Fecha/hora: 03/06/2024 07:37:01

Biblioteca(s): 	INIA La Estanzuela; INIA Las Brujas.	
Fecha corriente: 	21/02/2014	
Fecha de la última actualización: 	14/10/2019	
Autoria: 	FIERRO, S.; OLIVERA-MUZANTEA, J.; GIL, J.; VIÑOLES, C.	
Afiliación: 	CAROLINA VIÑOLES GIL, Instituto Nacional de Investigación Agropecuaria (INIA), Uruguay.	
Título: 	Effects of prostaglandin administration on ovarian follicular dynamics, conception, prolificacy, and fecundity in sheep.	
Año de publicación: 	2011	
Fuente/Imprenta: 	Theriogenology, 2011, v.76, no.4, p.630-639.	
ISSN: 	0093-691X	
DOI: 	10.1016/j.theriogenology.2011.03.016	
Idioma: 	Español
Inglés	
Notas: 	Article history: Received 23 August 2010 / Received in revised form 17 March 201 / Accepted 18 March 2011.	
Contenido: 	ABSTRACT.

Two experiments were conducted to determine the effects of prostaglandin administration on ovarian follicular dynamics, conception, prolificacy, and fecundity in sheep. During the breeding season, multiparous Corriedale ewes were randomly allocated to two groups: 1) PG group (n = 15 and n = 135 in Experiments I and II, respectively): synchronized with two injections of DL-Cloprostenol (125 &#956;g) given 7 d apart, and inseminated at a fixed time (Day 0), 48 h after the second injection; and 2) Control group (n = 15 and n = 73 in Experiments I and II): ewes in spontaneous estrus inseminated at detected estrus. Ewes received 100 10 6 sperm by intrauterine AI. Ultrasonography was used to evaluate growth of the ovulatory follicle, ovulation rate (OR), conception rate, and prolificacy on Days 30 and 60. Ewes from the group PG had a larger (4.8 0.5 mm, mean SEM; P &lt; 0.05) ovulatory follicle that grew faster (1.2 0.3 mm/d, P = 0.08), and a lower OR (1.37 0.1, P &lt; 0.05), compared to ewes from the Control group (3.9 0.2 mm, 0.7 0.2 mm/d, and 1.61 0.1 respectively). Plasma progesterone concentrations from Days -6 to 1 were lower in the PG group (P &lt; 0.05), but plasma estradiol concentrations were similar between groups (P &gt; 0.05). Progesterone concentrations were similar between groups during the early luteal phase and on Days 12 and 17 (P &gt; 0.05). The embryo recovery rate (Day 7) tended to be lower in the PG group (39 vs 64%, P = 0.08), but embryo quality did not differ between groups. Conception, prolificacy and fecundity, were lower in the PG than in the Control group (P &lt; 0.05). Cumulative reproductive losses were similar between groups, but more twins were lost in the PG group (P &lt; 0.05). We concluded that in ewes synchronized with PGF 2&#945; given twice, 7 d apart, lower reproductive performance was associated with an environment dominated by lower progesterone concentrations that stimulated the preovulatory follicle to grow faster and become larger; this was associated with lower rates of ovulation, conception, prolificacy, and fecundity. 
© 2011 Elsevier Inc.	
Palabras-Clave: 	PÉRDIDA DE EMBRIONES.	
Thesagro: 	COMPORTAMIENTO REPRODUCTIVO; INSEMINACIÓN EN OVINOS; OVINOS.	
Categoría del tema: 	--
L53 Fisiología Animal - Reproducción	
Registro original: 	INIA Las Brujas (LB)	
Ejemplares: 	LB - (12822-1) - PXI - AP - PP - PP/THERIOGENOLOGY/2011 -  - . - DIS