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.

The Effects of Sublethal Concentrations of Whole Bleached Kraftmill Effluent on the Growth and Food Conversion Efficiency of Underyearling Sockeye Salmon (Oncorhynchus nerka)

1972 ◽  
Vol 29 (11) ◽  
pp. 1555-1563 ◽  
Author(s):  
P. W. Webb ◽  
J. R. Brett
Keyword(s):  
Growth Rate ◽  
Conversion Efficiency ◽  
Sockeye Salmon ◽  
Condition Factor ◽  
Dry Weight ◽  
Food Conversion ◽  
Response Curves ◽  
Threshold Response ◽  
Exposure Temperature ◽  
Sublethal Concentrations

Changes in growth rate and gross conversion efficiency were measured for underyearling sockeye salmon during and after exposure to full bleached kraftmill effluent (BKME). Five groups of fish were exposed for 56 days to 0, 1.0, 2.5, 10, and 25% BKME (v/v). Fresh 24-hr composite effluent at pH 6.8 was used daily after filtering. Growth was followed for a further 56 days after BKME exposure. Temperature was held at 15 C and dissolved oxygen between 90 and 100% air saturation. Growth rate and conversion efficiency were unaffected at 1.0 and 2.5% BKME. Reduced mean growth rate and conversion efficiency at 10% BKME were not statistically significant from controls but were considered to be biologically important in estimating threshold response levels. Significant reductions were found at 25% BKME. No recovery in retarded growth was found after exposure to BKME. Condition factor and percentage dry weight were not affected. It was concluded from computed response curves that the EC50 of the effluent was approximately 3.7% (v/v).

Oxygen Requirements for Growth of Young Coho (Oncorhynchus kisutch) and Sockeye (O. nerka) Salmon at 15 °C

1981 ◽  
Vol 38 (4) ◽  
pp. 399-404 ◽  
Author(s):  
J. R. Brett ◽  
J. M. Blackburn
Keyword(s):  
Growth Rate ◽  
Conversion Efficiency ◽  
Sockeye Salmon ◽  
Critical Level ◽  
Limiting Factor ◽  
Adaptive Mechanism ◽  
Food Conversion ◽  
Lower Oxygen ◽  
Oxygen Requirements ◽  
Food Conversion Efficiency

The growth rate and food conversion efficiency of young coho and sockeye salmon on a full ration were determined in freshwater at oxygen concentrations ranging from 2 to 15 mg/L (15 °C). The data, and a reanalysis of selected published records for bass, carp, and coho, were examined critically in relation to the Limiting Factor hypothesis. It was concluded for all species that above a critical level ranging from 4.0 to 4.5 mg O2/L, growth and conversion efficiency were not limited when tested for relatively short periods (6–8 wk) under the pristine conditions of laboratory tanks. A slight but significant trend to exhibit higher hematocrits at lower oxygen levels revealed the possible presence of an adaptive mechanism for improved respiratory capacity at subcritical oxygen concentrations.Key words: limiting oxygen, growth rate, blood hematocrits, salmon tolerance

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.

Growth Rate of Young Sockeye Salmon, Oncorhynchus nerka, in Relation to Fish Size and Ration Level

1975 ◽  
Vol 32 (11) ◽  
pp. 2103-2110 ◽  
Author(s):  
J. R. Brett ◽  
J. E. Shelbourn
Keyword(s):  
Growth Rate ◽  
Specific Growth Rate ◽  
Sockeye Salmon ◽  
Specific Growth ◽  
Oncorhynchus Nerka ◽  
Limiting Factor ◽  
Fish Size ◽  
Ration Level ◽  
The Family ◽  
Constant Growth

The specific growth rate of young sockeye salmon (Oncorhynchus nerka) was studied for a period of 7 mo to determine the effect of body weight when on restricted and unrestricted rations. It was hypothesized that a restricted ration would result in a fixed growth rate until size became a limiting factor reducing food demand below the prescribed level and thereby reducing growth rate. The results support the hypothesis, with the possible exception that growth rate may increase slightly during the period of fixed ration. On excess ration the specific growth rate fell from 3.6% weight per day (2.4 g mean weight) to 1.0% weight per day (37 g mean weight); intermediate constant growth rates accompanied the periods of fixed ration, inflecting to lower rates subsequently. The general equation log G = a + b log W (where G = specific growth rate, and W = weight in grams) was found to apply to a number of salmonids. The slope value of b = −0.4 ±.04 appears to characterize the family, with the intercept a taking on different values according to the varying capacity for rapid growth.

