The level of P4 at the time of embryo transfer (ET) is important. P4 concentrations and numbers of corpora lutea for 126 recipients were evaluated. Nuclear transfer embryos were transferred into 126 surrogates. 11 maintained their pregnancy until full-term delivery, 17 miscarried, and implantation failed in 98 animals. P4 levels in the full-term group were significantly different from those of ...

The histologic appearance of the ovaries and persistence of corpora lutea vary considerably among domestic animals, particularly between spontaneous and induced ovulators. The seasonally polyestrous mare has a variety of unique characteristics in ovarian structure and general reproductive function. Among the anomalies of ovarian development is the bovine freemartin with gonads containing a mixt...

Cycling ewes with lesions placed in the anterior region of medial basal hypothalamus (MBH) showed no estrous behavior, but they all had ovulations and cyclical corpora lutea at physiological terms. Participation of the anterior region of MBH in control of sexual behavior was also supported by the experiments on castrated sheep implanted with 17-beta-estradiol into the area determined previously...

The pioneer work of Klein on unilaterally pregnant rabbits, rats and hamsters (Klein, 1933, 1935, 1938) established the role of the pregnant uterus in maintaining, independently of the foetuses, the histological structure and function of the corpora lutea of pregnancy. If the pregnant horn were removed from unilaterally pregnant animals in mid-pregnancy, degeneration of the corpora lutea follow...

The objective of this study was to compare three superovulation protocols in dromedary camels. Follicular waves of dromedary camel donors (n=6) were synchronized using two GnRH injections. Superovulation was initiated 2 days after the second injection (day 0 of experiment). The experiment was conducted using change over design, where all females received three superovulation treatments one afte...