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 | Acceso al texto completo restringido a Biblioteca INIA Treinta y Tres. Por información adicional contacte bibliott@inia.org.uy. |
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Registro completo
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Biblioteca (s) : |
INIA Treinta y Tres. |
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Fecha : |
19/05/2016 |
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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 : |
SINCLAIR, K.D.; MOLLE, G.; REVILLA, R.; ROCHE, J.F.; QUINTANS, G.; MORONGIU, L.; SANZ, A.; MACKEY, D.R.; DISKIN, M.G. |
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Afiliación : |
Stottish Agricultural College, Aberdeen.; Instituto Zootecnico e Caseaario per la Sardegna, Olmedo, Sardinia, Italy; Servicio de Investigación Agraria, Unidad de Producicón Animal, Zaragoza, Spain; Faculty Veterinary Medicine, Univerity college Dublin, Ireland.; GRACIELA QUINTANS ILARIA, INIA (Instituto Nacional de Investigación Agropecuaria), Uruguay. Scottish Agricultural College, Aberdeen; Instituto Zootecnico e Caseario per la Sardegna, Olmedo, Sardinia, Italy; Servicio de Investigación Agraria, Unidad de Producción Animal, Zaragoza, Spain; Faculty Veterinary Medicine, University College Dublin, Ireland. Teagasc, Athenry, Co. Galway, Ireland.; Teagasc, Athenry, Co. Galway, Ireland. |
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Título : |
Ovulation of the first dominant follicle arising after day 21 post partum in suckling beef cows. |
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Fecha de publicación : |
2002 |
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Fuente / Imprenta : |
Animal Science, 2002, v. 75, p. 115-126. |
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DOI : |
10.1017/S1357729800052899 |
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Idioma : |
Inglés |
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Notas : |
Article history: Received 8 December 2001 // Accepted 11 February 2002 // Published online 18 August 2016.
DOI: https://doi.org/10.1017/S1357729800052899 |
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Contenido : |
The effects of body condition score (BCS) of 2·0 or 3·0 units at calving (low v. moderate), post-partum energy intake at 0·6 or 1·0 MJ metabolizable energy (ME) per day per kg M0·75 (low v. high) and unrestricted or restricted (once daily) suckling on the ability of cows to ovulate were studied in a 2 ? 2 ? 2 factorial design with each treatment replicated eight times. Calf isolation and restricted suckling were imposed shortly after selection of the first dominant follicle (DF) to emerge after day 21 post partum. The episodic release of LH (sampled at 15-min intervals for 10 h) was determined 48 h before and 48 h after the day calf isolation and restricted suckling commenced. Additional blood samples were collected weekly for plasma insulin determination. The mean interval from calving to first ovulation was shorter for cows in moderate than low BCS at calving (47·8 v. 57·1 days, s.e.d. = 4·50, P < 0·05), and for cows suckling once daily than for those with unrestricted suckling (42·9 v. 62·0 days, s.e.d. = 4·50, P < 0·001). Post-partum nutrition did not affect this interval. Mean LH pulse frequency prior to the start of restricted suckling was higher for cows of moderate than low BCS at calving (3·2 v. 1·6 pulses per 10 h, s.e.d. = 0·60, P < 0·05). Subsequently, LH pulse frequency was higher for cows suckling once daily than for those with unrestricted suckling (4·0 v. 2·2 pulses per 10 h, s.e.d. = 0·82, P < 0·05). More cows in moderate than low BCS ovulated the first DF to emerge after day 21 post partum (within 4 to 6 days) in response to restricted suckling (69 v. 25%, P < 0·05). LH pulse frequency prior to restricted suckling increased (P < 0·05) with plasma insulin concentration (categorized as low, < 5; moderate, 5 to 8; and high, >8 mIU per l). There were indications of interactions between suckling treatment and BCS (P < 0·08), and suckling treatment and plasma insulin concentration (P < 0·06), on LH pulse frequency, which suggested that calf restriction could alleviate the suppressive effects of under nutrition on episodic LH release. Amongst cows suckling once daily, the non-ovulating animals had fewer LH pulses prior to restricted suckling and smaller, slower growing DF, indicating an inability of the DF to respond to increased LH pulse frequency following calf restriction. Cows of moderate BCS, particularly those with moderate to high levels of plasma insulin (³ 5 mIU per l), responded favourably to restricted suckling. In contrast, excessively thin cows with low plasma insulin concentrations (<5 mIU per l), that had most to gain from restricted suckling, responded poorly. MenosThe effects of body condition score (BCS) of 2·0 or 3·0 units at calving (low v. moderate), post-partum energy intake at 0·6 or 1·0 MJ metabolizable energy (ME) per day per kg M0·75 (low v. high) and unrestricted or restricted (once daily) suckling on the ability of cows to ovulate were studied in a 2 ? 