Growth Responses of Young Sockeye Salmon (Oncorhynchus nerka) to Different Diets and Planes of Nutrition

1971 ◽  
Vol 28 (10) ◽  
pp. 1635-1643 ◽  
Author(s):  
J. R. Brett
Keyword(s):  
Conversion Efficiency ◽  
Sockeye Salmon ◽  
Growth Response ◽  
Fish Meal ◽  
Oncorhynchus Nerka ◽  
Maximum Growth ◽  
Test Diet ◽  
Growth Responses ◽  
Marine Zooplankton ◽  
Conversion Efficiencies

The growth rate and food conversion efficiency of yearling sockeye salmon (Oncorhynchus nerka) (26 ± 2 g) was determined for Halver's test diet, Clark's Chinook mash, Abernathy pellets, frozen marine zooplankton, and sockeye mash, using a number of planes of nutrition. The maximum growth rates at 15 C varied from 3.1% dry body wt/day (Halver's) to 1.5%/day (marine zooplankton) with corresponding gross conversion efficiencies of 48 and 10%. Maintenance rations were determined, mostly by extrapolation, and used to evaluate the net conversion efficiency for each diet. The highest was 74% net conversion on Halver's test diet. Although major differences in growth response existed between the five diets, it was concluded that the various moist diets based on fish meal, used in these and earlier experiments, were not significantly different from each other when on the same plane of nutrition.

Growth Rate and Body Composition of Fingerling Sockeye Salmon, Oncorhynchus nerka, in relation to Temperature and Ration Size

1969 ◽  
Vol 26 (9) ◽  
pp. 2363-2394 ◽  
Author(s):  
J. R. Brett ◽  
J. E. Shelbourn ◽  
C. T. Shoop
Keyword(s):  
Growth Rate ◽  
Sockeye Salmon ◽  
Oncorhynchus Nerka ◽  
Maximum Growth ◽  
Maximum Growth Rate ◽  
Food Conversion ◽  
Lower Temperature ◽  
Ration Size ◽  
Conversion Efficiencies ◽  
Maintenance Ration

The growth of young sockeye salmon (Oncorhynchus nerka) was studied at temperatures ranging from 1 to 24 C in relation to rations of 0, 1.5, 3, 4.5, and 6% of dry body weight per day, and at an "excess" ration. Optimum growth occurred at approximately 15 C for the two highest rations, shifting progressively to a lower temperature at each lower ration. The maximum growth rate for sockeye 5–7 months old was 2.6%/day; that for fish 7–12 months old was 1.6%/day. At 1 C a ration of 1.5%/day was sufficient to provide for a maximum growth rate of 0.23%/day. The maintenance ration was found to increase rapidly above 12 C, amounting to 2.6%/day at 20 C. No growth took place at approximately 23 C despite the presence of excess food.Isopleths for gross and net food-conversion efficiencies were calculated. A maximum gross efficiency of 25% occurred in a small area with a center at 11.5 C and a ration of 4.0%/day; a maximum net efficiency of 40% occurred within a range of 8–10 C for rations of 1.5%/day down to 0.8%/day, the maintenance level.Gross body constituents changed in response to the imposed conditions, varying in extreme from 86.9% water, 9.4% protein, and 1.0% fat for starved fish at 20 C to 71.3% water, 19.7% protein, and 7.6% fat on an excess ration at 15 C.It is concluded on the basis of growth and food-conversion efficiency that temperatures from 5 to 17 C are most favorable for young sockeye, and that a general physiological optimum occurs in the vicinity of 15 C.

Effects of Sublethal Concentrations of Sodium Pentachlorophenate on Growth Rate, Food Conversion Efficiency, and Swimming Performance in Underyearling Sockeye Salmon (Oncorhynchus nerka)

1973 ◽  
Vol 30 (4) ◽  
pp. 499-507 ◽  
Author(s):  
P. W. Webb ◽  
J. R. Brett
Keyword(s):  
Growth Rate ◽  
Conversion Efficiency ◽  
Sockeye Salmon ◽  
Swimming Performance ◽  
Oncorhynchus Nerka ◽  
Dry Weight ◽  
Food Conversion ◽  
Ration Level ◽  
Sodium Pentachlorophenate ◽  
Sublethal Concentrations

Tests were performed at 15 C, pH 6.8, and dissolved oxygen values of 90–100% air saturation. Growth rate and conversion efficiency were measured by feeding a ration level of 15% body dry weight/day to underyearling sockeye salmon (Oncorhynchus nerka) held at sodium pentachlorophenate (PCP) concentrations of 0, 1.14, 1.99, 3.49, 7.16, 13.60, 27.73, 31.57, and 47.18 ppb. Swimming performance was measured at PCP concentrations of 0, 7.21, 19.00, and 50.00 ppb. The 96-hr LC50 was 63 ppb PCP. Growth rate and conversion efficiency were almost equally affected by PCP, the EC50 values being 1.74 ppb for growth rate and 1.80 ppb for conversion efficiency. This is approximately 2.8% of the 96-hr LC50. Swimming performance was unaffected by PCP at the concentrations used.

