Título

La administración de progesterona reduce la presentación de ciclos cortos sin disminuir la fertilidad en cabras anéstricas expuestas a machos cabríos foto-estimulados

Autor

DORA MARIA CORTINAS REYES

Colaborador

GERARDO DUARTE MORENO (Asesor de tesis)

JOSÉ ALBERTO DELGADILLO SÁNCHEZ (Asesor de tesis)

JOSÉ ALFREDO FLORES CABRERA (Asesor de tesis)

HORACIO HERNÁNDEZ HERNÁNDEZ (Asesor de tesis)

JESÚS VIELMA SIFUENTES (Asesor de tesis)

Nivel de Acceso

Acceso Abierto

Resumen o descripción

"El objetivo fue determinar si la administración de progesterona previa al efecto macho, reduce la incidencia de ciclos cortos sin disminuir la fertilidad en cabras anéstricas. Se utilizaron 53 cabras multíparas, distribuidos en 3 grupos. Un control (GC, n=17) no recibió tratamiento hormonal, otro se le administró 20 mg de progesterona 48 h antes de la introducción del macho (G48h; n=18), a otro se le aplicó la misma dosis antes de la introducción del macho (G0h; n=18). Se utilizaron 8 machos intactos y 3 vasectomizados adultos, sometidos a un tratamiento fotoperiódico de días largos. El semen de los machos intactos se procesó y aplicó a las cabras en estro. La mayoría de las cabras presentaron actividad estral (>80%) no difiriendo entre grupos (P>0.05). La latencia al primer estro fue menor en el G48h (41.6 ± 4.1 h) que en el G0h (70.2 ± 1.7 h; P<0.05); no existiendo diferencia entre el G48h y el GC (52.8 ± 8.8 h; P>0.05). El porcentaje de hembras que presentaron ciclos cortos fue menor en el G48h (17.6 %) y el G0h (33.3 %) que en el GC (88.2%; P<0.05). La duración del primero y segundo estro no difirió entre grupos (P>0.05). La tasa ovulatoria no difirió entre G48h, G0h y GC (1.9 ± 0.2, 1.9 ± 0.2 y 1.5 ± 0.1, respectivamente; P>0.05). La tasa de gestación no difirió entre G48h, G0h y GC (75%, 76% y 73%, respectivamente; P>0.05). Concluyendo que la administración de progesterona reduce la presentación de ciclos estrales cortos sin disminuir la fertilidad en cabras anéstricas expuestas a machos cabríos foto-estimulados."

"The aim of this study was to determine if the administration of progesterone prior to the introduction of males reduces the incidence of short cycles without decreasing fertility in anestrous goats exposed to photo-stimulated bucks inseminated with fresh semen. This study was performed in March and April. We used 53 multiparous goats and eleven bucks subjected to a treatment of long days (16 h of light) from November 1st to January 15th (3 vasectomized bucks and 8 intact bucks). Goats were divided in 3 groups; the control group did not receive progesterone treatment prior to the exposition to photo-stimulated buck (GC; n=17). A second group of females received 20 mg of progesterone IM 48 h before male introduction (G48h; n=18) and a third group received the same dose of progesterone at male introduction (G0h; n=18). Vasectomized bucks were introduced in each group of goats and they were exchanged between groups every 12 h. Estrous behavior was detected in the morning and afternoon during 30 min for 10 days. The semen of 8 intact males was collected depending on the presence of goats in estrus. Each ejaculate was evaluated, diluted and stored in 0.25 ml straws. Females detected in estrous in the morning were inseminated in the afternoon and females detected in estrous in the afternoon were inseminated the next day in the morning. In all groups, most of goats displayed estrous behavior (>80%) and there was no difference between groups. The latency to first estrous was lower in the G48h (41.6 ± 4.1) than G0h (70.2 ± 1.7; P<0.05); however, no differences were observed between G48h and GC (52.8 ± 8.8 h; P>0.05). The porcentage of females displayed short cycles was lower in the G48h (17.6%) and G0h (33.3%) than GC (88.2 %; P<0.05). The durations of the first and second estrus were not different between groups (P>0.05). The ovulation rates were not different between the G48h, G0h and GC (1.9 ± 0.2, 1.9 ± 0.2 and 1.5 ± 0.1, respectively; P>0.05). The pregnancy rates were not different between G48h, G0h and GC (75%, 76% and 73%; respectively; P>0.05). We concluded that the administration of progesterone prior to the introduction of photo-estimulated males reduces the incidence of short cycles without decreasing fertility in anestrous goats inseminated with fresh semen."

Fecha de publicación

1 de junio de 2015

Tipo de publicación

Tesis de doctorado

Versión de la publicación

Versión publicada

Formato

application/pdf

Idioma

Español

Audiencia

Estudiantes

Investigadores

Repositorio Orígen

Repositorio Digital CID-UAAAN

Descargas

481

Comentarios



Necesitas iniciar sesión o registrarte para comentar.