Performance of juveniles of Pseudoplatystoma fasciatum fed graded levels of corn gluten meal

Álvaro José De Almeida Bicudo,Ricardo Yuji Sado,José Eurico Possebon Cyrino,Ricardo Borghesi,Jony Koji Dairiki

doi:10.1590/s0100-204x2012000600015

Abstract

The objective of this work was to evaluate corn gluten meal (CGM) as a substitute for fish meal in diets for striped catfish (Pseudoplatystoma fasciatum) juveniles. Eight isonitrogenous (46% crude protein) and isoenergetic (3,450 kcal kg-1 digestible energy) diets, with increasing levels of CGM - 0, 6, 12, 18, 24, 30, 36, and 42% -, were fed to juvenile striped catfish (113.56±5.10 g) for seven weeks. Maximum values for weight gain, specific growth rate, protein efficiency ratio and feed conversion ratio, evaluated by polynomial quadratic regression, were observed with 10.4, 11.4, 15.4 and 15% of CGM inclusion, respectively. Feed intake decreased significantly from 0.8% CGM. Mesenteric fat index and body gross energy decreased linearly with increasing levels of CGM; minimum body protein contents were observed with 34.1% CGM. Yellow pigmentation of fillets significantly increased until 26.5% CGM, and decreased from this point forth. Both plasma glucose and protein concentrations decreased with increased CGM levels. The inclusion of 10-15% CGM promotes optimum of striped catfish juveniles depending on the parameter evaluated. Yellow coloration in fillets produced by CGM diets can have marketing implications.

Highlights

The striped catfish Pseudoplatystoma fasciatum (Linnaeus 1766), a carnivorous, neotropical siluriform fish, is one of the most appreciated Brazilian freshwater fish, both as food and sport fish
Digestible energy concentrations of feed ingredients were calculated from data by Gonçalves & Carneiro (2003) for speckled catfish Pseudoplatystoma corruscans, and by Portz & Cyrino (2004) for largemouth bass Micropterus salmoides
Optimum weight gain was registered for fish fed 10.4% corn gluten meal (CGM) diet, and decreased steadily with increasing dietary CGM (Figure 1)

Summary

Introduction

The striped catfish Pseudoplatystoma fasciatum (Linnaeus 1766), a carnivorous, neotropical siluriform fish, is one of the most appreciated Brazilian freshwater fish, both as food and sport fish. Corn gluten meal (CGM) is a major corn wet milling by‐product, bearing high‐protein contents (minimum 60%), high digestibility (>90%) and high contents of methionine, leucine and glutamic acid (National Research Council, 2011), but it is deficient in lysine, arginine, and tryptophan (Mente et al, 2003). It has strong undesirable odors and flavors because of its high content of unsaturated fatty acids and the bisulfite used during steeping (Park et al, 1997; Cha et al, 2000). The yellow pigmentation of fillets of white‐fleshed fishes reduces their market value (Lovell, 1984), a serious limitation to the use of CGM in neotropical fish diets

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