The Growth of Brown Trout (Salmo Trutta Linn.)

1946 ◽  
Vol 22 (3-4) ◽  
pp. 130-144
Author(s):  
MARGARET E. BROWN
Keyword(s):  
Growth Rate ◽  
Specific Growth Rate ◽  
Rapid Growth ◽  
Salmo Trutta ◽  
Specific Growth ◽  
Condition Factor ◽  
Specific Rate ◽  
Annual Growth Rate ◽  
Size Hierarchy ◽  
Rate Of Growth

1. Two-year-old trout were grown in environments where the following factors were controlled: temperature, amount and intensity of illumination, rate of flow, composition and aeration of the water, quality and quantity of food and amount of living space. 2. The specific growth rate of an individual depended on its size relative to that of the others in the group. It is suggested that subgroups of four or five individuals existed within the size hierarchy and were reorganized at intervals of about 3 months. 3. There was an optimum degree of crowding for rapid growth, and overcrowding led to lower appetite and efficiency of utilization of food, while under-crowded trout ate and grew erratically. 4. In spite of constant environmental conditions, all the fish had an annual growth-rate cycle, with an autumn check, a spring maximum, rapid summer growth and another autumn check, which coincided with maturation of the gonads when they became 3 years old. 5. Individual specific growth rates fluctuated over periods of 4-6 weeks, and rapid growth in length alternated with rapid growth in weight. The specific rate of growth in length was directly proportional to the condition factor. The amount of food eaten, the efficiency of utilization of food and the specific rate of growth in weight varied with the condition factor and were maximal for a factor of about 1·10. 6. The growth-rate fluctuations were exaggerated and the efficiency was greater when the food supply was restricted. At the maintenance level the change in weight was directly proportional to the amount of food eaten. The maintenance requirement decreased, relatively, with increase in body weight. 7. The mean specific growth rate was higher with less than 12 hr. per diem of the standard illumination.

The Growth of Brown trout (Salmo Trutta Linn.)

1946 ◽  
Vol 22 (3-4) ◽  
pp. 118-129
Author(s):  
MARGARET E. BROWN
Keyword(s):  
Growth Rate ◽  
Specific Growth Rate ◽  
Growth Rates ◽  
Salmo Trutta ◽  
Specific Growth ◽  
Specific Rate ◽  
Size Hierarchy ◽  
Living Space ◽  
Brown Trout Salmo Trutta ◽  
Specific Growth Rates

1. Groups of trout fry of the same parentage were grown in environments where the following factors were controlled: temperature, amount and intensity of illumination, rate of water flow, aeration and chemical composition of the water, amount of living space and quality of food supply. They were allowed to eat as much as they would, and individual weights were recorded during the first 8 months after the beginning of feeding. 2. There was soon an increase in the range of individual weight in each group of fry, and thereafter the larger fry grew faster than smaller ones. When the larger fry were removed, the smaller ones grew at an increased specific rate, and when larger fry were added, the smaller ones grew more slowly. It is suggested that a ‘size hierarchy’ was established within each group, and an individual's specific growth rate depended on its position in the order of decreasing weight. 3. There was an optimum degree of crowding for maximum productivity. Compared with the fry in this group, the specific growth rates of individuals in larger, more crowded groups depended on the number of fish of larger size, while in smaller, less crowded groups, individuals grew at rates depending on the proportion of fish which were larger and smaller. 4. Alevin weight had little effect on the specific growth rates of fry. 5. There were differences between the growth histories of fry derived from alevins of the same weight and descended from the same father but different mothers (all of the same stock, age and size). 6. The specific growth rates decreased as the fry grew older, but there was no correlation between body weight and specific growth rate, except for the size hierarchy effect within each group. This effect had a greater influence on the size of individual fry than had either alevin weight or heredity.

The effect of specific growth rate on protein synthesis and secretion in the filamentous fungus Trichoderma reesei

Microbiology ◽  
2005 ◽  
Vol 151 (1) ◽  
pp. 135-143 ◽  
Author(s):  
Tiina M. Pakula ◽  
Katri Salonen ◽  
Jaana Uusitalo ◽  
Merja Penttilä
Keyword(s):  
Growth Rate ◽  
Protein Synthesis ◽  
Specific Growth Rate ◽  
Trichoderma Reesei ◽  
Growth Rates ◽  
Protein Production ◽  
Specific Growth ◽  
Synthesis Rate ◽  
Specific Rate ◽  
Specific Growth Rates