2 ? 2 factorial design with each treatment replicated eight times. Calf isolation and restricted suckling were imposed shortly after selection of the first dominant follicle (DF) to emerge after day 21 post partum. The episodic release of LH (sampled at 15-min intervals for 10 h) was determined 48 h before and 48 h after the day calf isolation and restricted suckling commenced. Additional blood samples were collected weekly for plasma insulin determination. The mean interval from calving to first ovulation was shorter for cows in moderate than low BCS at calving (47·8 v. 57·1 days, s.e.d. = 4·50, P < 0·05), and for cows suckling once daily than for those with unrestricted suckling (42·9 v. 62·0 days, s.e.d. = 4·50, P < 0·001). Post-partum nutrition did not affect this interval. Mean LH pulse frequency prior to the start of restricted suckling was higher for cows of moderate than low BCS at calving (3·2 v. 1·6 pulses per 10 h, s.e.d. = 0·60, P < 0·05). Subsequently, LH pulse frequency was higher for cows suckling once daily than for those with unrestricted suckling (4·0 v. 2·2 pulses per 10 h, s.e.d. = 0·82, P < 0·05). More cows in moderate than low BCS ovulated the first DF t... Presentar Todo |
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Palabras claves : |
BEEF COWS; HORMONA LUTEINIZANTE; INSULIN; LH; NUTRICION; OVULATION; SUCKLING. |
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Thesagro : |
AMAMANTAMIENTO; BOVINOS DE CARNE; NUTRICION ANIMAL; OVULACION. |
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Asunto categoría : |
-- |
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Marc : |
LEADER 03789naa a2200373 a 4500
001 1054830
005 2019-10-11
008 2002 bl uuuu u00u1 u #d
024 7 $a10.1017/S1357729800052899$2DOI
100 1 $aSINCLAIR, K.D.
245 $aOvulation of the first dominant follicle arising after day 21 post partum in suckling beef cows.$h[electronic resource]
260 $c2002
500 $aArticle history: Received 8 December 2001 // Accepted 11 February 2002 // Published online 18 August 2016. DOI: https://doi.org/10.1017/S1357729800052899
520 $aThe effects of body condition score (BCS) of 2·0 or 3·0 units at calving (low v. moderate), post-partum energy intake at 0·6 or 1·0 MJ metabolizable energy (ME) per day per kg M0·75 (low v. high) and unrestricted or restricted (once daily) suckling on the ability of cows to ovulate were studied in a 2 ? 2 ? 2 factorial design with each treatment replicated eight times. Calf isolation and restricted suckling were imposed shortly after selection of the first dominant follicle (DF) to emerge after day 21 post partum. The episodic release of LH (sampled at 15-min intervals for 10 h) was determined 48 h before and 48 h after the day calf isolation and restricted suckling commenced. Additional blood samples were collected weekly for plasma insulin determination. The mean interval from calving to first ovulation was shorter for cows in moderate than low BCS at calving (47·8 v. 57·1 days, s.e.d. = 4·50, P < 0·05), and for cows suckling once daily than for those with unrestricted suckling (42·9 v. 62·0 days, s.e.d. = 4·50, P < 0·001). Post-partum nutrition did not affect this interval. Mean LH pulse frequency prior to the start of restricted suckling was higher for cows of moderate than low BCS at calving (3·2 v. 1·6 pulses per 10 h, s.e.d. = 0·60, P < 0·05). Subsequently, LH pulse frequency was higher for cows suckling once daily than for those with unrestricted suckling (4·0 v. 2·2 pulses per 10 h, s.e.d. = 0·82, P < 0·05). More cows in moderate than low BCS ovulated the first DF to emerge after day 21 post partum (within 4 to 6 days) in response to restricted suckling (69 v. 25%, P < 0·05). LH pulse frequency prior to restricted suckling increased (P < 0·05) with plasma insulin concentration (categorized as low, < 5; moderate, 5 to 8; and high, >8 mIU per l). There were indications of interactions between suckling treatment and BCS (P < 0·08), and suckling treatment and plasma insulin concentration (P < 0·06), on LH pulse frequency, which suggested that calf restriction could alleviate the suppressive effects of under nutrition on episodic LH release. Amongst cows suckling once daily, the non-ovulating animals had fewer LH pulses prior to restricted suckling and smaller, slower growing DF, indicating an inability of the DF to respond to increased LH pulse frequency following calf restriction. Cows of moderate BCS, particularly those with moderate to high levels of plasma insulin (³ 5 mIU per l), responded favourably to restricted suckling. In contrast, excessively thin cows with low plasma insulin concentrations (<5 mIU per l), that had most to gain from restricted suckling, responded poorly.
