Seasonal Variation in Weight-Specific Growth Rates, Feeding Rates, and Growth Efficiencies in Microgadus tomcod

1983 ◽  
Vol 40 (12) ◽  
pp. 2197-2200 ◽  
Author(s):  
I. M. Salinas ◽  
I. A. McLaren
Keyword(s):  
Specific Growth ◽  
Growth Efficiency ◽  
Bay Of Fundy ◽  
Feeding Rates ◽  
Annual Basis ◽  
Feeding Experiments ◽  
Length Relationship ◽  
Specific Growth Rates ◽  
Microgadus Tomcod ◽  
Summer Feeding

Among Microgadus tomcod from Cumberland Basin, Bay of Fundy, exponents of the weight–length relationship (liver, gonads removed) ranged from 2.74 in April, after spawning, to 3.47 in September, after summer feeding. This implies that growth rate per unit of weight is seasonally higher in larger fish, although this diminishes on an annual basis after 2 yr in these short-lived (< 4 yr) fish. In feeding experiments larger fish after spawning increased feeding (weight-specific ration declined with weight in September, not in April-May) and grew faster, using proportionately more food for growth (growth efficiency not correlated with weight in September, positively so in April–May).

scholarly journals Multi-omics approach to study the growth efficiency and amino acid metabolism in Lactococcus lactis at various specific growth rates

2011 ◽  
Vol 10 (1) ◽  
pp. 12 ◽  
Author(s):  
Petri-Jaan Lahtvee ◽  
Kaarel Adamberg ◽  
Liisa Arike ◽  
Ranno Nahku ◽  
Kadri Aller ◽  
...  
Keyword(s):  
Amino Acid ◽  
Lactococcus Lactis ◽  
Growth Rates ◽  
Amino Acid Metabolism ◽  
Acid Metabolism ◽  
Specific Growth ◽  
Growth Efficiency ◽  
Specific Growth Rates

Oscillating conditions for influencing the composition of mixed biological cultures

1998 ◽  
Vol 37 (4-5) ◽  
pp. 259-262 ◽  
Author(s):  
Bjarne R. Horntvedt ◽  
Morten Rambekk ◽  
Rune Bakke
Keyword(s):  
Growth Rate ◽  
Specific Growth ◽  
Heterotrophic Bacteria ◽  
Bacterial Species ◽  
Rate Reduction ◽  
Similar Strategy ◽  
Sinusoidal Oscillations ◽  
Specific Growth Rates ◽  
Rate Limiting ◽  
Concentration Levels

This paper presents a strategy in which mixed biological cultures are exposed to oscillating concentration levels, to improve the potential for coexistence of desired bacterial species. A mechanistic mathematical model is constructed to investigate and illustrate this strategy. This paper is focused on competition between nitrifying, denitrifying and aerobic heterotrophic bacteria in a CSTR with sludge recycle. For nitrifying and aerobic heterotrophic cultures, the effect of sinusoidal oscillations in DO levels with an amplitude of 1.0 mg/l is a 16% specific growth rate reduction compared to that at a constant DO level. The denitrifiers growth rate is increased by an average of 59%, compared to the constant DO level situation. A similar strategy has been tested in a pilot plant. It is concluded that the influence on specific growth rates is a function of the amplitude of the oscillations. The effects are greatest when concentrations fluctuate around the half saturation concentration of the rate limiting component(s).

Effects of turbidity on prey consumption and growth in brook trout and implications for bioenergetics modeling

2001 ◽  
Vol 58 (2) ◽  
pp. 386-393 ◽  
Author(s):  
John A Sweka ◽  
Kyle J Hartman
Keyword(s):  
Growth Rates ◽  
Brook Trout ◽  
Specific Growth ◽  
Abiotic Factors ◽  
Foraging Strategies ◽  
Turbid Water ◽  
Daily Consumption ◽  
Consumption Rates ◽  
The Difference ◽  
Specific Growth Rates

Brook trout (Salvelinus fontinalis) were held in an artificial stream to observe the influence of turbidity on mean daily consumption and specific growth rates. Treatment turbidity levels ranged from clear (<3.0 nephelometric turbidity units (NTU)) to very turbid water (> 40 NTU). Observed mean daily specific consumption rates were standardized to the mean weight of all brook trout tested. Turbidity had no significant effect on mean daily consumption, but specific growth rates decreased significantly as turbidity increased. Brook trout in turbid water became more active and switched foraging strategies from drift feeding to active searching. This switch was energetically costly and resulted in lower specific growth rates in turbid water as compared with clear water. Bioenergetics simulations were run to compare observed growth with that predicted by the model. Observed growth values fell below those predicted by the model and the difference increased as turbidity increased. Abiotic factors, such as turbidity, which bring about changes in the activity rates of fish, can have implications for the accuracy of predicted growth by bioenergetics models.

