Use of the freshwater rotifer Brachionus angularis as the first food for larvae of the Siamese fighting fish Betta splendens

Larvae of the Siamese fighting fish Betta splendens were reared on the mass-cultured small freshwater rotifer Brachionus angularis Laos strain (UTAC-Lao), Paramecia sp., and Artemia as live food sources. Larvae fed live food were found to have a significantly high survival rate (97.5–100%) 18 days after hatch (DAH) in comparison to the control unfed larvae, which died by 12 DAH. Rotifer-fed larvae were found to grow faster than paramecia-fed larvae. The fastest growth rate was observed in larvae fed a combination of rotifer and Artemia, with growth in these larvae increasing by 282% by 18 DAH [total length (TL) 11.3 ± 1.2 mm] relative to body measurements taken 3 DAH. The next fastest growth rate was observed in rotifer-fed larvae, with a 158% increase in growth observed by 18 DAH (TL 7.6 ± 0.5 mm). The paramecia-fed larvae were found to grow by only 54.3% (TL 4.6 ± 0.1 mm) during the same period.