Effects of Stocking Density on the Individual Growth and Differentiation of the Oriental River Prawn Macrobrachium Nipponense (De Haan, 1849) (Caridea: Palaemonidae). Issue 6 (1st November 2016)

• Record Type: Journal Article
• Authors: Sun, Shengming; Fu, Hongtuo; Gu, Zhimin; Zhu, Jian
• Is Part Of: Journal of crustacean biology. Volume 36:Issue 6(2016)
• Page Start: 769
• Page End: 775
• Publication Date: 2016-11-01
• Subjects: antioxidant enzyme activities -- aquaculture -- China; Crustacea -- Periodicals; Crustacés -- Périodiques; Crustacea; Periodicals; 595.305
• DOI: 10.1163/1937240X-00002482
• Languages: English
• ISSNs: 0278-0372

Abstract

Abstract: We evaluated the effect of stocking density on the concentrations of oxy-hemocyanin and lactate in hemolymph, the antioxidant ability of the hepatopancreas, and the biochemical composition in large and small individuals of the prawn Macrobrachium nipponense (de Haan, 1849 ) cultured in a cage system. Juveniles $(0.24\;{\rm{g}}\;{\rm{initial\;weight}})$ were stocked in 15 cages with stocking densities of 40, 80, 120, 160, and ${\rm{200}}\;{\rm{individuals/}}{{\rm{m}}^2}$ for 8 weeks. The results demonstrated that final mean weight, weight gain, gross feed conversion ratio, and survival rate were significantly lower in stocking densities of 160 and ${\rm{200}}\;{\rm{individuals/}}{{\rm{m}}^2}$ $(P \lt 0.05)$ than in other treatment groups, not through water quality deterioration or food competition, but through the role of density as an environmental stress factor. The coefficient of variation (CV) of body weight increased as the stocking density increased, and the CV in the 160 and ${\rm{200}}\;{\rm{individuals/}}{{\rm{m}}^2}$ groups were over $70\% $ . The values of hemolymph oxy-hemocyanin and lactate concentration, superoxide dismutase (SOD), catalase (CAT) activities, malondialdehyde (MDA) content, and heat-shock protein 70 (HSP70) mRNA expressions of hepatopancreas in small individuals were significantly higher than those of the large ones in high stocking densities of 160 and ${\rm{200}}\;{\rm{individuals/}}{{\rm{m}}^2}$ . This study provides evidence that crowding stress can stimulate the physiological response of the small individuals raising their oxy-hemocyanin and lactate level in the hemolymph and decreasing antioxidant ability on hepatopancreas, which ultimately lead to suppress growth performance of the small individuals.