University Of Tasmania

File(s) not publicly available

Effects of enzyme supplementation to dehulled lupin-based diets on growth, feed efficiency, nutrient digestibility and carcass composition of rainbow trout, Oncorhynchus mykiss (Walbaum)

journal contribution
posted on 2023-05-16, 20:33 authored by Farhangi, M, Christopher CarterChristopher Carter
High inclusion levels of dehulled lupin (Lupinus angustifolius) in salmonid diets significantly decrease growth rates. This may be caused by the high concentrations of non-starch polysaccharides including oligosaccharide (OS) in lupin. The antinutritive effects of OS have not yet been fully investigated in fish. The objective of this study was to determine the effect of enzyme supplementation of dehulled lupin-based diets on the fish performance. There were two control diets: a fish meal-based diet with no plant protein (FM) and a diet that contained 50% dehulled lupin (L). Four experimental diets based on diet L and containing four different exogenous enzyme supplements were used: diet L(E) (Energex™); diet L(B) (Bio-Feed™ Pro); diet L(α) (Alpha galactosidase™); and diet L(Mix), which contained all the enzymes. Fish were randomly stocked into tanks in duplicate groups of 38 fish, 16.58±0.169 (SE) g, and were fed twice a day for 6 weeks. The supplemented enzymes did not improve weight gain in fish fed lupin-based diets. However, mixed enzyme significantly improved Protein Efficiency Ratio (PER). Apparent digestibility of DM, CP and GE significantly improved in fish-fed L(E) diet. None of the supplemented enzymes affected digestive tract indices or carcass composition. Surprisingly, weight gain was significantly higher in fish-fed L(α), L(E) and L(Mix) diets as compared with FM diet. Feed intake was significantly higher in fish-fed L, L(α) and L(E) diets compared with the FM diet. It is concluded that storing of lupin kernel under a suitable condition may have partially hidden the positive effects of exogenous enzymes through activating the endogenous enzymes. © 2007 Blackwell Publishing Ltd.


Publication title

Aquaculture Research










Institute for Marine and Antarctic Studies


Blackwell Publishing Ltd

Place of publication

United Kingdom

Repository Status

  • Restricted

Socio-economic Objectives

Fisheries - aquaculture not elsewhere classified

Usage metrics

    University Of Tasmania