rbST Effects on in Vitro Embryo Production in Andean Cattle

Unchupaico-Payano I.; Arauco-Villar F.; Ninahuanca-Carhuas J.; Quispe-Eulogio C.; Ancco-Gomez E. · Acta Fytotechnica et Zootechnica (2025) · DOI: 10.15414/afz.2025.28.04.317-323

Resumen

The efficiency of invitro fertilization (IVF) in cattle depends on various factors, including the quality and quantity of oocytes collected. Recombinant bovine somatotropin (rbST) has been suggested to improve ovarian follicular development and oocyte recovery by enhancing insulin-like growth factor-1 (IGF-1) receptor activity. However, its effects on metabolic parameters and in vitro embryo production remain unclear, especially in high-altitude systems like the Andean region of Peru. This study aimed to determine the effects of rbST administration, in two different doses, within a hormonal protocol for follicular wave synchronization and in vitro embryo production in Brown Swiss cows in Andean region. Twenty-four cows were randomly assigned to three groups: T1 (500 mg rbST), T2 (250 mg rbST), and T3 (control, no rbST). Oocyte collection sessions were performed every 14 days, and variables such as follicle size, oocyte recovery, oocyte viability, β-hydroxybutyrate (BHB), glucose, total proteins, urea, oocyte maturation, and blastocyst rates were evaluated. Results showed that 500 mg rbST significantly increased (P ≤0.05) the number of 2–4 mm follicles, as well as total and viable oocyte recovery. rbST also reduced BHB levels and increased circulating glucose (P ≤0.05). However, no significant differences were observed in oocyte maturation or blastocyst rates across the treatments. In conclusion, 500 mg of rbST enhances the recovery of viable oocytes but does not significantly affect final embryo production in vitro. Further studies are needed to explore the long-term effects of rbST on reproductive performance in high-altitude cattle systems. © Licensed under a Creative Commons Attribution 4.0 International License

Instituciones: Universidad Peruana Los Andes; Universidad Nacional del Centro del Perú