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Registro Completo |
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Biblioteca(s): |
Embrapa Caprinos e Ovinos. |
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Data corrente: |
19/09/2017 |
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Data da última atualização: |
19/09/2017 |
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Autoria: |
JACOBSON, D. R.; LINDAHL, I. L.; MCNEILL, J. J.; SHAW, J. C.; DOETSCH, R. N.; DAVIS, R. E. |
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Título: |
Feedlot bloat studies. III. Rumen fatty acids and metabolic activity of rumen bacteria of animals placed on a bloat-producing diet. |
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Ano de publicação: |
1958 |
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Fonte/Imprenta: |
Journal of Animal Science, v. 17, n. 2, p. 304-312, May, 1958. |
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DOI: |
10.2527/jas1958.172304x |
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Idioma: |
Inglês |
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Conteúdo: |
The concentration of volatile fatty acids increased from approximately 110 to 150 uM per ml. of rumen fluid when the animals were changed from a hay-silage diet to a bloat-producing diet. The ratio of short chain rumen volatile fatty acids changed with each diet fed and with time in the case of the bloat-producing diet. Acetic acid decreased from 55 to 46 molar percent and propionic acid increased from 21 to 29 molar percent of the total volatile fatty acids in the rumen at 4 and 39 days, respectively, on the bloat-producing diet (average of 4 animals). The trend then reversed and acetic acid increased and propionic acid decreased to 60 and 20 molar percent, respectively, after the animals had been on the bloat-producing diet for 74 days. Reducing substances were never found in the rumen liquor, whereas lactic acid was nearly always found in the rumen samples taken 4.5 hours after feeding the bloat-producing diet. The dissimilation of glucose and cellobiose by rumen microorganisms removed from the rumen 4.5 hours after feeding showed that the proportion of the fatty acids produced changed with the diet. Following the changeover to the bloat-producing diet, the proportions of volatile fatty acids from the dissimilations were altered in an accentuated manner in the same direction as the rumen fluid. This indicates that as the individual fatty acid production in the rumen changes, the relative concentration in the rumen changes in the same direction and that relative concentration in the proportions of rumen volatile fatty acids may represent relatively large changes in their production. There were striking similarities in the volatile fatty acid proportions which resulted from the cell suspension dissimilations of glucose and cellobiose. The proportions of the fatty acids produced by in vitro dissimilations changed with each diet, and during the 74 days when the animals were fed the bloat-producing diet, were changing constantly. Valeric acid was apparently synthesized from carbohydrate in unusually large quantities by rumen bacteria. MenosThe concentration of volatile fatty acids increased from approximately 110 to 150 uM per ml. of rumen fluid when the animals were changed from a hay-silage diet to a bloat-producing diet. The ratio of short chain rumen volatile fatty acids changed with each diet fed and with time in the case of the bloat-producing diet. Acetic acid decreased from 55 to 46 molar percent and propionic acid increased from 21 to 29 molar percent of the total volatile fatty acids in the rumen at 4 and 39 days, respectively, on the bloat-producing diet (average of 4 animals). The trend then reversed and acetic acid increased and propionic acid decreased to 60 and 20 molar percent, respectively, after the animals had been on the bloat-producing diet for 74 days. Reducing substances were never found in the rumen liquor, whereas lactic acid was nearly always found in the rumen samples taken 4.5 hours after feeding the bloat-producing diet. The dissimilation of glucose and cellobiose by rumen microorganisms removed from the rumen 4.5 hours after feeding showed that the proportion of the fatty acids produced changed with the diet. Following the changeover to the bloat-producing diet, the proportions of volatile fatty acids from the dissimilations were altered in an accentuated manner in the same direction as the rumen fluid. This indicates that as the individual fatty acid production in the rumen changes, the relative concentration in the rumen changes in the same direction and that relative concentrat... Mostrar Tudo |
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Thesaurus Nal: |
Cellobiose; Fatty Acids; Feedlots; Rumen bacteria; Rumen microorganisms. |
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Categoria do assunto: |
L Ciência Animal e Produtos de Origem Animal |
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Marc: |
LEADER 02830naa a2200253 a 4500
001 2075837
005 2017-09-19
008 1958 bl uuuu u00u1 u #d
024 7 $a10.2527/jas1958.172304x$2DOI
100 1 $aJACOBSON, D. R.
245 $aFeedlot bloat studies. III. Rumen fatty acids and metabolic activity of rumen bacteria of animals placed on a bloat-producing diet.
