Study on the Morphological Differences of Four Carp Populations

[Objective] The aim was to discuss the morphological differences of four carp populations.[Method] Based on traditional morphological data（including countable and measurable characters） and framework data,the morphological differences and phylogenesis of Yellow River carp population（YR）,wild four-naris carp population（WF）,farmed four-naris carp population（FF） and carp population from Suzhou section of Wusong River（WR） were studied by means of multivariate analysis.[Result] There was no significant difference（P〉0.05） in countable characters among four carp populations.Discriminant analysis showed the discriminating accuracy of YR,WF,FF and WR population were 87.5%,78.1%,73.5% and 96.8% respectively,and the synthetic discriminating accuracy of four populations was up to 83.7%.In addition,cluster analysis revealed that YR population and WF population clustered together,while FF population and WR population clustered together.Principal component analysis indicated that the morphological differences among four populations mainly came from the head,tail and vertical axis of fish.[Conclusion] The study could provide theoretical foundations for the purification and rejuvenation of rare four-naris carp.

夏季食鳖正当时

鳖，又称甲鱼，其体内含有丰富的蛋白质、钙、磷及维生素A．还含有脂肪、糖、烟酸、维生素B1、维生素B2、维生素D以及动物胶、角蛋白、碘等物质．营养价值极高。不论是红烧还是清炖．味道都极鲜美，特别是它背甲周围的柔软表皮部分，通常称为裙边，其口感肥而不腻．是其肉质中味道最为鲜美的部分。

Advances in the Study on Nutrient Requirements of Grouper (Epinephelus sp.): a Review

The paper reviews the recent advances in studying grouper nutrition requirement for the development of cost-effective and environmentally friendly artificial diets. It consists of seven parts: protein and amino acid, lipid and essential fatty acid, carbohydrate, vitamin, mineral, alternative protein source, broodstock and larval nutrition. The review provides some basic information for further investigation of nutrient requirements of groupers.

Do physicochemical variables regulate the distribution of zooplankton communities in reservoirs dominated by filter-feeding carp?

The temporal and spatial distributions of zooplankton communities in the upper, middle, and lower reaches of the Xin＇anjiang Reservoir, Zhejiang, China, were investigated monthly, between 2009 and 2010. Silver carp （Hypophthalmichthys moBtrix） and bighead carp （Aristichthys nobilis） dominated the pelagic fish community of this large, deep reservoir. Cladocerans were distributed evenly throughout the reservoir. Rotifers were mainly found in the upper reaches, while copepods tended to assemble in the lower reaches. The Pearson correlation analysis and stepwise multiple regression were used to identify the major physicochemical gradients influencing community variations. Zooplankton community distributions were influenced by water temperature, dissolved oxygen, phosphorus, nitrogen, and silicon. Excess nutrients, in particular silicon, stimulated rotifer growth. Based on these findings, it is possible to use rotifer density as a bioindicator of eutrophic status in deep reservoir ecosystems.

Effects of small peptides, probiotics, prebiotics, and synbiotics on growth performance, digestive enzymes, and oxidative stress in orange-spotted grouper, Epinephelus coioides, juveniles reared in artificial seawater

Aquaculture production efficiency may increase by using feed additives. This study investigated the effects of different dietary additives [w/w: 2% small peptides, 0.01% probiotics( Bacillus licheniformis) and 0.2% prebiotics(inulin)] on growth performance, digestive enzyme activities, and oxidative stress in juvenile Epinephelus coioides reared in artificial seawater of two salt concentrations(13.5 vs. 28.5). Weight gain rate was significantly higher in fish fed the diet supplemented with small peptides, B. licheniformis, inulin, or synbiotics than that in fish fed the basal diet; the greatest weight gain rate was found in fish fed the small peptide treatment [56.0% higher than basal diet]. Higher feed efficiency was detected in fish fed the diet supplemented with small peptides than that of fish in the other dietary treatments. Total protease activity in the stomach and intestines was highest in fish fed the small peptide-treated diet, whereas lipase activity was highest in those fed synbiotics(combination of Bacillus licheniformis and inulin) than that in fish fed the other treatments. Antioxidant enzyme(total superoxide dismutase and catalase) activities and hepatic malondialdehyde content were higher in fish receiving the dietary supplements and maintained in artificial seawater containing 13.5 salinity compared with those in the control(28.5). Hepatic catalase activity in grouper fed the diets with small peptides or synbiotics decreased significantly compared with that in control fish. Overall, the three types of additives improved growth rate of juvenile grouper and digestive enzymes activities to varying degrees but did not effectively improve antioxidant capacity under low-salinity stress conditions.

