Effect of different photo periods on growth performance, survival rate and skin colour of Nile tilapia fingerlings

الملخص EN

Nile tilapia (O.

niloticus) fingerlings averaging 15.2 g in weight were reared under four photoperiod regimes (24L : 0D, 18L : 6D, 12L : 12D as control and 6L : 18D) for 90 days to investigate their growth performance, survival rate, skin colour and proximate body composition using eight fiberglass tanks with capacity of 240L water.

Fish were fed a commercial diet containing 26.58 % protein .Different growth measurements of tilapia were recorded every 15 days intervals.

The physico-chemical analysis of water was recorded daily.

The body composition and skin colour of the whole fish were determined at the stocking and at the end of the experiment.

Results showed that growth performance for tilapia was significantly (P ≤ 0.05) increased with increasing photoperiod.

No mortality occurred in any of the experimental groups.

Also, the photoperiod of 24L : 0D showed the best food conversion ratio, Skin luminosity L * and body protein and lipid content.

The findings revealed that photoperiod 24L : 0D was more suitable for optimum growth performance, survival rate and skin colour of Nile tilapia fingerlings than any other photoperiods.