260 $c1958
520 $aThe concentration of volatile fatty acids increased from approximately 110 to 150 uM per ml. of rumen fluid when the animals were changed from a hay-silage diet to a bloat-producing diet. The ratio of short chain rumen volatile fatty acids changed with each diet fed and with time in the case of the bloat-producing diet. Acetic acid decreased from 55 to 46 molar percent and propionic acid increased from 21 to 29 molar percent of the total volatile fatty acids in the rumen at 4 and 39 days, respectively, on the bloat-producing diet (average of 4 animals). The trend then reversed and acetic acid increased and propionic acid decreased to 60 and 20 molar percent, respectively, after the animals had been on the bloat-producing diet for 74 days. Reducing substances were never found in the rumen liquor, whereas lactic acid was nearly always found in the rumen samples taken 4.5 hours after feeding the bloat-producing diet. The dissimilation of glucose and cellobiose by rumen microorganisms removed from the rumen 4.5 hours after feeding showed that the proportion of the fatty acids produced changed with the diet. Following the changeover to the bloat-producing diet, the proportions of volatile fatty acids from the dissimilations were altered in an accentuated manner in the same direction as the rumen fluid. This indicates that as the individual fatty acid production in the rumen changes, the relative concentration in the rumen changes in the same direction and that relative concentration in the proportions of rumen volatile fatty acids may represent relatively large changes in their production. There were striking similarities in the volatile fatty acid proportions which resulted from the cell suspension dissimilations of glucose and cellobiose. The proportions of the fatty acids produced by in vitro dissimilations changed with each diet, and during the 74 days when the animals were fed the bloat-producing diet, were changing constantly. Valeric acid was apparently synthesized from carbohydrate in unusually large quantities by rumen bacteria.
650 $aCellobiose
650 $aFatty Acids
650 $aFeedlots
650 $aRumen bacteria
650 $aRumen microorganisms
700 1 $aLINDAHL, I. L.
700 1 $aMCNEILL, J. J.
700 1 $aSHAW, J. C.
700 1 $aDOETSCH, R. N.
700 1 $aDAVIS, R. E.
773 $tJournal of Animal Science$gv. 17, n. 2, p. 304-312, May, 1958.
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Registro original: |
Embrapa Caprinos e Ovinos (CNPC) |
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Registro Completo
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Biblioteca(s): |
Embrapa Meio Ambiente. |
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Data corrente: |
10/01/2017 |
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Data da última atualização: |
02/03/2017 |
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Tipo da produção científica: |
Artigo em Periódico Indexado |
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Circulação/Nível: |
A - 1 |
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Autoria: |
EBERHARDT, I. D. R.; SCHULTZ, B.; RIZZI, R.; SANCHES, I. D.; FORMAGGIO, A. R.; ATZBERGER, C.; MELLO, M. P.; IMMITZER, M.; TRABAQUINI, K.; LUIZ, A. J. B.; FOSCHIERA, W. |
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Afiliação: |
ISAQUE DANIEL ROCHA EBERHARDT, UnB; BRUNO SCHULTZ, INPE; RODRIGO RIZZI, UFPel; IEDA DELÁRCO SANCHES, INPE; ANTONIO ROBERTO FORMAGGIO, INPE; CLEMENT ATZBERGER, University of Natural Resources and Life Sciences, Vienna; MARCIO PUPIN MELLO, The Boing Company; MARKUS IMMITZER, University of Natural Resources and Life Sciences, Vienna; KLEBER TRABAQUINI, Epagri; ALFREDO JOSE BARRETO LUIZ, CNPMA; WILLIAM FOSCHIERA, INPE. |
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Título: |
Cloud cover assessment for operational crop monitoring systems in tropical areas. |
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Ano de publicação: |
2016 |
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Fonte/Imprenta: |
Remote Sensing, v. 8, n. 3, p. 1-14, 2016. |
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Idioma: |
Inglês |
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Conteúdo: |
Abstract: The potential of optical remote sensing data to identify, map and monitor croplands is well recognized. However, clouds strongly limit the usefulness of optical imagery for these applications. This paper aims at assessing cloud cover conditions over four states in the tropical and sub-tropical Center-South region of Brazil to guide the development of an appropriate agricultural monitoring system based on Landsat-like imagery. Cloudiness was assessed during overlapping four months periods to match the typical length of crop cycles in the study area. The percentage of clear sky occurrence was computed from the 1 km resolution MODIS Cloud Mask product (MOD35) considering 14 years of data between July 2000 and June 2014. Results showed high seasonality of cloud occurrence within the crop year with strong variations across the study area. The maximum seasonality was observed for the two states in the northern part of the study area (i.e., the ones closer to the Equator line), which also presented the lowest averaged values (15%) of clear sky occurrence during the main (summer) cropping period (November to February). In these locations, optical data faces severe constraints for mapping summer crops. On the other hand, relatively favorable conditions were found in the southern part of the study region. In the South, clear sky values of around 45% were found and no signi?cant clear sky seasonality was observed. Results underpin the challenges to implement an operational crop monitoring system based solely on optical remote sensing imagery in tropical and sub-tropical regions, in particular