Abstract
The incidence of skeletal anomalies could be used as an indicator of the “quality” of rearing conditions as these anomalies are thought to result from the inability of homeostatic mechanisms to compensate for environmentally-induced stress and/or altered genetic factors. Identification of rearing conditions that lower the rate of anomalies can be an important step toward profitable aquaculture as malformed market-size fish have to be discarded, thus reducing fish farmers’ profits. In this study, the occurrence of skeletal anomalies in adult rainbow trout grown under intensive and organic conditions was monitored. As organic aquaculture animal production is in its early stages, organic broodstock is not available in sufficient quantities. Non-organic juveniles could, therefore, be used for on-growing purposes in organic aquaculture production cycle. Thus, the adult fish analysed in this study experienced intensive conditions during juvenile rearing. Significant differences in the pattern of anomalies were detected between organically and intensively-ongrown specimens, although the occurrence of severe, commercially important anomalies, affecting 2–12.5% of individuals, was comparable in the two systems. Thus, organic aquaculture needs to be improved in order to significantly reduce the incidence of severe anomalies in rainbow trout.
Highlights
Aquaculture of fish and other aquatic animals has grown rapidly in the last thirty years [1]
Inappropriate rearing densities were reported in previous studies as causative factors of bone malformations [12] in Atlantic salmon (Salmo salar, L. 1758) fry and parr [29]
No significant correlation was detected between size (TL) and each meristic count, excluding any size effect on the observed meristic counts
Summary
Aquaculture of fish and other aquatic animals has grown rapidly in the last thirty years [1]. Farmed fish are often affected by skeletal anomalies, with the incidence depending on the species, developmental stage, and rearing methodology. Rearing conditions different from the species- or developmental stage-specific ones often cause the onset of skeletal anomalies[12,13,14,15,16,17,18,19,20,21,22]. In several species of commercial interest (i.e. Dicentrarchus labrax, Sparus aurata, Epinephelus marginatus, Dentex dentex, Pagrus pagrus), a reduction in skeletal anomalies (especially commercially relevant ones) has been detected in semi-intensive rearing conditions, characterized by lower densities and larger volumes [11,30,31,32,33,34,35,36]. Malformed market-size fish have to be discarded or sold at lower than market price due to the consumer’s reluctance to buy ‘badlooking’ products
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
