Año-Perello, AinaSantos Jiménez, ZurisadayEncinas Cerezo, María TeresaMartínez-Ros, PaulaGonzález Bulnes, Antonio2023-06-172023-06-172020-07-162076-261510.3390/ani10071208https://hdl.handle.net/20.500.14352/8357The present study aimed to set up a short-term protocol for synchronization of follicular wave emergence in sheep, concomitant with estrus synchronization, which would improve ovarian response in assisted reproductive technologies. Administration of a single GnRH dose, concomitant with the insertion of a progesterone-loaded CIDR device, caused regression of gonadotrophin-dependent follicles ≥4 mm in all the GnRH-treated sheep and in around 80% of the controls treated only with CIDR (p < 0.05). Similar percentages of ewes lost all follicles (around 70%) or only the largest one (around 30%) in both groups. Hence, 54.1% and 70% of the sheep lost all large follicles and initiated a new follicular wave in the control and GnRH groups, respectively (p < 0.05). The remaining sheep showed follicles that were still not dependent of luteinizing hormone (LH). So, in fact, all the sheep had non-dominant follicles after treatment. In conclusion, a treatment including GnRH at CIDR insertion would offer a time- and cost-efficient protocol for inducing follicular turnover and synchronizing a new follicular wave at any stage of the estrous cycle.engAtribución 3.0 Españajournal articlehttps://doi.org/10.3390/ani10071208https://www.mdpi.com/2076-2615/10/7/1208open accessAssisted reproductionestrus synchronizationfollicleGnRHsheepGanado ovinoObstetricia veterinaria