Fecha/hora: 16/06/2024 05:39:19

Biblioteca(s): 	INIA Las Brujas.	
Fecha corriente: 	07/11/2022	
Fecha de la última actualización: 	07/11/2022	
Autoria: 	DUVAL, L.H.; RECHSTEINER, S.M.F.; GASTAL, G.D.A.; GASTAL, M.O.; MATTOS, R.C.; GASTAL, E.L.	
Afiliación: 	LUZIA H. DUVAL, Postgraduate Program in Animal Medicine: Equine, Faculty of Veterinary Medicine, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil; SANDRA M. FIALA RECHSTEINER, Postgraduate Program in Animal Medicine: Equine, Faculty of Veterinary Medicine, Federal University Rio Grande do Sul, Rio Grande do Sul, Porto Alegre, Brazil; HISTOREP, Biology Institute, Federal University of Pelotas, Rio Grande do Sul, Pelotas, Brazi; GUSTAVO DESIRE ANTUNES GASTAL, INIA (Instituto Nacional de Investigación Agropecuaria), Uruguay; MELBA O. GASTAL, Animal Science, School of Agricultural Sciences, Southern Illinois University, Carbondale, IL, United States; RODRIGO C. MATTOS, Postgraduate Program in Animal Medicine: Equine, Faculty of Veterinary Medicine, Federal University of Rio Grande do Sul, Rio Grande do Sul, Porto Alegre, Brazil; EDUARDO L. GASTAL, Animal Science, School of Agricultural Sciences, Southern Illinois University, Carbondale, IL, United States.	
Título: 	Ovarian and uterine dynamics during the estrous cycle in Criollo breed mares.	
Año de publicación: 	2022	
Fuente/Imprenta: 	Journal of Equine Veterinary Science, 2022, Volume 118,  Article 104131. doi: https://doi.org/10.1016/j.jevs.2022.104131	
ISSN: 	0737-0806	
DOI: 	10.1016/j.jevs.2022.104131	
Idioma: 	Inglés	
Notas: 	Article history: Received 12 July 2022; Received in revised form 16 September 2022; Accepted 26 September 2022; Available online 29 September 2022. 
Correspondence author:  Gastal, E.L.; Animal Science, School of Agricultural Sciences, Southern Illinois University, 1205 Lincoln Drive, MC 4417, Carbondale, IL, United States; email:egastal@siu.edu  --	
Contenido: 	ABSTRACT.- After having been brought to America 400 years ago, the Criollo horse reproduced freely for centuries in the southern part of the American continent. Roughness, resistance, and endurance are typical characteristics of this breed of horses. Although the natural selection that occurred over the centuries may have positively influenced the fertility and longevity of this breed, information regarding ovarian function and other reproductive aspects of Criollo breed mares under natural or controlled management conditions is scarce. The objectives of the present study were to (1) characterize the follicular dynamics of Criollo breed mares, (2) characterize growth and regression of the corpus luteum, and (3) study the cervical and uterine tone and ultrasonographic echotexture changes during two consecutive estrous cycles. In this study, 26 interovulatory intervals (IOI) were evaluated in 13 mares. Spontaneous estrous cycles were characterized by the following: (1) the IOI length was 21 days; (2) dominant and subordinate follicles emerged together at day 5 (ovulation = day 0), and their growth rates were slower until the day of deviation; (3) the deviation in growth rates between the two largest follicles of the ovulatory wave occurred when the dominant and subordinate follicles reached 22 and 21 mm in diameter, respectively; (4) the mean diameter of the preovulatory follicle at the day before ovulation was 43 mm; (5) different combinations of follicular waves were observed in each interovulatory interval; (6) the corpus luteum reached its maximum diameter about 2 days after ovulation and decreased gradually afterward; (7) after ovulation, the cervical and uterine tones were positively correlated and remained elevated until the onset of the expected luteolysis (days 12?14); and (8) after the expected luteolysis, the endometrial echotexture started to increase and reached maximum values 5?3 days before ovulation, when it started to decrease. Moderate-to-strong positive correlations between IOIs revealed repeatability within animals for the diameter of the preovulatory follicle at maximum and at the day before ovulation, cervical and uterine tones, endometrial echotexture, and corpus luteum diameter. The findings herein presented are of fundamental importance for a better understanding of the reproductive physiological patterns of the estrous cycle in the Criollo breed mare. © 2022 Elsevier Inc.	
Palabras-Clave: 	Cervix and uterus; Follicle and corpus luteum dynamics; Horse; Ultrasound.	
Categoría del tema: 	L10 Genética y mejoramiento animal	
Registro original: 	INIA Las Brujas (LB)	
Ejemplares: 	LB - (103224-1) - PXI - AP - DD - PP/Jr.Equine Veterinary Science/2022 -  -  - DIS