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 | Acceso al texto completo restringido a Biblioteca INIA Las Brujas. Por información adicional contacte bibliolb@inia.org.uy. |
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Registro completo
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Biblioteca (s) : |
INIA Las Brujas; INIA Tacuarembó. |
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Fecha : |
21/10/2014 |
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Actualizado : |
11/10/2019 |
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Tipo de producción científica : |
Artículos en Revistas Indexadas Internacionales |
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Autor : |
PAGANONI, B.L.; FERGUSON, M.B.; FERRIO, S.; JONES, C.; KEARNEY, G.A.; KENYON, P.R.; MACLEAY, C.; VIÑOLES, C.; THOMPSON, A.N. |
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Afiliación : |
CAROLINA VIÑOLES GIL, Instituto Nacional de Investigación Agropecuaria (INIA), Uruguay. |
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Título : |
Early reproductive losses are a major factor contributing to the poor reproductive performance of Merino ewe lambs mated at 8-10 months of age. |
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Fecha de publicación : |
2014 |
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Fuente / Imprenta : |
Animal Production Science, 2014, v.54, no.6, p.762-772. |
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ISSN : |
1836-0939 |
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DOI : |
10.1071/AN13240 |
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Idioma : |
Inglés |
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Notas : |
Article history: Received 13 June 2013 / Accepted 26 February 2014 / Published online 9 April 2014. |
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Contenido : |
ABSTRACT.
The reproductive performance of Merino ewe lambs is lower than that achieved by mature ewes and is highly variable. It is likely that embryo loss represents a major source of reproductive wastage in Merino ewe lambs, but to our knowledge no studies have attempted to determine when the major reproductive losses occur or identify predisposing factors that are likely to lead to high rates of pregnancy failures in ewe lambs. After characterising where reproductive losses occurred in Merino ewe lambs mated at 8-10 months of age, we tested the hypothesis that pregnancy failure in ewe lambs is influenced by nutrition and liveweight change around conception and the genetic potential for growth of the ewe lamb. Two-hundred and twenty-four Merino ewe lambs born from 10 sires with Australian Sheep Breeding Values were teased for 14 days using vasectomised rams, and then fed two different diets for 68 days during mating. All ewe lambs were weighed and the appearance of crayon marks on their rump was recorded most days. Blood samples for progesterone assay were collected on Days 5, 12 and 17 after the first record of a crayon mark. Ultrasonography using a trans-rectal probe was used to measure the number of corpora lutea present, as a proxy for ovulation rate, 9 days after the first record of a crayon mark during the mating period. A further trans-rectal ultrasonography was undertaken 30 days after marking from the entire ram to determine pregnancy status and count the number of embryos. Over the entire mating period 54% of ewe lambs were pregnant with 66 fetuses per 100 ewes mated. The average ovulation rate was 150% however up to 84% of this potential was lost by weaning and the major contributor to this apparent deficit was the loss that occurred during the first 17 days after mating. Pregnancy failure was not significantly related to nutrition or liveweight change during mating however, there were significant differences in pregnancy failure between different sire groups. Pregnancy failure was significantly less for ewe lambs from sires with higher breeding values for weight and fat at post-weaning age (8-10 months). Only 60% of ewe lambs had achieved puberty when rams were introduced and only 83% by 35 days after mating. In addition, almost half of the ewe lambs that were mated for the first time during the first 35 days after rams were introduced, but failed to get pregnant, then seemed to skip a cycle or did not cycle again before the end of the 68-day mating period. Liveweight at introduction of entire rams was positively related to fertility, ovulation rate and reproductive rate. This study confirms that selection of sires with higher breeding values for post-weaning weight and fat will increase the fertility and reproductive rate of Merino ewe lambs mated at 8-10 months. This response is due in part to enhancing the onset of puberty and increasing the proportion of ewe lambs cycling at the start of mating and reducing pregnancy failure.
© CSIRO 2014. MenosABSTRACT.