Model of Monthly Marine Growth and Natural Mortality for Babine Lake Sockeye Salmon (Oncorhynchus nerka)

1986 ◽  
Vol 43 (5) ◽  
pp. 999-1004 ◽  
Author(s):  
Donald J. Furnell ◽  
J. R. Brett
Keyword(s):  
Sockeye Salmon ◽  
Environmental Temperature ◽  
Oncorhynchus Nerka ◽  
Inverse Function ◽  
Fish Mortality ◽  
Natural Mortality ◽  
Growth Responses ◽  
Major Life ◽  
Cultured Fish ◽  
Mortality Estimates

Monthly marine growth and natural mortality rates were calculated for each major life history type of Babine Lake sockeye salmon (Oncorhynchus nerka) and compared with estimates by other methods. Growth rates were based on sizes at the beginning and end of each marine year and adjusted according to seasonal changes in environmental temperature. Temperature effects were derived from information on growth responses of cultured fish. Mortality estimates were based on a model which equates mortality rate to an inverse function of weight. Monthly sizes determined from the growth model were substituted into the mortality model, together with estimates of smolt and adult runs (catch plus escapement), to examine the population dynamics of an average Babine Lake smolt cohort. Using these predictions we suggest that 90% of natural mortality occurred during the first 4 mo at sea.

Dormancy and Impotency of Cocklebur Seeds. VI. Growth and Ethylene Production of Cotyledon Segments in Response to Oxygen

1976 ◽  
Vol 3 (5) ◽  
pp. 711 ◽  
Author(s):  
Y Esashi ◽  
K Kotaki ◽  
O Ishidoya
Keyword(s):  
Seed Germination ◽  
Ethylene Production ◽  
Growth Response ◽  
Maximum Growth ◽  
Growth Responses ◽  
Cooperative Action ◽  
Water Imbibition ◽  
Oxygen Tensions

Cotyledon tissue excised from dormant or non-dormant large cocklebur (Xanthium pensylvanicum Wallr.) seeds were examined for growth responses to CO2 or ethylene and for ethylene production under different oxygen tensions. Regardless of the dormancy status, cotyledons responded to CO2 and ethylene in a very similar manner to axes: the maximum growth response to CO2 and ethylene was obtained in quasi-anaerobioses in the case of the non-dormant cotyledons, but in increased oxygen tensions in the case of the dormant ones. A cooperative action of CO2 and ethylene was prominent in the presence of oxygen in suitable amounts. CO2 began to exert an effect first after water imbibition, then ethylene and lastly oxygen was needed to allow normal cotyledon growth. As the ethylene-producing system of cotyledons, active in quasi-anaerobioses, differed from that of axes in requirement for oxygen, the enhancement of ethylene production by exogenous CO2 was greater under reduced rather than increased oxygen tensions. Finally, the possible mechanism of cocklebur seed germination in subterranean habitats was discussed from the likely involvement of these three gaseous factors in axial and cotyledonary growth.

Scope for Metabolism and Growth of Sockeye Salmon, Oncorhynchus nerka, and Some Related Energetics

1976 ◽  
Vol 33 (2) ◽  
pp. 307-313 ◽  
Author(s):  
J. R. Brett
Keyword(s):  
Growth Rate ◽  
Sockeye Salmon ◽  
Oncorhynchus Nerka ◽  
Maximum Growth ◽  
General Concept ◽  
Maximum Growth Rate ◽  
Scope For Growth ◽  
Metabolic Scope ◽  
The Difference

The extent of metabolic and feeding requirements for fingerling sockeye salmon (Oncorhynchus nerka) are compared over the tolerable range of temperature. Scope for growth, derived from the difference between maximum and maintenance rations, is shown to relate to temperature in a manner similar to that for maximum growth rate. Metabolic scope is compared with scope for growth, supporting the general concept of scope for activity developed by Fry (1947).

