Banca de DEFESA: BRENO BARROS DE SANTANA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : BRENO BARROS DE SANTANA
DATE: 31/05/2023
TIME: 09:00
LOCAL: AUDITÓRIO
TITLE:

EFFECT OF TIME AND TEMPERATURE VARIABLES ON EQUINE OOCYTE MAINTENANCE AND RESVERATROL ON ASININE OOCYTE VITRIFICATION

KEY WORDS:

Oocytes, donkeys, vitrification

PAGES: 94
BIG AREA: Ciências Agrárias
AREA: Medicina Veterinária
SUBÁREA: Reprodução Animal
SPECIALTY: Ginecologia e Andrologia Animal
SUMMARY:

The objective of the present study was to evaluate the viability of equine oocytes during a24-hour period at
three different temperatures. And to evaluate gene expression and ultrastructure of vitrified equus asinus
oocytes in two storage devices in medium supplemented with resveratrol (resv). Ten mares were selected for
transvaginal aspirationof oocytes. After collection, the oocytes were selected and divided into 4 groups: G0-
post-aspiration stained; G1-kept for 24 hours at 37°C; G2-kept for 24 hours at 22.5°C; G3-kept for 24 hours
at 5°C. After this period, the oocytes were stained with 4 mM-calcein-AM and 2mM ethidium-1 homodimer to
assess viability. After staining, oocytes were fixed, washed, and kept refrigerated at 5°C until evaluation. For
donkey oocytes, cumulus oocyte complexes obtained from ovaries from slaughterhouse donkeyswere used.
The 200 oocytes collected were selected and divided into 4 groups where they were washed in base medium
(MB): MB composed of TCM-199 + 0.014% BSA. And vitrified in the following Devices: VIT A-vitrification
vitrification straws (WTA®) and VIT B-0.25ml straws, where 5 oocytes were vitrified per device as follows :
VIT A 1 and VIT B 1-Control: MB + 10% (v/v) ethylene glycol-EG + 10% (v/v) dimethylsulfoxide-DMSO;
VIT A 2 and VIT B 2 Control MB + 20% (v/v) EG, 20% (v/v) DMSO + 0.5 M sucrose; VIT A1 and VIT B 1
Resv: MB + 10% (v/v) EG + 10% (v/v) DMSO + 20 uM of Resv; VIT A 2 and VIT B 2 Resv: MB + 20% (v/v)
EG, 20% (v/v) DMSO + 0. 5 M sucrose + 20 uM Resv. After vitrification the oocytes were kept frozen in liquid
nitrogen until evaluation. Equine oocytes were evaluated under an epifluorescence microscope, considering
viable cytoplasm marked in green and chromatin not marked with ethidium-1 homodimer (red). Sixty-two
oocytes were obtained from 126 aspirated follicles (49.2% recovery rate).No statistical difference was observed between groups; In order to evaluate the asinine oocytes, they were devitrified (37°C), the gene analysis was performed using the quantitative real-time PCR method (qRT-PCR) for the Bax, Mater and Bmp15 genes, we canobserve that there is no difference between gene expression in the studied groups. As for the ultrastructure of the oocytes after devitrification, at least 3 were selected and evaluated in a transmission electron microscope (TEM) for the integrity of their structures, where it was observed that the addition of resveratrol to the medium was harmful to the ultrastructure when compared to the other groups. In conclusion, the results observed in maintaining the temperature of equine oocytes show us that equineoocytes can be maintained for 24 hours at temperatures of 22, 5 and 37°C without changes in their viability. As for the donkey oocytes, it was observed that the addition of resveratrol at a concentration of 20 uM does not alter gene expression, but presents lesions in the structure of the oocytes. As this is the first study of the addition of resveratrol in the vitrification medium of oocytes of the asinine species, further studies are needed so that it can evaluate, for example, other concentrations of resveratrol as well as the development of these oocytes after devitrification in the process of maturation, fertilization and embryonic development.

COMMITTEE MEMBERS:
Externo ao Programa - 3085776 - ANDRE MARIANO BATISTA - nullExterno ao Programa - 1511486 - CLAUDIO COUTINHO BARTOLOMEU - nullExterna à Instituição - FERNANDA PEREIRA DA SILVA BARBOSA
Interno - GUSTAVO FERRER CARNEIRO
Externa à Instituição - LÚCIA CRISTINA PEREIRA ARRUDA - UFRPE
Externo à Instituição - RAFAEL ARTUR DA SILVA JÚNIOR
Externo ao Programa - 1234222 - VICTOR NETTO MAIA - null