Corticosteroid Concentrations in Sockeye Salmon (Oncorhynchus nerka) Exposed to Low Concentrations of Copper

1975 ◽  
Vol 32 (4) ◽  
pp. 533-539 ◽  
Author(s):  
Edward M. Donaldson ◽  
Helen M. Dye
Keyword(s):  
Heavy Metals ◽  
Stress Response ◽  
Plasma Cortisol ◽  
Sockeye Salmon ◽  
Oncorhynchus Nerka ◽  
Rapid Evaluation ◽  
Low Concentrations ◽  
Competitive Protein Binding ◽  
Cupric Sulphate ◽  
Sublethal Concentrations

Yearling sockeye salmon (Oncorhynchus nerka) were exposed for 1–24 h to 10−7, 10−6, or 10−5 molar cupric sulphate in freshwater aquaria. Plasma cortisol, cortisone, and "total" corticosteroid concentrations were measured by a competitive protein binding technique.Cortisol, cortisone and "total" corticosteroid levels were significantly higher than control concentrations after 1 h of exposure to 10−5 or 10−6 M copper. "Total" corticosteroid and cortisone concentrations were significantly higher than control concentrations after 2 and 4 h of exposure to 10−7 M copper, respectively. Fish exposed to 10−5 M copper died between 8 and 24 h.The data reflect a rapid corticosteroid stress response to lethal and sublethal concentrations of copper. The technique may be of use for rapid evaluation of effluents containing heavy metals, especially those containing a mixture of toxicants.

Metabolic rates and swimming performance of adult Fraser River sockeye salmon (Oncorhynchus nerka) after a controlled infection with Parvicapsula minibicornis

2005 ◽  
Vol 62 (9) ◽  
pp. 2124-2133 ◽  
Author(s):  
G N Wagner ◽  
S G Hinch ◽  
L J Kuchel ◽  
A Lotto ◽  
S RM Jones ◽  
...  
Keyword(s):  
Sockeye Salmon ◽  
Swimming Performance ◽  
Oncorhynchus Nerka ◽  
Kidney Tissue ◽  
Severe Infection ◽  
Polymerase Chain Reaction Analysis ◽  
Infected Fish ◽  
Fraser River ◽  
Metabolic Rates ◽  
Holding Period

Adult sockeye salmon (Oncorhynchus nerka) acquire infections with the myxosporean kidney parasite Parvicapsula minibicornis during their spawning migration in the Fraser River, British Columbia. Controlled infections with this parasite in wild sockeye salmon had no significant impact on plasma ionic status, metabolic rates, and initial maximum prolonged swimming performance (Ucrit) for fish ranked as either strongly, weakly, or noninfected by polymerase chain reaction analysis of kidney tissue. However, strongly infected fish had significantly lower second Ucrit and recovery ratio (8%) values, indicating decreased ability to recover from exercise. As the present study shows that the severity of infection is affected by time and temperature, the accumulated thermal units (ATU) of exposure in this study were compared with those experienced by naturally migrating sockeye salmon. A parallel telemetry study revealed that early-timed sockeye experienced significantly more ATU (741.4 ± 29.4 °C) than normally migrating salmon (436.0 ± 20.0 °C) prior to spawning because of a significantly longer holding period in the lake system. The present data are discussed in the context of a threshold of >450 °C ATU for severe infection that would first manifest in early-timed fish in the upper reaches of the Fraser River and certainly on the spawning grounds.

Selection indices to improve the efficiency of lean meat production in cattle

1986 ◽  
Vol 42 (2) ◽  
pp. 183-193 ◽  
Author(s):  
G. Simm ◽  
C. Smith ◽  
J. H. D. Prescott
Keyword(s):  
Growth Rate ◽  
Birth Weight ◽  
Conversion Efficiency ◽  
Breeding Value ◽  
Meat Production ◽  
Food Conversion ◽  
Lean Meat ◽  
Selection Indices ◽  
Efficiency Of Selection ◽  
Food Conversion Efficiency

