abstract
Serum cholesterol levels were examined during two consecutive estrous cycles in female beagles. Estrogen and progesterone were also measured simultaneously. In addition, phospholipid, triglyceride and free fatty acid were measured. The peak levels of total cholesterol were 226±25 mg/100 ml at 5.3±0.5 weeks during the first estrus and 234±20 mg/100 ml at 4.8±1.0 weeks during the second estrus. The peak levels of 17β-estradiol and progesterone were 33.0±7.8 pg/ml at just after estrus and 18.7±1.6 ng/ml 2.0±1.0 weeks after the estrus, respectively. The changes in progesterone after estrus resembled those of serum cholesterol after estrus. The increase of phospholipid levels occurred slightly later and was more moderate than that of cholesterol levels. Triglyceride levels tended to be slightly higher at estrus and after several weeks of estrus, but free fatty acid did not changc during estrous cycle in the female beagle.
