Techno-Financial Study for Some Sex Reversal Methods of Nile Tilapia Fish | ||||
Egyptian Journal for Aquaculture | ||||
Article 2, Volume 8, Issue 3, September 2018, Page 13-32 PDF (344.32 K) | ||||
Document Type: Original Article | ||||
DOI: 10.21608/eja.2018.31477 | ||||
View on SCiNiTO | ||||
Abstract | ||||
The main aim of this work is a techno-financial evaluation for some sex reversal methods of Nile tilapia. To achieve that study the effect of water temperatures (25, 30 and 35 °C), hormone levels (without (0) and 60 mg 17 ᾳ-MT/ kg feed) and periods of time (1, 2, 3 and 4 weeks) on the male ratio, mortality rate, weight gain of Nile tilapia fries, energy consumption and costs of heating water and hormone were assessed. The obtained results indicated that the male ratio and mortality rate increased with the increasing of water temperature, hormone doses and rearing period. The highest value of weight gain (2.56 g) was obtained at 30 °C water temperature with 60 mg 17 ᾳ-MT/ kg feed after four weeks of rearing. The energy consumption for heating water increased with the increase of water temperature and rearing period. The costs of heating water and hormone increased with increasing water temperature, hormone doses and rearing period. The water temperature of 35°C with 60 mg 17 ᾳ-MT/ kg feed after two weeks gave the best results of male ratio and costs compared to water temperature of 35°C with 0 hormone doses after four weeks. In addition, the water temperature of 35°C with 60 mg 17 ᾳ-MT/ kg feed after one week gave the best results of male ratio and costs compared to water temperature of 35°C with 0 hormone doses after three weeks. | ||||
Keywords | ||||
Nile tilapia; Temperature; Male ratio; sex ratio; weight gain; Specific growth rate; Feed conversion ratio | ||||
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