Stocking density practices of commercial UK rainbow trout farms

Aquaculture ◽  
2006 ◽  
Vol 259 (1-4) ◽  
pp. 260-267 ◽  
Author(s):  
B.P. North ◽  
T. Ellis ◽  
J.F. Turnbull ◽  
J. Davis ◽  
N.R. Bromage
Keyword(s):  
Rainbow Trout ◽  
Stocking Density ◽  
Trout Farms

scholarly journals Factors Affecting Fin Damage of Farmed Rainbow Trout

2015 ◽  
Vol 38 (1) ◽  
pp. 61-71 ◽  
Author(s):  
Aleksandar Cvetkovikj ◽  
Miroslav Radeski ◽  
Dijana Blazhekovikj-Dimovska ◽  
Vasil Kostov ◽  
Vangjel Stevanovski
Keyword(s):  
Regression Analysis ◽  
Rainbow Trout ◽  
Water Temperature ◽  
Production Systems ◽  
Stocking Density ◽  
Fish Welfare ◽  
Factors Affecting ◽  
Pectoral Fins ◽  
Main Factors ◽  
Trout Farms

Abstract The aims of this study were to determine the influence of the factors affecting fin damage under different rainbow trout production systems and to compare the findings with the known experimental reports. The study was based on a questionnaire that included information about the main factors i.e. oxygen level in exit water, water temperature, stocking density, daily feed ration, number of meals and grading frequency on seven rainbow trout farms. Standard multiple regression analysis, based on a previously published fin damage dataset, was used to assess the relationship between the level of fin damage per fin and the factors. Daily feed ration received the strongest weight in the model for the caudal, anal and both pectoral fins, whereas number of meals received the strongest weight in the model for both pelvic fins. Grading frequency received the strongest weight only in the dorsal fin model. Lower levels of daily feed ration and number of meals combined with higher water temperature increased the level of fin damage, whereas stocking density had no effect. The results conform to the experimental research on fin damage in rainbow trout. The research model contributes to the overall assessment of fish welfare and the regression analysis used in this study could be used on rainbow trout farms to evaluate the effect of the main factors on the level of fin damage.

Articles: Characteristics of Effluent and Sludge from Two Commercial Rainbow Trout Farms in Minnesota

1997 ◽  
Vol 59 (2) ◽  
pp. 161-172 ◽  
Author(s):  
R. P. Axler ◽  
C. Tikkanen ◽  
J. Henneck ◽  
J. Schuldt ◽  
M. E. McDonald
Keyword(s):  
Rainbow Trout ◽  
Trout Farms

The relationships between stocking density and welfare in farmed rainbow trout

2002 ◽  
Vol 61 (3) ◽  
pp. 493-531 ◽  
Author(s):  
T. Ellis ◽  
B. North ◽  
A. P. Scott ◽  
N.R. Bromage ◽  
M. Porter ◽  
...  
Keyword(s):  
Rainbow Trout ◽  
Stocking Density

Feed efficiency of Rainbow trout (Onchorynchus mykiss) kept at high and low stocking density

2017 ◽  
Vol 13 (0) ◽  
pp. 11
Author(s):  
W. M. Rauw ◽  
A. M. Larran ◽  
L. A. Garcia-Cortes ◽  
M. L. Rodriguez ◽  
J. Fernandez ◽  
...  
Keyword(s):  
Rainbow Trout ◽  
Feed Efficiency ◽  
Stocking Density

scholarly journals Study of pathogenicity and severity of Lactococcus garvieae isolated from rainbow trout (Oncorhynchus mykiss) farms in Kohkilooieh and Boyerahmad province

2019 ◽  
Vol 22 (1) ◽  
Author(s):  
Esmaeil Karami ◽  
Mojtaba Alishahi ◽  
Taravat Molayemraftar ◽  
Masoud Ghorbanpour ◽  
Mohammad Reza Tabandeh ◽  
...  
Keyword(s):  
Rainbow Trout ◽  
Systemic Infection ◽  
Fish Farms ◽  
Pcr Assay ◽  
Biochemical Tests ◽  
High Severity ◽  
Lactococcus Garvieae ◽  
Specific Pcr ◽  
Rainbow Trout Oncorhynchus Mykiss ◽  
Trout Farms

