Please use this identifier to cite or link to this item:
Appears in Collections:Aquaculture Journal Articles
Peer Review Status: Refereed
Title: Body size dimorphism of sea-reared Atlantic salmon (Salmo salar L.): implications for the management of sexual maturation and harvest quality
Authors: Leclercq, Eric
Taylor, John
Hunter, Dougie
Migaud, Herve
Contact Email:
Keywords: Atlantic salmon
sexual maturation
stock management
Issue Date: 23-Mar-2010
Citation: Leclercq E, Taylor J, Hunter D & Migaud H (2010) Body size dimorphism of sea-reared Atlantic salmon (Salmo salar L.): implications for the management of sexual maturation and harvest quality, Aquaculture, 301 (1-4), pp. 47-56.
Abstract: Body size dimorphism between immature and early sexually recruited cohorts of farmed Scottish Atlantic salmon were investigated with the view to optimize the practical management of early maturation over the second-year at sea. Mixed-sex smolts from a single strain and freshwater source were stocked into four discrete commercial sites and sampled at harvest from June to December 2007, 15 to 22 months post-sea transfer. Individuals were sexed and their maturity status determined based on gonado-somatic-index (GSI) and oocyte leading stage. Whole body weight (BW), fork length (FL) and Fulton condition factor (K) were measured and flesh quality analyzed. The immature mixed-sex population and each gender analyzed separately had an isometric weight-length relationship (WLR) but exhibited seasonal variations in K. Body size of immature Atlantic salmon were consistently sexually dimorphic with males exhibiting a higher BW (+13.4%) and FL (+5.9%) but a lower K (-5.0%) than females. Individuals at an early stage of sexual maturation had a significantly higher BW (+35.2%) and K (+20.6%) than the immature cohort in June and July. During this period BW, FL and K together or BW alone were strong and standard indicators of early maturity in our discrete sites. Body size dimorphism described in this study show that sex-ratio is an important parameter of farmed Atlantic salmon populations which is likely to vary following weight-grading and that population composition (sex-ratio and maturation rate) affects the seasonality in K typically observed at harvest. Importantly, the commitment of Atlantic salmon into maturation in spring can be rapidly and accurately estimated in a number of discrete populations by using simple weight-length morphological indicators characterized in a single rearing unit. Following maturation rate estimation, weight-grading implemented according to the predicted stock morphological structure could be used to selectively harvest a high proportion of maturing individuals at a stage where their flesh quality remains optimal. This could be applied as a powerful and practical on-site maturation management tool in the salmon industry as well as in other commercially important fish species.
DOI Link:
Rights: Published in Aquaculture by Elsevier.

Files in This Item:
File Description SizeFormat 
Leclercqetal,2010finalMS.doc883 kBMicrosoft WordUnder Embargo until 31/12/2999     Request a copy
Leclercqetal,2010finalMS[1].pdf639.09 kBAdobe PDFUnder Embargo until 31/12/2999     Request a copy
Leclercqetal2010dimorph.pdf801.08 kBAdobe PDFUnder Embargo until 31/12/2999     Request a copy

Note: If any of the files in this item are currently embargoed, you can request a copy directly from the author by clicking the padlock icon above. However, this facility is dependent on the depositor still being contactable at their original email address.

This item is protected by original copyright

Items in the Repository are protected by copyright, with all rights reserved, unless otherwise indicated.

If you believe that any material held in STORRE infringes copyright, please contact providing details and we will remove the Work from public display in STORRE and investigate your claim.