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The Chinese mitten crab, Eriocheir sinensis (H. Milne Edwards), is an important economic and widely cultivated aquaculture species in China. Under the requirements of health aquaculture, effective microorganisms (EM) have been widely introduced in E. sinensis culture. To date, however, we know little about the influence of EM on E. sinensis, especially in aspects of nutritional composition and flavour quality. Aiming to assess the comprehensive effects of EM on E. sinensis, we analysed the growth performance of E. sinensis after each moulting, examined the proximate composition, fatty acids, and flavour nucleotide composition of the edible tissues, as well as muscular amino acid composition in E. sinensis. In this study, we found EM could improve water quality by reducing total nitrogen and total phosphorus contents, while it had a weak promotion on the growth of crab. EM optimized the nutritional composition by improving the total lipid content in edible tissues, increasing beneficial fatty acid (C20:3) level in females and improving the nutritional value of muscular amino acid in males. Still, it caused a sweet taste loss by lowering the content of certain free amino acids especially Ala. However, EM increased umami or sweet taste contributors, that is AMP, GMP and IMP, and decreased off‐flavour contributors, that is Hx and HxR. Thus, the overall flavour quality of edible tissues in female crab was greatly improved by EM. The present study provides us multiple influences of EM on the crab aquaculture, and we recommend supplementing EM into the diet for crab aquaculture in the future. [ABSTRACT FROM AUTHOR]

An 8‐week feeding trial was conducted to determine dietary lysine requirement of juvenile Pseudobagrus ussuriensis (initial body weight: 0.60 g). Six isonitrogenous (crude protein, 400 g/kg) and isolipidic (crude lipid, 50 g/kg) diets were formulated to contain graded levels of dietary lysine (12.8, 19.9, 26.5, 34.0, 40.8 and 44.1 g/kg dry diets, respectively). The results indicated that weight gain, specific growth rate, productive protein value and protein efficiency ratio increased, while feed conversion ratio decreased with increasing dietary lysine level up to 34.0 g/kg dry diet and then levelled off. Fish fed diet with 12.8 g/kg lysine had the lowest lysine content (58.6 g/kg dry matter) in muscle, while fish fed diet with 34.0 g/kg lysine had the highest value (61.6 g/kg dry matter; p <.05). Broken‐line analysis on the basis of weight gain showed that the optimal dietary lysine requirement for maximum growth of juvenile Pseudobagras ussuriensis is 33.5 g/kg dry diet (82.4 g/kg dietary protein). Quadratic regression analysis of protein efficiency ratio against dietary lysine levels indicated that the optimal dietary lysine requirement of juvenile Pseudobagras ussuriensis is 36.4 g/kg dry diet (89.5 g/kg dietary protein). [ABSTRACT FROM AUTHOR]

This study evaluated the effect and phosphorus equivalency value of dietary microbial phytase based on growth performance and nutrient utilization of Channel catfish (Ictalurus punctatus). An all plant‐protein basal diet containing 7.9 g/kg total Phosphorus (P) (Phytate P of 4.5 g/kg) was supplemented with graded levels 0, 300, 500, 1,000, 1,500 and 2,000 U phytase/kg of diet or with 3, 5, 8, 12 g/kg of Ca(H2PO4)2, namely with 0.7, 1.2, 2.0, 3.09 g/kg P as Ca(H2PO4)2. Triplicate groups of Channel catfish (Ictalurus punctatus) juveniles (initial weight, 1.70 ± 0.04 g) were fed the experiment diets for 90 days. The results indicated that dietary phytase supplementation significantly improved growth performance, apparent digestibility coefficient of P and P retention, and decreased feed conversion ratio (FCR), faecal P content and P excretion per gain. Line relation was found between the effects of P and phytase supplementation levels, and the linear response equations of the effects of P and phytase levels were generated and used to calculate the P equivalency values. The average function of P equivalency values (Y, g/kg) of microbial phytase (X, U/kg of diet) was developed: Y = 0.1695 + 0.0021X; R2 = 0.996. The results showed that about 0.38 g of P/kg diet was released by per 100 U of phytase over the range of 300–2,000 U of phytase/kg diet for Channel catfish (Ictalurus punctatus) fed all plant‐protein diet. [ABSTRACT FROM AUTHOR]