The effect of energy and nitrogen supply pattern on rumen bacterial growthin vitro

1991 ◽  
Vol 53 (2) ◽  
pp. 165-175 ◽  
Author(s):  
P. H. Henning ◽  
D. G. Steyn ◽  
H. H. Meissner
Keyword(s):  
Bacterial Growth ◽  
Specific Growth ◽  
Growth Efficiency ◽  
Bacterial Growth Efficiency ◽  
Batch Cultures ◽  
Time Zero ◽  
N Supply ◽  
Pulse Dose ◽  
Supply Pattern ◽  
Glucose Supply

AbstractThe effect of energy and nitrogen (N) supply pattern on rumen bacterial growth was investigated in vitro. In experiment 1, glucose was was fed to batch cultures of mixed rumen bacteria according to three patterns namely a pulse dose at time zero (P); even increments at 0·5-h intervals (G) or an intermediate pattern (I), whilst N was supplied in excess. In experiment 2, glucose and N (not in excess) were fed to batch cultures according to four patterns namely glucose and N as pulse doses at time zero, (EPNP); glucose as a pulse dose at time zero and N in 24 even increments at 0·5-h intervals (EPNG); glucose in 24 even increments at 0·5-h intervals and N as a pulse dose at time zero (EGNP) or both glucose and N in 24 even increments at 0·5-h intervals (EGNG). Fermentaton was studied over a 12-h period for both experiments.In experiment 1, bacterial growth efficiency and specific growth rate (39·8,35·5 and 29·9 (g bacterial dry matter (DM) per mol glucose utilized) and 0·33, 0·27 and 0·20 (fraction per h) for treatments P, I, and G respectively) differed significantly between glucose supply patterns. In experiment 2, bacterial growth efficiency and specific growth rate (33·8, 34·7, 25·9 and 22·5 (g baterial DM per mol glucose) and 0·21, 0·18, 0·14 and 0·13 (fraction per h) for treatments EPNP, EPNG, EGNP and EGNG respectively) differed significantly only between glucose supply patterns.It is concluded that the pattern according to which a given amount of energy becomes available affects bacterial growth efficiency, with the fastest supply rate giving the highest efficiency and that, within accepted levels of N supply, synchronization between energy and N availability may be of less importance to bacterial growth efficiency than the energy supply pattern.

Sex Ratio and Sex-Specific Growth Rates of Immature Green Turtles, Chelonia mydas, in the Southern Bahamas

Copeia ◽  
1992 ◽  
Vol 1992 (4) ◽  
pp. 1098 ◽  
Author(s):  
Alan B. Bolten ◽  
Karen A. Bjorndal ◽  
Janice S. Grumbles ◽  
David W. Owens
Keyword(s):  
Sex Ratio ◽  
Growth Rates ◽  
Specific Growth ◽  
Chelonia Mydas ◽  
Green Turtles ◽  
Specific Growth Rates

Physiological and cell morphology adaptation ofBacillus subtilisat near-zero specific growth rates: a transcriptome analysis

2014 ◽  
Vol 17 (2) ◽  
pp. 346-363 ◽  
Author(s):  
Wout Overkamp ◽  
Onur Ercan ◽  
Martijn Herber ◽  
Antonius J. A. van Maris ◽  
Michiel Kleerebezem ◽  
...  
Keyword(s):  
Cell Morphology ◽  
Transcriptome Analysis ◽  
Growth Rates ◽  
Specific Growth ◽  
Specific Growth Rates

Biology of Oscillatoria cf. chalybea, a 2-methylisoborneol producing blue-green alga of Mississippi catfish ponds

1995 ◽  
Vol 31 (11) ◽  
pp. 173-180 ◽  
Author(s):  
M. van der Ploeg ◽  
M. E. Dennis ◽  
M. Q. de Regt
Keyword(s):  
Growth Rate ◽  
Specific Growth ◽  
Light Availability ◽  
Continuous Light ◽  
Light Cycle ◽  
Blue Green Alga ◽  
Continuous Cultures ◽  
Effects Of Temperature ◽  
Catfish Ponds ◽  
Specific Growth Rates

Relative abundance of Oscillatoria cf. chalybea was monitored during May-November, 1993, in 40 ponds at four catfish farms located 50-100 km apart in west central Mississippi, USA. The occurrence of O. cf.chalybea coincided with the period that water temperatures remained above 20°C. In 70% of ponds, O. cf.chalybea was present for a period of 2-20 weeks. The alga recurred in all ponds where it had been present in 1990 and 1991. The effects of temperature and light availability on growth rate and 2-methylisoborneol (MIB) production of O. cf. chalybea were studied in continuous cultures. At 28°C, maximum specific growth rates were 0.8 d−1 (24 h light) and 0.6 d−1 (14 h light :10 h dark). Algal cells contained less MIB when adapted to the shorter light cycle than when grown under continuous light. Specific growth rate of O. cf.chalybea dropped from 0.3 to 0.1 d−1 when temperature was changed from 21 to 19.5°C (14 h light).