650 $aAMAMANTAMIENTO
650 $aBOVINOS DE CARNE
650 $aNUTRICION ANIMAL
650 $aOVULACION
653 $aBEEF COWS
653 $aHORMONA LUTEINIZANTE
653 $aINSULIN
653 $aLH
653 $aNUTRICION
653 $aOVULATION
653 $aSUCKLING
700 1 $aMOLLE, G.
700 1 $aREVILLA, R.
700 1 $aROCHE, J.F.
700 1 $aQUINTANS, G.
700 1 $aMORONGIU, L.
700 1 $aSANZ, A.
700 1 $aMACKEY, D.R.
700 1 $aDISKIN, M.G.
773 $tAnimal Science, 2002$gv. 75, p. 115-126.
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INIA Treinta y Tres (TT) |
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Registro completo
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Biblioteca (s) : |
INIA Treinta y Tres. |
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Fecha actual : |
18/04/2022 |
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Actualizado : |
18/04/2022 |
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Tipo de producción científica : |
Artículos en Revistas Indexadas Internacionales |
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Circulación / Nivel : |
Internacional - -- |
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Autor : |
LEZAMA, F.; PARUELO, J. |
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Afiliación : |
FELIPE LEZAMA, Department of Environmental Systems, Faculty of Agronomy, University of República, Montevideo, Uruguay.; JOSÉ PARUELO, Institute of Ecology and Environmental Sciences, Faculty of Sciences, UDELAR, UY. Department of Quantitative Methods and Information Systems, FAGRO, UY. INIA (Instituto Nacional de Investigación Agropecuaria), Uruguay. |
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Título : |
Regional assessment of stocking rate effects on uruguayan rangelands: a ranch-level study. |
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Fecha de publicación : |
2022 |
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Fuente / Imprenta : |
Rangeland Ecology & Management, 2022, volume 82, pages 58-65. Doi: https://doi.org/10.1016/j.rama.2022.02.005 |
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DOI : |
10.1016/j.rama.2022.02.005 |
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Idioma : |
Inglés |
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Notas : |
Article history: Received 27 April 2021 // Revised 9 February 2022 // Accepted 16 February 2022. |
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Contenido : |
We analyzed the variation of plant composition, forage production, and livestock diet across a broad stocking rate gradient on Eastern Hills rangelands of Uruguay. Our approach encompassed five ranches subjected to mixed sheep-cattle grazing and combined field surveys, microhistological fecal analysis, and remote sensing techniques. We hypothesized that selectivity would decrease as stocking rate increased. Vegetation data and fecal samples were obtained in 17 paddocks in 2008. To investigate the role of stocking rate on vegetation, we focused on dominant species and forage type cover. Diet composition was analyzed at forage type level. Annual net primary productivity was estimated for each paddock using the normalized difference vegetation index derived from the MODIS (Moderate Resolution Imaging Spectroradiometer) sensor. We found a clear relationship between the variation in stocking rate and floristic and forage type composition, both suggesting a deterioration of grassland conservation status. Cool season grass cover varied from 25% to 5%, from low to high stocking rates. Dicot cover showed an opposite trend, with values around 15% in the low and moderate stocking levels and reaching 35% on high-stocked paddocks. Diet composition and diet overlap between herbivores also showed clear patterns of response to stocking rate. On the other hand, livestock selectivity interacted with herbivore type. While cattle showed the expected pattern, sheep did not decrease selectivity in winter as stocking rate increased. Contrary to expectations, annual net primary productivity was similar across the different stocking rate levels and the month of maximum productivity was generally March. Our study provides strong evidence of marked rangeland degradation; however, the lack of response in terms of ANPP and the ability of sheep to maintain selectivity under high stocking rates could help to explain the lack of responsiveness in the adoption of generalized stocking adjustments by the ranchers. MenosWe analyzed the variation of plant composition, forage production, and livestock diet across a broad stocking rate gradient on