163 Superovulation efficiency by using different FSH-derived protocols in cattle: bovine medium-acting recombinant FSH versus conventional FSH
M. Gutiérrez-Reinoso A B , C. Aguilera A , F. Navarrete A , J. Cabezas A , F. Castro A , I. Cabezas A , O. Sánchez C , L. Rodríguez-Alvarez A and M. Garcia-Herreros DA Universidad de Concepción (UdeC), Chillán, Chile
B Universidad Técnica de Cotopaxi (UTC), Latacunga, Ecuador
C Centro de Biotecnología y Biomedicina Spa (CBB), Concepción, Chile
D Instituto Nacional de Investigação Agrária e Veterinária (INIAV), Santarém, Portugal
Reproduction, Fertility and Development 34(2) 319-320 https://doi.org/10.1071/RDv34n2Ab163
Published: 7 December 2021
© 2022 The Author(s) (or their employer(s)). Published by CSIRO Publishing on behalf of the IETS
In vivo production of bovine embryos by using conventional pituitary-derived FSH in superovulation (SOV) protocols has been characterised by the relatively low embryo quality and yield obtained. The aim of the present study was to determine whether administration of a single dose of bovine medium-acting recombinant FSH (bscFSH-r) developed in our laboratory could generate an efficient SOV response compared withh a conventional FSH (NIH-FSH-p) pituitary-derived protocol in cattle. A single-chain recombinant bovine FSH (bscFSH-r) gene sequence variant was designed considering the Bostaurus α and β chains linked through a flexible spacer peptide with 6 N-glycosylation sites. Sixty-eight healthy Red Angus cows (body weight: 450 ± 50 kg; body condition score: 3.5 ± 0.5) were randomly distributed into two experimental groups (G): G1 (NIH-FSH-p: FSH from purified pig pituitary extract; n = 34) and G2 (bscFSH-r: recombinant FSH; n = 34). Regarding G1 SOV, a conventional protocol was applied (Day 0: intravaginal progesterone (P4) device (CIDR: 1.38 g) + 2.5 mg intramuscular (IM) oestradiol benzoate E2B + 100 mg P4 (IM); Day 4: total dose = 280 mg of NIH-FSH-p divided in 4 day/12 h intervals/8 decreasing doses: 50/50 + 40/40 + 30/30 + 20/20 mg; Day 6: fifth and sixth NIH-FSH-p dose + two PGF2α i.m. doses (500 µg of D-cloprostenol each); Day 7: CIDR removal at the seventh NIH-FSH-p dose application). For G2 cows, the same protocol was applied with modifications (total dose = 170 µg of bscFSH-r divided in 4 day/24 h intervals/4 decreasing doses: 60 + 50 + 40 + 20 µg). Blood samples were collected during the SOV protocols: Day 0 (CIDR application), Day 4 (first FSH application), Day 8 (oestrus), and Day 15 (embryo collection) for P4 and cortisol assessment by using radioimmunoassay. Ovarian structures (ovary size, F and CL) were monitored by using ultrasonography at the same timeline points. Morphological embryo classification and quality were performed according to the IETS guidelines. The data were analysed by GLMM (SPSS® 25, IBM Corp.). No significant differences were detected regarding P4 or cortisol concentrations between G1 and G2 at each time point (P > 0.05). Significant differences were observed between G1 and G2 for ovary size until Day 8 (P ≤ 0.05) but not at Day 15 (P ≥ 0.05). CL number was statistically higher in G2 (P ≤ 0.05). Significant differences were observed between G1 and G2 for total structures collected (8.0 ± 0.6 vs. 10.3 ± 0.8) as well as for the number of viable embryos (6.3 ± 0.5 vs. 8.6 ± 0.6), morulae (2.8 ± 0.5 vs. 5.4 ± 0.7), and degenerated embryos (1.3 ± 0.2 vs. 0.4 ± 0.1; P ≤ 0.05). In conclusion, including bscFSH-r in SOV protocols would be a viable alternative by reducing the number of applications and offering a greater SOV response together with efficient production of viable embryos compared with the conventional pituitary-derived FSH SOV protocols.
This research was partially supported by Fondef ID18I10082-ANID 21201280.
