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Drought and irrigation water demand: food for thought | Secheresse et demande en eau d'irrigation: elements de reflexion
1998
Morardet, S. (Cemagref Institut de Recherche pour l'Ingenierie de l'Agriculture et de l'Environnement, Montpellier (France)) | Mailhol, J.C. | Vidal, A. | Garin, P. | Gleyses, G.
Cet article fait le point sur l'etat actuel des connaissances en matiere de consommations d'eau pour l'irrigation en France, tres variables dans le temps et l'espace. Au cours des dix dernieres annees, les superficies irriguees ont augmente de facon importante mais variable selon les regions, malgre la reforme de la PAC. Avec 43 % de la surface irriguee, le mais reste la principale culture irriguee. La connaissance des superficies irriguees, satisfaisante sur le plan statistique, est insuffisante pour une estimation quantitative des prelevements d'eau pour l'irrigation, du fait de la variabilite importante des besoins en eau des cultures et de la meconnaissance des pratiques d'apports d'eau des irriguants. Le Cemagref [Institut de recherche pour l'ingenierie de l'agriculture et de l'environnement] a developpe une methode d'estimation a l'echelle regionale des apports d'eau d'irrigation lors d'une secheresse severe. Les besoins en eau theoriques du mais, choisi comme culture de reference, sont evalues pour les principales regions de production, a partir des donnees climatiques et des caracteristiques des sols et en tenant compte des pratiques de restriction des apports d'eau des irriguants lors d'une secheresse prolongee. Sur la base de ce travail, il est possible de proposer un dispositif de suivi et d'analyse previsionnelle de la demande en eau des agriculteurs a l'echelle regionale, de facon a mieux apprecier les risques de tensions sur la ressource, et a mettre en place des modes de gestion plus efficaces. Ce dispositif devra s'appuyer entre autres sur une meilleure connaissance des pratiques des irriguants
显示更多 [+] 显示较少 [-]Micro-organisms used as indicators of fecal contamination of water and food | Les micro-organismes indicateurs de contamination fecale de l'eau et des aliments
1998
Bornert, G. (Commissariat de l'Armee de Terre, Saint Cloud (France). Service Central d'Etudes et de Realisations)
Les iidicateurs de contamination fecale sont des micro-organismes dont la presence dans une eau ou un aliment est le signe d'ume contamination par des matieres fecales. En France, quatre flores bacteriennes sont habituellement recherchees au laboratoire: les coliformes, les coliformes thermotolerants, les Escherichia coli et les enterocoques. Leur denombrement, effectue selon des methodes normalisees simples et sensibles, se substitue a la recherche des micro-organismes pathogenes, souvent fastidieuse. Les connaissances acquises recemment dans le domaine de l'ecologie des coliformes et des enterocoques conduisent cependant a interpreter avec prudence les resultats d'analyses: l'origine fecale des indicateurs usuels n'est pas toujours certaine. Pour assurer plus efficacement la protection de la Sante Publique, il est imperatif de disposer d'indicateurs plus fiables. Les recherches actuelles s'orientent vers les bacteriophages a ARN F-specifiques et vers les bacteries du genre Bifidobacterium
显示更多 [+] 显示较少 [-]Ecophysiological characterization of common food-borne fungi in relation to pH and water activity under various atmospheric compositions 全文
1998
Haasum, I. | Nielsen, P.V.
The combined effects of pH, water activity (a(w)), oxygen (O2) and carbon dioxide (CO2) levels on growth and sporulation of 10 common food-borne fungi were studied. The use of a multivariate statistical method (PLS) for the analysis of data showed that the fungi could be grouped according to their physiological response to changes in the four tested factors. Carbon dioxide, a(w) and pH were found to be the most significant factors describing differences and similarities among the fungi. Maximal inhibitory effect of elevated levels of CO2 (5-25%) and decreased a(w) (0.99-0.95) varied among the 10 species from 6 to 77% and from 52 to 100%, respectively. Sporulation of the fungi was sensitive to all tested factors. Furthermore, interaction of CO2 and a(w) displayed a significant effect on sporulation. It was shown that different fungal species associated with the same ecosystem responded similarly to changes in the tested factors. Thus, fungi which are not phylogenetically related may be physiologically related or show a common strategy of life.