Aqua Forestry and Duck Integration in Tamil Nadu, India

A study was taken up on integration of ducks in private and community fish ponds in Tami Nadu. A total of 50 ha of land under private holding and community water bodies each were selected to implement this model. Ducks were integrated based on the water spread area. Fodder, fruit, nuts, fuel, timber trees and vegetables were grown on pond bunds. Control units of fish ponds of farmers holding without integration of ducks also were taken up. A control unit also was established in the university farm land with and without integration of ducks. In private water bodies coconut trees and banana fetched additional revenue. During the first year the average fish production from the private land model was 1,552 kg and 1,731 kg for the first and second year respectively per Hectare. In community ponds the yields were 1,610 and 1,337 kg for the first and second year respectively. In field control units there was no increase in fish yield over the years. In private water bodies the beneficiaries got egg yield of 148 and 90 eggs and community water bodies 144 and 127 eggs per bird were obtained during first and second year resoectivelv.

An Investigation of Elements （Mercury） Status in Marshes in South of Iraq

The study was conducted to investigate the mercury status in three major marshes in southeast Iraq. Sediments, plants （three species） and fish （five species） samples were collected at five locations along the major marshes （AL-Hammar, Cross of AI Fuhod AI Tar, Downstream of AL-Mashab ＆ AL-Salal, Hawizeh and AL-Chebayesh） in southeast Iraq and analysed for mercury concentrations. The sediments were collected at predetermined input and output sources. The mercury concentrations were extremely high in both the sediment and plant samples but variable in fish species. There was a strong relationship between mercury concentrations in the sediments and fishes. Some of the fish species have mercury levels that are considered safe by the international marketing standard/WHO recommendation while others contain mercury levels that may be considered unsafe for human consumption.

Monitoring Trace Metals in Some Cultured Freshwater Fish Species in Saudi Arabia

Three species of freshwater fishes, Oreochromis niloticus, Clarias lazera and Cyprinus carpio, were collected in marketing size from some fish farms in Al-Kharj region, Riyadh area, Saudi Arabia and examined throughout the year 2012 for the following trace metals contents： chromium （Cr）, lead （Pb）, cobalt （Co）, nickel （Ni）, copper （Cu）, zinc （Zn）, iron （Fe） and cadmium （Cd）. The results showed no detection of Cd in all examined species, however, the mean values of other tested metals were within the standard permissible levels except for Pb which showed higher mean levels ranged from 2.05 ± 0.65 mg/kg to 5.30 ± 0.60 mg/kg in O. niloticus, 0.15 ± 0.13 mg/kg to 6.40 ± 0.10 mg/kg in C. lazera and 1.7 ± 0.20 mg/kg in C. carpio compared to the maximum permissible limits recorded by Saudi Arabia Standards Organization （SASO） for fish and shellfish. Consequently, from the public health point of view, efficient routine examination of cultured fishes to control trace metals during culture processes and before marketing is recommended.

Distribution and Relationships of Seven Trace Elements （Cr, Fe, Mn, Ni, Co, Cu and Zn） in Freshwater Fish from Five French Fishing Areas

The concentrations of seven essential trace elements in 149 freshwater fish from eight fish species （European eel, bream, common carp, European catfish, roach, perch, pike and pikeperch） from five different French fishing areas from contaminated and control sites were measured by inductively coupled plasma mass spectrometry after microwave digestion under pressure. Differences in the concentration of elements in the muscles of these species were examined and the mean levels were compared for each species with previous French and European studies. The condition factor and the differences between the control and contaminated sites and between predatory and non-predatory groups, with respect to the concentration of these elements, were also studied.

