|
Registro Completo |
|
Biblioteca(s): |
Embrapa Meio-Norte. |
|
Data corrente: |
14/10/1997 |
|
Data da última atualização: |
14/10/1997 |
|
Autoria: |
VULICH, S. A.; HANRAHAN, J. P.; O'RIORDAN, E. G. |
|
Título: |
Pasture sampling for the estimation of herbage intake using n-alkanes: evaluation of alternative sampling procedures. |
|
Ano de publicação: |
1993 |
|
Fonte/Imprenta: |
Irish Journal of Agricultural and Food Research. v. 32, n. 1, p. 1-11. |
|
Idioma: |
Inglês |
|
Conteúdo: |
Two experiments were conducted to i) assess the magnitude of sampling variation in estimates of n-alkane concentrations in herbage harvested by individual oesophageal fistulated wethers, and ii) compare animal-based (fistulated animals) and other pasture sampling procedures (clipping and hand-plucking) for the determination of herbage n-alkane concentrations. In the first experiment extrusa samples from oesophageal fistulated wethers, collected on 3 days per week for three l-week periods between mid-May and mid-July, were used to evaluate among-animal variation in herbage n-alkane concentrations. The second experiment, conducted in the autumn, compared n-alkane concentrations determined form oesophageal extrusa (pooled mateiral from four wethers), hand plucked and mechanically clipped herbage samples collected on 7 days over a 15-day period. Herbage n-alkane concentrations varied significantly (P<0.05) among weeks and among days within weeks, and among days, indicating the need for pasture sampling throughtou the experimental period. No significant differences were detected in the n-alkane concentrations among samples obtained by clipping, hand plucking and those based on pooled extrusa. There was also no difference in variability between the animal based and the non-animal based samples. The combined results from both experiments indicated that daily herbage samples, based on three or four extrusa samples or one non-animal based sample, yielded CVs of the order of 0.08, 0.14 and 0.09 for the concentrations of n-hentriacontane (C31), n-dotriacontane (C32) and n-tritriacontane (C33), respectively. Sampling variation in estimates of herbage crude protein concentration and in vitro dry matter digestibility were of similar magnitude to that for C31 and C33. MenosTwo experiments were conducted to i) assess the magnitude of sampling variation in estimates of n-alkane concentrations in herbage harvested by individual oesophageal fistulated wethers, and ii) compare animal-based (fistulated animals) and other pasture sampling procedures (clipping and hand-plucking) for the determination of herbage n-alkane concentrations. In the first experiment extrusa samples from oesophageal fistulated wethers, collected on 3 days per week for three l-week periods between mid-May and mid-July, were used to evaluate among-animal variation in herbage n-alkane concentrations. The second experiment, conducted in the autumn, compared n-alkane concentrations determined form oesophageal extrusa (pooled mateiral from four wethers), hand plucked and mechanically clipped herbage samples collected on 7 days over a 15-day period. Herbage n-alkane concentrations varied significantly (P<0.05) among weeks and among days within weeks, and among days, indicating the need for pasture sampling throughtou the experimental period. No significant differences were detected in the n-alkane concentrations among samples obtained by clipping, hand plucking and those based on pooled extrusa. There was also no difference in variability between the animal based and the non-animal based samples. The combined results from both experiments indicated that daily herbage samples, based on three or four extrusa samples or one non-animal based sample, yielded CVs of the order of 0.08, 0.1... Mostrar Tudo |
|
Palavras-Chave: |
Avalia?ao; Intake; N-alkanes; Pasture; Variation. |
|
Thesagro: |
Amostragem; Consumo; Forragem. |
|
Thesaurus Nal: |
sampling. |
|
Categoria do assunto: |
-- |
|
Marc: |
LEADER 02488naa a2200253 a 4500
001 1054793
005 1997-10-14
008 1993 bl --- 0-- u #d
100 1 $aVULICH, S. A.
245 $aPasture sampling for the estimation of herbage intake using n-alkanes$bevaluation of alternative sampling procedures.
260 $c1993
520 $aTwo experiments were conducted to i) assess the magnitude of sampling variation in estimates of n-alkane concentrations in herbage harvested by individual oesophageal fistulated wethers, and ii) compare animal-based (fistulated animals) and other pasture sampling procedures (clipping and hand-plucking) for the determination of herbage n-alkane concentrations. In the first experiment extrusa samples from oesophageal fistulated wethers, collected on 3 days per week for three l-week periods between mid-May and mid-July, were used to evaluate among-animal variation in herbage n-alkane concentrations. The second experiment, conducted in the autumn, compared n-alkane concentrations determined form oesophageal extrusa (pooled mateiral from four wethers), hand plucked and mechanically clipped herbage samples collected on 7 days over a 15-day period. Herbage n-alkane concentrations varied significantly (P<0.05) among weeks and among days within weeks, and among days, indicating the need for pasture sampling throughtou the experimental period. No significant differences were detected in the n-alkane concentrations among samples obtained by clipping, hand plucking and those based on pooled extrusa. There was also no difference in variability between the animal based and the non-animal based samples. The combined results from both experiments indicated that daily herbage samples, based on three or four extrusa samples or one non-animal based sample, yielded CVs of the order of 0.08, 0.14 and 0.09 for the concentrations of n-hentriacontane (C31), n-dotriacontane (C32) and n-tritriacontane (C33), respectively. Sampling variation in estimates of herbage crude protein concentration and in vitro dry matter digestibility were of similar magnitude to that for C31 and C33.
650 $asampling
650 $aAmostragem
650 $aConsumo
650 $aForragem
653 $aAvalia?ao
653 $aIntake
653 $aN-alkanes
653 $aPasture
653 $aVariation
700 1 $aHANRAHAN, J. P.
700 1 $aO'RIORDAN, E. G.
773 $tIrish Journal of Agricultural and Food Research.$gv. 32, n. 1, p. 1-11.
Download
Esconder MarcMostrar Marc Completo |
|
Registro original: |
Embrapa Meio-Norte (CPAMN) |
|
