Estimation of jundiá (Rhamdia quelen) dietary amino acid requirements based on muscle amino acid composition

Abstract

Jundiá, Rhamdia quelen (Quoy & Gaimard, 1824), is a catfish native to Central and South America. The species has a number of excellent farming features, such as easy handling, low temperature resistance, efficient feed conversion, flavorsome meat and absence of intramuscular bones, and has been increasingly raised in Southern Brazil. However, most of its nutritional requirements have not yet been determined, including the essential amino acid (EAA) requirements. The objective of the present study was to estimate such requirements through the determination of muscle tissue amino acid composition for four groups of jundiá. Two groups were wild caught and allocated in two categories: from 1 to 100 g and from 101 to 200 g. The other two groups, obtained from artificial propagation, were differentiated by the diet they had been fed for three months preceding sampling (one diet containing 38% crude protein, CP, and 3,200 kcal kg-1 estimated metabolizable energy, ME, and other with 34% CP and 3,650 kcal kg-1 ME). Similar amino acid compositions were obtained for all groups. An estimate of jundiá daily EAA requirements was made using jundiá muscle tissue composition and also taking into account the average EAA requirement for other omnivorous species such as channel catfish (Ictalurus punctatus, Rafinesque, 1818), Nile tilapia (Oreochromis niloticus, Linnaeus, 1758) and common carp (Cyprinus carpio, Linnaeus, 1758) . The estimated requirements proposed could help formulating diets for jundiá until dietary EAA dose-response experiments are performed.