02544naa a2200385 a 450000100080000000500110000800800410001902400370006010000190009724501000011626000090021652015190022565000180174465000120176265000220177465000140179665000150181065000140182565000170183965000170185665000100187365000200188365000170190365000120192065000100193265000120194265000240195465300170197870000190199570000210201470000180203570000200205370000190207377300660209215222692023-06-13 1993 bl uuuu u00u1 u #d7 a10.1095/biolreprod49.5.11332DOI1 aSCHRICK, F. N. aOvarian structures during the estrous cycle and early pregnancy in ewes.h[electronic resource] c1993 aAbstract: The development of ovarian follicular and luteal structures during the estrous cycle and early pregnancy in ewes was examined. Ewes were treated with prostaglandin F2 alpha to induce estrus; they were placed with either two fertile or two vasectomized rams and observed for estrus twice daily. Beginning at estrus (Day 0), ovaries were scanned for CL and for follicles > or = 2 mm by transrectal ultrasonography daily for the first 25 days of pregnancy (PREG, n = 17 ewes) or until Day 8 of the second estrous cycle (CYC, n = 15 ewes). Jugular blood samples were collected at ultrasonography and on Days 30, 35, and 40 of gestation for RIA of progesterone and estradiol-17 beta. Total follicles (17.6 +/- 1.3), number of follicles > or = 4 mm in diameter (11.3 +/- 0.6), and number of follicles that became the largest during the first 16 days of pregnancy or the first estrous cycle (4.9 +/- 0.3) did not differ between PREG and CYC ewes. Number of newly detected follicles each day and difference in mean diameter between the largest two follicles and all other follicles were similar between PREG and CYC ewes until luteal regression. At that time, difference in diameter between the largest two follicles and all other follicles increased in CYC ewes in parallel with estradiol-17 beta in serum. Mean concentrations of progesterone in serum were higher in PREG than in CYC ewes (2.4 +/- 0.1 vs. 2.0 +/- 0.1 ng/ml; p < 0.05) before onset of luteal regression, but mean areas of CL did not differ aCorpus luteum aFemales aOvarian follicles aOvulation aPhysiology aPregnancy aProgesterone aReproduction aSheep aUltrasonography aCiclo Estral aOvário aOvino aPrenhez aReprodução Animal aTime Factors1 aSURFACE, R. A.1 aPRITCHARD, J. Y.1 aDAILEY, R. A.1 aTOWNSEND, E. C.1 aINSKEEP, E. K. tBiology of Reproductiongv. 49, n. 5, p. 1133-1140, Nov 1993.