Follicle-stimulating hormone from different species has been used to increase ovulation and calving rates in cattle, injections proving to be most successful when given during the late follicular phase of the oestrous cycle or in combination with progestagens (Willett & Buckner, 1953; Bellows, Anderson & Short 1969). Some investigations have resulted in substantial increases in ovulation and ca...

Follicle-stimulating hormone regulation of estrogen biosynthesis in the adult rodent ovary requires β-catenin (CTNNB1), but whether CTNNB1 is involved in FSH-induced estrogen production in cattle is unknown. To elucidate the effect of FSH in regulating specific wingless-type mouse mammary tumor virus integration site (WNT)/CTNNB1 pathway components in bovine folliculogenesis and steroidogenesis...

Paracrine cell signaling is believed to be important for ovarian follicle development, and a role for some members of the fibroblast growth factor (FGF) family has been suggested. In the present study, we tested the hypothesis that FGF-8 and its cognate receptors (FGFR3c and FGFR4) are expressed in bovine antral follicles. RT-PCR was used to analyze bovine Fgf8, Fgfr3c and Fgfr4 mRNA levels in ...

Luteinizing hormone as other glycoprotein hormones is characterized by a heterodimeric structure composed a common α-subunit noncovalently linked to a specific β-subunit. The correct conformation of the heterodimer is important for efficient secretion, hormonal-specific post-translational modifications, receptor binding and signal transduction. To determine whether αand βsubunits can be synthes...

Developmental competence of in vitro matured (IVM) oocytes needs to be improved and this can potentially be achieved by adding recombinant bone morphogenetic protein 15 (BMP15) or growth differentiation factor (GDF9) to IVM. The aim of this study was to determine the effect of a purified pro-mature complex form of recombinant human BMP15 versus the commercially available bioactive forms of BMP1...

Background: Bovine follicle-stimulating hormone (bFSH) is a heterodimer hormone that consists of a common -subunit which noncovalently associated with the hormone-specific -subunit. During the past 15 years, the methylotrophic yeast Pichia pastoris has become an important host organism for recombinant protein production because it is able to use methanol as a sole carbon and energy source. Th...

AIM The aim of this study was to investigate the effect of kisspeptin (KP) on in vitro maturation (IVM) of sheep oocytes aspirated from the ovaries collected from slaughterhouse. MATERIALS AND METHODS Two different experiments were conducted to investigate the effect of KP (5, 10 and 15 µg/ml) alone (experiment 1) or in combination with follicle-stimulating hormone (FSH), luteinizing hormone ...

The objectives of two studies were to determine 1) whether plasma concentrations of inhibin (INH) changed with age in prepubertal bulls and whether these changes were related to changes in FSH, testosterone or testis length; and 2) whether castration and(or) estradiol implants affected plasma concentrations of INH and FSH. In Exp. 1, plasma INH remained constant from 4 until 8 wk of age then in...

Understanding the mechanisms regulating oocyte developmental competence is essential to enhance the clinical efficiency of assisted reproduction. FSH orchestrates the acquisition of oocyte competence, both in vivo and in vitro. Multiple pathways are implicated in FSH signalling; however, their precise coordination remains unresolved. A robust system to investigate FSH signalling is oocyte in vi...