Studies on the appearance of skeletal anomalies in red porgy: effect of culture intensiveness, feeding habits and nutritional quality of live preys

Abstract

Despite the great interest of red porgy as a new species for Mediterranean aquaculture, its commercial production is constrained by the high incidence of skeletal deformities occurring in this species under culture conditions. Several studies have been conducted to better understand the origin of these anomalies in this species, using different system intensiveness, rotifers enrichment products or rotifers docosahexaenoic acid content. The first study showed that culture intensification increased the number of fish with an extra vertebrae, what was probably related to the different nutritional quality of live preys employed in each treatment, since water temperature, salinity and genetic background were identical for the different batches of fish studied. Total incidence of skeletal abnormalities was higher in the intensive system, particularly cranial abnormalities and kyphosis in the cephalic vertebrae. In both rearing systems the most common skeletal anomalies were vertebral column disorders, lordosis and fused vertebrae, their localization along the column being affected by the culture intensiveness. Rotifer enrichment, predominantly its docosahexaenoic acid content significantly affected deformities occurrence. A marked positive effect of rotifer docosahexaenoic acid content was found on larval survival. X-ray studies denoted elevated levels of bone abnormalities associated, in both trials, to low docosahexaenoic acid content in live preys. Among different anomalies, the presence of fused vertebrae was the most frequent deformity for both rearing trials. A 50% reduction in the number of deformed fish for each type of deformity was obtained when the larvae were fed higher docosahexaenoic acid levels, denoting the important role of this fatty acid in bone development. Further studies are needed to elucidate the importance of essential fatty acids on the development of bone deformities in fish, since the functions of these fatty acids differ among them and can lead to very different effects in fish metabolism, including bone formation.

Effect of feeding Artemia nauplii enriched with different enhancement products on larval performance of golden pompano Trachinotus ovatus (Linnaeus, 1758)

“…Hamre et al (2002) suggested that the abnormal development of fish larvae may be triggered by insufficient dietary n-3 HUFA in Artemia nauplii. Recent evidence has demonstrated that fatty acids such as DHA, EPA and ARA play important role in bone development and a 50% reduction of deformed fish was observed when fish larvae were fed with higher levels of dietary DHA (Izquierdo et al, 2010). In the present study, incidence of skeletal malformation was lower in the treatment of Algamac 3080 which is consistent with high DHA levels in the feeds.…”

Molecular cloning and expression analysis of the retinoid X receptor (RXR) gene in golden pompano Trachinotus ovatus fed Artemia nauplii with different enrichments

“…Jaw malformations are a common type of skeletal malformation and exhibit in several forms (Cobcroft et al 2001) in both artificial reared and wild caught marine fish (Boglione et al 2001). Izquierdo et al (2010) suggest that PUFA is important in bone formation, and dietary lipids can also affect the fatty acid composition in bone and cartilage (Kokkinos et al 1993;Watkins et al 1997;Liu et al 2004). Hamre et al (2002) suggests that the abnormal development of fish larvae may be triggered by insufficient dietary n-3 HUFA in Artemia nauplii.…”

“…Recent research has demonstrated that fatty acids such as DHA, EPA, and ARA play an important role in bone development. For instance, a 50 % reduction in deformed fish was observed when fish larvae were fed with higher levels of dietary DHA (Izquierdo et al 2010), and alterations in the dietary ARA/EPA ratio can indirectly affect osteoblasts and bone metabolism (Berge et al 2009). In the present study, enrichment significantly affected jaw malformation.…”

“…Although previous studies have demonstrated that feeding with high levels of dietary nutrients (e.g., lipids, fatty acids, vitamins) can improve growth and survival and significantly reduce skeletal malformation (Koven et al 2003;Izquierdo et al 2013), excessive dietary lipids (e.g., DHA, DHA/EPA) and vitamins (e.g., vitamin A, C) can also lead to low survival (Fernández and Gisbert 2011;Hamre et al 2013;Ma and Qin 2014a) and high malformation (Izquierdo et al 2010;Haga et al 2011;Izquierdo et al 2013). Up to present, it is still unclear what the most suitable enrichment formula is for Artemia nauplii enrichment in rearing golden pompano larvae.…”

Malformaciones craneales en larvas y juveniles de peces cultivados

“…Entre las causas a las que se ha asociado la aparición de malformaciones esqueléticas se encuentra la intensificación de los cultivos, condiciones abióticas desfavorables, desbalances nutricionales, enfermedades y factores genéticos (Andrades et al, 1996;Cahu et al, 2003;Fraser & de Nys, 2005;Georgakopoulou et al, 2007;Verhaegen et al, 2007;Izquierdo et al, 2010). El objetivo de la presente revisión bibliográfica, es resumir la información existente sobre las características y las causas de las malformaciones craneales en larvas de peces cultivados.…”