Trichoderma reesei was cultivated in chemostat cultures on lactose-containing medium. The cultures were characterized for growth, consumption of the carbon source and protein production. Secreted proteins were produced most efficiently at low specific growth rates, 0·022–0·033 h−1, the highest specific rate of total protein production being 4·1 mg g−1 h−1 at the specific growth rate 0·031 h−1. At low specific growth rates, up to 29 % of the proteins produced were extracellular, in comparison to only 6–8 % at high specific growth rates, 0·045–0·066 h−1. To analyse protein synthesis and secretion in more detail, metabolic labelling of proteins was applied to analyse production of the major secreted protein, cellobiohydrolase I (CBHI, Cel7A). Intracellular and extracellular labelled CBHI was quantified and analysed for pI isoforms in two-dimensional gels, and the synthesis and secretion rates of the molecule were determined. Both the specific rates of CBHI synthesis and secretion were highest at low specific growth rates, the optimum being at 0·031 h−1. However, at low specific growth rates the secretion rate/synthesis rate ratio was significantly lower than that at high specific growth rates, indicating that at low growth rates the capacity of cells to transport the protein becomes limiting. In accordance with the high level of protein production and limitation in the secretory capacity, the transcript levels of the unfolded protein response (UPR) target genes pdi1 and bip1 as well as the gene encoding the UPR transcription factor hac1 were induced.

Estimating Bacterial Growth Parameters by Means of Detection Times

1999 ◽  
Vol 65 (2) ◽  
pp. 732-736 ◽  
Author(s):  
József Baranyi ◽  
Carmen Pin
Keyword(s):  
Growth Rate ◽  
Specific Growth Rate ◽  
Bacterial Growth ◽  
Specific Growth ◽  
Growth Parameters ◽  
Physiological State ◽  
Cell Number ◽  
Maximum Specific Growth Rate ◽  
Specific Rate ◽  
The Individual

ABSTRACT We developed a new numerical method to estimate bacterial growth parameters by means of detection times generated by different initial counts. The observed detection times are subjected to a transformation involving the (unknown) maximum specific growth rate and the (known) ratios between the different inoculum sizes and the constant detectable level of counts. We present an analysis of variance (ANOVA) protocol based on a theoretical result according to which, if the specific rate used for the transformation is correct, the transformed values are scattered around the same mean irrespective of the original inoculum sizes. That mean, termed the physiological state of the inoculum,α̂, and the maximum specific growth rate, μ, can be estimated by minimizing the variance ratio of the ANOVA procedure. The lag time of the population can be calculated as λ = −ln α̂/μ; i.e. the lag is inversely proportional to the maximum specific growth rate and depends on the initial physiological state of the population. The more accurately the cell number at the detection level is known, the better the estimate for the variance of the lag times of the individual cells.

Comparison of Actual and Potential Growth Rates of Brown Trout (Salmo trutta) in Natural Streams Based on Bioenergetic Models

1989 ◽  
Vol 46 (6) ◽  
pp. 1067-1076 ◽  
Author(s):  
Richard J. Preall ◽  
Neil H. Ringler
Keyword(s):  
Growth Rate ◽  
Specific Growth Rate ◽  
Brown Trout ◽  
Salmo Trutta ◽  
Specific Growth ◽  
Maximum Growth ◽  
Maximum Growth Rate ◽  
Dominant Feature ◽  
Natural Streams ◽  
Brown Trout Salmo Trutta

A ratio of specific growth rate to predicted maximum growth rate was employed as an ecological growth coefficient (EGC) in identifying major determinants of growth for brown trout, Salmo trutta, in natural streams. The coefficient may be more useful than specific growth rate when comparing trout populations from streams having diverse characteristics, since it accounts for the quantitative effects of stream temperature and mean trout weight. The maximum growth rate was generated by translating Elliott's bioenergetic equations into computer models applicable to fish weighing 5–300 g and to stream temperatures of 3.8–21.7 °C. EQMAX is the simpler model and generates only maximum growth rate. TROUT estimates the maximum ration size, maximum growth rate, and a variety of bioenergetic parameters. The EGC for Age I + trout ranged from 60 to 90% in three central New York streams. A relatively low EGC (30–60%) observed for Age II + trout in one stream may have been due to the inefficiency of feeding on small invertebrates. Temperature appears to be a dominant feature governing trout growth in streams. The bioenergetic models may provide useful predictions of the effects of foraging on prey communities by brown trout.

scholarly journals Determination of Specific Growth Rate by Measurement of Specific Rate of Ribosome Synthesis in Growing and Nongrowing Cultures of Acinetobacter calcoaceticus