The reproductive performance of Merino ewe lambs is lower than that achieved by mature ewes and is highly variable. It is likely that embryo loss represents a major source of reproductive wastage in Merino ewe lambs, but to our knowledge no studies have attempted to determine when the major reproductive losses occur or identify predisposing factors that are likely to lead to high rates of pregnancy failures in ewe lambs. After characterising where reproductive losses occurred in Merino ewe lambs mated at 8-10 months of age, we tested the hypothesis that pregnancy failure in ewe lambs is influenced by nutrition and liveweight change around conception and the genetic potential for growth of the ewe lamb. Two-hundred and twenty-four Merino ewe lambs born from 10 sires with Australian Sheep Breeding Values were teased for 14 days using vasectomised rams, and then fed two different diets for 68 days during mating. All ewe lambs were weighed and the appearance of crayon marks on their rump was recorded most days. Blood samples for progesterone assay were collected on Days 5, 12 and 17 after the first record of a crayon mark. Ultrasonography using a trans-rectal probe was used to measure the number of corpora lutea present, as a proxy for ovulation rate, 9 days after the first record of a crayon mark during the mating period. A further trans-rectal ultrasonography was undertaken 30 days after marking from the entire ram to determine pregnancy status and count the number ... Presentar Todo |
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Thesagro : |
COMPORTAMIENTO REPRODUCTIVO; CORDEROS; MERINO; OVINOS. |
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Asunto categoría : |
L01 Ganadería |
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Marc : |
LEADER 03985naa a2200301 a 4500
001 1051211
005 2019-10-11
008 2014 bl uuuu u00u1 u #d
022 $a1836-0939
024 7 $a10.1071/AN13240$2DOI
100 1 $aPAGANONI, B.L.
245 $aEarly reproductive losses are a major factor contributing to the poor reproductive performance of Merino ewe lambs mated at 8-10 months of age.$h[electronic resource]
260 $c2014
500 $aArticle history: Received 13 June 2013 / Accepted 26 February 2014 / Published online 9 April 2014.
520 $aABSTRACT. The reproductive performance of Merino ewe lambs is lower than that achieved by mature ewes and is highly variable. It is likely that embryo loss represents a major source of reproductive wastage in Merino ewe lambs, but to our knowledge no studies have attempted to determine when the major reproductive losses occur or identify predisposing factors that are likely to lead to high rates of pregnancy failures in ewe lambs. After characterising where reproductive losses occurred in Merino ewe lambs mated at 8-10 months of age, we tested the hypothesis that pregnancy failure in ewe lambs is influenced by nutrition and liveweight change around conception and the genetic potential for growth of the ewe lamb. Two-hundred and twenty-four Merino ewe lambs born from 10 sires with Australian Sheep Breeding Values were teased for 14 days using vasectomised rams, and then fed two different diets for 68 days during mating. All ewe lambs were weighed and the appearance of crayon marks on their rump was recorded most days. Blood samples for progesterone assay were collected on Days 5, 12 and 17 after the first record of a crayon mark. Ultrasonography using a trans-rectal probe was used to measure the number of corpora lutea present, as a proxy for ovulation rate, 9 days after the first record of a crayon mark during the mating period. A further trans-rectal ultrasonography was undertaken 30 days after marking from the entire ram to determine pregnancy status and count the number of embryos. Over the entire mating period 54% of ewe lambs were pregnant with 66 fetuses per 100 ewes mated. The average ovulation rate was 150% however up to 84% of this potential was lost by weaning and the major contributor to this apparent deficit was the loss that occurred during the first 17 days after mating. Pregnancy failure was not significantly related to nutrition or liveweight change during mating however, there were significant differences in pregnancy failure between different sire groups. Pregnancy failure was significantly less for ewe lambs from sires with higher breeding values for weight and fat at post-weaning age (8-10 months). Only 60% of ewe lambs had achieved puberty when rams were introduced and only 83% by 35 days after mating. In addition, almost half of the ewe lambs that were mated for the first time during the first 35 days after rams were introduced, but failed to get pregnant, then seemed to skip a cycle or did not cycle again before the end of the 68-day mating period. Liveweight at introduction of entire rams was positively related to fertility, ovulation rate and reproductive rate. This study confirms that selection of sires with higher breeding values for post-weaning weight and fat will increase the fertility and reproductive rate of Merino ewe lambs mated at 8-10 months. This response is due in part to enhancing the onset of puberty and increasing the proportion of ewe lambs cycling at the start of mating and reducing pregnancy failure. © CSIRO 2014.
