Effect of follicular fluid supplementation during in vitro maturation on total cell number in bovine blastocysts produced in vitro

Abstract

-This study evaluated the influence of follicular fluid (FF) added to the maturation medium on the quality of bovine embryos produced in vitro. In the first experiment, oocytes were matured in media containing five different FF concentrations with different maturation times and classified according to meiotic progression and migration of cortical granules. In the second experiment, oocytes matured in the same media were fertilized at three different maturation times; thereafter, cleavage and blastocyst rates were evaluated. In the third experiment, oocytes were matured in media containing three different FF concentrations at two different maturation times, and embryo quality, inferred by the ratio of inner cell mass and trophectoderm cells compared with total cell number, was evaluated. Higher FF concentration (75 -100% FF) slowed meiotic progression and CG migration (control -78.13% vs. treated -52.58% and control -52.7% vs. treated -11.59%, respectively, at 24 h of maturation). Also, FF at concentration of 75% or 100% had a negative influence on cleavage and blastocyst rates (control -90.13% vs. treated -82.64% and control -35.73% vs. treated -11.57%, respectively, at 24 h of maturation). The 50% FF resulted in embryos with increased inner cell mass numbers (control -29.91 vs. treated -35.49, at 24 h of maturation) and total cell numbers (control -109.53 vs. treated -120.67, at 26 h of maturation). Even though higher concentration of FF added to the maturation medium reduced embryonic development rates, in lower concentrations, FF slowed the meiotic progression and migration of CG and contributed to increases in inner cell mass number. Thus, FF added to the maturation medium enhances the number of cells in bovine embryos produced in vitro, especially for inner cell mass.

Changes of follicular fluid composition during estrous cycle: The effects on oocyte maturation and embryo development in vitro

“…In a recent study, Algriany et al (2004) investigated nuclear maturation of porcine cumulus oocyte complexes (COCs) cultured in pFF, which collected from three different batches of slaughterhouse ovaries and they did not find any significant differences between batches. Similar result was obtained by Coelho Cruz et al (2014) using bovine follicular fluid. Collectively, these studies given experimental background to the hypothesis that follicular fluid collected from large and highly vascularized follicles of slaughterhouse ovaries support developmental competence as FF collected from in vivo.…”

“…It could be concluded that FF supplementation to maturation medium at 10% (Oberlender et al, 2013); 20% (Mohammed et al, 2005) and 30-50% (Coelho Cruz et al, 2014) improved development of oocytes. However, 60% or more of FF has a detrimental effect on embryon development (Choi et al, 1998;Coelho Cruz et al, 2014).…”

“…It could be concluded that FF supplementation to maturation medium at 10% (Oberlender et al, 2013); 20% (Mohammed et al, 2005) and 30-50% (Coelho Cruz et al, 2014) improved development of oocytes. However, 60% or more of FF has a detrimental effect on embryon development (Choi et al, 1998;Coelho Cruz et al, 2014). We could conclude also that concentrations of FF collected from large and healthy follicle in diluted level (10-50%) during IVM may favorably influence oocyte maturation and embryo development in bovine, ovine and pig, whereas high concentrations of FF in mares is tolerable during IVM and gave positive results.…”

“…bFF collected at 0 or 4 hr following LH surge appeared to possess a meiosis-inhibiting activity that is absent from follicular fluid collected at 8 hrs or more after LH surge (Romero-Arredondo and Seidel, 1994). Coelho Cruz et al (2014) investigated maturation and embryo development upon adding bovine follicular fluid to maturation medium (25, 50, 75, 100%) which collected from follicle with diameter 8-15 mm. They found that high FF concentration (75 -100% FF) slowed meiotic progression and cortical granule migration.…”

Insulin-Like Growth Factor-I Concentration in the Follicular Fluid of Bali Cattle and Its Role in the Oocyte Nuclear Maturation and Fertilization Rate

“…Agung et al (2013) reported that the use of porcine follicular fluid as a sole maturation media resulted in the formation of male pronuclear after in vitro fertilization in the matured porcine oocytes. Furthermore, Cruz et al (2014) reported that the addition of follicular fluid at lower concentration in maturation media enhanced the total cell numbers in bovine embryos produced in vitro.…”