|
|
|
| Registros recuperados: 65 | |
|
|
| Samain, Jean-francois; Boucher, Jean. |
| A method for nutrition, production and ecological studies by calculation of amylase specific activity of zooplankton is described. The method's adjustment is based on the biochemical properties of the enzyme. The activity measurement of a single Artemia salina, a few Copepods, or of the whole contents of a net is possible with 5 % accuracy. Up to 15 samples can be analysed within one hour with good reproducible results. The method is well suited to in situ studies aboard oceanographic vessels. [NOT CONTROLLED OCR] |
| Tipo: Text |
Palavras-chave: Histoire Ifremer. |
| Ano: 1974 |
URL: http://archimer.ifremer.fr/doc/1974/publication-5424.pdf |
| |
|
|
| Boucher, Jean; Samain, Jean-francois. |
| Specific amylase activity was measured during the CINECA III cruise in the moroccan upwelling area. In this region the population is homogeneous and in a steady state during the study. The hypothesis of enzymatic activity rate as a nutrition index is enlarged by a relation with diet, fast and feeding stock. A mathematical expression is given of the relationship between zooplankton digestive activity and phytoplankton biomass. Analysis of this equation shows a daily physiological rhythm of the amylase activity. [NOT CONTROLLED OCR] |
| Tipo: Text |
Palavras-chave: Histoire Ifremer. |
| Ano: 1974 |
URL: http://archimer.ifremer.fr/doc/1974/publication-5149.pdf |
| |
|
|
| Samain, Jean-francois; Boucher, Jean; Buestel, Dominique; Borne, M.; Le Coz, Jean-rene. |
| The relations between the activity of the digestive enzymes amylase and proteases were studied on Artemia salina L. For this purpose, a method for measuring the ingestion was developed compatible with the speed of response of the digestive enzymes. It is demonstrated that the proteic density variations in Artemia of the same size are in relation to the food content of their digestive tract. Therefore the measurement of the size and weight of proteins (proteic density) allows the evaluation of the ingestion. With the aid of this method, a daily ingestion rhythm, with bimodal character, could be demonstrated. The influence on the ingestion, of the concentration of food available (Tetraselmis suecica Butcher) was studied in function of the size of the... |
| Tipo: Text |
Palavras-chave: Histoire Ifremer. |
| Ano: 1975 |
URL: http://archimer.ifremer.fr/doc/1975/publication-5104.pdf |
| |
|
|
| Boucher, Jean; Laurec, Alain; Samain, Jean-francois; Smith, S. L.. |
| The amylase and trypsin activity of the most important zooplankton species has been measured in the upwelling zone of the Spanish Sahara during the "Gibraltar ecophysiological cruise" of the oceanographic vessel Jean Charcot. The analysis of the results was carried out for the double purpose of demonstrating the regulation by the nutrition of the activities of digestive enzymes and utilizing these results to study the feeding behavior under the natural environmental conditions of an ecosystem. With regard to its biological significance, the influence of the quality and quantity of food available has been demonstrated by a bouble experimental approach followed by a statistical one. Significant correlations were found between the specific amylase activity... |
| Tipo: Text |
Palavras-chave: Histoire Ifremer. |
| Ano: 1975 |
URL: http://archimer.ifremer.fr/doc/1975/publication-5105.pdf |
| |
|
|
| Boucher, Jean; Samain, Jean-francois. |
| The feeding of the zooplankton has been studied in the natural environment of an upwelling ecosystem by measurements of amylase and protease activities. The hypothesis of enzymatic specific activity as a nutritional index is extended by a correlation with Lorenzen's grazing index. There is no correlation between amylase and protease activity so the diet of the populations is described by the ratio of these two enzymatic activities. Variations of relative feeding rate for Calanus, Temora, Acartia, Podon, and for the total sample are discussed in relation to the ecological and trophic characteristics of the environment. |
| Tipo: Text |
Palavras-chave: Histoire Ifremer. |
| Ano: 1975 |
URL: http://archimer.ifremer.fr/doc/1975/publication-5463.pdf |