Energy Flow and Secondary Production of the Amphipods Hyalella azteca and Crangonyx richmondensis occidentalis in Marion Lake, British Columbia

1971 ◽  
Vol 28 (5) ◽  
pp. 711-726 ◽  
Author(s):  
Jack A. Mathias
Keyword(s):  
Population Growth ◽  
Energy Flow ◽  
Standing Crop ◽  
Production Efficiency ◽  
Hyalella Azteca ◽  
Growth Efficiency ◽  
Ecological Efficiency ◽  
Net Production ◽  
Annual Basis ◽  
Predator System

The Hyalella azteca population in Marion Lake, B.C., assimilated and produced about three times as much energy as did the Crangonyx richmondensis occidentalis population from May 1966 to May 1967, but during the summer the energy flow of H. azteca was four times, and production was five times, that of C. r. occidentalis.Hyalella azteca was abundant at a depth of 1.0 m (mean summer standing crop, 1952 animals/m2), but was rare (75 animals/m2) at depths greater than 2.5 m. Growth, molting, respiration, and hence energy flow rates decreased with depth, due (in part) to lower ambient temperatures in deeper water. On an annual basis, a mean standing crop of 1.1 kcal/m2 of H. azteca assimilated 18.1 kcal/m2, respired 13.5 kcal/m2, and used 4.6 kcal/m2 in production of growth, molts, and eggs. Approximately two-thirds of the annual energy flow was completed between June and October. On an annual basis, the ecological efficiency of an H. azteca-predator system was in the range 2.5–12.5%, the net production efficiency was 25%, and the net population growth efficiency was 16%.The mean summer density of C. r. occidentalis remained constant with depth (about 283 animals/m2). Annual energy flow and production were not appreciably affected by lower temperatures in deeper water. On an annual basis, a mean standing crop of 0.7 kcal/m2 assimilated 6.5 kcal/m2, respired 5.2 kcal/m2, and used 1.4 kcal/m2 in production. Crangonyx r. occidentalis energy flow was fairly constant throughout the year. The ecological efficiency of a C. r. occidentalis-predator system was in the range 2–10.5%, the net production efficiency was 21%, and the population growth efficiency was 17% on an annual basis.

Differential effects of turbidity on prey consumption of piscivorous and planktivorous fish

2003 ◽  
Vol 60 (12) ◽  
pp. 1517-1526 ◽  
Author(s):  
Alex De Robertis ◽  
Clifford H Ryer ◽  
Adriana Veloza ◽  
Richard D Brodeur
Keyword(s):  
Light Intensity ◽  
Prey Capture ◽  
High Light Intensity ◽  
Prey Consumption ◽  
Planktivorous Fish ◽  
Oncorhynchus Keta ◽  
Feeding Rates ◽  
Anoplopoma Fimbria ◽  
Piscivorous Fish ◽  
Feeding Experiments

Contrast degradation theory predicts that increased turbidity decreases the visibility of objects that are visible at longer distances more than that of objects that are visible at short distances. Consequently, turbidity should disproportionately decrease feeding rates by piscivorous fish, which feed on larger and more visible prey than particle-feeding planktivorous fish. We tested this prediction in a series of laboratory feeding experiments, the results of which indicated that prey consumption by two species of planktivorous fish (juvenile chum salmon (Oncorhynchus keta) and walleye pollock (Theragra chalcogramma)) is much less sensitive to elevated turbidity than piscivorous feeding by sablefish (Anoplopoma fimbria). Planktivorous feeding in the turbidity range tested (0–40 nephelometric turbidity units (NTU)) was reduced at high light intensity, but not at low light intensity. Comparatively low (5–10 NTU) turbidity decreased both the rate at which sablefish pursued prey and the probability of successful prey capture. These results suggest that turbid environments may be advantageous for planktivorous fish because they will be less vulnerable to predation by piscivores, but will not experience a substantial decrease in their ability to capture zooplankton prey.

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