2007 ◽  
Vol 74 (3) ◽  
pp. 901-903 ◽  
Author(s):  
Matthew R. Cutter ◽  
Peter G. Stroot
Keyword(s):  
Growth Rate ◽  
16S Rrna ◽  
Specific Growth Rate ◽  
Specific Growth ◽  
Acinetobacter Calcoaceticus ◽  
Microbial Populations ◽  
Specific Rate ◽  
Ribosome Synthesis ◽  
Good Agreement

ABSTRACT RT-RiboSyn measures the specific rate of ribosome synthesis in distinct microbial populations by measuring the generation rate of precursor 16S rRNA relative to that of mature 16S rRNA when precursor 16S rRNA processing is inhibited. Good agreement was demonstrated between specific rate of ribosome synthesis and specific growth rate of Acinetobacter calcoaceticus.

scholarly journals Microbial Interactions between Amylolytic and Non-Amylolytic Lactic Acid Bacteria Strains Isolated during the Fermentation of Pozol

2021 ◽  
Author(s):  
Sandra Bolaños-Nuñez ◽  
Jorge A. Santiago-Urbina ◽  
Jean-Pierre Guyot ◽  
Gloria Díaz-Ruiz ◽  
Carmen Wacher
Keyword(s):  
Growth Rate ◽  
Lactic Acid ◽  
Specific Growth Rate ◽  
Kinetic Parameters ◽  
Acid Production ◽  
Specific Growth ◽  
Lactic Acid Production ◽  
Amylolytic Activity ◽  
Specific Rate ◽  
Acid Yield

Pozol is a Mexican beverage prepared from fermented nixtamalized maize dough. To contribute to understanding its complex microbial ecology, the effect of inoculating on MRS-starch pure and mixed cultures of amylolytic Sii-25124 and non-amylolytic W. confusa 17, isolated from pozol, were studied on their interactions and fermentation parameters. These were compared with L. plantarum A6, an amylolytic strain isolated from cassava. Microbial growth, kinetic parameters, amylolytic activity, lactic acid production, and hydrolysis products from starch fermentation were measured. The population dynamics were followed by qPCR. L. plantarum A6 showed higher enzymatic activity, lactic acid, biomass production, and kinetic parameters than pozol LAB in pure cultures. Mixed culture of each pozol LAB with L. plantarum A6 showed a significant decrease in amylolytic activity, lactic acid yield, specific growth rate, and specific rate of amylase production. The interaction between Sii-25124 and W. confusa 17 increased the global maximum specific growth rate (µ), the lactic acid yield from starch (Ylac/s), lactic acid yield from biomass (Ylac/x), and specific rate of lactic acid production (qlac) by 15, 30, 30, and 40%, respectively compared with the pure culture of Sii-25124. Interactions between the two strains are essential for this fermentation.

scholarly journals Dynamics Modeling of Nitrogen Compounds in Microalgae Cells. 2. Chemostat

2019 ◽  
Vol 14 (2) ◽  
pp. 450-463 ◽  
Author(s):  
A.S. Lelekov ◽  
R.P. Trenkenshu
Keyword(s):  
Growth Rate ◽  
Specific Growth Rate ◽  
Specific Growth ◽  
Nitrogen Compounds ◽  
Specific Rate ◽  
Dynamics Modeling ◽  
Cell Content ◽  
Classical Models ◽  
Species Specific ◽  
Maximum Specific Rate

The work focuses on dynamics modeling of nitrogen compounds in microalgae cells under chemostat conditions. The analysis of classical models (Michaelis-Menten, Monod, Droop), which describe the kinetics of substrate-dependent growth of microalgae, was carried out. Classical models are shown to be applicable provided that the physicochemical parameters of the medium such as temperature, cell irradiation, etc are constant. As an alternative approach, the possibility of using linear splines in kinetics modeling of nitrate absorption by microalgae is shown. For the conditions of the chemostat, particular solutions for the generalized model of the dynamics of nitrogen compounds in the cells of microalgae considered in the first part of the work were obtained, and boundary conditions for the culture growth at unlimited nitrogen were determined. For limited growth, the equation for both the dependence of the specific growth rate on the intracellular nitrogen content, which coincides in form with the Droop model and the dependence of the specific growth rate on the extracellular concentration of nitrogen, which coincides in form with the Monod model were obtained. The species-specific coefficients of the equations such as the maximum specific rate of nitrogen absorption, the maximum specific rate of synthesis of structural components, the maximum content of reserve forms of nitrogen, the minimum share of structural forms of nitrogen in the total cell content were determined.