650 $aCOMPORTAMIENTO REPRODUCTIVO
650 $aCORDEROS
650 $aMERINO
650 $aOVINOS
700 1 $aFERGUSON, M.B.
700 1 $aFERRIO, S.
700 1 $aJONES, C.
700 1 $aKEARNEY, G.A.
700 1 $aKENYON, P.R.
700 1 $aMACLEAY, C.
700 1 $aVIÑOLES, C.
700 1 $aTHOMPSON, A.N.
773 $tAnimal Production Science, 2014$gv.54, no.6, p.762-772.
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INIA Las Brujas (LB) |
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Registro completo
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Biblioteca (s) : |
INIA La Estanzuela; INIA Tacuarembó; INIA Treinta y Tres. |
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Fecha actual : |
02/04/2019 |
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Actualizado : |
26/06/2019 |
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Tipo de producción científica : |
Serie Técnica |
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Autor : |
VIÑOLES, C.; SANTA CRUZ TORRES, R. (Ed.). |
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Afiliación : |
CAROLINA VIÑOLES GIL, INIA (Instituto Nacional de Investigación Agropecuaria), Uruguay. Polo Agroforestal, UdelaR, EEBR, Cerro Largo.; RODRIGO SANTA CRUZ TORRES., Pasante Programa Nacional de Investigación Producción Carne y Lana, INIA Tacuarembó. Polo Agroforestal, UdelaR, EEBR, Cerro Largo. |
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Título : |
Recuento de folículos antrales y concentraciones de hormona anti-Mülleriana: dos potenciales herramientas de selección de reemplazos //Antral follicle count and anti-Müllerian hormone concentrations: two potential replacement selection tools. |
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Fecha de publicación : |
2019 |
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Fuente / Imprenta : |
Montevideo (UY): INIA, 2019. |
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Páginas : |
54 p. |
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Serie : |
(INIA Serie Técnica; 249) |
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ISBN : |
978-9974-38-420-0 |
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DOI : |
http://doi.org/10.35676/INIA/ST.249 |
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Idioma : |
Español |
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Notas : |
Consideraciones finales p. 51-52. |
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Contenido : |
Tabla de contenido: Índice de figuras. Índice de cuadros. Resumen. Abstract. 1. Introducción. Recría de vaquillonas: período determinante de su productividad futura. 2. Recuento folicular y fertilidad. Relación entre el recuento máximo de folículos antrales, las concentraciones de hormona anti-Mülleriana y la concepción en vaquillonas Hereford. 3. Reserva folicular y pubertad. El recuento de folículos antrales es una herramienta que permitiría seleccionar terneras más precoces al destete 4. Creep Feeding y recuento folicular. El Creep Feeding no afecta el recuento de folículos antrales al destete 5. Uso del recuento folicular a campo. Impacto del recuento de folículos antrales sobre la fertilidad de vaquillonas para carne 6. Programa recuento folicular automático. Detección de folículos en videos de ultrasonido de ovarios bovinos. 7. Consideraciones finales.
