Zhuang Zhimeng

TurbotScophthalmus maximus: stocking density on growth, pigmentation and feed conversion

Juvenile turbot (Scophthalmus maximus) were reared in five different experiment groups in the initial stock densities at 0.28, 0.87, 1.12, 1.16, 2.75 kg/m2 respectively for the study of the density effect on growth, pigmentation and feed coefficient rate. The experiment lasted for 60 days with final stock densities at 1.91, 6.31, 8.86, 11.97, 17.67 kg/m2 respectively. Result showed that, in the same experiment condition, the stocking density has a positive effect on growth in low density and negative in high density. TheSGR (special growth rate) was 3.189, 3.304, 3.447, 3.341, and 3.087 respectively. The uniformity of weight distributing among experiment groups decreased with increasing density. The stocking density had positive effect on feed coefficient rate. Group 1 had the least feed coefficient rate 0.96, and highest at 1.25 in Group 5, the highest density group. High stocking density inhibited the growth and increased the feed coefficient rate. The stocking density had negative relationship to pigmentation improvement for whitened fish.

鳀科(Engraulidae)鱼类DNA 条形码电子芯片研究

本研究将基于线粒体COI部分序列的DNA条形码和DNA芯片技术相结合，以鳀科11属30种鱼类为研究对象，在比对分析其DNA条形码序列的基础上，利用软件Oligo Array 2.1筛选探针，经OligoCalc 优化探针，去除易形成发夹(Hairpin)、茎环(Stem-loop)及自身二聚体结构(Homo- dimers)的探针，再利用Oligo heat map对探针与靶标序列进行虚拟杂交，共有14个物种的24条探针能与靶标序列特异性结合。利用DNA条形码芯片技术能将14个物种鉴定到种，虽然物种识别能力仅占总物种数的46.7%，但鉴定准确率可达100%。因此，基于COI基因的DNA芯片技术对鳀科鱼类物种鉴定有一定的实用价值，但该技术对物种的识别能力尚有较大提升空间，通过筛选和优化得到高质量的分子探针则是突破该项技术的关键。

Comparative analysis of the mitochondrial control region between the cultured and wild populations of Chinese shrimp (Fenneropenaeus chinensis).

In present study,genetic differentiation of the Chinese shrimp Fenneropenaeus chinensis between cultured( 21 individuals) and wild populations( 14 individuals,sequences were downloaded from the GenBank) was investigated using the sequence of mitochondrial control region ( CR ) .Four individuals of the F.merguiensis were chosen as the outgroup during the phylogenetic analysis in this study.Sequences were edited and aligned using DNA Star software and refined manually.Genetic diversity indices such as number of haplotypes,polymorphic sites,transitions,transversions,and indels were obtained using the program ARLEQUIN( Ver.3.0) .Haplotype diversity( h) and nucleotide diversity( л) were calculated with DNASP 4.0.The nucleotide compositions and the average distances between populations and within population were calculated with MEGA 4.0.The Network software was used to draw the minimum spanning tree based on the haplotype data.The results were as follows:the A + T content was higher than the G + C content in both the populations,but the G + C content was a little lower in the cultured population.The results indicated genetic divergence existed between the 2 populations based on the 563 bp sequences.The gene diversity of the wild population( 0.967 2) was a little higher than the cultured population( 0.938 0) .There was no shared haplotype between the 2 populations.The ratio of transitions/transversions of the wild populations and nucleotide diversity were 3.5 and 0.010 6 respectively while they were 4.0 and 0.009 4 for the cultured population.The nucleotide diversity of the wild population was a little higher than cultured population.The K-2P distance was 0.010 8 between the 2 populations,0.010 7 in the wild population and 0.009 5 in the cultured population.Both the NJ phylogenetic tree and the haplotype minimum spanning tree showed no significant genealogical structure.The exact test of population differentiation showed that the 2 populations were significantly different ( P=0.000 9) .The FST value between the populations was 0.069 8( P=0.00) ,which indicated that the difference between 2 populations was significant.This may indicate that some alleles were lost during the aquaculture.

C-banding pattern and nucleolar organizer regions of Cynoglossus semilaevis Gunther, 1873

Abstract The C-banding pattern and nucleolar organizer regions of the metaphase chromosomes of Cynoglossus semilaevis are reported. The interstital regions in all chromosomes including the pair of sex chromosomes had positive C-bands, and the 6th and 12th pairs of chromosomes were entirely stained in most cases. Some chromosomes such as the 1st, 2nd, 7th, 8th, 9th and 10th pairs showed C-bands at centromeric or distal ends. The C-banding heretochromatin occupies 30.03% of the total chromosome surface in C. semilaevis, which is similar to that of amphibians such as Mixophyes fasciolatus(30.2%) and M. schevilli (20.7%), but is rather lower than that of cephalochordate Branchiostoma belcheri (54.3%). Silver staining revealed a single pair of nucleolar organizer regions (NORs) located in the telomeric regions of Chromosome 2. The association of NORs with heterochromatin observed in vertebrates also occurs in C. semi laevis as the telomeric regions of Chromosome 2 are always stained positively with C-banding. ...