Larval rearing of the Asian
Catfish, Pangasius bocourti (Siluroidei, Pangasiidae): alternative
feeds and weaning time
Le Thanh Hung, Nguyen Anh Tuan, P. Cacot, J.
Lazard-2002
Aquaculture, 212(1-4): 115-127
Abstract:
Three experiments were carried out to evaluate Pangasius
bocourti larval rearing with different feeding regimes. In the first
experiment, survival rates of larvae fed on Artemia nauplii,
cladocereans (Moina sp.), or red-blood worms (Tubifex) were
not significantly different, 91-93%. However, Artemia nauplii and
Tubifex gave similar growth rates (35-36% day-1) while Moina
sp. resulted in lower growth. Commercial trout-starter feed resulted in the
lowest survival (67%) and growth rates (20% day-1) when compared
to live feed.
In the second experiment, feeding dry feed based on
yeast and beef liver or feeding decapsulated Artemia cysts improved
survival rates. These were 90% and 87%, respectively, not significantly
different from Artemia nauplii. Regarding growth, dry feed and
decapsulated Artemia cysts resulted in lower growth rates than Artemia
nauplii. These were 23% and 29%, respectively. Stomach content analysis
showed that reduced growth in decapsulated-cyst fed larvae compared to live Artemia
reflected a difference in feed ingestion and preference rather than a
difference in nutritional quality of the feed.
In the third experiment, it was shown that larvae
require 3-day feeding on Artemia nauplii before weaning them on to
trout-starter feed to prevent negative effects on growth. Three days after
initial feeding, fish stomach attains its biological and physiological
functions.
(Centre
de Coopération Internationale en Recherche Agronomique pour le Développement,
Département Elevage et Médecine Vétérinaire/Groupe Aquaculture
Continentale Méditerranéenne et Tropicale (CIRAD-EMVT/GAMET), TA 30/01,
34398 Montpellier cedex 5, France, e-mail of J. Lazard : lazard@cirad.fr)