The growth rate and growth efficiency of Streptocephalus macrourus (Crustacea, Anostraca) cultured on microalgae

The physiological rates of a normally omnivorous marine rotifer, Encentrum linnhei, were measured under the steady-state chemostat conditions in which the physiological state of the food-algae was kept constant whilst the rotifer growth rate was changed to preset levels. The specific clearance rate ranged between 50 and 100 μl/μg rotifer C/day (1.5–3.0 μ/rot/day) and varied hyperbolically with growth rate, a similar curve was obtained with the specific ingestion rate which varied between 1–2 μg C/μg rot C/day. A mean respiration rate of 0.45 μg C/μg rot C/day was obtained from oxygen consumption measurements. About 60‰ of ingested energy was found to be egested as paniculate matter and 9–4 °0 dissipated as heat, the latter comparing with a theoretical figure of 4–5‰.From rates, transfer efficiencies were obtained giving a mean net growth efficiency (K2) of 38‰ and a mean overall growth efficiency (K1 of 15‰. A curvilinear increase of Kl with growth rate contrasts with linear and hyperbolic responses found with brachionid rotifers.

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Energy Dynamics of the Eutrophic Chironomid Chironomus plumosus f. semireductus from the Bay of Quinte, Lake Ontario

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f80-161 ◽

1980 ◽

Vol 37 (8) ◽

pp. 1254-1265 ◽

Cited By ~ 20

Author(s):

Ora E. Johannsson

Keyword(s):

Growth Rate ◽

Feeding Rate ◽

Assimilation Efficiency ◽

Growth Efficiency ◽

Time Of Day ◽

Organic Content ◽

Algal Community ◽

Instantaneous Growth Rate ◽

Larval Size ◽

Instantaneous Growth

Relationships between feeding rate, temperature, body size, and time of day were investigated and collated with seasonal assimilation efficiencies of in situ chironomids to construct a picture of chironomid energetics over the year. Temperature controlled feeding rate, and larval size and time of day exerted no effect. The temperature optimum plateaued between 22.0 and 24.5 °C, decreasing logarithmically outside this range. Both assimilation efficiency (AE) and organic content of the food varied seasonally, but were not correlated. Periods of high AE corresponded with the latter part of Melosira or Melosira–Stephanodiscus blooms, while periods of low AE occurred between diatom blooms and during the late summer blue-green bloom. Consequently, growth fluctuated throughout the year, being a result of the interaction of temperature and AE. Anabolic processes dominated at AE greater than 3.5%. Maximum net growth efficiency (NGE) was attained when AE ≥ 6% and temperature ≥ 15 °C. NGE was more sensitive to changes in AE than temperature. Instantaneous growth rate, however, was more sensitive to changes in temperature. Daily ingestion (mg) exceeded body weight by as much as 460–480%, which equals the sediment-processing capacity of freshwater detritivores.Key words: chironomid, feeding rate, assimilation efficiency, instantaneous growth rate, net growth efficiency, algal community, Bay of Quinte

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Ingestion-Limited Growth of Aquatic Animals: The Case for Blackman Kinetics

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f82-214 ◽

1982 ◽

Vol 39 (12) ◽

pp. 1585-1595 ◽

Cited By ~ 17

Author(s):

Richard E. Condrey

Keyword(s):

Growth Rate ◽

Linear Relationship ◽

Ingestion Rate ◽

Growth Efficiency ◽

Published Data ◽

Limited Growth ◽

Aquatic Animals

The published data on ingestion-limited growth in aquatic animals is shown to be consistent with Blackman kinetics. As such, if ingestion limits growth rate there is a linear relationship between growth and ingestion from starvation to satiation. If, however, growth is limited by some factor other than ingestion rate, there is no increase in growth rate with increasing ingestion rate.Key words: ingestion, growth, growth efficiency, Blackman kinetics

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OPTIMAL TERRITORY SIZE IN THE CONVICT CICHLID

Behaviour ◽

10.1163/156853999500767 ◽

1999 ◽

Vol 136 (10-11) ◽

pp. 1347-1363 ◽

Cited By ~ 17

Author(s):

