Tratamientos hormonales aplicados posterior a la IATF sobre la tasa de preñez y la viabilidad embrionaria en vacas de alta producción en estrés térmico
Tratamientos hormonales aplicados posterior a la IATF sobre la tasa de preñez y la viabilidad embrionaria en vacas de alta producción en estrés térmico
Authors
Gómez Marín, Yusep
Goicochea Vargas, José
Rondón Jorge, Wilson
Acosta Pachorro, Fidel
Montalvo Martin, Magaly
Pérez Saavedra, Marce
Ballarte Zevallos, Carlos
Silva Jiménez, Mauricio
Ratto Fuster, Marcelo
Goicochea Vargas, José
Rondón Jorge, Wilson
Acosta Pachorro, Fidel
Montalvo Martin, Magaly
Pérez Saavedra, Marce
Ballarte Zevallos, Carlos
Silva Jiménez, Mauricio
Ratto Fuster, Marcelo
Authors
Date
Datos de publicación:
10.15381/rivep.v30i4.17191
Keywords
Vacas de alta producción - GnRH - Tasa de preñez - Progesterona - Cuerpo lúteo
Collections
Abstract
El objetivo del estudio fue evaluar el efecto de GnRH, hCG y eCG aplicados 14 días
después de la inseminación artificial a tiempo (IATF) fijo sobre la tasa de preñez y
sobrevivencia embrionaria y fetal en vacas sometidas a estrés calórico. Las vacas (n=234)
fueron sincronizadas e inseminadas y recibieron diferentes dosis hormonales vía i.m. 14
días después: a) Grupo control: 2 ml de suero fisiológico (n=56), b) Grupo GnRH: 100 µg
de GnRH (n=58), Grupo c) hCG: 1500 UI de hCG (n=60), y d) Grupo eCG: 400 UI de eCG
(n=60). El diagnóstico de gestación y la evaluación del número de cuerpos lúteos (CL) se
determinó mediante ultrasonografía a los días 34, 45 y 60 de la IA. Las vacas tratadas con
GnRH presentaron una mayor tasa de preñez (p<0.05) y sin diferencias significativas
entre los demás grupos. La sobrevivencia embrionaria y fetal entre los días 45 y 60 fue
constante en todos los grupos, pero ocurrió una muerte fetal en el grupo eCG. No hubo
diferencia significativa en la proporción de cuerpos lúteos accesorios entre los grupos
tratados y el grupo control a los 60 días de gestación. Se concluye que la administración
de GnRH 14 días pos-IATF mejora la tasa de preñez en vacas lecheras sometidas a estrés
calórico.
The aim of this study was to evaluate the effect of GnRH, hCG and eCG applied 14 days after fixed time artificial insemination (FTAI) on the rate of pregnancy and embryonic and foetal survival in cows under heat stress. The cows (n = 234) were synchronized, inseminated and received 14 days later via i.m. the hormonal application: a) Control group: 2 ml of saline solution (n=56), b) GnRH group: 100 µg of GnRH (n=58), Group c) hCG: 1500 IU of hCG (n=60), and d) ECG Group: 400 IU of eCG (n=60). The diagnosis of pregnancy and the evaluation of the number of corpora lutea (CL) was determined by ultrasonography on days 34, 45 and 60 of the AI. Cows treated with GnRH had a higher pregnancy rate (p<0.05) and no significant differences were found between the other groups. Embryonic and foetal survival between days 45 and 60 was constant in all groups, but one foetal death occurred in the eCG group. There were no significant differences in the proportion of accessory CL between the treated groups and the control group at 60 days of gestation. It is concluded that the administration of GnRH 14 days post-FTAI improves the pregnancy rate in dairy cows under caloric stress.
The aim of this study was to evaluate the effect of GnRH, hCG and eCG applied 14 days after fixed time artificial insemination (FTAI) on the rate of pregnancy and embryonic and foetal survival in cows under heat stress. The cows (n = 234) were synchronized, inseminated and received 14 days later via i.m. the hormonal application: a) Control group: 2 ml of saline solution (n=56), b) GnRH group: 100 µg of GnRH (n=58), Group c) hCG: 1500 IU of hCG (n=60), and d) ECG Group: 400 IU of eCG (n=60). The diagnosis of pregnancy and the evaluation of the number of corpora lutea (CL) was determined by ultrasonography on days 34, 45 and 60 of the AI. Cows treated with GnRH had a higher pregnancy rate (p<0.05) and no significant differences were found between the other groups. Embryonic and foetal survival between days 45 and 60 was constant in all groups, but one foetal death occurred in the eCG group. There were no significant differences in the proportion of accessory CL between the treated groups and the control group at 60 days of gestation. It is concluded that the administration of GnRH 14 days post-FTAI improves the pregnancy rate in dairy cows under caloric stress.