Growth, Condition Factor, and Bioenergetics Modeling Link Warmer Stream Temperatures Below a Small Dam to Reduced Performance of Juvenile Steelhead

2010 ◽  
Vol 84 (4) ◽  
pp. 369-377 ◽  
Author(s):  
Sally T. Sauter ◽  
Patrick J. Connolly
Keyword(s):  
Growth Condition ◽  
Condition Factor ◽  
Bioenergetics Modeling

Relative Contributions of Dietary and Waterborne Copper to Tissue Copper Burdens and Waterborne-Copper Tolerance in Rainbow Trout (Oncorhynchus mykiss)

1993 ◽  
Vol 50 (8) ◽  
pp. 1683-1689 ◽  
Author(s):  
P. A. Miller ◽  
R. P. Lanno ◽  
M. E. McMaster ◽  
D. G. Dixon
Keyword(s):  
Rainbow Trout ◽  
Oncorhynchus Mykiss ◽  
Growth Condition ◽  
Condition Factor ◽  
Copper Tolerance ◽  
Food Conversion ◽  
Rainbow Trout Oncorhynchus Mykiss ◽  
Lethal Level ◽  
Cu Tolerance ◽  
Food Conversion Efficiency

In a 42-d study, rainbow trout (Oncorhynchus mykiss) were fed a diet containing either 13 or 684 mg Cu∙kg−1 and simultaneously exposed to waterborne-Cu concentrations of 5, 32, 55, or 106 μg∙L−1 (low-Cu diet) or 13, 38, 62, or 127 μg∙L−1 (high-Cu diet). There were no significant effects on mortality, growth, condition factor, or food conversion efficiency. Elevated dietary Cu increased Cu concentrations in liver (p < 0.001), kidney (p < 0.001), gill (p = 0.005), and digesta (p < 0.001). Increasing waterborne-Cu concentrations elevated Cu concentrations in liver (p = 0.018) and kidney (p = 0.002) but not in gill (p = 0.930) or digesta (p = 0.519). Waterborne-Cu exposure increased Zn concentrations in liver (p = 0.025) but decreased those in kidney (p = 0.045). For fish on the high-Cu diet, diet provided 99, 85, and 63% of the Cu in the liver for the 38, 62, and 127 μg∙L−1 waterborne-Cu treatments, respectively. Based on Cu tolerance (incipient lethal level for Cu), dietary and waterborne Cu partitioned into functionally different compartments. Although both waterborne-Cu (p < 0.00001) and dietary-Cu (p = 0.019) preexposure increased Cu tolerance, waterborne Cu had a much greater impact.

Reduced growth, condition factor and body energy levels in Atlantic salmon Salmo salar L. during their first spring in the sea

2010 ◽  
Vol 42 (2) ◽  
pp. 248-259 ◽  
Author(s):  
Henriette Alne ◽  
Maike Oehme ◽  
Magny Thomassen ◽  
Bendik Terjesen ◽  
Kjell-Arne Rørvik
Keyword(s):  
Atlantic Salmon ◽  
Growth Condition ◽  
Salmo Salar ◽  
Condition Factor ◽  
Energy Levels ◽  
Atlantic Salmon Salmo Salar ◽  
Body Energy

scholarly journals Analysis of some biological aspects of the Blue-spotted tilapia, Oreochromis leucostictus (Trewavas, 1933) in Lake Naivasha, Kenya

2020 ◽  
Author(s):  
Cishahayo Laurent ◽  
Edwine Yongo ◽  
Edna Waithaka ◽  
Eunice Mutethya
Keyword(s):  
Sex Ratio ◽  
Growth Condition ◽  
Condition Factor ◽  
Lake Naivasha ◽  
Weight Relationship ◽  
Total Length ◽  
Fish Samples ◽  
Commercially Important ◽  
Biological Aspects ◽  
The Mean

Oreochromis leucostictus is one of the commercially important tilapiine in Lake Naivasha. Its stock in the lake has declined due to the effect of fishing and pollution. This study investigated on its length-weight relationship, condition factor, sex ratio and maturity. Fish samples (233) were caught using gillnets of mesh-sizes 2-5 inches. Each individual fish was measured (cm) and weighed (g) in the field. The specimens were preserved in ice and transported to the laboratory for analysis of maturity. The mean (±SE) total length and weight for all fish was 21.3±0.3 cm TL and 187.4±8.3 g, respectively. Males 22.3±0.4 cm were significantly larger than females 19.2±0.5 cm. The mean condition factor was 1.06, 0.99 and 1.04 for male, female and combined sexes, respectively. The overall population sex ratio was 2.19:1.0 (male: female) that deviated significantly from 1:1. The slope b of the length-weight relationship was 1.92, 3.07, 2.33 for males, females, and combined sexes, respectively. Length at 50% maturity was estimated at 21.0 cm for females and 26.0 cm for males. Ripe oocytes and testis were found in all fish sizes. Comparisons with earlier studies suggest that the parameters of its growth, condition and maturity vary greatly from the different habitats.

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