Eastern Hills rangelands of Uruguay. Our approach encompassed five ranches subjected to mixed sheep-cattle grazing and combined field surveys, microhistological fecal analysis, and remote sensing techniques. We hypothesized that selectivity would decrease as stocking rate increased. Vegetation data and fecal samples were obtained in 17 paddocks in 2008. To investigate the role of stocking rate on vegetation, we focused on dominant species and forage type cover. Diet composition was analyzed at forage type level. Annual net primary productivity was estimated for each paddock using the normalized difference vegetation index derived from the MODIS (Moderate Resolution Imaging Spectroradiometer) sensor. We found a clear relationship between the variation in stocking rate and floristic and forage type composition, both suggesting a deterioration of grassland conservation status. Cool season grass cover varied from 25% to 5%, from low to high stocking rates. Dicot cover showed an opposite trend, with values around 15% in the low and moderate stocking levels and reaching 35% on high-stocked paddocks. Diet composition and diet overlap between herbivores also showed clear patterns of response to stocking rate. On the other hand, livestock selectivity interacted with herbivore type. While cattle showed the expected pattern, sheep did not decrease selectivity i... Presentar Todo |
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Palabras claves : |
(NDVI); EASTERN HILLS; FORAGE TYPES; LIVESTOCK DIET; MICROHISTOLOGICAL TECHNIQUE; NORMALIZED DIFFERENCE VEGETATION INDEX; PLANT COMPOSITION. |
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Asunto categoría : |
F40 Ecología vegetal |
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Marc : |
LEADER 02892naa a2200241 a 4500
001 1063033
005 2022-04-18
008 2022 bl uuuu u00u1 u #d
024 7 $a10.1016/j.rama.2022.02.005$2DOI
100 1 $aLEZAMA, F.
245 $aRegional assessment of stocking rate effects on uruguayan rangelands$ba ranch-level study.$h[electronic resource]
260 $c2022
500 $aArticle history: Received 27 April 2021 // Revised 9 February 2022 // Accepted 16 February 2022.
520 $aWe analyzed the variation of plant composition, forage production, and livestock diet across a broad stocking rate gradient on Eastern Hills rangelands of Uruguay. Our approach encompassed five ranches subjected to mixed sheep-cattle grazing and combined field surveys, microhistological fecal analysis, and remote sensing techniques. We hypothesized that selectivity would decrease as stocking rate increased. Vegetation data and fecal samples were obtained in 17 paddocks in 2008. To investigate the role of stocking rate on vegetation, we focused on dominant species and forage type cover. Diet composition was analyzed at forage type level. Annual net primary productivity was estimated for each paddock using the normalized difference vegetation index derived from the MODIS (Moderate Resolution Imaging Spectroradiometer) sensor. We found a clear relationship between the variation in stocking rate and floristic and forage type composition, both suggesting a deterioration of grassland conservation status. Cool season grass cover varied from 25% to 5%, from low to high stocking rates. Dicot cover showed an opposite trend, with values around 15% in the low and moderate stocking levels and reaching 35% on high-stocked paddocks. Diet composition and diet overlap between herbivores also showed clear patterns of response to stocking rate. On the other hand, livestock selectivity interacted with herbivore type. While cattle showed the expected pattern, sheep did not decrease selectivity in winter as stocking rate increased. Contrary to expectations, annual net primary productivity was similar across the different stocking rate levels and the month of maximum productivity was generally March. Our study provides strong evidence of marked rangeland degradation; however, the lack of response in terms of ANPP and the ability of sheep to maintain selectivity under high stocking rates could help to explain the lack of responsiveness in the adoption of generalized stocking adjustments by the ranchers.
653 $a(NDVI)
653 $aEASTERN HILLS
653 $aFORAGE TYPES
653 $aLIVESTOCK DIET
653 $aMICROHISTOLOGICAL TECHNIQUE
653 $aNORMALIZED DIFFERENCE VEGETATION INDEX
653 $aPLANT COMPOSITION
700 1 $aPARUELO, J.
773 $tRangeland Ecology & Management, 2022, volume 82, pages 58-65. Doi: https://doi.org/10.1016/j.rama.2022.02.005
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