James W.A. Grant ◽

Jason Praw

Keyword(s):

Growth Rate ◽

Social Stress ◽

Patch Size ◽

Growth Efficiency ◽

Food Abundance ◽

Territory Size ◽

Initial Increase ◽

Archocentrus Nigrofasciatus ◽

Convict Cichlids ◽

Intermediate Size

AbstractModels of optimal territory size are usually tested only by demonstrating that territory size is inversely related to food abundance or intruder number. The most fundamental predictions of the models, however, have rarely been tested: i.e. the fitness of the defender is a function of territory size and the optimal territory is one of intermediate size. We tested these predictions by measuring the growth rate of large convict cichlids (Archocentrus nigrofasciatus, formerly Cichlasoma nigrofasciatum) while defending food patches against smaller intruders over a 10-day period. Food patches differed in area by more than two orders of magnitude. We manipulated food abundance so that it increased with patch size in a decelerating way. As assumed, the realized benefits of defence (weight of food eaten by the defender) and the costs of defence (chase rate and chase radius) both increased in a decelerating way with increasing patch area. As predicted, the growth rate of the defender first increased and then decreased with increasing patch size. The initial increase in defender growth rate with increasing patch size was related to an increase in food eaten, but the decrease in growth rate for fish defending the largest patches was related to the costs of defence. Fish defending large patches had a low growth efficiency, apparently because of the social stress caused by intruders in their territories. Taken together, these results support the assumptions and predictions of optimal territory size models.

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Microzooplankton functional responses in the lab and in the field

Earth System Science Data Discussions ◽

10.5194/essdd-7-149-2014 ◽

2014 ◽

Vol 7 (1) ◽

pp. 149-167 ◽

Cited By ~ 2

Author(s):

S. F. Sailley ◽

E. T. Buitenhuis

Keyword(s):

Growth Rate ◽

Functional Response ◽

Laboratory Experiments ◽

Nutrient Content ◽

Growth Efficiency ◽

External Factors ◽

Data Sets ◽

Functional Responses ◽

Prey Concentration ◽

Gross Growth Efficiency

Abstract. We present a collection of data relating to microzooplankton physiological traits collected from the literature. We define microzooplankton as unicellular zooplankton (protozoans). The collected data mostly relates to grazing rates collected either in the field or through laboratory experiments. There is an equal number of grazing and growth rate measured through laboratory experiments and a smaller number of Gross Growth Efficiency (GGE), respiration and egestion values. Although the collected data showed inconsistencies in units, or gaps in knowledge of microzooplankton (e.g. effect of prey nutrient content, combined measurement of grazing and growth), they also contained information on microzooplankton functional response, and how some external factors affect them (e.g. prey concentration, prey offered, temperature). Link to the repository: doi:10.1594/PANGAEA.820368 and doi:10.1594/PANGAEA.826106. Note that the sum of all data sets differs from the present data compilations which provides harmonized units and temperature adjusted metabolic. Within the repository there is a link to the "raw" dataset.

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Trait-based approach to bacterial growth efficiency

10.1101/427161 ◽

2018 ◽

Cited By ~ 6

Author(s):

Mario E. Muscarella ◽

Xia Meng Howey ◽

Jay T. Lennon

Keyword(s):

