Evaluation of
corn gluten meal as a protein source in diets for gilthead sea bream (Sparus
aurata L.) juveniles
T.G. Pereira, A. Oliva-Teles-2003
Aquaculture Research, 34(13):
1111-1117
Abstract:
A 12-week growth trial was conducted to
evaluate corn gluten meal as an alternative protein source to fish meal in
diets for gilthead sea bream juveniles. The experimental diets were
formulated to be isonitrogenous and isoenergetic and to have 20%, 40%, 60%
and 80% of fish meal protein, the only protein source in the control diet,
replaced by corn gluten meal.
At the end of the growth trial only the
group fed the diet with 80% corn gluten protein exhibited significantly
reduced growth and feed efficiency compared with the fish meal-based diet.
This was most likely due to a dietary amino acid deficiency in that diet. A
trend was noticed for feed efficiency to improve with the replacement of
fish meal protein in the diets up to 60%. There were no significant
differences among groups in protein and energy retention (as percentage of
intake).
At the end of the trial whole body water
content of the experimental groups was significantly lower and the lipid
content of groups including 60% and 80% corn gluten protein was
significantly higher than that in the control. No other differences were
observed in whole body composition among groups.
Apparent digestibility coefficients (ADC)
of the diets were evaluated in a separate trial. The ADC of dry matter of
the experimental diets was significantly higher than in the control diet;
there were no significant differences among diets in the ADC of energy and
protein, except for the ADC of protein of diet with 80% corn gluten protein,
which was significantly lower than the control.
The results of this study indicate that
corn gluten meal can replace up to 60% fish meal protein in diets for
gilthead sea bream juveniles with no negative effects on fish performance.
(Faculdade de Ciências do Porto e CIIMAR,
Pr. Gomes Teixeira, 4099-002 Porto, Portugal. E-mail of A. Oliva-Teles: aoteles@fc.up.pt)