Evaluation of a microplate agglutination test (MAT) for serological diagnosis of canine brucellosis

A microplate agglutination test (MAT) was compared with the tube agglutinin test (TAT), a standard test for the diagnosis of Brucella canis, in terms of the sensitivity and specificity. The results showed that MAT was more sensitive, simpler to perform and easier to read the results than TAT. On top of that the MAT allows us to handle a larger number of samples at once. Using this method we conducted sero-surveillance of the prevalence of B. canis in dogs kept in an Animal Shelter located in Kanagawa Prefecture. Twelve of 485 (2.5%) showed seropositive against B. canis. These results indicate that B. canis infection in dogs is still occurring in Japan.     

A dog with acute myelomonocytic leukemia

A three-year-old dog with marked leukocytosis, lymphadenopathy, and diarrhea showed an increase in unidentified blasts in the peripheral blood, and they were proliferated in the bone marrow. The dog was diagnosed with myelomonocytic leukemia (M4) because the blast cells were demonstrated by cytochemical staining to be both myeloid and monocytic cells. Although the dog was treated with a multi-combination chemotherapy and induction therapy using vitamin K2, it died on day 47 after the first admission. This case is the first report of M4 in Japan.     

Characterization of canine platelet activation induced by platelet activating factor (PAF)

Characteristics of the signal transduction in Platelet activating factor (PAF)-activated platelets and effects of anti-platelet agents on this response were investigated in vitro for potential therapeutic applications in canine endotoxemia. Blockade of the PAF receptor by a specific blocker has the strongest inhibitive effect on the PAF-induced platelet reactions. The response was also inhibited by either Ca(2+) channel blockers or prostaglandin E(1).     

Determination of the Chemical Structures of Tandyukisins B–D,Isolated from a Marine Sponge-Derived Fungus

Tandyukisins B–D (1–3), novel decalin derivatives, have been isolated from a strain of Trichoderma harzianum OUPS-111D-4 originally derived from the marine sponge Halichondria okadai, and their structures have been elucidated on the basis of spectroscopic analyses using 1D and 2D NMR techniques. In addition, their chemical structures were established by chemical transformation. They exhibited weak cytotoxicity, but selective growth inhibition on panel screening using 39 human cancer cell lines.     

Lineage specific detection of the scaly form of the pen shell <Emphasis Type="Italic">Atrina</Emphasis> spp. by a loop-mediated isothermal amplification method

Taxonomy of the pen shell (genus Atrina) in East Asia has been confused because of the plasticity of the shell morphology and lack of unified morphological characteristics. We analyzed the mitochondrial cytochrome c oxidase subunit I (COI) sequence of the pen shell sampled from Ariake Bay and Seto Inland Sea, western Japan. All individuals were identified as the scaly form based on external morphology; however, their COI sequences were comprised of two distinct lineages. The sequence divergence between the two was 8.3%, indicating the high possibility that they are different species. The scaly form of the pen shell in Japan is one of the target species for resource enhancement, therefore COI lineage identification of broodstock individuals is critically important to avoid producing hybrid seed. We developed a loop-mediated isothermal amplification method that enables specific detection of the two lineages. This method can contribute to reducing the cost and time required for genotyping broodstock individuals prior to seed production.     

Effect of plant density on growth and yield of new soybean genotypes grown under early planting condition in southwestern Japan

Soybeans planted in early to mid-June (early) are less affected by rainfall during rainy season than those conventionally planted in early to mid-July in southwestern Japan. Also, narrow row cultivation is expected to increase soybean yield and save labor for inter-tillage and ridging. Field experiments were performed in 2014 and 2015 to test the effect of plant density (high, middle, and low) under early planting condition on growth, yield, and several agronomical traits of Sachiyutaka A1 and three new genotypes (Sakukei 155, Kanto 127 and Shikoku 15). Early planting was performed in mid- to late June, even though rainy season started in early June. Higher plant densities produced 13% greater yield than low plant density through an increase in biomass accumulation, especially at R5. Among yield components, only pods m^?2 was significantly and positively correlated with yield, indicating that an increase in pods m^?2 led to a greater yield with higher plant densities. The yields of Sachiyutaka A1 were relatively stable for two years, but the lodging resistance should be further improved. Shikoku 15 had greater yield potential and lodging resistance, but its resistance to damping-off disease should be improved. Sakukei 155 with medium plant density produced relatively high and stable yield with less lodging. Although the yield of Kanto 127 fluctuated between experimental years, this genotype showed higher yield potential in higher plant densities with less lodging in 2015. Thus, Sakukei 155 and Kanto 127 with high or medium density may be suitable for early planting in this region.     