scholarly journals Thermoelectric Generation with Impinging Nano-Jets

Energies ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 492
Author(s):  
Fatih Selimefendigil ◽  
Hakan F. Oztop ◽  
Mikhail A. Sheremet
Keyword(s):  
Fluid Dynamics ◽  
Power Generation ◽  
Computational Fluid Dynamics ◽  
Reynolds Number ◽  
Conversion Efficiency ◽  
Reynolds Numbers ◽  
Thermoelectric Generation ◽  
Volume Fractions ◽  
Water Jets ◽  
Conversion Efficiencies

In this study, thermoelectric generation with impinging hot and cold nanofluid jets is considered with computational fluid dynamics by using the finite element method. Highly conductive CNT particles are used in the water jets. Impacts of the Reynolds number of nanojet stream combinations (between (Re1, Re2) = (250, 250) to (1000, 1000)), horizontal distance of the jet inlet from the thermoelectric device (between (r1, r2) = (−0.25, −0.25) to (1.5, 1.5)), impinging jet inlet to target surfaces (between w2 and 4w2) and solid nanoparticle volume fraction (between 0 and 2%) on the interface temperature variations, thermoelectric output power generation and conversion efficiencies are numerically assessed. Higher powers and efficiencies are achieved when the jet stream Reynolds numbers and nanoparticle volume fractions are increased. Generated power and efficiency enhancements 81.5% and 23.8% when lowest and highest Reynolds number combinations are compared. However, the power enhancement with nanojets using highly conductive CNT particles is 14% at the highest solid volume fractions as compared to pure water jet. Impacts of horizontal location of jet inlets affect the power generation and conversion efficiency and 43% variation in the generated power is achieved. Lower values of distances between the jet inlets to the target surface resulted in higher power generation while an optimum value for the highest efficiency is obtained at location zh = 2.5ws. There is 18% enhancement in the conversion efficiency when distances at zh = ws and zh = 2.5ws are compared. Finally, polynomial type regression models are obtained for estimation of generated power and conversion efficiencies for water-jets and nanojets considering various values of jet Reynolds numbers. Accurate predictions are obtained with this modeling approach and it is helpful in assisting the high fidelity computational fluid dynamics simulations results.

Resumption of anadromy or straying? Origins of Sockeye Salmon Oncorhynchus nerka in the Elwha River

2021 ◽  
Author(s):  
Thomas P. Quinn ◽  
George R. Pess ◽  
Ben J.G. Sutherland ◽  
Samuel J. Brenkman ◽  
Ruth E. Withler ◽  
...  
Keyword(s):  
Sockeye Salmon ◽  
Oncorhynchus Nerka ◽  
Elwha River

Alternative Recruitment Models of Adams River Sockeye Salmon, Oncorhynchus nerka

1987 ◽  
Vol 44 (9) ◽  
pp. 1551-1561 ◽  
Author(s):  
Jeremy S. Collie ◽  
Carl J. Walters
Keyword(s):  
Sockeye Salmon ◽  
Oncorhynchus Nerka ◽  
Status Quo ◽  
Management Policy ◽  
Best Management ◽  
Interaction Terms ◽  
Ricker Model ◽  
The Status ◽  
Stock Recruitment ◽  
High Yields

Despite evidence of depensatory interactions among year-classes of Adams River sockeye salmon (Oncorhynchus nerka), the best management policy is one of equal escapement for all year-classes. We fit alternative models (Ricker model and Larkin model) to 32 yr of stock–recruitment data and checked, using simulation tests, that the significant interaction terms in the Larkin model are not caused by biases in estimating the parameters. We identified a parameter set (Rationalizer model) for which the status quo cyclic escapement policy is optimal, but this set fits the observed data very poorly. Thus it is quite unlikely that the Rationalizer model is correct or that the status quo escapement policy is optimal. Using the fitted stock–recruitment parameters, we simulated the sockeye population under several management policies. The escapement policy optimal under the Ricker model is best overall because of the high yields if it should be correct. If the three stock–recruitment models are equally likely to be correct, the simulations predict that adopting a constant-escapement policy would increase long-term yield 30% over the current policy and that an additional 15% increase in yield could be obtained if the policy were actively adaptive.

Reduced growth in wild juvenile sockeye salmon Oncorhynchus nerka infected with sea lice

2017 ◽  
Vol 91 (1) ◽  
pp. 41-57 ◽  
Author(s):  
S. C. Godwin ◽  
L. M. Dill ◽  
M. Krkošek ◽  
M. H. H. Price ◽  
J. D. Reynolds
Keyword(s):  
Sockeye Salmon ◽  
Oncorhynchus Nerka ◽  
Sea Lice
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