Abstract Background Lactococcus garvieae is one of the most important risk factors in the rainbow trout culture. Therefore, the purpose of this study was to identify and detect strains isolated from rainbow trout suspected of having Lactococcus garvieae using biochemical characteristics and PCR and determination of the degree of severity of isolated strains. Methods In this study, the cause of lactococcosis in selected rainbow trout farms in Kohkilooieh and Boyerahmad province was assayed. Gram-positive and catalase-negative bacterial isolates were first obtained from selected trout fish farms using conventional biochemical tests and PCR assay. The 10-day LD50 method (concentration causing 50% mortality in 10 days) was used to determine the severity of the isolated bacteria. Results One bacterial isolate was detected from all sampled fish which confirmed as Lactococcus garvieae using a specific PCR assay based on the 16S rDNA gene by producing a single band of 1107 bp. Analysis of the rate of mortality showed that the 10-day LD50 was 4.6 × 105 CFU/fish. The results of this study showed that isolated bacteria had high severity for rainbow trout. The presence of bacteria in internal organs of suspected fish showed a severe systemic infection in challenged fish. Antibiogram assay also indicated that the isolated Lactococcus garvieae were resistant to some mostly used antibiotics in rainbow trout. Conclusions According to current research, it can be concluded that the condition of lactococcosis in the studied area is not suitable, and despite the presence of disease, there is no proper action to control and prevent the disease. Unfortunately, isolated bacteria from the studied area have a very high severity compared to bacteria isolated from other regions of the country or other countries. Therefore, further investigation is needed to determine the cause of this difference and possibly in the design of the vaccine.

scholarly journals Moderate stocking density does not influence the behavioural and physiological responses of rainbow trout ( Oncorhynchus mykiss ) in organic aquaculture

2020 ◽  
Vol 51 (7) ◽  
pp. 3007-3016 ◽  
Author(s):  
Pierluigi Carbonara ◽  
Sébastien Alfonso ◽  
Francesco Gai ◽  
Laura Gasco ◽  
Giovanni Palmegiano ◽  
...  
Keyword(s):  
Rainbow Trout ◽  
Oncorhynchus Mykiss ◽  
Physiological Responses ◽  
Stocking Density ◽  
Rainbow Trout Oncorhynchus Mykiss ◽  
Organic Aquaculture

Effects of stocking density on the growth and flesh quality of rainbow trout (Oncorhynchus mykiss) reared in a low-tech aquaponic system

Aquaculture ◽  
2020 ◽  
Vol 529 ◽  
pp. 735653
Author(s):  
Marco Birolo ◽  
Francesco Bordignon ◽  
Angela Trocino ◽  
Luca Fasolato ◽  
Antón Pascual ◽  
...  
Keyword(s):  
Rainbow Trout ◽  
Oncorhynchus Mykiss ◽  
Stocking Density ◽  
Flesh Quality ◽  
Rainbow Trout Oncorhynchus Mykiss

scholarly journals The synergistic interaction of thermal stress coupled with overstocking strongly modulates the transcriptomic activity and immune capacity of rainbow trout (Oncorhynchus mykiss)

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Alexander Rebl ◽  
Tomáš Korytář ◽  
Andreas Borchel ◽  
Ralf Bochert ◽  
Joanna Ewa Strzelczyk ◽  
...  
Keyword(s):  
Rainbow Trout ◽  
High Temperature ◽  
Critical Temperature ◽  
Differentially Expressed Genes ◽  
Reference Group ◽  
Synergistic Effects ◽  
Stocking Density ◽  
Transcript Abundance ◽  
Condition Index ◽  
Differentially Expressed

Abstract The objective of the present study is to identify and evaluate informative indicators for the welfare of rainbow trout exposed to (A) a water temperature of 27 °C and (B) a stocking density of 100 kg/m3 combined with a temperature of 27 °C. The spleen-somatic and condition index, haematocrit and the concentrations of haemoglobin, plasma cortisol and glucose revealed non-significant differences between the two stress groups and the reference group 8 days after the onset of the experiments. The transcript abundance of almost 1,500 genes was modulated at least twofold in in the spleen of rainbow trout exposed to a critical temperature alone or a critical temperature combined with crowding as compared to the reference fish. The number of differentially expressed genes was four times higher in trout that were simultaneously challenged with high temperature and crowding, compared to trout challenged with high temperature alone. Based on these sets of differentially expressed genes, we identified unique and common tissue- and stress type-specific pathways. Furthermore, our subsequent immunologic analyses revealed reduced bactericidal and inflammatory activity and a significantly altered blood-cell composition in challenged versus non-challenged rainbow trout. Altogether, our data demonstrate that heat and overstocking exert synergistic effects on the rainbow trout’s physiology, especially on the immune system.

Sign in / Sign up

Export Citation Format

Share Document