显示更多 [+] 显示较少 [-]Ecophysiological characterization of common food-borne fungi in relation to pH and water activity under various atmospheric compositions
1998
Haasum, I. | Nielsen, P.V. (Department of Biotechnology, Technical University of Denmark, 2800 Lyngby (Denmark))
Effects of food and water withdrawal and high temperature exposure on diurnal variation in blood viscosity of broiler chickens 全文
1998
Zhou, W.T. | Fujita, M. | Yamamoto, S.
1. Three experiments were conducted to investigate the diurnal variation of blood viscosity in broilers. In experiment 1 food and water were supplied freely at 20 degrees C (20-FW). In experiment 2 food and water were withdrawn at 20 degrees C (20-NFW), while in experiment 3 food and water withdrawn at 30 degrees C (30-NFW). 2. Blood sampling time points were 09.00 h, 15.00 h, 21.00 h, 03.00 h and 09.00 h the next day in each experiment. 3. In all experiments, whole blood viscosity (WBV), red blood cell count (RBC) and haematocrit (HCT) were greater during the dark (21.00 h and 03.00 h) than during the light period. During the dark period, there were no differences in WBV, RBC and HCT between 20-FW and 20-NFW, or between 20-NFW and 30-NFW. At 09.00 h, WBV and HCT were higher in 20-FW than in 20-NFW. At 15.00 h and 09.00 h (day 2), WBV and HCT were greater in 20-NFW than in 30-NFW. 4. There were no light-dark differences in plasma viscosity (PV), plasma protein concentration (PPC) or mean corpuscular volume (MCV) in any experiment. However, 20-NFW birds had a lower PPC and higher MCV compared with 20-FW, and a higher PPC and lower MCV compared with 30-NFW, while no difference was found in PV. 5. WBV increased linearly with RBC and HCT. PV increased with PPC, while MCV decreased. 6. These results indicate that there is diurnal variation in whole blood viscosity, which is greater during the dark than during the light period. During the light period it is strongly influenced by high environmental temperature and food and water withdrawal.
显示更多 [+] 显示较少 [-]Effects of food and water withdrawal and high temperature exposure on diurnal variation in blood viscosity of broiler chickens
1998
Zhou, W.T. | Fujita, M. | Yamamoto, S. (Faculty of Applied Biological Science, Hiroshima University, Higashi-Hiroshima, 739-0046 (Japan))
Manual de laboratórios: solo, água, nutrição vegetal, nutrição animal e alimentos. 1. Coleta, acondicionamento e preparo de amostras. 全文
2023 | 1998
NOGUEIRA, A. R. DE A. | MACHADO, P. L. O. DE A. | CARMO, C. A. F. DE S. DO | FERREIRA, J. R. | ANA RITA DE ARAUJO NOGUEIRA, CPPSE; PEDRO LUIZ OLIVEIRA DE A MACHADO, CNPS; CIRIACA ARCANGELA F DE S DO CARMO, CNPS; JOSE ROBERTO FERREIRA, CNPGL.
Coleta, acondicionamento e preparo de amostras: Solos: amostragem; criterios para a divisao da area de amostragem; numero de amostras simples ou subamostras; composicao da amostra; material para a amostragem; epoca de amostragem; frequencia de amostragem; algumas recomendacoes gerais para a amostragem; acondicionamento e identificacao da amostra; registro e preparo da amostra: registro; secagem; moagem, peneiragem e armazenagem; Agua: quando, onde e como amostrar; acondicionamento de amostras: tipo e procedimentos de limpeza; preservacao de amostras; Tecidos vegetais: amostragem; procedimentos para coletar amostras de folhas no campo: coleta de amostra; moagem; armazenagem; integridade da amostra; problemas de contaminacao; arquivo de amostras; Tecidos e produtos animais: aspectos importantes relacionados a coleta de amostras; objetivo da preparacao das amostras; preparacao das amostras: recebimento; identificacao e registro; pre-acondicionamento: amostras de origem vegetal; amostra de fezes; pre-secagem; Moagem; acondicionamento: fluxogramas e figuras das etapas de preparacao de amostras; Preparo de amostras de ingredientes e suplementos mineiras; Outros tipos de amostras de origem animal: osso; figado: biopsia; necropsia; observacoes; Sangue: plasma; soro; desproteinizacao; liquidos de rumen; liquidos de abomaso e de ileo; urina; extrusa, leite; pelo; Alimentos para consumo humano: Fundamento; Equipamentos; Procedimentos: inspecao e identificacao da amostra; solubilizacao da amostra; preparo da amostra; conservacao da amostra.
