Biology and culture of the clown loachChromobotia macracanthus(Cypriniformes, Cobitidae) : 3- Ontogeny, ecological and aquacultural implications

Autor: Laurent Pouyaud, Marc Legendre, Darti Satyani, Agus Priyadi, Jacques Slembrouck, Etienne Baras
Přispěvatelé: Institut des Sciences de l'Evolution de Montpellier (UMR ISEM), École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UR226, Balai Penelitian dan Pe ngembangan Budidaya Ikan Hias (BP2BIH), AMAFRAD, Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Institut de recherche pour le développement [IRD] : UR226-Centre National de la Recherche Scientifique (CNRS)
Rok vydání: 2012
Předmět:
Zdroj: Aquatic Living Resources
Aquatic Living Resources, EDP Sciences, 2012, 25 (2), pp.119-130. ⟨10.1051/alr/2012011⟩
Aquatic Living Resources, 2012, 25 (2), pp.119-130. ⟨10.1051/alr/2012011⟩
ISSN: 1765-2952
0990-7440
DOI: 10.1051/alr/2012011
Popis: International audience; Hatchlings of clown loach (3.8 mm in total length, TL) are pelagic. When reared at 26-28 degrees C, they become benthic 3 days after hatching (dah), when their swim bladder is inflated. The fin development sequence (pectorals < caudal < dorsal = anal < pelvic) is typical of the clade Ostariophysi. All fins and finrays are fully elongated at 20 mm TL, but the finfold persists until 25-26 mm TL (start of juvenile stage). Melanophores appear at 3 dah, they form a 5-bar pattern at 5 dah, then two bars (III and V) vanish progressively, producing at 26 mm TL the 3-bar pattern that is typical of adults. Throughout the ontogeny, the pigment pattern exhibits a structural regularity (bars spaced at regular intervals), which is interpreted in a functional perspective by reference to the maintaining of crypsis and signalling throughout. Exogenous feeding commences at 4 dah (5.5 mm TL). Food intake (FI) increases rapidly, from 6% wet body mass (WM) at 5.5 mm TL to >20% WM in fish >7 mm TL. Gut evacuation rate (R-g) increases with increasing meal size and fish size, as a result of gut coiling (from 8 to 15 mm TL), and is highest at 11 mm TL (about 10% WM h(-1) in fish feeding maximally). The allometric increase of FI and R-g during the early larval stages is accompanied by increasing capacities for growth, so early sizes differences amplify rapidly during the ontogeny. Nevertheless, growth remains slow (mean of 0.4 mm TL day(-1) from 4 to 29 dah; 0.9 mm TL day(-1) for top growers). By contrast, unfed fish display long resistance to starvation (until 14-15 dah). The combination of slow growth and long resistance to starvation is discussed in respect to the reproductive phenology of the species, as the capacity of making metabolic economies prevails over fast growth for seasonal strategists spawning mainly at the start of the rainy season.
Databáze: OpenAIRE
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