Otolith chemical signatures of spottedtail goby Synechogobius ommaturus in coastal waters of China

This study explores the potential existence of local stocks of Synechogobius ommaturus using otolith chemical signatures. The concentrations of 10 elements （K, Ca, Na, Mg, St, Pb, Ba, Mn, Co, Zn） in the otoliths from eight stocks （Dandong, Dalian, Tianjin, Dongying, Weihai, Qingdao, Ganyu and Xiamen） ofS. ommaturus were measured by Inductively Coupled Plasma Mass Spectrometry and regressed against otolith weight. No significant correlation between otolith weight and concentrations of Na, Mg, Ca, Sr, Co, Ba, Zn and Pb were observed. Concentrations of K and Mn were correlated with otolith weight. Consequently, the residuals of the regressions were used instead of the original concentrations in subsequent analyses. Analysis of variance （ANOVA） showed no significant difference between males and females in otolith chemical signatures. Differences were found among the locations for K, Sr, Mn, Co, Ba, Pb, but not for Ca, Na, Mg and Zn. Residuals of the regressions of elemental concentrations against otolith weight that fitted the normal distribution and homogeneity were studied by discriminant analysis. The success of the discriminant function to predict the location of S. ommaturus capture ranged from 100% for Weihai and Xiamen stocks, to only 44.4% and 62.5% for Qingdao and Dandong stocks, respectively. The average prediction success was 80.3%.

Prolate and Oblate Shape Coexistence in ^188Pt

A standard in-beam y-spectroscopy experiment for ^188Pt is performed via the ^176yb（^18O, 6n） reaction at beam energies of 88 and 95 MeV, and the level scheme for ^188Pt is established. Prolate and oblate shape coexistence has been demonstrated to occur in ^188Pt by applying the projected shell model. The rotation Mignment of i13/2 neutrons drives the yrast sequence changing suddenly from prolate to oblate shape at angular momentum 1Oh, indicating likely a new type of shape phase transition along the yrast fine in ^188Pt.

Response properties of the electrosensory neurons in hindbrain of the white sturgeon,Acipenser transmontanus

Objective The passive electrosense is a primitive sensory modality in the Chondrostei, which include sturgeon and paddlefish. Using electroreceptors, these fish detect the weak electric fields from other animals or geoelectric sources, and use this information for prey detection or other behaviors. The primary afferent fibers innervating the electroreceptors project to a single hindbrain target called the dorsal octavolateral nucleus （DON）, where the electrosensory information is first processed. Here, we investigated the electrophysiological properties of DON neurons. Methods Extracellular recording was used to investigate the response properties of DON neurons to dipole electric fields with different amplitudes and frequencies in the white sturgeon, Acipenser transmontanus. Results The DON neurons showed regular spontaneous activity and could be classified into two types： neurons with a low spontaneous rate （〈10 Hz） and those with a high spon- taneous rate （〉10 Hz）. In response to sinusoidal electric field stimuli, DON neurons showed sinusoidally-modulated and phase-locked firing. In addition, neurons showed opposite phase responses corresponding to the different directions of the dipole. Conclusion The response properties of DON neurons match the electrosensory biological function in sturgeon, as they match the characteristics of the electric fields of its prey.

开弓没有回头箭

前不久的一天下午,在淮安市三堡乡新庄村,农民陈加强向村委会补交了550元鱼塘承包金,并在承包合同书上愉快地签上了自己的姓名。办完手续后,陈加强一手拿着合同书,一手紧握住乡法律服务所主任张正祥同志的手说:“我上午胡搅蛮缠,实在是自己不懂法。” 就在这天上午,新庄村委会按事前招标承包通告规定。