Avaliação da reutilização do implante de progesterona em búfalas submetidas a protocolo curto de IATF na Amazônia

Abstract

This study aimed to evaluate whether the reuse of progesterone (P4) implants was able to synchronize the follicular development wave in buffalos in a short IATF protocol. New progesterone (P4) implants of 2,0g (G1) and previously used for 7 (G2), 14 (G3), 21 (G4) and 28 (G5) days were used. The time of use of P4 implants was considered as experimental treatments. The reuse of P4 implants did not affect (P > 0.05) the diameter and area of the preovulatory follicle, diameter and area of CL, ovulation rates, synchronization rate, and follicular growth rate. Treatments G1, G2 and G4 showed signs of being harmful by inducing higher rates of follicular cyst formation in buffaloes when compared to groups G3 and G5.The use of P4 devices previously used for up to 28 days in a short IATF protocol was able to induce concentrations >1 ng/mL during exposure to P4, preventing ovulations in this period of buffalos created under the Brazilian equatorial region. However, there are indications that concentrations above 1.5 ng/mL may be the cause of the high incidence of follicular cysts identified in the experimental groups. Thus, it is concluded that the use of the 7d protocol with P4 implants with low P4 concentration in buffaloes synchronized the follicular wave more efficiently.