Skeletal anomalies in reared Senegalese sole Solea senegalensis juveniles: a radiographic approach

Abstract

Reared Senegalese sole Solea senegalensis Kaup show a high incidence of vertebral anomalies; however, little is known about its skeletal anomaly profile in the later farming phases. The purpose of this study was to provide a detailed description and quantification of the most common skeletal anomalies in reared Senegalese sole in the juvenile stage by means of computed radiography. A total of 374 Senegalese sole were classified according to the external morphology of the fish as normal or altered and then radiographed in latero-lateral and in dorso-ventral projections. Radiographic evaluation of anomalies focused especially on vertebral body anomalies (VBA) and vertebral column deviations (VCD). The 2 orthogonal projections provided a more complete visualization of the skeleton. Approximately 75% of the individuals showed at least 1 anomaly, while VBA and/or VCD were detected in 48.9% of the specimens. Regarding external morphology, 88% of the fish were categorized as normal, although about 72% of these normal fish displayed abnormalities in radiographies. The most frequent anomalies consisted of deformations of the caudal complex plates (hypurals, parhypural and epural), preurals and caudal vertebrae. Scoliosis was the most prevalent among VCD, affecting the caudal area in almost 15% of the individuals. The anomaly profile at the juvenile stages showed some differences compared to what has been reported previously in earlier stages of development. In light of these results, further investigation into the progression of skeletal anomalies over time and the causative factors at later stages is required.

Skeletal Anomalies in Senegalese Sole (Solea senegalensis, Kaup) Fed with Different Commercial Enriched Artemia: A Study in Postlarvae and Juveniles

“…In this sense, the presence of a thin layer of bony tissue in some deformed structures at both stages could indicate bone formation, helping to strengthen the concave side of the spines or plates. These altered elements might be undergoing remodeling and modeling processes and perhaps afterward acquire a non-deformed shape, leading to the attenuation of the incidence of spine deformities at later stages [ 51 ]. Moreover, EB, EC, and ED diets presented a higher frequency of individuals with VBA and/or VCD at 105 dah than the respective groups at 31 dah.…”

Skeletal Anomalies in Senegalese Sole (Solea senegalensis), an Anosteocytic Boned Flatfish Species

“…Fish were euthanized with an overdose of Tricaine methanesulfonate (MS-222; Sigma-Aldrich, Darmstadt, Germany) and fixed in 10% buffered formalin. Computed radiography was performed in fixed fish placed in 2 orthogonal projections according to previous reports 7,32 and using methacrylate plates to position the fish. Radiographic images were evaluated with a software program (RadiAnt DICOM Viewer 1.9.16.7446 Medixant, Poznań, Poland) to detect skeletal deformities.…”

“…Detection of malformations is primarily done by gross examination and palpation of the fish in Senegalese sole farms 38 and, to a lesser extent, by refined techniques such as double-staining technique, 8,19,21 computed radiography, 7,32 and even computed tomography, 31 as in other fish species. 11,24,42…”

Simple morphometrics for predicting lordosis-induced deviations of body-shape in reared Gilthead seabream (Sparus aurataL.)

“…2013), and the categorization of skeletal abnormalities on the basis of their effects on fish morphology at harvest (Loy et al . 1999, de Azevedo et al . 2017, Fragkoulis et al .…”