Muñoz García, Carmen C.Luis Calero, MarcosFernández Hernández, PabloPizarro Hernández, AlbaFernández González, RaúlGutiérrez Adán, AlfonsoSánchez Calabuig, María JesúsCuervo Arango, JuanGonzález Fernández, LauroMacías García, Beatriz2024-10-302024-10-302024Muñoz-García, C. C., Luis-Calero, M., Fernández-Hernández, P., Pizarro-Hernández, A., Fernández-González, R., Gutiérrez-Adán, A., Sánchez-Calabuig, M. J., Cuervo-Arango, J., González-Fernández, L., & Macías-García, B. (2024). A new hormonal protocol supports early development of in vitro-produced embryos after transfer to anoestrus mares. Reproduction in Domestic Animals, 59(Suppl. 3), e14622. https://doi.org/10.1111/rda.146220936-676810.1111/rda.14622https://hdl.handle.net/20.500.14352/109800Marcos Luis-Calero ha contado con el apoyo del ‘Plan Propio de Iniciación a la Investigación, Desarrollo Tecnológico e Innovación. Acción II’ de la Universidad de Extremadura y del Banco Santander; Referencia: RC1. Carmen C. Muñoz-García se financia por el ‘Programa Investigo’ de la Junta de Extremadura; Reference: PI-0152-22.The present study aimed to evaluate whether primed anoestrus mares are suitable recipients for embryos produced by intracytoplasmic sperm injection (ICSI). Anoestrus was confirmed in four mares and daily doses of oestradiol benzoate (6 mg in total) over 5 days were administered; after 3 days of rest, oral altrenogest was administered at 0.088 mg/kg and embryos (1 to 5 embryos per mare; 15 in total) were transferred 3.5 days after progesterone onset. Uterine lavage was conducted 48 h after transfer. The results revealed an 80% embryo recovery rate, and among the retrieved embryos, 67% showed evident intrauterine development. Hence, ICSI-derived embryos can be successfully transferred to primed anoestrus mares, but more studies are required to ensure further embryo development and foaling.engAttribution 4.0 Internationalhttp://creativecommons.org/licenses/by/4.0/journal article1439-0531https://doi.org/10.1111/rda.1462239396857open access636.09Anoestrus recipientIn vitro embryoMareTransferVeterinaria3109 Ciencias Veterinarias