JBRA Assisted Reproduction 2025;29(Suppl.2 SBRA 2025):193
Poster Presentation
29^th Annual Congress of the SBRA. São Paulo/SP - Brazil, 2025
doi: 10.5935/1518-0557.20263892

P-181. Production of Bovine Embryos Using a Single Medium for All Stages of IVP

Amanda Talys Sampaio¹, Bruno Henrique Couto Oliveira¹, Rafael Martins Tonzar¹, Natalia Vitor dos Santos¹, Maria Eduarda Campos Ferreira¹, Caroline Schiavão Fernandes¹, Bruno Carrino Suave¹, Anthony Cesar de Souza Castilho¹, Caliê Castilho¹

¹ Universidade do Oeste Paulista (UNOESTE) - Presidente Prudente - SP - Brasil

Objective: In vitro embryo production (IVP) has become an important tool in bovine breeding, contributing to advances in genetic improvement and reproductive efficiency. IVP involves three main phases: in vitro maturation (IVM), in vitro fertilization (IVF), and in vitro culture (IVC), traditionally requiring a different culture medium for each phase to meet the specific needs of gametes, zygotes, and embryos. A further development of this biotechnology is the development of a single, suitable medium that can support all stages of IVP.
Methods: In this study, bovine ovaries were collected from an abattoir and immediately transported to the laboratory in physiological saline at 35°C. Antral follicles (3–8 mm in diameter) were aspirated with a 40 × 12 mm needle attached to a 10-mL syringe. The collected cumulus-oocyte complexes (COCs) were randomly divided into two groups: a control group that matured in TCM-199 supplemented with 75 µg/mL amikacin, 4 mg/mL bovine serum albumin (BSA), 0.01 IU/mL recombinant FSH, 0.001 µg/mL 17β-estradiol, 1 µM cysteamine, and 10% fetal bovine serum (FBS); and the SOF group, which matured in synthetic oviduct fluid (SOF) consisting of NaCl (107.63 mM), KCl (7.16 mM), KH₂PO₄ (1.19 mM), MgSO₄ (1.51 mM), CaCl₂2H₂O (1.78 mM), sodium lactate (5.35 mM), NaHCO₃ (25.00 mM), sodium pyruvate (7.27 mM), L-glutamine (0.20 mM), BME amino acids (45.0 µL/mL), MEM essential amino acids (5.0 µL/mL), trisodium citrate (0.34 mM), myo-inositol (2.77 mM), gentamicin (50 µg/mL), amikacin (78.125 µg/mL), 4% BSA, and 10% FBS, without hormones, for 22–24 hours of maturation. After maturation, the oocytes were subjected to IVF using thawed bull semen. The control group was fertilized in standard IVF medium (TL Stock) supplemented with BSA (6 mg/mL), pyruvate (2 µL/mL of a 100 mM solution), gentamicin (75 µg/mL), heparin (µg/mL), and PHE solution (penicillamine, hypotaurine, epinephrine, 44 µL/mL). In the SOF group, TL stock was replaced with SOF medium for 18-20 hours, while all other supplements were maintained, –. After fertilization, the cumulus cells were removed and both groups were cultured for 7 days in SOF standard medium supplemented with 2.5% FBS and 13 mM pyruvate. Cleavage was assessed at day 3 (D3) and embryo development and quality at day 7 (D7).
Results: The cleavage rate (70.4% vs. 44.1%) was significantly higher (p=0.0008) in the control group than in the SOF group. The blastocyst rate (19.1% vs. 6.7%) was also significantly higher in the control group (p=0.0030).
Conclusion: It can be concluded that the control group had a higher cleavage and blastocyst formation rate under the conditions evaluated. Although the SOF group showed lower performance, modifications in the formulation may be necessary to increase its efficacy in supporting bovine in vitro embryo development.