Relatório de Estágio Supervisionado Obrigatório (ESO) realizado na Empresa Brasileira de Pesquisa Agropecuária - EMBRAPA Gado de Leite, Juiz de Fora e no Laboratório de Biotécnicas Aplicadas à Reprodução do Departamento de Medicina Veterinária da Universidade Federal Rural de Pernambuco: efeito da adição de nanoemulsão à base de óleo essencial rico em limoneno ao diluente de refrigeração de sêmen caprino

Abstract

The present study aims to report the activities carried out in compliance with the discipline 08525 - Mandatory Supervised Internship (MSI), part of the Bachelor's Degree in Veterinary Medicine, conducted between October 2, 2023, and November 28, 2023, at the Brazilian Agricultural Research Corporation (Embrapa), in the Dairy Cattle unit in the municipality of Juiz de Fora - MG, and between January 2 and January 19, 2024, at the Laboratory of Biotechniques Applied to Reproduction (LBR) of the Department of Veterinary Medicine (DMV) of the Federal Rural University of Pernambuco (UFRPE). The activities carried out provided in-depth training in in vitro embryo production (IVP) techniques for research purposes, including follicular aspiration of ovaries from abattoirs, in vitro maturation (IVM), in vitro fertilization (IVF), and in vitro embryo culture (IVC). Activities in the field of molecular biology involving DNA extraction and amplification through the Polymerase Chain Reaction (PCR) technique were also performed. In the second chapter of this study, a research was conducted to evaluate the effect of adding nanoemulsion based on limonene-rich essential oil extracted from wild orange peel (NELS) to the semen extender of goat breeders. Seminal samples from five Saanen breed goats were used for the research. Each seminal pool was diluted in Tris-egg yolk supplemented with NELS at concentrations of 1.25, 2.5, and 5% at a concentration of 200 × 106 sperm/mL. The samples were placed in Eppendorf tubes (1.5 mL) and stored in refrigeration boxes (botuflex®) for cooling curve determination up to 5 ºC, and after 2 hours, they were transferred to the refrigerator, also at a controlled temperature of 5 ºC. For each analysis, part of each sample was aliquoted and transferred to other Eppendorf tubes (1.5 mL) in a dry bath at 37 ºC and subsequently evaluated in the Computer-Assisted Sperm Analysis System (CASA) for sperm kinetics, and in epifluorescence microscopy for Mitochondrial Membrane Potential (MMP), Plasma Membrane Integrity (PMI), and Acrosomal Membrane Integrity (AMI). The addition of wild orange nanoemulsion to the Tris-egg yolk extender was not able to improve sperm motility and kinetic parameters, besides significantly reducing MMP after 24 hours of refrigeration.