Econometric analysis of the factors contributing to the fish price increase in coastal TURFs in Japan: the case of income-pooling fishery for coastal shrimp “Sakuraebi Sergia lucens”

While rights-based management systems have often been encouraged as effective management tools, few studies have analyzed the effects of those systems empirically. In this article, we have focused on a special form of the territorial use rights in fisheries strategy, namely, an income-pooling system, and examined the effects of this system empirically. Earlier studies have regarded the control of fish landing amount and improvement of the quality of fish as the two main determining factors in such a system. Consequently, in our study, we estimated the relationships between these two factors and the price of fish using the econometric method. The results show that the two factors do indeed have significant effects on price changes.     

Inflexibility of vertebral number in chum salmon <Emphasis Type="Italic">Oncorhynchus keta</Emphasis>

Chum salmon Oncorhynchus keta eggs from the Chitose and Shiriuchi rivers in Hokkaido, northern Japan, were incubated under identical conditions with the aim of comparing vertebral number (V _N) to that reported archived data from the 1950s. The comparison revealed that mean V _N of salmon from the Shiriuchi River has remained unchanged for 50 years and is higher than that from the Chitose River. The V _N in the Chitose River salmon was found to be significantly higher than that recorded in the archival data. The variation in the mean V _N of chum salmon fry collected during different seasons and years in the Chitose River falls within a range that has remained constant, suggesting that the difference between the values obtained in our study and the archival data may be due to differences in the timing of egg collection. These results indicate that the mean V _N of chum salmon has been stable for a long period. Incubation experiments under identical conditions are a useful tool for examining changes in genetic structure and detecting the essential properties of populations.     

Panel data analyses to examine effects of subsidies to fishery productions in OECD countries

An econometric analysis, known as a panel data analysis, was conducted to understand the nature and the magnitude of the effect caused by subsidies to fishery productions. Published data on government financial transfers for OECD member countries from 1996 to 2002 were used for this purpose. The result of the panel data analysis indicated that certain financial transfers have brought small but positive influences to economic indicators on fisheries of aggregated OECD countries, while either no or negative effects were recognized in other financial transfers. Different magnitudes of influences were observed according to the types of the transfers. Also, there are cases where two types of financial transfers provide offsetting effects to a single economic indicator. Specifically, the total volume of fishery production for OECD countries is positively influenced by government direct payment programs, but negatively affected by the amount of general services provided by the governments. This study can be regarded as a useful first attempt to examine the empirical link between productions and subsidies of the fishery sectors.     

Variations in the abundance of Pacific saury (Cololabis saira) from the northwestern Pacific in relation to oceanic-climate changes

Effects of oceanic-climate changes on the abundance of Pacific saury (Cololabis saira) in the northwestern Pacific during the last half century were investigated. Abundance indices of both large and medium size groups exhibit interannual–decadal variations, but their patterns were different. The large and medium size groups of saury are corresponding to the recruitments of winter- and spring-cohort, respectively. The abundance of large size group saury was significantly correlated with the winter sea surface temperature (SST) in the Kuroshio region, whereas the medium size group saury showed high correlations with SST in the Kuroshio–Oyashio transition zone and the Oyashio region, indicating that the two size groups are affected by subtropical and subarctic environment, respectively. Significant negative correlation between the abundance index and the southern oscillation index (SOI) suggested that El Niño-southern oscillation (ENSO) events have marked impacts on the large size group saury. Subtropical high pressure index and far east zonal index also show high correlations with the abundance of both large and medium size group saury, indicating a linkage between large-scale atmospheric circulation and the abundance of saury. These correlations demonstrate that the abundance of Pacific saury is directly affected by the SST fields through large-scale atmosphere–ocean interactions from the equatorial Pacific to mid- and high-latitude areas such as El Niño events.     

Convenient Method to Determine Free Fatty Acid of Rice Using Thin‐Layer Chromatography and Flame‐Ionization Detection System

A convenient method which possessed simplicity and high sensitivity was designed to investigate the changes in free fatty acid (FFA) of rice during storage using a thin‐layer chromatography and flame‐ionization detection (TLC/FID) system. In this method, two different solvent systems for TLC were used according to the purpose of experiments. Solvent system A (hexane and diethyl ether and acetic acid 80:20:1) was suitable to obtain a chromatogram showing the overall state of rice lipid degradation. Using solvent system A, the degradation of triglyceride or the increase in FFA during storage was clearly visualized as changes in the chromatogram. Solvent system B (hexane and acetic acid 100:1) was used to improve the low reproducibility of the TLC/FID method. When methyl stearate was used as an internal standard with solvent system B, high reproducibility of the FFA value was obtained, and very small changes were detectable in stored white milled rice. This method has small sample size and simple operation and is more sensitive than the standard titration method. Therefore, this seems to be an especially convenient method for small‐scale storage tests or for experiments using many samples.     