| |
|
| |
|
| |
|
|
| Samain, Jean-francois; Moal, Jeanne; Alayse-danet, Anne-marie; Daniel, Jean-yves; Le Coz, Jean-rene. |
| Model for Rapid Detection of Sublethal Effects of Pollutants. II. An in situ Example: Anomalous Metabolism of the Hyponeustonic Copepod Anomalocera patersoni Coinciding with an Oil Spill An unusual correlation has been obsemed between the amylase and trypsin content of a natural zooplankton population and of the hyponeustonic copepod Anomalocera patersoni and the oil spill of the "Amoco Cadiz" in 1978. This anomaly has also been obsewed in Artemia sp. cultures (San Francisco Bay strain) poisoned by copper. This phenomenon could originate from a general physiological perturbation. Such a non-specific perturbation could explain the anormal correlation between parameters which are usually independent and specifically regulated. The determination of such... |
| Tipo: Text |
Palavras-chave: Histoire Ifremer. |
| Ano: 1981 |
URL: http://archimer.ifremer.fr/doc/1981/publication-5362.pdf |
| |
|
|
| Samain, Jean-francois; Moal, Jeanne; Daniel, Jean-yves; Le Coz, Jean-rene. |
| The ingestion rate and the resulting assimilation calculated by means of a law taking into account activities of the digestive enzymes (amylase and trypsin) on the carbohydrates and proteins ingested, are determined in two experiments on Artemia. They are fed the same species of phytoplankton (Tetraselmis suecica), at the same concentration but with two chemical compositions. In one experiment, the cells are rich in carbohydrates and poor in proteins, and in the second one they are poor in carbohydrates, rich in proteins. Different observed ingestion rates induce a balance in proteins, and a large difference in the carbohydrates ingested. When digestive enzymes are taken into account, the assimilated carbohydrates and proteins are similar (explaining the... |
| Tipo: Text |
Palavras-chave: Histoire Ifremer. |
| Ano: 1981 |
URL: http://archimer.ifremer.fr/doc/1981/publication-5360.pdf |
| |
|
|
| Samain, Jean-francois; Moal, Jeanne. |
| The regulation of the synthesis of the digestive enzymes of the zooplankton and the brine shrimp (amylase and trypsine activity) has been studied to find some nutrition indexes enabling the description of the zooplankton's nutritive activity in situ. These regulations lead us to tackle three domains of pelagic ecology:- The evaluation of the organisms' nutrive needs and the capacity of the environment to satisfy them.- The monitoring of the pelagic ecosystem- The disturbance of the ecosystems. |
| Tipo: Text |
Palavras-chave: Histoire Ifremer. |
| Ano: 1981 |
URL: http://archimer.ifremer.fr/doc/1981/publication-5972.pdf |
| |
|
| |
|
|
| Samain, Jean-francois; Cochard, Jean-claude; Chevolot, Lionel; Daniel, Jean-yves; Jeanthon, C.; Le Coz, Jean-rene; Marty, Y.; Moal, Jeanne; Prieur, D.; Salaun, Michele. |
| Some positive growth differences can be observed, all year long, in Pecten maximus larvae cultivated in an old fishpond, compared with the water which flows into it periodically. These waters are filtered at 1 µm through CUNO cartridges. Moreover, the larvae are cultivated in the same light, temperature and food (cultured phytoplankton) conditions. This difference is significant in terms of larvae size, dry weight, organic matter, ashes, total proteins, glycogen, and lipids. A series of preliminary observations on the chemical composition of these two waters after filtration (amino acids, fatty acids, organic mater, nutritive salts), on the bacterial flora (total, heterotrophic organisms, vibrio), on the particular material using electron microscopy, on... |
| Tipo: Text |
Palavras-chave: Larve; Ecloserie; Pecten maximus; Facteur croissance; Qualité eau. |
| Ano: 1986 |
URL: http://archimer.ifremer.fr/doc/1986/acte-6185.PDF |
| |
|
|
| Poulet, Sa; Harris, Rp; Martin-jezequel, Veronique; Moal, Jeanne; Samain, Jean-francois. |
