Vertebral deformities in wild and farmed European plaice (Pleuronectes platessa)
Aquaculture, vol.612, 2026 (SCI-Expanded, Scopus)
- Publication Type: Article / Article
- Volume: 612
- Publication Date: 2026
- Doi Number: 10.1016/j.aquaculture.2025.743278
- Journal Name: Aquaculture
- Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Artic & Antarctic Regions, BIOSIS, Geobase
- Keywords: Deformity, Flatfish, Morphology, Plaice, Vertebra, Wild fish
- Akdeniz University Affiliated: Yes
Abstract
European plaice (Pleuronectes platessa) has been suggested as a new species for aquaculture in Norway, but an initial study on plaice up to ∼50 g indicated that vertebral deformities are problematic. The main aim of the present study was therefore to create a baseline for vertebral deformity occurrence and severity (radiology) in wild European plaice. Wild plaice (0.4–4.0 kg) from 5 different locations in Western Norway (Sognefjorden, Masfjorden, Austevoll, Hardangerfjorden, Boknafjorden) were compared with a population of farmed plaice (0.6–1.5 kg). Total vertebrae counts were not statistically different between the wild populations (range 42 to 44 vertebrae, mean 43.3) and tended to be lower in the farmed fish (range 41 to 43 vertebrae, mean 42.7). Vertebral deformity frequencies were not statistically different between the wild populations (range13–38 %), while the farmed plaice were significantly elevated (71 %). The vertebral deformities in farmed plaice were severe; average number of deformed vertebrae among deformed fish was 16.5 in farmed plaice and ranged between 2.0 and 8.0 among the wild populations. In farmed plaice, deformities mostly covered the abdominal (V4–13) and caudal (V14–41) regions of the vertebral column, and there were negative correlations between the number of deformed vertebrae, and both body length and shape (length/width ratio). Farmed plaice had a lower body length/width ratio than wild plaice irrespective of vertebral deformities. The present results show that the deformity level of wild plaice is similar to what has been reported in other wild marine fish in Western Norway. The study further reveals that farmed plaice have a different body shape than wild plaice and confirms that vertebral deformities must be considered as a welfare concern in farmed European plaice.