Fecha/hora: 16/06/2024 08:52:07

Biblioteca(s): | INIA Las Brujas.
Fecha corriente: | 04/11/2022
Fecha de la última actualización: | 07/11/2022
Autoria: | ARAGUNDE VIEYTES, R.; VIÑOLES, C.; GASTAL, G.D.A.; CAVESTANY, D.
Afiliación: | RAFAEL ARAGUNDE VIEYTES, Facultad de Veterinaria, Universidad de la Republica, Ruta 1, km 42.5, Montevideo, Uruguay; CAROLINA VIÑOLES GIL, Centro de Salud Reproductiva de Rumiantes en Sistemas Agroforestales, Casa de la Universidad de Cerro Largo, UdelaR, Ruta 26, km 408, Cerro Largo, Uruguay; GUSTAVO DESIRE ANTUNES GASTAL, INIA (Instituto Nacional de Investigación Agropecuaria), Uruguay; DANIEL CAVESTANY, Facultad de Veterinaria, Universidad de la Republica, Ruta 1, km 42.5, Montevideo, Uruguay.
Título: | Equine chorionic gonadotropin administered on day 5 of a 7-days fixed-time artificial insemination program improves ovulation synchrony and corpus luteum function in anestrous beef cows
Año de publicación: | 2022
Fuente/Imprenta: | Theriogenology, January 2023, Volume 195, Pages 62-68. doi: https://doi.org/10.1016/j.theriogenology.2022.10.016
ISSN: | 0093-691X
DOI: | 10.1016/j.theriogenology.2022.10.016
Idioma: | Inglés

Notas:

Article history: Received 17 June 2022; Received in revised form 5 October 2022; Accepted 12 October 2022; Available online 17 October 2022.
Correspondence authors:  Gastal, G.D.A.; Ruta 11, Km 50, Colonia del Sacramento, Colonia, Uruguay; email:ggastal@inia.org.uy  --   Aragunde Vieytes, R.; Facultad de Veterinaria, UDELAR, Ruta 1, km 42.5, Montevideo, Uruguay; email:rafaelaragunde@fvet.edu.uy  --

Contenido: | ABSTRACT.- In order to assess the effect of equine chorionic gonadotropin (eCG) administered on Day 5 or 7 of a fixed-time artificial insemination protocol (FTAI) in anestrous suckled beef cows, two experiments were performed to determine the following endpoints: Experiment 1 (n = 22), preovulatory follicle (POF) diameter, ovulation time, corpus luteum (CL) area, estradiol (E2) and progesterone (P4) concentrations; and Experiment 2 (n = 676), a field trial to evaluate conception rate using the same experimental design. In both experiments, a synchronization protocol using estradiol benzoate (EB) (Day 0), intravaginal progestin device (IVD) (Days 0 through 7), prostaglandin (PGF) (Day 7), eCG (Day 5 or 7), and GnRH (Day 9). Treatment consisted of administering 400 IU of eCG on Day 5 (T5) or Day 7 (T7 or control) concomitant with treatment with PGF2&#945;. In experiment 1, all cows of T5 ovulated by 16 h after GnRH administration. The POF tended (P = 0.06; P = 0.07) to be larger at 1 and 2 d before ovulation in T5. The day before ovulation, E2 tended to be lower (P = 0.06) in T5 compared with T7. The CL area and the P4 concentrations were greater (P = 0.04) on day 9 in T5 compared with T7. In experiment 2, the conception rate was greater (P = 0.04) in T5 (72.2%) compared with T7 (61.0%) group. Therefore, administration of eCG on Day 5 of the designed protocol hastened ovulation of a greater follicle, which produced a larger CL and greater concentrations of progesterone by Day 9 after ovulation, resulting in 11.2% increase in cows pregnant. © 2022 Elsevier Inc.
Palabras-Clave: | Anestrous; Corpus luteum; Equine chorionic gonadotropin; Ovulation; PLATAFORMA DE INVESTIGACIÓN EN SALUD ANIMAL; Postpartum; Preovulatory follicle.
Categoría del tema: | --
Registro original: | INIA Las Brujas (LB)
Ejemplares: | LB - (103223-1) - PXI - AP - DD - PP/Theriogenology/2022 -  -  - DIS