The growth and development of some barley varieties in response to irrigation and nitrogen fertilizer

1969 ◽  
Vol 72 (3) ◽  
pp. 467-474 ◽  
Author(s):  
E. J. M. Kirby
Keyword(s):  
Growth Rate ◽  
Specific Growth Rate ◽  
Leaf Area ◽  
Nitrogen Uptake ◽  
Nitrogen Fertilizer ◽  
Specific Growth ◽  
Leaf Growth ◽  
Specific Rate ◽  
High Fertility ◽  
Area Index

SUMMARYIn an experiment to investigate growth in relation to nitrogen concentration and nitrogen uptake, Proctor was compared with four other varieties of barley at two levels of irrigation and two levels of nitrogen fertilizer by means of weekly samples throughout the growing season. The varieties were Deba Abed, a new variety recommended for high fertility conditions where feeding quality grain is required, and three exotic varieties, chosen for their high concentration of nitrogen in the grain.Irrigation stimulated tillering, although certain varieties responded more strongly than others; irrigation also led to a higher specific growth rate. Certain of the exotic varieties had high growth rates early in the season but growth fell off earlier due to earlier ear emergence. Maximum leaf area index was greater in the irrigated treatment at the high nitrogen fertilizer level. The adapted varieties had higher maximum leaf area indices than the exotic varieties, although some of the exotics had higher rates of leaf area growth early in the season; there were also differences in the way in which the varieties responded to irrigation. Irrigation and variety both affected the rate at which the percentage nitrogen in the shoot fell with time.Analysis of these data indicates that nitrogen uptake early in the season was an important factor determining the total amount of nitrogen taken up by the plant. It was also shown that the relative rate of decline of the specific growth rate and the specific rate of nitrogen uptake differed between varieties. Analysis of the specific growth rate indicated that differences in leaf growth, rather than net assimilation rate, led to the varietal differences. The differential response to irrigation is discussed with reference to drought resistance.

scholarly journals Influence of Carbon Source on Nitrate Removal by Nitrate-TolerantKlebsiella oxytoca CECT 4460 in Batch and Chemostat Cultures

1998 ◽  
Vol 64 (8) ◽  
pp. 2970-2976 ◽  
Author(s):  
Guadalupe Piñar ◽  
Karin Kovárová ◽  
Thomas Egli ◽  
Juan L. Ramos
Keyword(s):  
Growth Rate ◽  
Specific Growth Rate ◽  
Specific Growth ◽  
Nitrate Removal ◽  
Dry Weight ◽  
Specific Rate ◽  
Continuous Cultures ◽  
Batch Cultures ◽  
Chemostat Cultures ◽  
C And N

ABSTRACT The nitrate-tolerant organism Klebsiella oxytoca CECT 4460 tolerates nitrate at concentrations up to 1 M and is used to treat wastewater with high nitrate loads in industrial wastewater treatment plants. We studied the influence of the C source (glycerol or sucrose or both) on the growth rate and the efficiency of nitrate removal under laboratory conditions. With sucrose as the sole C source the maximum specific growth rate was 0.3 h−1, whereas with glycerol it was 0.45 h−1. In batch cultures K. oxytocacells grown on sucrose or glycerol were able to immediately use sucrose as a sole C source, suggesting that sucrose uptake and metabolism were constitutive. In contrast, glycerol uptake occurred preferentially in glycerol-grown cells. Independent of the preculture conditions, when sucrose and glycerol were added simultaneously to batch cultures, the sucrose was used first, and once the supply of sucrose was exhausted, the glycerol was consumed. Utilization of nitrate as an N source occurred without nitrite or ammonium accumulation when glycerol was used, but nitrite accumulated when sucrose was used. In chemostat cultures K. oxytoca CECT 4460 efficiently removed nitrate without accumulation of nitrate or ammonium when sucrose, glycerol, or mixtures of these two C sources were used. The growth yields and the efficiencies of C and N utilization were determined at different growth rates in chemostat cultures. Regardless of the C source, yield carbon (YC) ranged between 1.3 and 1.0 g (dry weight) per g of sucrose C or glycerol C consumed. Regardless of the specific growth rate and the C source, yield nitrogen (YN) ranged from 17.2 to 12.5 g (dry weight) per g of nitrate N consumed. In contrast to batch cultures, in continuous cultures glycerol and sucrose were utilized simultaneously, although the specific rate of sucrose consumption was higher than the specific rate of glycerol consumption. In continuous cultures double-nutrient-limited growth appeared with respect to the C/N ratio of the feed medium and the dilution rate, so that for a C/N ratio between 10 and 30 and a growth rate of 0.1 h−1 the process led to simultaneous and efficient removal of the C and N sources used. At a growth rate of 0.2 h−1the zone of double limitation was between 8 and 11. This suggests that the regimen of double limitation is influenced by the C/N ratio and the growth rate. The results of these experiments were validated by pulse assays.

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