Growth Rate ◽

Bacterial Growth ◽

Maximum Growth ◽

Growth Efficiency ◽

Maximum Growth Rate ◽

Bacterial Growth Efficiency ◽

Species Identity ◽

Trade Offs ◽

Aggregate Property ◽

Resource Type

AbstractBacterial growth efficiency (BGE) is the proportion of assimilated carbon that is converted into biomass and reflects the balance between growth and energetic demands. Often measured as an aggregate property of the community, BGE is highly variable within and across ecosystems. To understand this variation, we first identified how species identity and resource type affect BGE using 20 bacterial isolates belonging to the phylum Proteobacteria that were enriched from north temperate lakes. Using a trait-based approach that incorporated genomic and phenotypic information, we characterized the metabolism of each isolate and tested for predicted trade-offs between growth rate and efficiency. A substantial amount of variation in BGE could be explained at both broad (i.e., order, 20 %) and fine (i.e., strain, 58 %) taxonomic levels. While resource type was a relatively weak predictor across species, it explained > 60 % of the variation in BGE within a given species. Furthermore, a metabolic trade-off (between maximum growth rate and efficiency) and genomic features revealed that BGE is a predictable metabolic feature. Our study suggests that genomic and phylogenetic information may help predict aggregate microbial community functions like BGE and the fate of carbon in ecosystems.Originality and SignificanceBacterial growth efficiency (BGE) is an important yet notoriously variable measure of metabolism that has proven difficult to predict. To better understand how assimilated carbon is allocated, we explored growth efficiency across a collection of bacteria strains using a trait-based approach. Specifically, we measured respiration and biomass formation rates for populations grown in minimal media containing one of three carbon resources. In addition, we collected a suite of physiological traits to describe each strain, and we sequenced the genome of each organism. Our results suggest that species identity and resource type may contribute to growth efficiency when measured as an aggregate property of a natural community. In addition, we identified genomic pathways that are associated with elevated BGE. The findings have implications for integrating microbial metabolism from the cellular to ecosystem scale.

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Effect of growth rate of the food alga on the growth/ingestion efficiency of a marine herbivore

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315400040376 ◽

1980 ◽

Vol 60 (3) ◽

pp. 681-702 ◽

Cited By ~ 65

Author(s):

J. M. Scott

Keyword(s):

Growth Rate ◽

Growth Rates ◽

Biochemical Composition ◽

Brachionus Plicatilis ◽

Calorific Value ◽

Growth Efficiency ◽

Food Alga ◽

Marine Herbivore

The chlorophycean alga, Brachiomonas submarina var. pulsifera Droop, was grown in two bacteria-free chemostats, differing only in the amount of light each received. Investigations were made into the changes in biochemical composition and calorific value of the cells when they were grown at different growth rates. This information was used to help to explain changes in the growth efficiency of the rotifer Brachionus plicatilis Miiller, grown in a bacteria-free chemostat which was linked to one of the algal chemostats, the algae being supplied as the source of food.

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Influence of Plant Population and Nitrogen-Fertilizer at Various Levels on Growth and Growth Efficiency of Maize

The Scientific World JOURNAL ◽

10.1155/2013/193018 ◽

2013 ◽

Vol 2013 ◽

pp. 1-9 ◽

Cited By ~ 12

Author(s):

M. I. Tajul ◽

M. M. Alam ◽

S. M. M. Hossain ◽

K. Naher ◽

M. Y. Rafii ◽

...

Keyword(s):

Growth Rate ◽

Field Experiments ◽

Plant Density ◽

Maximum Yield ◽

Growth Efficiency ◽

Plant Population ◽

Yield Attributes ◽

Relative Growth ◽

Spad Value ◽

N Rates

Field experiments were conducted to evaluate plant population and N-fertilizer effects on yield and yield components of maize (Zea maysL.). Three levels of plant populations (53000, 66000, and 800000 plants ha−1corresponding to spacings of 75 × 25, 60 × 25, and 50 × 25 cm) and 4 doses of N (100, 140, 180, and 220 kg ha−1) were the treatment variables. Results revealed that plant growth, light interception (LI), yield attributes, and grain yield varied significantly due to the variations in population density and N-rates. Crop growth rate (CGR) was the highest with the population of 80,000 ha−1receiving 220 kg N ha−1, while relative growth rate (RGR) showed an opposite trend of CGR. Light absorption was maximum when most of densely populated plant received the highest amount of N (220 kg N ha−1). Response of soil-plant-analysis development (SPAD) value as well as N-content to N-rates was found significant. Plant height was the maximum at the lowest plant density with the highest amount of N. Plants that received 180 kg N ha−1with 80,000 plants ha−1had larger foliage, greater SPAD value, and higher amount of grains cob−1that contributed to the maximum yield (5.03 t ha−1) and the maximum harvest index (HI) compared to the plants in other treatments.

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