ABSTRACTSelection indices to improve the efficiency of lean meat production in cattle were derived with an aggregate breeding value which comprised growth rate, food conversion efficiency, killing-out proportion and carcass lean proportion. Index measurements were growth rate, food conversion efficiency and ultrasonic fat area. Relative economic values of traits in the aggregate breeding value were calculated for an 18/20-month beef system, assuming a fixed national output of lean meat. Literature estimates of phenotypic and genetic parameters were used. Two indices were derived, one with a complete restriction on genetic changes in birth weight, and the other without restriction. Correlations between the index and the aggregate breeding value were 0·53 for the restricted index, and 0·57 for the unrestricted index. The maximum proportional reduction in expected economic response, due to complete restriction of birth weight was about 0·08. Selection on either index would actually lead to a slight decrease in carcass lean proportion, but this was less than the decrease expected from selection solely on growth rate. Correlations between the indices and the aggregate breeding value (measuring the accuracy of selection) fell by only about 0·01 when ultrasonic measurements were omitted from the index, but fell by about 0·09 when food conversion efficiency was omitted. Sensitivity of the indices to changes in parameters was also examined. With proportional changes of ±0·5 in individual economic weights, or absolute changes of ±0·2 in genetic correlations or −0·2 in heritabilities, the efficiency of selection ranged from 0·93 to 1·00.

The early weaning of pigs V. The inclusion of digestive enzymes and antibiotics in diets for pigs weaned at 6–7 lb. live weight

1959 ◽  
Vol 53 (1) ◽  
pp. 130-135 ◽  
Author(s):  
A. F. C. Calder ◽  
G. A. Lodge ◽  
R. Blair
Keyword(s):  
Growth Rate ◽  
Conversion Efficiency ◽  
Live Weight ◽  
Food Conversion ◽  
Or Efficiency ◽  
Rate Of Growth ◽  
Reduced Rate ◽  
Second Period ◽  
Harmful Effects ◽  
Food Conversion Efficiency

1. Dry-meal diets for pigs weaned at 6–7 lb. mean live weight and 6·9 days mean age were supplemented with antibiotic, pepsin and an α-amylase preparation according to a factorial design involving sixty-four pigs on eight treatments. Antibiotic was included in the respective diets from weaning to 40 lb. live weight and the enzymes from weaning to 25 lb. live weight.2. Antibiotic supplementation gave a 12·5% increase in rate of growth from weaning to 40 lb. P < 0·001) by reducing the incidence of scour and increasing food consumption from weaning to 25 lb. Antibiotic exerted no effect upon efficiency of food conversion.3. Pepsin supplementation increased the incidence of scour and reduced rate of growth by 3·7% whilst being fed (P < 0·1) and by 8·6% after it was omitted at 25 lb. live weight (P < 0·01). Efficiency of food conversion was reduced by 5·5% when pepsin was fed (P < 0·05) and by 4·6% after it was omitted at 25 lb. live weight (P < 0·1).4. α-Amylase appeared to exert little influence upon either growth rate or efficiency of food conversion except in the presence of pepsin. It appeared to counteract the harmful effects of pepsin on growth rate from weaning to 25 lb. and on food conversion efficiency from 25 to 40 lb. This resulted in a 5·5% increase in growth rate during the first period (P < 0·01) and 5·7% improvement in food conversion efficiency during the second period (P < 0·05).5. The overall effects of antibiotic, pepsin and α-amylase supplementation upon time taken to reach 40 lb. live weight were a reduction of 5·6 days, an increase of 3·8 days and a reduction of 3·9 days, respectively.

Effect on pig performance of varying the level of meat meal in cereal grain-meat meal diets

1976 ◽  
Vol 16 (81) ◽  
pp. 478
Author(s):  
VF Fagan ◽  
PR Gillis
Keyword(s):  
Growth Rate ◽  
Conversion Efficiency ◽  
Optimum Level ◽  
Optimum Growth ◽  
Food Conversion ◽  
Lean Meat ◽  
Stage Of Development ◽  
Meat Meal ◽  
Cereal Grain ◽  
Food Conversion Efficiency

A pig feeding experiment was conducted in which six levels of meat meal ranging from 5 per cent to 30 per cent in increments of 5 per cent were fed throughout the experiment. Two additional treatments were included in which an initial meat meal level of 20 per cent was changed to 10 per cent in one treatment (20-10 per cent) and 0 per cent in the other (20-0 per cent) at 54.6 kg liveweight. The optimum level of meat meal was found to vary with the stage of development of the animals. At 30 kg liveweight optimum growth rate and food conversion efficiency occurred at a meat meal level of approximately 21.0 per cent. At 70 kg liveweight optimum growth rate and food conversion efficiency occurred on a diet with approximately 14.5 per cent meat meal. Reducing the level of meat meal at 54.6 kg from 20 per cent to 10 per cent had no adverse effect on any of the attributes measured. However, the reduction from 20 per cent to 0 per cent had a highly significant depressive effect on growth rate, food conversion efficiency and lean meat development. For the treatments fed at constant levels of meat meal, fat cover decreased with increasing meat meal whereas lean meat development increased with increasing meat meal up to 25 per cent but then showed a decline at 30 per cent.

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