| By measuring water soluble extracts of free amino acids (DF AA) in the diets and faecal pellets of copepods using high performance liquid chromatography (HPLC), it was found that the molar composition of these molecules in the faeces produced depends on the type of food selected and reflects the hydrolysis of food proteins during digestion. On average, four amino acids (ASP, SER, GLY and LEU) together accounted for 63% of total DF AA in the faecal pellets of a variety of copepod species. The diversity of DFAA in copepod faecal pellets was higher than in sea water or in particles and phytoplankton cells ingested by copepods. These first results on DFAA in copepod faecal material indicate the importance of zooplankton faeces in the flux of dissolved nitrogen... |
| Tipo: Text |
Palavras-chave: Acides aminés; Copépodes; Fécès; Ammo acids; Copepods; Faeces. |
| Ano: 1986 |
URL: http://archimer.ifremer.fr/doc/00111/22269/19944.pdf |
| |
|
| |
|
| |
|
| |
|
|
| Moal, Jeanne; Samain, Jean-francois; Le Coz, Jean-rene; Daniel, Jean-yves. |
| Crassostrea gigas oysters cultivated in Marennes-Oleron Bay (France), face seasonal variations in the environment: salinity, turbidity, phytoplanktonic production, and the tidal rhythm of emersion. The oysters are maintained at different depths to reduce competition for space (e.g. by settlement of mussel spat). The physiological responses of two groups of oysters to different periods of emersion were studied using a seasonal sampling strategy: one group was on a flat part of the area, and the effect of emersion was studied in a short time survey (less than three hours emersion at low tide); the other was located in a very narrow place with a steep slope. This group was subdivided into three, according to bathymetric position, to study the long term effect... |
| Tipo: Text |
Palavras-chave: Crassostrea gigas; Physiology; Emersion; AEC; Digestive enzimes; Marennes-Oleron Bay. |
| Ano: 1989 |
URL: http://archimer.ifremer.fr/doc/00038/14885/12208.pdf |
| |
|
| |
|
|
| Jacq, E; Moal, Jeanne; Samain, Jean-francois; Corre, S; Daniel, J; Nicolas, Jean-louis; Cochard, Jean-claude; Fera, P. |
| Larval rearings were performed with seawater either freshly pumped or after storage in a pond. Concerning bacterial populations these waters were characterized by a high diversity, little sized bacteria whose few of them (1%) were cultivable on Zobell medium. In the tanks, the bacterial ecosystem was modified by the presence of antibiotics, larvae and algae: the diversity was lowered, the cellular volume was increased by a factor 2 to 5, 100% bacteria were cultivable and chloramphenicol resistant, and their metabolism changed. Taxonomic screening showed no differences among the two waters neither at the beginning nor at the end of the rearings. However, depending on the water (stored or not) differences were identified for bacterial physiology and... |
| Tipo: Text |
Palavras-chave: Marine aquaculture; Pond culture; Scallop culture; Ecology; Antibiotics; Organic matter; Grazing; Carbohydrates; Mathematical models; Modelling; Growth; Bacterial diseases; Biological production; Culture tanks; Larvae; Rearing. |
| Ano: 1992 |
URL: http://archimer.ifremer.fr/doc/1992/acte-914.pdf |
| |
|
|
| Gerard, Andre; Boudry, Pierre; Bougrier, Serge; Hawkins, A. J. S.; Thiriot Quievreux, Catherine; Wilkins, N. P.; Zouros, Eleftherios; Bonhomme, Francois; Buestel, Dominique; Samain, Jean-francois. |
| The UE project "GENEPHYS", initiated by the IFREMER laboratory GAP-La Tremblade (Génétique Aquaculture et Pathologie) and CREMA-L'Houmeau (Centre de Recherche en Ecologie marine et Aquaculture), aims to establish the relationships between physiological traits involved in growth (oxygen consumption, absorption efficiency, scope for growth) and their genetic bases (determinism, variability within and among populations) in cupped oyster Crassostrea gigas. The main objectives are : 1. To express the maximum variability of growth, both at the larval stage and at the adult stage, in a oyster population originating from parents of various origins. 2. To check the persistence over the time, of growth performance and related physiological functions. 3. To explain... |
| Tipo: Text |
Palavras-chave: Genetic; Determinism; Variability; Physilogy; Oxygen consumption; Absorption efficiency; Growth; Oysters; Crassostrea gigas. |
| Ano: 1997 |
URL: http://archimer.ifremer.fr/doc/00050/16150/13633.pdf |
| |
| Registros recuperados: 65 | |
|
|
|
