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The effect of stocking density on the welfare of farmed rainbow trout - AW1203(1)

The Farm Animal Welfare Council's Report (1996) highlighted the increasing concern over the welfare of farmed fish. In particular, the report emphasised the conplex issue of stocking levels as an area of where research was required to determine optimum densities for farmed trout that were not predjudicial to health and welfare. A pre-requisite of any research proposal must be the ability to develop quantifiable measures of stress. This joint proposal between CEFAS and IOA, Stirling will develop and employ a novel, non-intrustve and non-invasive technique to quantify levels of cortisol, the classic stress hormone, produced by fish and released into water from which it can be measured. This will enable samples to be taken without disturbing or handling the fish. Coupled with more traditional methods such as condition indicies (CI), growth rate, and fin damage, this suite of techniques will allow quantifiable measures of stress and performance to be directly related to stocking densities. The proposal is fully endorsed by the British Trout Association (BTA) who represent over 80% of the UK industry and can guarantee access to a range of farms. In addition, the BTA can act as a vehicle for the rapid dissemination of results or recommendations that will be derived from the project. Overall, this proposal brings together the necessary expertise and access to facilities that can provide a credible answer to the complex issue of determining acceptable maximum stocking densities of trout. The data generated by this project will allow MAFF to provide balanced advice in an increasingly contentious filed and improve the welfare of trout without constraining the development of the industry.
01: Validation and refinement of water-borne cortisone assay.
02: Questionnaire survey
03: Literature review.
04: Small-tank density studies, `testing the technology`
05: `Scaling-up the technology`
06: Effect of environemtnal factors on response to density.
Time-Scale and Cost
From: 2000

To: 2004

Cost: £354,550
Contractor / Funded Organisations
Animal Welfare              
CARD (Committee for Aquaculture R&D)              
Plants and Animals              
Fields of Study
Animal Welfare