| Abstract | An experiment was conducted for a period of 84 days to
determine the appropriate feeding regimes for Nile tilapia
(Oreochromis nilotlcus) and effect of different feeding regimes on
water quality in intensive culture system. Complete diet was given
to the fish with 5 feeding schedules in relation to diel water
quality fluctuation in green water tanks where treatment 1 was that
fish were fed once a day at 6 am, treatment 2, fish were fed once
a day at 9 am, treatment 3, fish were fed once a day at 6 pm,
treatment 4, fish were fed twice a day at 9 am and 1 pm, and
treatment 5, fish were fed 4 times a day at 9 am, 11 am, 1 pm and
3 pm. The feeding performances, fish growth and water quality were
determined throughout the experiment.
The total feed intakes in treatments 1, 2, 3, 4 and 5 was
2,439.9 g, 3046.9 g, 2477.2 g, 3023.0 g and 3201.4 g respectively.
The overall relative feed intakes (%BW/day) for those treatments
were 1.91%, 2.32%, 2.05%, 2.39% and 2.54%,with corresponding food
conversion ratio of 0.90, 0.98, 0.94, 1 .21 and 1 .39, respectively.
Final fish size in each treatment was 238.4 g, 264.5 g, 232.8 g,
241.4 g and 239.4 g with the daily weight gain (g/fish/day) of
2.21, 2.59, 2 . 20, 2.28 and 2.23, respectively. There were no
significant differences in the overall feeding performances and
fish growth among those 5 feeding regimes.
In different feeding regimes throughout the experimental
period, the maximum and minimum dissolved oxygen concentration in
tanks ranged from 0.3 mg/L to 11.6 mg/L while afternoon DO ranged
from 2.2 mg/L to 16.7 mg/L. Temperature in the afternoon ranged
from 30.4 to 34.5 C and total ammonia concentration ranged from
non- detectable to 0.42 mg/L. There were no significant difference
in terms of water quality parameters among the various feeding
regimes |
