International Journal of Aquaculture, 2018, Vol.8, No.9, 65-72
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difference in the feed requirement in 15 days was not much and feed was adjusted based on the monthly weight
gain. Mortality of the fish was monitored and recorded every day.
Table 5 Vitamin and mineral composition of the premix (per kg of premix)
Vitamins
Content
Vitamins
Content
Minerals
Content
Vit A
4 000 000 IU
Nicotinic acid
30 000 mg
Iron
25 000 mg
Vit B1
3 000 mg
Pantothenate
10 000 mg
Copper
1 200 mg
Vit B2
4 000 mg
P-amino benzoic
20 000 mg
Manganese
4 000 mg
Vit B6
3 000 mg
Folic acid
1 000 mg
Zinc
6 000 mg
Vit B12
8 000 µg
Biotin
300 000 µg
Iodine
400 mg
Vit C
50 000 mg
Selenium
20 mg
Vit D3
400 000 IU
Cobalt
200 mg
Vit E
40 000 IU
At the end of the experiment, all fish were harvested, counted and length-weight data measured. Based on the data
collected during the experimental period, growth parameters such as mean weight gain per fish, mean daily weight
gain, specific growth rate (SGR), feed conversion ratio (FCR) and survival rate were calculated using the
following formulae as described by Ridha (2006).
Some physic-chemical parameters such as water temperature, dissolved oxygen (DO), pH and conductivity of the
experimental pond water were measured three times a day (morning, noon and in the afternoon) using multi-line
probe (model HQ 40 d Multi meter, HACH Company, USA). To get information on the natural food conditions,
plankton samples were sampled using plankton nets (30 µm for phytoplankton and 50 µm for zooplanktons). Live
samples were identified in the laboratory to the genes level.
4 Statistical Analysis
One-way ANOVA was used to test whether there are any statistically significant differences between the means of
independent groups and Duncan's multiple range test was used to identify which means were significantly
different from one other. Differences were considered significant at
p
<0.05. Data was analyzed using the SPSS
version 18.
Authors’ contributions
The authors wish to thank Ethiopian Institute of Agricultural Research for financing this research. We would like to extend our
gratitude for the assistances from technical assistants and fishermen at National Fishery and Aquatic Life Research Center for the
entire experimental period. All authors read and approved the final manuscript.
Acknowledgements
AD’s contributions were in data analysis, manuscript write up and organized the manuscript according to IJA’s guidelines. AY
contributed in data collection and partly in data analysis.
