Banca de DEFESA: JEFFERSON AYRTON LEITE DE OLIVEIRA CRUZ

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : JEFFERSON AYRTON LEITE DE OLIVEIRA CRUZ
DATE: 25/04/2023
TIME: 15:00
LOCAL: Auditório da Área de Reprodução Animal do Departamento de Medicina Veterinária
TITLE:

Ultrastructural evaluation of bovine embryos produced in vitro vitrified by the cryotop method

KEY WORDS:

Electron microscopy; embryonic cells; cryopreservation.

PAGES: 50
BIG AREA: Ciências Agrárias
AREA: Medicina Veterinária
SUBÁREA: Reprodução Animal
SPECIALTY: Fisiopatologia da Reprodução Animal
SUMMARY:

Agribusiness in Brazil has grown at high rates, supplying the national market and decisively cooperating with exports, especially beef products, positively influencing the Gross Domestic Product (GDP) year after year. With Brazil occupying a prominent position in this sector, it reflects an increase in research requirements and investments to improve quality and, consequently, in numbers, which generate economic development. One of the ways to make this growth viable is in genetic selection, with the improvement of favorable characteristics, through reproductive biotechnologies, such as in vitro production (IVP) and cryopreservation techniques. With the use of these biotechniques it is possible to store the genetic material of a donor for better use of surplus embryos. This study aimed to align the use of Transmission Electron Microscopy (TEM) in the ultrastructural evaluation of bovine embryos produced in fresh in vitro (GF) and after vitrification process in cryotop (GV). 15 embryos per group were fixed. Each embryo was fixed separately, making ultrathin cuts and placed in an ideal medium for MET evaluation. This method gave relevance to the morphological analysis of mitochondria and their cristae, as well as demonstrating changes in the endoplasmic reticulum, golgi complex, microvilli in the trophectoderm and integrity of the zona pellucida after chemical treatments used during the vitrification process with cryotop. It was concluded that the cryotop vitrification process can cause ultrastructural alterations such as intracellular disorganization, dilation of organelles such as mitochondrial cristae, RER, REL and a decrease in the presence of ribosomes in the RER, since the morphological data visualized here in this experiment suggested that the maintenance of functional embryo viability after cryotop vitrification was maintained, making vitrification a method that, despite the stress on its organelles, maintained embryonic viability.

COMMITTEE MEMBERS:
Presidente - ANDRE MARIANO BATISTA
Interno - CLAUDIO COUTINHO BARTOLOMEU
Externo à Instituição - RAFAEL ARTUR DA SILVA JÚNIOR