显示更多 [+] 显示较少 [-]Manual de laboratórios: solo, água, nutrição vegetal, nutrição animal e alimentos. 1. Coleta, acondicionamento e preparo de amostras. 全文
2023 | 1998
NOGUEIRA, A. R. de A. | MACHADO, P. L. O. de A. | CARMO, C. A. F. de S. do | FERREIRA, J. R. | ANA RITA DE ARAUJO NOGUEIRA, CPPSE; PEDRO LUIZ OLIVEIRA DE A MACHADO, CNPS; CIRIACA ARCANGELA F DE S DO CARMO, CNPS; JOSE ROBERTO FERREIRA, CNPGL.
Coleta, acondicionamento e preparo de amostras: Solos: amostragem; criterios para a divisao da area de amostragem; numero de amostras simples ou subamostras; composicao da amostra; material para a amostragem; epoca de amostragem; frequencia de amostragem; algumas recomendacoes gerais para a amostragem; acondicionamento e identificacao da amostra; registro e preparo da amostra: registro; secagem; moagem, peneiragem e armazenagem; Agua: quando, onde e como amostrar; acondicionamento de amostras: tipo e procedimentos de limpeza; preservacao de amostras; Tecidos vegetais: amostragem; procedimentos para coletar amostras de folhas no campo: coleta de amostra; moagem; armazenagem; integridade da amostra; problemas de contaminacao; arquivo de amostras; Tecidos e produtos animais: aspectos importantes relacionados a coleta de amostras; objetivo da preparacao das amostras; preparacao das amostras: recebimento; identificacao e registro; pre-acondicionamento: amostras de origem vegetal; amostra de fezes; pre-secagem; Moagem; acondicionamento: fluxogramas e figuras das etapas de preparacao de amostras; Preparo de amostras de ingredientes e suplementos mineiras; Outros tipos de amostras de origem animal: osso; figado: biopsia; necropsia; observacoes; Sangue: plasma; soro; desproteinizacao; liquidos de rumen; liquidos de abomaso e de ileo; urina; extrusa, leite; pelo; Alimentos para consumo humano: Fundamento; Equipamentos; Procedimentos: inspecao e identificacao da amostra; solubilizacao da amostra; preparo da amostra; conservacao da amostra.
显示更多 [+] 显示较少 [-]Determination of the Aeromonas group in deep frozen food , contaminated environmental water and relationship in humans | Identification d'Aeromonas dans les aliments surgelés contaminés par l'eau. Conséquences pour l'homme
1998
Matouq, A.A. ((Eoetvoes Lorand University, Budapest (Hungary). Department of Microbiology))
Aeromonas, like other human enteropathogens, are capable of producing infections at sites outside the gastrointestinal tract and skin, via food or water . The presence of Aeromonas in foodstuffs and in particular the possibility of its growth under refrigerated conditions leads to the conclusion that refrigerated may present potential sources of food borne infection. 24 strains used in our study were from different sources, water, faeces, blood, sweat, row milk, and poultry sausages samples.The most frequent strain A. hydrophila, was found and also A. salmonicida, A. caviae and A. sobria . Refrigerated food may be contaminated with both psychrotrophic and mesophilic pathogens.
显示更多 [+] 显示较少 [-]Daily ration estimates and comparative study of food consumption in nine species of deep-water decapod crustaceans of the NW Mediterranean 全文
1998
Maynou, Francesc | Cartes, Joan Enric
11 pages, 3 figures, 3 tables | Estimates of the daily ration consumed by 9 species of decapod crustaceans were obtained from 2 deep-water samplings over the middle and lower continental slope of the NW Mediterranean. The daily rations obtained varied by an order of magnitude from the slow-moving, crab-like species (< 0.1 g dry food per 100 g predator body weight) to the actively swimming mesopelagic shrimps (> 1.0 g dry food per 100 g predator body weight). A multivariate analysis allowed us to relate the variability in daily ration estimates to the functional morphology and ecology of the species considered. The functional morphology and ecology of the species studied are defined in terms of body shape, swimming capability, trophic diversity and spatial distribution. We found that body shape (ratio of carapace length to carapace width) and trophic diversity (H') account for most of the variability in the amount of food consumed by decapods. The food consumption pattern established for our decapod crustaceans is compared to a similar pattern reported for deep-water fishes | Peer Reviewed
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