Using Cumulus Cell Biopsy as a Non-Invasive Tool to Access the Quality of Bovine Oocytes: How Informative Are They?

The present study aimed to determine whether cumulus cells (CC) biopsy, acquired before or after in vitro maturation (IVM), presents similar gene expression pattern and if would compromises oocyte quality. First, immature cumulus oocyte complexes (COCs) were distributed: (1) maturated in groups (control); (2) individually maturated, but not biopsied; (3) subjected to CC biopsy before maturation and individually matured; (4) individually matured and submitted to CC biopsy after maturation; (5) individually matured and CC biopsied before and after maturation. Secondly, candidate genes, described as potential markers of COCs quality, were quantified by RT-qPCR in CCs before and after IVM.

The use of insulin-transferrin-selenium (ITS), and folic acid on individual in vitro embryo culture systems in cattle.

Individual embryo culture is the only strategy that allows the tracking of embryos throughout the culture period. However, this procedure leads to lower embryo development. This study aimed to evaluate different alternatives to improve embryo development in a single in vitro production system.

Transcriptome of D14 in vivo x in vitro bovine embryos: is there any difference?

It is well-established that in vitro culture affects quality, gene expression, and epigenetic processes in bovine embryos and that trophectoderm cells are the most susceptible to abnormalities. These changes have been reported as the main factors responsible for losses observed after transfer of in vitro-produced embryos. The present study aimed to investigate the effect of an in vitro system on bovine embryo transcriptional profiles on D14 of development.

The Replacement of Fetal Bovine Serum with Bovine Serum Albumin During Oocyte Maturation and Embryo Culture Does Not Improve Blastocyst Quality After Slow Freezing Cryopreservation.

In the present study, four experimental groups were used: fresh embryos, cultured during maturation and culture in media supplemented with bovine serum albumin (BSA) (fresh BSA) or fetal bovine serum (FBS) (fresh FBS); and two groups of cryopreserved and thawed embryos, produced under the same conditions (frozen BSA and frozen FBS). Experiment 1 evaluated the protein source effect on embryo development and response to cryopreservation. At day 7, half of the expanded blastocysts (Bx) from each group were cryopreserved and warmed and the other half were used as controls.

Bovine epididymal spermatozoa treatment for in vitro fertilization: Heparin accelerates fertilization and enables a reduction in coincubation time.

This study aimed to establish a protocol for in vitro embryo production using epididymal sperm (EP). Samples were obtained from ejaculated sperm (EJ) and the epididymis of 7 Gir bulls. First, the effect of heparin (+) on the viability, longevity (Experiment 1) and fertilization rates (Experiment 2) of the EP was evaluated.

Effect of prematuration and maturation with fibroblast growth factor 10 (FGF10) on in vitro development of bovine oocytes.

In an attempt to improve in vitro embryo production, we investigated the effect of FGF10 and 0.1 mM of cilostamide, cAMP modulator, during in vitro prematuration (PIVM) and in vitro maturation (IVM) on the developmental capacity of bovine oocytes. Five treatments (T) were used as follows: T1) IVM (control): COCs were matured for 22 h; T2) PIVM/IVM: COCs were submitted to 22 h of PIVM and 22 h of IVM; T3) PIVM + FGF10/IVM: COCs were submitted to PIVM for 22 h in the presence of FGF10 and matured for 22 h; T4) PIVM/IVM + FGF10: COCs were submitted to PIVM for 22 h and matured for 22 h in the presence of FGF10; and T5) PIVM + FGF10/IVM + FGF10: COCs were submitted to 22 h of PIVM and 22 h of IVM, both in the presence of FGF10.

Bovine in vitro embryo production: the effects of fibroblast growth factor 10 (FGF10).

Purpose: In an attempt to improve in vitro embryo production, we investigated the effect of fibroblast growth factor 10 (FGF10) during in vitro maturation on the developmental capacity of bovine oocytes.

Material And Methods: Cumulus-oocyte complexes (COCs) were aspirated from follicles of 3-8 mm diameter. After selection, the COCs were matured in medium with or without 0.

Characterization of the IGF2 Imprinted Gene Methylation Status in Bovine Oocytes during Folliculogenesis.

DNA methylation reprogramming occurs during mammalian gametogenesis and embryogenesis. Sex-specific DNA methylation patterns at specific CpG islands controlling imprinted genes are acquired during this window of development. Characterization of the DNA methylation dynamics of imprinted genes acquired by oocytes during folliculogenesis is essential for understanding the physiological and genetic aspects of female gametogenesis and to determine the parameters for oocyte competence.