Recovery of opercular anomalies in gilthead sea bream, Sparus aurata L.: morphological and morphometric analysis

Abstract

Opercular anomalies are very frequent in reared gilthead sea bream and these can negatively influence the product value. Field observations have suggested that opercular malformations can recover over time. In order to verify this hypothesis, 140-day-old gilthead sea bream with monolateral opercular anomalies were divided into three groups, according to the type and increasing seriousness of the opercular malformations, and another group was composed of fish with bilateral opercular anomalies. All groups were monitored for 16 months. In the group with monolateral anomalies, the opercular recovery process was documented by morphological (stereomicroscope) and morphometric analysis. For the latter analysis, two relevant areas, A and T, were identified in the cephalic region. The ratio (T - A)/T, tending to 1, represents the recovery index (RI) of anatomical integrity and quantifies the recovery level of opercular complex anomalies. Results suggested that the recovery process was considerable over the 16 months of investigation but should not be considered complete. At the end of the study, 61% of the gilthead sea bream population with monolateral opercular defects recovered external integrity, whereas the population with bilateral defects showed a poorer recovery capability.

Skeletal anomaly assessment in diploid and triploid juvenile Atlantic salmon (Salmo salar L.) and the effect of temperature in freshwater

“…). Nevertheless, exposure of gills due to lack or damage of opercular plate may affect respiration and marketability of the product (Beraldo & Canavese ). In the present study, the prevalence was high in comparison to previous studies (as reported below) and the cause(s) was not determined.…”

Skeletal anomalies in reared European fish larvae and juveniles. Part 2: main typologies, occurrences and causative factors

“…Among them, anomalies of the gill cover have been recorded to affect mainly gilthead seabream (up to 80%: Koumoundouros ; a maximum of 9%: Cataudella et al . ; 5–20%: Beraldo & Canavese ), but also European seabass and a variety of candidate species, in some lots (Paperna ; Barahona‐Fernandes ; Francescon et al . ; Verhaegen et al .…”

Concurrence of lower jaw skeletal anomalies in triploid Atlantic salmon (Salmo salar L.) and the effect on growth in freshwater

“…). The anomaly may expose fish to diseases and impact biological functions, and as a consequence performance, and product saleability (Beraldo & Canavese ; Boglione et al . ; Bruno, Noguera & Poppe ).…”