BACKGROUND Rats made hypothyroid with propilthyouracil start showing abnormal cycling on the second cycle after the start of the treatment, with a high proportion of spontaneous pseudopregnancies and reduced fertility. METHODS To investigate some of the mechanisms involved in these reproductive abnormalities, hypothyroidism was induced in virgin rats by propilthyouracil (0.1 g/L in the drinki...

Progesterone is a potent drug for synchronization of the estrus and ovulation cycles in bovine. At present, the estrus cycle of bovine is controlled by the insertion of progesterone-embedded silicone bands. The disadvantage of nondegradable polymer inserts is to require for disposal of these bands after their use. The study currently focuses on preparation of biodegradable progesterone-incorpor...

The frequency of breast cancer metastatic spread is affected by the menstrual cycle phase of its resection. Breast cancer growth, post-resection spread, and cure frequency are each modulated by the estrous cycle in C(3)HeB/FeJ mice. Tumor metastases are 2- to 3-fold more frequent when the resection is done during diestrus as compared with estrus. Tumor angiogenesis is essential for both cancer ...

The objectives of this study were to evaluate the effects of flunixin meglumine (FM), an inhibitor of PGF2α synthesis, administered at the time of embryo transfer (ET) and insertion of an intravaginal progesteronereleasing device (CIDR) at the time of ET on pregnancy rates (PR) and the resynchronization of estrus. Beef cows (n = 552) and heifers (n = 160) in three locations were assigned random...

melanocortin- 4 receptor (mc4r) and agouti- related peptide (agrp) are involved in energy homeostasis in rats. according to mc4r and agrp effects on luteinizing hormone (lh) secretion, they may influence the estrous cycle of rats. therefore, the aim of this study was to investigate the expression of mc4r and agrp mrnas at different stages of estrous cycle in the rat’s hypothalamus. the estrous ...

The aims of this study were to determine whether a single treatment of estradiol dipropionate (EDP) could induce pseudopregnancy in gilts and to determine the effectiveness of PGF(2alpha) treatment on estrus synchronization in EDP-induced pseudopregnant gilts. In experiment 1, gilts were treated with 20 mg of EDP (n=11) or vehicle (n=5) on Day 12 (Day 0=onset of estrus). Establishment of pseudo...

AIM Timely estrus detection is one of the critical factors for increasing reproductive efficiency in buffaloes. In recent decades, saliva has become a more popular as a noninvasive source for determining physiological status of animals by various biochemical electrolytes. This study was designed to assess and correlate changes in different salivary minerals concentration (calcium, inorganic pho...

Kisspeptin and RFamide-related peptide-3 (RFRP-3) are known to affect GnRH/luteinizing hormone (LH) in several species, including the rat. It has been hypothesized that GnRH/LH changes during the rat estrous cycle may result from changes in the expression of KiSS1 and RFRP-3 genes. Therefore, the present study investigates KiSS1 and RFRP-3 gene expression at the transcriptional level in the rat...

One hundred and .tWO puberal gilts from nine genetic groups were used to determine the association of two morphological types of Ovarian follicular loss (hemorrhagic and milky) with genetic background of ~gilts, level of feed intake and stage of estrous cycle. At estrus (day 0 of estrous cycle) a lesser prqportion of gilts (P<.05) had hemorrhagic foiiicles than gilts at day-15. While the total ...

I T is generally considered that uterine motility is high during the follicular phase of the estrous cycle and relatively low during the luteal phase, although motility during the luteal phase varies somewhat among studies. In sheep, neither the variation in spontaneous uterine motility during the estrous cycle nor the effects of exogenous ovarian hormones on this motility have been studied ext...