A feeding trial was conducted to assess the effects of dietary Schizochytrium meal supplementation on survival, growth performance, activities of digestive enzymes and fatty acid composition in Pacific white shrimp ( Litopenaeus vannamei) larvae (initial body weight 4.21 ± 0.10 mg). Four isonitrogenous and isolipidic diets were formulated to contain graded levels of Schizochytrium meal: 0% (S0, the control diet), 2% (S2), 4% (S4) and 6% dry matter (S6). Results showed that there was no significant difference in survival of shrimps among dietary treatments ( P > 0.05). Shrimps fed diets with 2% and 4% microalgae meal had significantly higher specific growth rate (SGR) than that of shrimps fed diets with 0% and 6% microalgae meal, and no significant differences were observed between shrimps fed diets with 2% and 4% microalgae meal ( P > 0.05). Activity of trypsin in the pancreatic and intestinal segments, and activity of amylase in the pancreatic segments were not significantly affected by dietary microalgae meal levels ( P > 0.05). Specific activities of both alkaline phosphatase and leucine-aminopeptidase in intestine and purified brush border membrane of intestine were significantly higher in shrimps fed diet with 2% microalgae meal ( P < 0.05). There were no significant differences in C18:2n-6, n-3 fatty acids, n-6fatty acids, PUFA and n-3/n-6 in muscle samples among dietary treatments. C16:1n-7, C18:1n-9, MUFA, C18:3n-3 and C20:5n-3 decreased, however, C20:4n-6 increased in the muscle as dietary microalgae meal level increased. In conclusion, 4% Schizochytrium meal in microdiets of shrimps can improve growth performance and may be a valuable additive in the microdiets of shrimps. [ABSTRACT FROM AUTHOR]

An 8-week feeding trial was conducted to evaluate the effects of replacing fish meal with soybean meal ( SBM) on growth, feed utilization, and nitrogen (N) and phosphorus (P) excretion of juvenile Pseudobagrus ussuriensis (initial average weight 0.50 ± 0.00 g). Seven isonitrogenous and isolipidic diets were formulated to contain SBM to replace fish meal protein at 0% (S0), 10% (S10), 20% (S20), 30% (S30), 40% (S40), 50% (S50) and 60% (S60) respectively. To investigate the effects of supplementation with crystalline amino acid to balance diet S60, one diet was formulated to add 0.30% methionine ( SM60). The results showed that there was no significant difference in weight gain among fish fed S0, S10, S20, S30 and S40 diets, however, a significant reduction in this variable occurred when 50% and 60% of fish meal protein was replaced by SBM ( P < 0.05). Apparent digestibility coefficients of dry matter, crude protein and phosphorus of diets were affected by dietary SBM levels. N and P excretion indicate that fish meal replacement by SBM led to an increase in N excretion, but led to a reduction in P excretion. No differences were detected in growth, feed utilization and N and P excretion between fish feed diets S60 and SM60. The results of this study show that 40% of fish meal protein could be replaced by SBM in diets of juvenile P. ussuriensis without having a significant negative effect on growth or feed efficiency, but that higher dietary SBM levels reduce fish performance. [ABSTRACT FROM AUTHOR]

In this paper, we present generic transformations, which allow us to be able to convert any signature scheme satisfying the weak existential unforgeability property into one satisfying the strong existential unforgeability property. Different from the previous researches, we consider this kind of transformations in the bounded leakage model, in which part of the secret information could be learned by the adversary. To achieve such transformations, we define a new cryptographic primitive called leakage resilient chameleon hash function and give an instantiation of it based on leakage resilient hard relation. By making use of this new variant of chameleon hash function, we improve the technique proposed by Steinfeld, Pieprzk, and Wang to obtain a generic transformation that works well in the bounded leakage model. Furthermore, we follow the construction of strong one-time signature by Mohassel to give an instantiation of fully leakage resilient strong one-time signature based on leakage resilient chameleon hash function. We prove that by combining the fully leakage resilient strong one-time signature scheme with the transformation proposed by Huang, Wong, and Zhao, we can obtain another transformation that can convert any fully leakage resilient signature scheme that is weakly existentially unforgeable into one that is strongly existentially unforgeable without changing the signing key. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]