Higher final weight of fries of Oreochromis aureus
was attained due to feeding on the tested coloured
feeds rather than basal diet. Non-significant changes
were reported for most of growth parameters for fries.
However, they have significant reduction of specific
growth rate (SGR) due to feeding on blue and yellow
feeds. On the other hand, fingerlings fed with basal
diet exhibited a better growth performance than those
fed with different feed colours. Significant reduction in
final weight (Wf), weight gain and average daily
weight gain (ADG) of fingerlings fed brown feed
colour were reported compared to control. Aspartate
aminotranaminase (AST, E.C 2.6.1.1) and alanine
aminotransaminase (ALT, E.C 2.6.1.2) activities were
significantly reduced in fries fed with blue and brown
feeds compared to control. Similarly, alkaline
phosphatase (ALP, E.C.3.1.3.1) activity and albumin
level were significantly reduced in case of fries fed
with brown feed colour. For fingerlings, there were
significant differences found among the experimental
groups, in total protein, albumin, AST, ALT, and
cholesterol. Glutathione (GSH) and water content
were generally reduced in fingerlings fed with the
examined tested coloured feeds. Blue and brown
feed colours induced significant reduction in most of
the tested biochemical parameters from those of the
control. The present study suggests that using
coloured feeds did not promote growth of
Oreochromis aureus, both fries and fingerlings. Also,
adverse biochemical changes for those fed with
coloured feeds were reported. Therefore, ordinary
basal diet is recommended. |