Use of a natural aquatic fern, Azolla microphylla, as a main component in food for the omnivorous-phytoplanktonophagous tilapia, Oreochromis niloticus L.

Abstract

An aquatic fern, Azolla microphylla (strain 175 MI, Catholic University of Louvain, Belgium), a natural source of protein, was used in this study to produce low-cost feeds for the omnivorous-phytoplanktonophagous tilapia, Oreochromis niloticus L. Fish were grown in a recirculating system and fed with six different diets in triplicate groups. Diets were formulated with approximately similar total protein, ranging from 27.25 to 27.52% dry weight (dw), gross energy content ranging from 85.1 to 96.5 MJ kg )1 dw, and with different levels of dry meal Azolla (0, 15, 20 30 40, 45% diet dw). All diet levels with incorporated Azolla meal exhibited weight gain, thus it can be assumed that Azolla in good combination with local products can be used to promote fish culture development. The Azolla-free diet and the diet containing 15% Azolla produced the same growth performance. However, the least expensive diet containing 45% Azolla also exhibited growth and can be used as a complementary diet for tilapia raised in fertilized ponds.

Digestibility of dry matter and nutrients from three ingredients by the carps, Labeo fimbriatus (Bloch, 1795) and Cyprinus carpio Linnaeus, 1758 with a note on digestive enzyme activity

“…According to Datta (2011), azolla can be incorporated up to 25% in the diet of L. rohita. Diet containing 15% azolla performed comparable to the control when fed to O. niloticus (Fiogbe et al, 2004). The reduction in growth recorded in rohu fry fed higher levels of azolla protein concentrate was attributed to the imbalance in amino acid make-up of azolla protein.…”

Effets d’une couverture d’<i>Azolla</i> sur les performances de croissance et de production de <i>Clarias gariepinus</i> (Burchell) élevé en étangs

“…Cette fougère est en effet riche en protéines: 15-35% de la matière sèche (Détimmerman et Petry, 1988), présente un bon profil en acides aminés (Sanginga et Van Hove, 1989;Leonard, 1997) et est appétée à l'état frais ou séché par les poissons omnivores et phytophages (Liu, 1988). Elle est de ce fait incorporée dans leur ration alimentaire, avec des résultats satisfaisants avec Oreochromis niloticus L. (Fiogbé et al, 2004 ;Abou et al, 2007aAbou et al, , 2007b. Elle est directement mise en culture sur une partie de la superficie des étangs piscicoles, ce qui la rend disponible en permanence aux poissons.…”

Biomass production of Azolla microphylla as biofilter in a recirculating aquaculture system

“…Many reports on Azolla had been published, but almost of them were related to its function as natural feed resouces. Azolla was recommended by FAO (2009) as feed in small-scale aquaculture and had been used as a main component in food for Tilapia (Fiogbé et al 2014). According to Lumpkin and Placknett (1980) and Van Hove (1989), Azolla under good conditions presents high productivity and protein content (generally 20-30%, on a dw basis).…”