if short-cycle crops have to be monitored during the cloudy summer months. To cope with cloudiness issues, we recommend the use of new systems with higher repetition rates such as Sentinel-2. For local studies, Unmanned Aircraft Vehicles(UAVs) might be used to augment the observing capability. Multi-sensor approaches combining optical and microwave data can be another option. In cases where wall-to-wall maps are not mandatory, statistical sampling approaches might also be a suitable alternative for obtaining useful crop area information. MenosAbstract: The potential of optical remote sensing data to identify, map and monitor croplands is well recognized. However, clouds strongly limit the usefulness of optical imagery for these applications. This paper aims at assessing cloud cover conditions over four states in the tropical and sub-tropical Center-South region of Brazil to guide the development of an appropriate agricultural monitoring system based on Landsat-like imagery. Cloudiness was assessed during overlapping four months periods to match the typical length of crop cycles in the study area. The percentage of clear sky occurrence was computed from the 1 km resolution MODIS Cloud Mask product (MOD35) considering 14 years of data between July 2000 and June 2014. Results showed high seasonality of cloud occurrence within the crop year with strong variations across the study area. The maximum seasonality was observed for the two states in the northern part of the study area (i.e., the ones closer to the Equator line), which also presented the lowest averaged values (15%) of clear sky occurrence during the main (summer) cropping period (November to February). In these locations, optical data faces severe constraints for mapping summer crops. On the other hand, relatively favorable conditions were found in the southern part of the study region. In the South, clear sky values of around 45% were found and no signi?cant clear sky seasonality was observed. Results underpin the challenges to implement an operational cr... Mostrar Tudo |
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Palavras-Chave: |
Agriculture monitoring; Clear sky coverage; Cloudiness; Crop classification; Imagem de satélite; MODIS; Monitoramento agrícola. |
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Thesagro: |
Agricultura; Nuvem; Sensoriamento remoto. |
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Thesaurus NAL: |
Remote sensing. |
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Categoria do assunto: |
X Pesquisa, Tecnologia e Engenharia |
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URL: |
https://ainfo.cnptia.embrapa.br/digital/bitstream/item/153098/1/2016AP07.pdf
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Marc: |
LEADER 03189naa a2200373 a 4500
001 2060359
005 2017-03-02
008 2016 bl uuuu u00u1 u #d
100 1 $aEBERHARDT, I. D. R.
245 $aCloud cover assessment for operational crop monitoring systems in tropical areas.$h[electronic resource]
260 $c2016
520 $aAbstract: The potential of optical remote sensing data to identify, map and monitor croplands is well recognized. However, clouds strongly limit the usefulness of optical imagery for these applications. This paper aims at assessing cloud cover conditions over four states in the tropical and sub-tropical Center-South region of Brazil to guide the development of an appropriate agricultural monitoring system based on Landsat-like imagery. Cloudiness was assessed during overlapping four months periods to match the typical length of crop cycles in the study area. The percentage of clear sky occurrence was computed from the 1 km resolution MODIS Cloud Mask product (MOD35) considering 14 years of data between July 2000 and June 2014. Results showed high seasonality of cloud occurrence within the crop year with strong variations across the study area. The maximum seasonality was observed for the two states in the northern part of the study area (i.e., the ones closer to the Equator line), which also presented the lowest averaged values (15%) of clear sky occurrence during the main (summer) cropping period (November to February). In these locations, optical data faces severe constraints for mapping summer crops. On the other hand, relatively favorable conditions were found in the southern part of the study region. In the South, clear sky values of around 45% were found and no signi?cant clear sky seasonality was observed. Results underpin the challenges to implement an operational crop monitoring system based solely on optical remote sensing imagery in tropical and sub-tropical regions, in particular if short-cycle crops have to be monitored during the cloudy summer months. To cope with cloudiness issues, we recommend the use of new systems with higher repetition rates such as Sentinel-2. For local studies, Unmanned Aircraft Vehicles(UAVs) might be used to augment the observing capability. Multi-sensor approaches combining optical and microwave data can be another option. In cases where wall-to-wall maps are not mandatory, statistical sampling approaches might also be a suitable alternative for obtaining useful crop area information.
650 $aRemote sensing
650 $aAgricultura
650 $aNuvem
650 $aSensoriamento remoto
653 $aAgriculture monitoring
653 $aClear sky coverage
653 $aCloudiness
653 $aCrop classification
653 $aImagem de satélite
653 $aMODIS
653 $aMonitoramento agrícola
700 1 $aSCHULTZ, B.
700 1 $aRIZZI, R.
700 1 $aSANCHES, I. D.
700 1 $aFORMAGGIO, A. R.
700 1 $aATZBERGER, C.
700 1 $aMELLO, M. P.
700 1 $aIMMITZER, M.
700 1 $aTRABAQUINI, K.
700 1 $aLUIZ, A. J. B.
700 1 $aFOSCHIERA, W.
773 $tRemote Sensing$gv. 8, n. 3, p. 1-14, 2016.
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Embrapa Meio Ambiente (CNPMA) |
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