Effects of stocking density on growth performance, biochemical indices, water quality and economic benefits of giant freshwater prawn Macrobrachium rosenbergii in a greenhouse
NI Meng1, CHEN Xuefeng1, GAO Qiang1, CHENG Haihua1, HUA Jianquan2, RONG Huanan2, ZHOU Zhiming1, YUAN Julin1*
1. Key Laboratory of Healthy Freshwater Aquaculture, Ministry of Agriculture and Rural Affairs， Zhejiang Institute of Freshwater Fisheries, Huzhou 313001, China; 2.Cixi Fisheries Technology Extension Center, Cixi 315300, China
Abstract: To probe into the effects of different stocking densities on the water quality, growth and blood biochemical indices of giant freshwater prawn Macrobrachiumrosenbergii “Taihu No 2” and evaluate the optimal stocking density, giant freshwater prawn with an initial body mass of (0.61±0.05)g were randomly reared in nine 2 000 m2 plastic ponds in a greenhouse at three stocking densities: low density (LSD， 37.5 ind./m2), middle density (MSD, 45.0 ind./m2) and high density (HSD, 60.0 ind./m2) with triplication for 60 days. It was found that there were significantly higher ammonia nitrogen and nitrite nitrogen levels in HSD group than those in LSD and MSD groups at the end of the experiment (P<0.05). There were significantly lower survival rate, final body mass, final body length, length of carapace and specific growth rate in HSD group than those in LSD and MSD groups (P<0.05). However, food conversion ratio was found to be significantly higher in HSD group than those in LSD and MSD groups (P<0.05), without significant difference between LSD group and MSD group(P>0.05). The yield was shown to be increased with the increase in stocking density, significantly higher in MSD and HSD groups than that in LSD group (P<0.05), and the maximal output and profit were observed in MSD group. The giant freshwater prawn in HSD group had significantly higher blood glucose level and alanine transaminase activity than those in LSD and MSD groups did(P<0.05), with significantly lower total protein and globulin levels in HSD group than those in LSD and MSD groups (P<0.05). The findings indicated that stocking density of 45.0 ind./m2 was of the appropriate giant freshwater prawn culture in the greenhouse.
2021, Vol. 36 