Evaluation of greenhouse gas emissions in a Miscanthus sinensis Andersson-dominated semi-natural grassland in Kumamoto,Japan

Increasing greenhouse gas emissions from anthropogenic activities continue to be a mounting problem worldwide. In the semi-natural Miscanthus sinensis Andersson; grasslands of Aso, Kumamoto, Japan, which have been managed for thousands of years, we measured soil methane (CH₄) and nitrous oxide (N₂O) emissions before and after annual controlled burns. We estimated annual soil carbon (C) accumulation, and CH₄ and N₂O emissions induced by biomass burning in 2009 and 2010, to determine the impacts of this ecosystem and its management on global warming. Environmental factors affecting soil CH₄ and N₂O fluxes were unknown, with no effect of annual burning observed on short-term soil CH₄ and N₂O emissions. However, deposition of charcoal during burning may have enhanced CH₄ oxidation and N₂O consumption at the study site, given that emissions (CH₄: ?4.33 kg C ha^?1 yr^?1, N₂O: 0.17 kg N ha^?1 yr^?1) were relatively lower than those measured in other land-use types. Despite significant emission of CH₄ and N₂O during yearly burning events in early spring, the M. sinensis semi-natural grassland had a large annual soil C accumulation, which resulted in a global warming potential of ?4.86 Mg CO₂eq ha^?1 yr^?1. Consequently, our results indicate that long-term maintenance of semi-natural M. sinensis grasslands by annual burning can contribute to the mitigation of global warming.     

Excessive application of farmyard manure reduces rice yield and enhances environmental pollution risk in paddy fields

The present study examined the effect of excessive application of farmyard manure (FM) on rice production and environmental pollution in paddy fields of Japan. A long-term field experiment was conducted during the period 1976–2006 to examine the trends of rice yield and yield components as affected by the excessive FM application (20 Mg ha^?1 year^?1 containing 110 kg N, 180 kg P₂O₅, and 320 kg K₂O). Rice growth, soil fertility, and surface water quality were also assessed in the final year (2006). The results obtained were compared with those of a conventional practice with recommended doses of inorganic fertilizer (IF), i.e. 85 kg N, 68 kg P₂O₅, and 53 kg K₂O ha^?1 year^?1, and an unfertilized control (CR). The excessive FM application resulted in a gradual decrease in grain yield, which was mostly explained by the reduction of grain fertility under the luxuriant rice growth. This reduction may have been due to the higher accumulation of soil nutrients such as N, P, and K. Moreover, the excessive FM application increased chemical oxygen demand, total P, and soluble K concentrations in the paddy surface water and their effluent loads compared to the conventional practice with the recommended IF application.     

日本农业推广服务的计算机网络系统及其在福井地区的应用

日本农业推广主要由政府分配的1万名推广顾问到日本各地服务。这项服务由农、林、渔业部以及47个地方政府负责。为满足农业推广服务信息管理的需要,日本大约20年前建立了推广信息中心。并从1988年开始进行全国范围试验性推广计算机网络系统,现在推广信息中心的主要任务是管理一个叫作推广信息网络的计算机网络系统。     

In situ observation of pinewood nematode in wood

In pine wilt disease, xylem dysfunction occurs in relation to nematode migration and proliferation in host tissue, but the detection accuracy of pinewood nematode (PWN), Bursaphelenchus xylophilus, in pine stem tissue remains unclear. This study describes the use of cryo-scanning electron microscopy (cryo-SEM) and fluorescein-conjugated wheat germ agglutinin (F-WGA) staining to detect PWN. After PWN invasion, the frequency of surface fluorescence in PWN increased in pine stems from the day of inoculation to 3 weeks after inoculation. However, the fluorescence frequency decreased significantly during the advanced disease stage after 5 weeks. Thus, detecting PWN based on fluorescent staining of the nematode body surface coat protein can be misleading when used to examine the correlation between the development of disease symptoms and the nematode population. In contrast, all cut body segments were fluorescent, and their fluorescent components were common in pine-stem cross sections, regardless of the timing after inoculation. In addition, PWN were observed under cryo-SEM only in empty resin canals and this distribution was confirmed by F-WGA staining of PWN cut in a cross section. Thus, PWN detection based on fluorescent staining of surface coat proteins by F-WGA was not reliable in longitudinal sections of pine stems because of changes in nematode stainability during disease progression. To detect PWN in infected plants, we concluded that a combination of both methods is most effective.