Plasmodium (Bennettinia) juxtanucleare infection in a captive white eared-pheasant (Crossoptilon crossoptilon) at a Japanese zoo

An adult male white eared-pheasant (Crossoptilon crossoptilon) at a Japanese zoo exhibited lethargy and emaciation. Microscopic examination of a blood smear revealed a haemosporidian parasitic infection. Based on the morphological characteristics and molecular analysis of the parasite, it was identified as Plasmodium (Bennettinia) juxtanucleare. This is the first report of P. juxtanucleare infection in bird species belonging to the genus Crossoptilon. Caution against avian malaria infection is required for the conservation of endangered bird species in zoos.     

不同基因型对白菜子叶培养不定芽再生的影响

探讨了基因型对白菜子叶培养不定芽再生的影响。结果表明，不同基因型的不定芽再生率和平均每子叶生芽数差异极大，在被检索的123个大白菜和20个小白菜品种中，芽再生率为0－97.5%，平均每子味生芽数为1.0-10.7个。17个大白菜和5个小白菜品种的不定芽再生率在80％以上。芽再生率与品种起源地、结球类型及熟性无相关。     

Immunological characterization of peripheral blood leukocytes using vaccine for mycoplasmal pneumonia of swine (MPS) in swine line selected for resistance to MPS

This study was conducted to evaluate immunological changes in peripheral blood leukocytes in pigs that were genetically selected for their improved resistance to mycoplasmal pneumonia of swine (MPS), using MPS vaccine as an antigen. Twelve castrated MPS‐selected Landrace pigs were compared with the same number of pigs from a nonselected line by using a time‐course analysis at the hematological level. After the second sensitization with MPS vaccine, the percentages of B cells, CD4⁺ T cells, and natural killer (NK) cells in total leukocytes were lower in the selected line than in the nonselected line, whereas the percentage of granulocytes in total leukocytes increased in the MPS‐selected line. We also assessed the proliferative ability of peripheral blood mononuclear cells (PBMCs) stimulated with Mycoplasma hyopneumoniae, lipopolysaccharide or concanavalin A, and found that although the proliferative ability of the PBMC was not different between the two lines at a steady state, the nonselected line showed a significantly higher proliferative ability after sensitization with MPS vaccine than the selected line regardless of antigens used. These results thus indicate that the selection of pigs on the basis of MPS resistance changes their immunophenotype, and would give us beneficial information for the prevention of MPS infection.     

Variations in nitrogen uptake and nitrate-nitrogen concentration among sorghum groups

Nitrogen uptake and nitrate-N concentration in forage sorghums, which are related to ground water pollution or feed quality under conditions of crop fertilization by only animal wastes, were examined. Seventy-four genotypes of sorghum and Sudan grass were tested. They were classified into 4 groups; grain type and dual purpose type sorghums (6 and 13 genotypes, respectively, Sorghum bicolor Moench), sorgo type sorghum (21, S. bicolor), Sudan type sorghum (22, S. bicolor × S. sudanense (Piper) Stapf), Sudan grass (12, S. sudanense). There was a strong correlation between dry matter (DM) yield and N uptake, with the sorgo type producing the highest DM matter yield and showing the highest N uptake. Nitrate-N, which causes nitrate poisoning of ruminants, was detected mostly in the stem of all the genotypes. The nitrate-N concentration based on DM could be calculated accurately by multiplying the nitrate-N concentration of stem on a fresh matter basis by the DM partitioning ratio of stem divided by the DM concentration of stem. The grain type and the dual purpose type of sorghums with dry stem showed the lowest nitrate-N concentration because these plants had a lower DM partitioning ratio of stem and higher DM concentration of stem. Sudan grass and Sudan type sorghum with the genetic background of Sudan grass showed higher nitrate-N concentrations owing to their ability to accumulate nitrate-N.