Thermal conditions during larval pelagic phase influence subsequent somatic growth of Senegalese sole by modulating gene expression and muscle growth dynamics

• Type: Article in International Scientific Journal
• Date: 2013

Authors

Campos, C (Author) Other; Fernandes, JMO (Author) Other; Conceicao, LEC (Author) Other; Engrola, S (Author) Other; Sousa, V (Author) Other; Valente, LMP (Author) ICBAS

Journal

Title: Aquaculture

Vol. 414

Pages: 46-55

ISSN: 0044-8486

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 14 Citations

Scopus - 18 Citations

Scientific classification

FOS: Agrarian Sciences > Agriculture, Forestry, and Fisheries

Other information

Authenticus ID: P-008-D19

DOI: 10.1016/j.aquaculture.2013.07.039

Abstract (EN): In the present study, Senegalese sole eggs incubated at 20 degrees C were reared at three different temperatures (15 degrees C, 18 degrees C or 21 degrees C) during the pelagic phase, and then transferred to a common temperature (20 degrees C) from benthic stage until 100 days post-hatch (dph). Somatic growth, fast muscle cellularity and expression of 15 growth-related genes were compared at the same developmental stage for each temperature (pre-metamorphic larvae, metamorphic larvae, post-metamorphic larvae) and at 83 dph and 100 dph early juveniles. During pre-metamorphosis and metamorphosis, larvae from 21 degrees C weighed significantly more than those reared at 18 degrees C or 15 degrees C (P < 0.001). Relative growth rate (RGR) of pelagic larvae and survival of newly-settled larvae were also higher at 21 degrees C (P < 0.05). Furthermore, an increase in muscle growth towards the highest temperatures was observed concomitantly with an increase in gene expression, namely myogenic regulatory factors (MRFs), myosins, igf-I and fgf6. After transfer to a common temperature (20 degrees C), the 15 degrees C group initiated a process of compensatory growth, inverting relative growth rate values that became the highest, particularly between 83 dph and 100 dph (P < 0.05). This increased growth effort in the 15 degrees C group was accompanied by an upregulation of gene expression in fast muscle, particularly in the 83 dph juveniles. Mrf4 and myHC were upregulated at 15 degrees C and positive correlations with growth were also found for myog or pax7 (P < 0.05). In contrast, mstn1 was down-regulated at 15 degrees C (P < 0.05), suggesting a boost in muscle growth. By 100 dph, the 15 degrees C group had already reached the same weight as the 18 degrees C and the same length as the 21 degrees C ones. At this age, the 18 degrees C juveniles had the largest mean muscle fibre diameter (P < 0.001), and thus fibre hypertrophy seems to be a major growth mechanism relatively to the other groups. Our work shows that temperature during pelagic phase greatly influences the growth trajectory of Senegalese sole juveniles.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10