Effect of different transport temperatures on in vitro maturation of oocytes collected from frozen-thawed sheep ovaries

1Citations
Citations of this article
8Readers
Mendeley users who have this article in their library.

Abstract

The aim of this study was to determine the effects of 2 different transport temperatures on the in vitro maturation of oocytes collected from frozen-thawed sheep ovaries. Sheep ovaries were transferred into saline at temperatures of 4 °C and 32 °C. After the 2 experimental groups (A: fresh cortex, B: frozen-thawed cortex) were formed, each group was divided into 2 subgroups (group A1: 4 °C, group A2: 32 °C [control]; group B1: 4 °C, group B2: 32 °C). The cortexes were dissected into slices 1-3 mm thick and pieces of 0.5 cm2. For groups B1 and B2, 1-2 cortex pieces were placed in cryogenic vials containing 1 mL of freezing medium modified with Earle's salts (TCM-199) and supplemented with 10% fetal calf serum (FCS) (FCS + 2.5 M ethylene glycol + 0.1 M sucrose). The vials were then cooled to -7 °C at 2 °C/min and held at -7 °C for 10 min for manual seeding. The temperature was then lowered by -0.3 °C/min to -35 °C and thereafter by -10 °C/min to -75 °C. Vials were plunged into -196 °C liquid nitrogen and stored. Cortexes were thawed at 37 °C. Collected oocytes were matured in their own groups in 700 μL of TCM-199 (supplemented with luteinizing hormone, follicle-stimulating hormone, pyruvate, and FCS) for 23 h in a gas mixture of 5% CO2, 5% O2, and 90% N2 at 38.8 °C. After maturation, oocytes were fixed in acetic acid and ethyl alcohol (1:3) for 48 h. Oocytes were stained with aceto-orcein and then examined. At the end of the study, maturation rates for reaching metaphase I (MI) were similar in all groups (group A1: 30.76%, group A2: 38.09%, group B1: 30.65%, and group B2: 33.33%). The rates at which metaphase II (MII) was reached were 18.58%, 34.69%, 7.25%, and 6.48%, respectively. The best development was seen in group A2 (P < 0.001). Sheep oocytes obtained from fresh and frozen-thawed cortexes reached the MII stage if transported at 4 °C. © TÜBİTAK.

Cite

CITATION STYLE

APA

Özdaş, Ö. B., Baran, A., Taş, M., Cirit, Ü., Demir, K., Bacinoǧlu, S., … Ak, K. (2013). Effect of different transport temperatures on in vitro maturation of oocytes collected from frozen-thawed sheep ovaries. Turkish Journal of Veterinary and Animal Sciences, 37(1), 15–19. https://doi.org/10.3906/vet-1104-24

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free