A high incidence of jaw malformation has hindered the production of quality striped trumpeter Latris lineata
juveniles and has been correlated with walling behaviour in Artemia-fed larvae. In this study, striped trumpeter
were reared from first feeding to 29 days post-hatching (dph) in different coloured tanks (black or
white), culture conditions (clear or greenwater) and fed different diets (enriched or non-enriched rotifers
and Artemia), to examine behaviour, retinoid receptor gene expression and jaw malformation. The highest
incidence and severity of jaw malformations occurred in clearwater and enriched diet treatments and were
significantly more common in white (70±15%, mean±SD) than in black tanks (26±15%). In black tanks,
jaw malformation was significantly more common in larvae fed enriched diets (18±14%) than in those fed
non-enriched diets (8±8%) and in clearwater (19±14%) versus greenwater (7±6%). At the end of the
rotifer feeding phase, larvae were significantly larger in black than white tanks, and longer in greenwater
than in clearwater. In the Artemia feeding phase, larval growth was slowest and mortality was highest in
non-enriched diet treatments. Larval length and survival were higher in black tanks and in enriched diet
treatments, whilst survival was almost twice as high in greenwater (46±18%) than clearwater (26±13%).
The average proportion of larvae walling over the duration of the experiment was higher in white than
black tanks, and higher in enriched than non-enriched treatments, with lowest walling in greenwater.
There was no consistent relationship between feed intake and jaw malformation. However, there was a
significant positive correlation between walling and the incidence of jaw malformation at 29 dph in larvae fed
enriched diets. The expression pattern of three retinoid receptor genes indicated that live feed enrichment and
stress could potentially perturb retinoic acid-associated pathways leading to skeletal abnormality. We found
that the use of greenwater, black tanks and enriched live feeds is required for good growth, development,
survival and final yield of striped trumpeter. The study emphasises the importance of reducing walling in
the culture of oceanic larvae and may have direct application in the rearing of other marine fish with similar
malformations.