Resumen: La correcta selección de reemplazos es la clave del éxito reproductivo, ya que el momento en que ocurre la primera preñez marca la productividad y longevidad de la vaca en rodeo de cría. Para ello, es fundamental utilizar variables fenotípicas que se expresen temprano en la vida del animal, y tengan moderada heredabilidad. El recuento de folículos antrales (RFA) y las concentraciones de hormona anti-Mülleriana (AMH), son potenciales herramientas de selección que cumplen ambos criterios. En esta serie técnica, se describe una secuencia de experimentos que permitieron poner a punto metodologías inexistentes en Uruguay, simplificar
metodologías para su aplicación a campo y testar la hipótesis de que el RFA y la AMH pueden ser utilizadas para seleccionar vaquillonas al destete y pre-servicio con 14 y 24 meses de edad. Los resultados muestran que el RFA se relaciona con parámetros de crecimiento y desarrollo, y permitiría eliminar al destete vaquillonas Braford que alcanzan la pubertad más tarde. La alta correlación entre RFA y AMH sugiere que ambas herramientas podría utilizarse con el mismo objetivo. Las bajas concentraciones de progesterona en el ciclo pos-inseminación con 14 meses de edad en vaquillonas Braford con menor RFA, podría determinar una menor upervivencia embrionaria y preñez temprana. Vaquillonas Angus, Hereford y cruzas con bajo RFA pre-servicio con 24 meses de edad, conciben más tarde que vaquillonas con mayor RFA. Se requiere de ajustes metodológicos y un mayor número de experimentos utilizando más animales, para validar la efectividad de éstas herramientas de
selección de reemplazos. Abstract: The correct selection of replacements is the key to reproductive success, since the moment in which the first pregnancy occurs marks the productivity and longevity of the cow in the breeding herd. For this, it is essential to use phenotypic variables that are expressed early in the animal?s life, and have moderate heritability. The antral follicle count (AFC) and the concentrations of anti-Müllerian hormone (AMH) are potential selection tools that meet both
criteria. In this technical series, we describe a sequence of experiments that allowed us to develop non-existent methodologies in Uruguay, simplify methodologies for their application in the field and test the hypothesis that the AFC and AMH can be used to select heifers at weaning and service with 14 and 24 months of age. The results show that AFC is related to parameters of growth and development, and would allow to eliminate at weaning Braford heifers that reach puberty later. The high correlation between AFC and AMH suggests that both tools could be used for the same purpose. The low concentrations of progesterone in the post-insemination cycle with 14 months of age in Braford heifers with lower AFC, could determine a lower embryo survival and early pregnancy. Heifers Angus, Hereford and crosses with low AFC pre-service with 24 months of age, conceive later that heifers with greater AFC. Methodological adjustments and a greater number of experiments using more animals are required to validate the effectiveness of these replacement selection tools. MenosTabla de contenido: Índice de figuras. Índice de cuadros. Resumen. Abstract. 1. Introducción. Recría de vaquillonas: período determinante de su productividad futura. 2. Recuento folicular y fertilidad. Relación entre el recuento máximo de folículos antrales, las concentraciones de hormona anti-Mülleriana y la concepción en vaquillonas Hereford. 3. Reserva folicular y pubertad. El recuento de folículos antrales es una herramienta que permitiría seleccionar terneras más precoces al destete 4. Creep Feeding y recuento folicular. El Creep Feeding no afecta el recuento de folículos antrales al destete 5. Uso del recuento folicular a campo. Impacto del recuento de folículos antrales sobre la fertilidad de vaquillonas para carne 6. Programa recuento folicular automático. Detección de folículos en videos de ultrasonido de ovarios bovinos. 7. Consideraciones finales.
Resumen: La correcta selección de reemplazos es la clave del éxito reproductivo, ya que el momento en que ocurre la primera preñez marca la productividad y longevidad de la vaca en rodeo de cría. Para ello, es fundamental utilizar variables fenotípicas que se expresen temprano en la vida del animal, y tengan moderada heredabilidad. El recuento de folículos antrales (RFA) y las concentraciones de hormona anti-Mülleriana (AMH), son potenciales herramientas de selección que cumplen ambos criterios. En esta serie técnica, se describe una secuencia de experimentos que permitieron poner a punto metodologías inexistentes en Ur... Presentar Todo |
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Palabras claves : |
ANIMAL REPRODUCTION; CRECIMIENTO; FERTILIDAD; FERTILITY; GROWTH; PUBERTAD; PUBERTY; REPRODUCCIÓN ANIMAL; ULTRASONOGRAFÍA; ULTRASONOGRAPHY. |
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Asunto categoría : |
L01 Ganadería |
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URL : |
http://www.ainfo.inia.uy/digital/bitstream/item/12579/1/st-249-2019.pdf
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Marc : |
LEADER 05103nam a2200301 a 4500
001 1059673
005 2019-06-26
008 2019 bl uuuu u00u1 u #d
020 $a978-9974-38-420-0
024 7 $ahttp://doi.org/10.35676/INIA/ST.249$2DOI
100 1 $aVIÑOLES, C.
245 $aRecuento de folículos antrales y concentraciones de hormona anti-Mülleriana$bdos potenciales herramientas de selección de reemplazos //Antral follicle count and anti-Müllerian hormone concentrations: two potential replacement selection tools.
260 $aMontevideo (UY): INIA$c2019
300 $a54 p.
