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A feeding experiment was undertaken for 84 days to investigate the growth performance and the feed utilization of two horseshoe crab species from partial replacement of fish meal (FM) with blood meal (BM), meat and bone meal (MBM), and poultry by-product meal (PBM) in their diet. Triplicate groups of Tachypleus tridentatus or Carcinoscorpius rotundicauda were fed nine isonitrogenous (digestible protein 40%) and isoenergetic (digestible energy 14 MJ kg-1) diet treatments. For both species, the growth performance, that is, final individual body weight and thermal-unit growth coefficient (TGC), and feed utilization, that is, including feeding rate (FR) and feeding efficiency ratio, of the juveniles fed with PBM and MBM at 2:1 ratio were higher than those of juveniles fed with diets containing PBM and MBM at 1:1 ratio at the same FM replacement level. Final individual body weight, TGC, and FR of the two species fed with the 100% FM replacement diets were significantly lower than in other diet treatme...

The green-lipped mussel Perna viridis is distributed widely in estuarine and coastal areas of the Indo-Pacific region and is regarded as a cultured mussel or by-product in aquaculture. However, in estuarine and coastal waters where salinity varies with freshwater input and rainfall during the wet season, hypoxia frequently occurs, especially when waters are highly eutrophic. The current study aimed to evaluate the effects of two key environmental factors in estuarine and coastal waters—dissolved oxygen (DO) and salinity—on growth and body composition of juvenile green-lipped mussels P. viridis. Parameters studied included shell length (SL), tissue dry weight (TDW), condition index (CI), specific growth rate (shell length, SGR L ; tissue dry weight, SGR W ), moisture content (MC), crude protein (CP), crude fat (CF), crude carbohydrate (CC), crude ash (CA), and energy content (EC). Mussels were cultured for 6 wk at 4 salinities (15, 20, 25, and 30) and 3 dissolved oxygen concentrations (1.5 ± 0.3, ...

Preoperative treatments, such as starvation, lead to an improvement in receptiveness of nucleus insertion and reduction in the postoperative stress responses of oysters. And the nacre-secreting mantle graft (saibo) solution can maintain the balance of osmotic pressure inside and outside cells and ensures normal cellular activities after operation, which is also a key aspect of pearl culture. In this study, the combined effects of gonadal elimination (caused of starvation) and saibo preservative solution on the physiological responses and energy budget of the pearl oyster Pinctada martensii were investigated. The results showed that the absorption efficiency, clearance rate, respiration rate, oxygen-to-nitrogen ratio, and scope for growth, except excretion rate, were significantly decreased under complete gonad elimination treatment. No significant effects under saibo preservative solution and between the two stressors were observed for physiological indices. Moreover, the subsequent pearl production results showed that complete gonadal elimination negatively influenced pearl performance. The present study demonstrated that partial gonadal elimination treatment was more beneficial to pearl production than complete gonadal elimination.