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Relationships between measures of oxidative stress and adaptive antioxidant defenses were studied in red sea bream (Pagrus major, RSB) caged at eight locations along the Fujian coast, China. Oxidative damage in tissues was investigated by measuring concentrations of protein carbonyl (CP) and reactive oxygen species (ROS), lipid peroxidation (LPO), acetyl cholinesterase activity (AChE), concentration of thiol groups and activities of enzymes associated with antioxidant defense. Magnitudes of antioxidant defense parameters were significantly, positively correlated with oxidative stress. Significantly greater ROS, LPO and CP content was observed in most tissues of RSB caged at three locations relative to those at the other locations. RSB caged at one location, Meizhou, exhibited significantly more DNA damage than did RSB caged at other locations. AChE activities in liver, kidney and muscle were statistically different among locations. Multivariate analyses were used to categorize the environmental quality of different locations. The battery of measures of oxidative stress proved to be a useful integrator of oxidative stresses that could be compared among locations. [Copyright &y& Elsevier]

Two trials were conducted to determine the optimal replacement level of rice bran meal (RBM) as a substitute for kelp meal (KM) in the diet of the hybrid abalone Haliotis discus hannai ♀ × H. fulgens ♂. This study also investigated whether betaine as an attractant supplementation could be used to facilitate RBM as a replacement for KM. In Trial 1, RBM was used to replace 25%, 50%, and 100% of the dietary KM (RBM25, RBM50, and RBM100, respectively) based on a diet containing 30% KM (Con). In Trial 2, RBM50 was the same as in Trial 1, and betaine was supplemented in RBM50 at 0.2% (B1), 0.4% (B2), and 0.8% (B3) in the diets. Abalone (weight approximately 4 g) were randomly assigned to four groups replicated in triplicate (60 abalone/replicate). The abalone were fed the experimental diets for 10 weeks. In Trial 1, compared to the Con group, no significant differences were observed in final weight (FW), final shell length (FSL), specific growth rate (SGR), or daily increment in shell length (DISL) at 25% KM replacement by RBM. However, 50% KM replacement significantly reduced the FW, FSL, SGR, and DISL compared to the Con group. There were no significant differences in the proximate composition of the soft body tissues of the abalone. In Trial 2, growth performance parameters of the hybrid abalone were significantly improved with increasing levels of betaine in the diets compared to those fed diet RBM50, reaching the maximum value in the B2 group. Consistent with the feed intake results, the hormone concentrations of neuropeptide Y (NPY) and orexins in the digestive gland and cerebral ganglia of abalone were significantly increased when the supplementation level of betaine in the diets was increased to 0.2%. However, no apparent impacts were observed on NPY or orexin concentrations among the B1, B2, and B3 groups. Finally, we suggest 0.4% betaine supplementation along with replacing 50% of the KM with RBM in the hybrid abalone diet. The optimal diet is a cost-effective alternative feed formulation that can reduce the dependence on KM for abalone production in China. This study also demonstrates the potential of betaine as a feed attractant in abalone aquaculture. • 25% kelp meal (KM) can be replaced by rice bran meal (RBM) without obvious adverse impacts on the growth performance of the hybrid abalone. • The addition of 0.4% betaine in diets increased the replacement level of KM by RBM to 50% without negatively affecting the growth performance of the hybrid abalone. • Development of such diets will significantly reduce feed cost and reliance on KM for abalone feed company in China. [ABSTRACT FROM AUTHOR]

Aim: Genetic data were used to measure the phylogeographic distribution of the limpet, Cellana toreuma along the China coast in order to acsertain impacts of historic events, ocean currents and especially freshwater discharge from the Yangtze River on the connectivity of intertidal species with limited larval dispersal capability., Methodology/principal Findings: Genetic variation in 15 populations of C. toreuma (n = 418), ranging from the Yellow Sea (YS), East China Sea (ECS) and South China Sea (SCS), were determined from partial mitochondrial cytochrome c oxidase subunit I gene. Genetic diversity and divergence based on haplotype frequencies were analyzed using CONTRIB, and AMOVA was used to examine genetic population structure. Historic demographic expansions were evaluated from both neutrality tests and mismatch distribution tests. Among the 30 haplotypes identified, a dominant haplotype No. 1 (H1) existed in all the populations, and a relatively abundant private haplotype (H2) in YS. Pairwise F(ST) values between YS and the other two groups were relatively high and the percentage of variation among groups was 10.9%., Conclusions: The high nucleotide and gene diversity in the YS, with large pairwise genetic distances and relatively high percentages of variation among groups, suggests that this group was relatively isolated from ECS and SCS. This is likely driven by historic events, ocean currents, and demographic expansion. We propose that freshwater discharge from the Yangtze River, which may act as physical barrier limiting the southward dispersal of larvae from northern populations, is especially important in determining the separation of the YS group from the rest of the Chinese populations of C. toreuma.