490 $a(INIA Serie Técnica; 249)
500 $aConsideraciones finales p. 51-52.
520 $aTabla de contenido: Índice de figuras. Índice de cuadros. Resumen. Abstract. 1. Introducción. Recría de vaquillonas: período determinante de su productividad futura. 2. Recuento folicular y fertilidad. Relación entre el recuento máximo de folículos antrales, las concentraciones de hormona anti-Mülleriana y la concepción en vaquillonas Hereford. 3. Reserva folicular y pubertad. El recuento de folículos antrales es una herramienta que permitiría seleccionar terneras más precoces al destete 4. Creep Feeding y recuento folicular. El Creep Feeding no afecta el recuento de folículos antrales al destete 5. Uso del recuento folicular a campo. Impacto del recuento de folículos antrales sobre la fertilidad de vaquillonas para carne 6. Programa recuento folicular automático. Detección de folículos en videos de ultrasonido de ovarios bovinos. 7. Consideraciones finales. Resumen: La correcta selección de reemplazos es la clave del éxito reproductivo, ya que el momento en que ocurre la primera preñez marca la productividad y longevidad de la vaca en rodeo de cría. Para ello, es fundamental utilizar variables fenotípicas que se expresen temprano en la vida del animal, y tengan moderada heredabilidad. El recuento de folículos antrales (RFA) y las concentraciones de hormona anti-Mülleriana (AMH), son potenciales herramientas de selección que cumplen ambos criterios. En esta serie técnica, se describe una secuencia de experimentos que permitieron poner a punto metodologías inexistentes en Uruguay, simplificar metodologías para su aplicación a campo y testar la hipótesis de que el RFA y la AMH pueden ser utilizadas para seleccionar vaquillonas al destete y pre-servicio con 14 y 24 meses de edad. Los resultados muestran que el RFA se relaciona con parámetros de crecimiento y desarrollo, y permitiría eliminar al destete vaquillonas Braford que alcanzan la pubertad más tarde. La alta correlación entre RFA y AMH sugiere que ambas herramientas podría utilizarse con el mismo objetivo. Las bajas concentraciones de progesterona en el ciclo pos-inseminación con 14 meses de edad en vaquillonas Braford con menor RFA, podría determinar una menor upervivencia embrionaria y preñez temprana. Vaquillonas Angus, Hereford y cruzas con bajo RFA pre-servicio con 24 meses de edad, conciben más tarde que vaquillonas con mayor RFA. Se requiere de ajustes metodológicos y un mayor número de experimentos utilizando más animales, para validar la efectividad de éstas herramientas de selección de reemplazos. Abstract: The correct selection of replacements is the key to reproductive success, since the moment in which the first pregnancy occurs marks the productivity and longevity of the cow in the breeding herd. For this, it is essential to use phenotypic variables that are expressed early in the animal?s life, and have moderate heritability. The antral follicle count (AFC) and the concentrations of anti-Müllerian hormone (AMH) are potential selection tools that meet both criteria. In this technical series, we describe a sequence of experiments that allowed us to develop non-existent methodologies in Uruguay, simplify methodologies for their application in the field and test the hypothesis that the AFC and AMH can be used to select heifers at weaning and service with 14 and 24 months of age. The results show that AFC is related to parameters of growth and development, and would allow to eliminate at weaning Braford heifers that reach puberty later. The high correlation between AFC and AMH suggests that both tools could be used for the same purpose. The low concentrations of progesterone in the post-insemination cycle with 14 months of age in Braford heifers with lower AFC, could determine a lower embryo survival and early pregnancy. Heifers Angus, Hereford and crosses with low AFC pre-service with 24 months of age, conceive later that heifers with greater AFC. Methodological adjustments and a greater number of experiments using more animals are required to validate the effectiveness of these replacement selection tools.
653 $aANIMAL REPRODUCTION
653 $aCRECIMIENTO
653 $aFERTILIDAD
653 $aFERTILITY
653 $aGROWTH
653 $aPUBERTAD
653 $aPUBERTY
653 $aREPRODUCCIÓN ANIMAL
653 $aULTRASONOGRAFÍA
653 $aULTRASONOGRAPHY
700 1 $aSANTA CRUZ TORRES, R.
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