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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. |
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Fecha actual : |
23/09/2014 |
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Actualizado : |
05/11/2019 |
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Tipo de producción científica : |
Artículos en Revistas Indexadas Internacionales |
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Circulación / Nivel : |
A - 2 |
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Autor : |
FIERRO, S.; GIL, J.; VIÑOLES, C.; SOCA, F.; BANCHERO, G.; OLIVERA-MUSANTE, J. |
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Afiliación : |
CAROLINA VIÑOLES GIL, Instituto Nacional de Investigación Agropecuaria (INIA), Uruguay; GEORGGET ELIZABETH BANCHERO HUNZIKER, Instituto Nacional de Investigación Agropecuaria (INIA), Uruguay. |
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Título : |
Protein supplementation during a short-interval prostaglandin-based protocol for timed AI in sheep. |
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Fecha de publicación : |
2014 |
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Fuente / Imprenta : |
Animal Reproduction Science, october 2014, Volume 149, Issues 3?4, Pages 158-162. |
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ISSN : |
0378-4320 |
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DOI : |
10.1016/j.anireprosci.2014.07.009 |
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Idioma : |
Inglés |
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Notas : |
Article history:Received 8 November 2013/Received in revised form 2 July 2014/Accepted 8 July 2014/Available online 18 July 2014. |
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Contenido : |
The aim of this experiment was to improve the reproductive performance of a short-interval prostaglandin (PG)-based protocol for timed artificial insemination in sheep, using a short-term nutritional treatment. During the breeding season (March–April), 132 multiparous and 61 nulliparous Corriedale ewes grazing natural pastures (600 kg DM/ha, 8.5% CP), were allocated to two groups: 1, Control group (n = 100) two injections of D-Cloprostenol (75 ?g per dose, 7 d apart: Synchrovine® protocol); and 2, Supplemented group (n = 93) ewes in which stage of the oestrous cycle was synchronised with Synchrovine® protocol plus focus feeding of a protein supplement (33.8% CP) between PG doses (Day ?7 to ?2). Cervical AI was performed at fixed time (Day 0), 46 ± 1.0 h after the second PG injection using 150 million sperm per ewe. Ovulation rate (Day 10), pregnancy rate, prolificacy and fecundity at Day 69 were evaluated by ultrasonography. Ovulation rate at Day 10 (1.20 ± 0.05 vs. 1.22 ± 0.05), pregnancy (46 ± 0.05 vs. 56 ± 0.05), prolificacy (1.09 ± 0.04 vs. 1.06 ± 0.05), and fecundity (0.49 ± 0.06 vs. 0.59 ± 0.06) at Day 69, were similar between groups (P > 0.05; Control and Supplemented group respectively). It is concluded that focus feeding for 6 d with protein supplementation during a short-interval PG-based protocol (Synchrovine®) did not improve the reproductive outcome associated with this protocol. |
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Palabras claves : |
EWES; FOCUS FEEDING; INSEMINACIÓN ARTIFICIAL; OESTRUS SYNCHRONISATION; OVEJA; OVULATION RATE; PROSTAGLANDIN; SUPLEMENTACIÓN PROTEICA; TIMED ARTIFICIAL INEMINATION; TIMED ARTIFICIAL INSEMINATION. |
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Thesagro : |
INSEMINACIÓN ARTIFICIAL; OVEJA; REPRODUCCION OVINA; SUPLEMENTACION. |
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Asunto categoría : |
L53 Fisiología Animal - Reproducción |
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Marc : |
LEADER 02700naa a2200385 a 4500
001 1050468
005 2019-11-05
008 2014 bl uuuu u00u1 u #d
022 $a0378-4320
024 7 $a10.1016/j.anireprosci.2014.07.009$2DOI
100 1 $aFIERRO, S.
245 $aProtein supplementation during a short-interval prostaglandin-based protocol for timed AI in sheep.$h[electronic resource]
260 $c2014
500 $aArticle history:Received 8 November 2013/Received in revised form 2 July 2014/Accepted 8 July 2014/Available online 18 July 2014.
520 $aThe aim of this experiment was to improve the reproductive performance of a short-interval prostaglandin (PG)-based protocol for timed artificial insemination in sheep, using a short-term nutritional treatment. During the breeding season (March–April), 132 multiparous and 61 nulliparous Corriedale ewes grazing natural pastures (600 kg DM/ha, 8.5% CP), were allocated to two groups: 1, Control group (n = 100) two injections of D-Cloprostenol (75 ?g per dose, 7 d apart: Synchrovine® protocol); and 2, Supplemented group (n = 93) ewes in which stage of the oestrous cycle was synchronised with Synchrovine® protocol plus focus feeding of a protein supplement (33.8% CP) between PG doses (Day ?7 to ?2). Cervical AI was performed at fixed time (Day 0), 46 ± 1.0 h after the second PG injection using 150 million sperm per ewe. Ovulation rate (Day 10), pregnancy rate, prolificacy and fecundity at Day 69 were evaluated by ultrasonography. Ovulation rate at Day 10 (1.20 ± 0.05 vs. 1.22 ± 0.05), pregnancy (46 ± 0.05 vs. 56 ± 0.05), prolificacy (1.09 ± 0.04 vs. 1.06 ± 0.05), and fecundity (0.49 ± 0.06 vs. 0.59 ± 0.06) at Day 69, were similar between groups (P > 0.05; Control and Supplemented group respectively). It is concluded that focus feeding for 6 d with protein supplementation during a short-interval PG-based protocol (Synchrovine®) did not improve the reproductive outcome associated with this protocol.
650 $aINSEMINACIÓN ARTIFICIAL
650 $aOVEJA
650 $aREPRODUCCION OVINA
650 $aSUPLEMENTACION
653 $aEWES
653 $aFOCUS FEEDING
653 $aINSEMINACIÓN ARTIFICIAL
653 $aOESTRUS SYNCHRONISATION
653 $aOVEJA
653 $aOVULATION RATE
653 $aPROSTAGLANDIN
653 $aSUPLEMENTACIÓN PROTEICA
653 $aTIMED ARTIFICIAL INEMINATION
653 $aTIMED ARTIFICIAL INSEMINATION
700 1 $aGIL, J.
700 1 $aVIÑOLES, C.
700 1 $aSOCA, F.
700 1 $aBANCHERO, G.
700 1 $aOLIVERA-MUSANTE, J.
773 $tAnimal Reproduction Science, october 2014, Volume 149, Issues 3?4, Pages 158-162.
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