Testduckweed .Lemnas pp as a potential food for grass carp Ctenopharhyngodonidell and common carp Cyprinuscarpio L

Abstract

This study was conducted to record the growth of the grass carp (Ctenopharhyngodonidell) and common carp (Cyprinuscarpio) when they fed exclusively either the duckweed (Lemna spp.) what happen when they raised together and fed on these plants. 30 fish of common carp in average weight 25 ± 5 g and 30 fish of grass carp 23 ± 5 g was distributed randomly on 6 glass tanks, (40×60×30) they were represent 3 treatments for each species as follows: common carp fed on duckweed only, grass carp fed duckweed only, mixed species fed on duckweed. The results were as follows: The grass carp fed on duckweed have higher food conversion efficiency, conversion rate and protein efficiency ratio. The common carp fed on duckweed have higher food conversion efficiency and food conversion rate and protein efficiency ratio. Survival rate was it reached 100% in the treatment of mixed common carp and grass carp while the lowest survival rate was recorded in the treatment of common carp. Results indicated that mixed species treatment which fed on duckweed were significantly higher in the final weight, daily weight gain, specific growth rate, relative growth rate, food conversion efficiency, feed conversion rate, protein efficiency ratio. Conclusion this results was summarized the mixed culture deals to increasing in weight gain with increasing of food. duckweed could be used as acimpeleted food within this trial