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92.
Tropical Animal Health and Production - The purpose of this study was to investigate the ovarian condition at weaning and subsequent reproductive performance of Berkshire sows following an outbreak...  相似文献   
93.
This paper introduces the Agriculture, Forestry and Fisheries Research Council of Japan (AFFRC) model, an integrated model that predicts future rice production in the Mekong River basin by taking into account the effect of global warming on both the water cycle and the rice economy. The model focuses especially on the water balance of paddy fields for different farmland water use systems. We defined six categories of irrigated paddies and three categories of rain-fed paddies on the basis of their systems of water usage. We included a process-based model to predict future rice production, accounting for daily changes in available water resources such as precipitation. Many models of crop production treat rice in the same way as other crops; the particular characteristics of rice farming are considered in more detail in our model. Our results show that it is possible to estimate future rice production in the Mekong River basin by taking into account changes in available water, and to model the resultant effects on the grain market.  相似文献   
94.
Water management practices, such as midseason drainage (MD) and intermittent irrigation, are effective in reducing methane (CH4) emission from irrigated rice paddies. In a previous study in which two-year field experiments were conducted at nine sites across Japan, prolonged MD was found to reduce the seasonal total CH4 emission by 30.5?±?6.7 % (mean?±?95 % confidence interval) compared with conventional MD without compromising rice grain yield. However, the degree of CH4 reduction by water management is dependent on prevailing weather conditions. To estimate the mean effect of prolonged MD on CH4 emission at the nine sites with rice straw application, we conducted a long-term (20 years) simulation using a process-based biogeochemistry model, the DNDC-Rice. The model adjusted using site-specific parameters was able to reproduce the measured magnitude of the total CH4 emission and the suppressive effect of prolonged MD. The number of nonrainy days during MD explained the degree of CH4 reduction for each site and all sites combined. In the simulation, mean reduction percentage was 20.1?±?5.6 % when acceptable prolonged MD (i.e., having less than 15 % yield loss) was applied compared with conventional MD. The discrepancy of the percentage between measurement and simulation was primarily attributable to longer nonrainy days during prolonged MD at several sites in the measurement than the mean of 20-year simulation. We therefore conclude that the long-term simulation better represents the mean reduction percentage of CH4 emission by prolonged MD relative to conventional MD at the nine sites across Japan.  相似文献   
95.
Peaton virus (PEAV) is a type of arthropod-borne virus (arbovirus) belonging to the genus Orthobunyavirus, much like Akabane virus and Aino virus. These arboviruses cause stillbirth and congenital malformations of fetuses in ruminants. In Japan, abnormal birth in bovine caused by PEAV were reported in Okinawa, Kyushu, and Chugoku regions, but it has never been reported in Shikoku region. The abnormal birth occurred in 2020 in Ehime Prefecture (Shikoku region) and suspected of being caused by PEAV from results of clinical signs, pathological findings, and virus neutralization test using PEAV. However, PEAV was not detected and isolated. This report describes the case of abnormal birth in bovine suspected of being caused by PEAV first occurred in Shikoku region, Japan.  相似文献   
96.
This study was undertaken to identify critical and practical factors explaining spatial variations in soil respiration and to estimate stand-scale soil respiration in an aseasonal tropical rainforest on Borneo Island. To this aim, we conducted soil respiration measurements at 25 points in a 40 m × 40 m subplot of a 4 ha study plot between 2002 and 2006, and examined the spatial variation in soil respiration averaged over the 4 years in relation to soil, root, and forest structural factors. In addition, we examined the spatial representativeness of soil respiration measured in the subplot using a specific scaling procedure. Consequently, we found significant positive correlation between the soil respiration and forest structural parameters such as the mean diameter at breast height (DBH), total basal area, and maximum DBH within 6 m of the measurement points. The most important factor was the mean DBH within 6 m of the measurement points, which had a significant linear relationship with soil respiration. Using the derived linear regression and an inventory dataset, we estimated the 4 ha plot-scale soil respiration. The 4 ha plot-scale estimation (6.0 μmol m−2 s−1) was nearly identical to the subplot-scale measurements (5.7 μmol m−2 s−1), which were roughly comparable to the nocturnal CO2 fluxes calculated using the eddy covariance technique. In addition, we discuss characteristics of the stand-scale soil respiration at this site by comparing with those of other forests reported in previous literature in terms of the soil C balance. Soil respiration at our site was noticeably greater, relative to the incident litterfall amount, than soil respiration in other tropical and temperate forests probably owing to the larger total belowground C allocation by emergent trees. Overall, this study suggests the arrangement of emergent trees with larger DBH and their belowground C allocation could be primary factors controlling spatial variations in soil respiration in the tropical rainforest.  相似文献   
97.
Potassium bromide overdose (bromism) in the management of canine epilepsy has been known. However, a protocol to reduce bromide concentrations rapidly has not been previously established. The effects of three infusion fluids with different chloride contents on the steady‐state serum concentrations of bromide in beagles were determined. After stabilization of the serum bromide concentrations, seven dogs were infused with saline (Na+ 154 mmol/L; Cl? 154 mmol/L), lactated Ringer's (Na+ 131 mmol/L; Cl? 110 mmol/L), or maintenance solutions (Na+ 35 mmol/L; Cl? 35 mmol/L) at a rate of 2 or 10 ml kg?1 hr?1 for 5 hr. Serum and urine were collected hourly, and the bromide concentrations were measured. When saline and lactated Ringer's solutions were infused at a rate of 10 ml kg?1 hr?1 for 5 hr, serum bromide concentrations were decreased by 14.24% and urine bromide concentrations by 17.63%, respectively. Of all compositions of infusion fluids, only sodium and chloride contents were associated with the decreased serum concentrations and the increased renal clearance of bromide. In summary, saline and lactated Ringer's solutions reduced serum bromide concentrations in a sodium chloride‐dependent manner in dogs were found when infused at 10 ml kg?1 hr?1 for 5 hr.  相似文献   
98.
ABSTRACT:   Thermally induced gelation of paramyosin from scallop smooth adductor muscle was investigated by dynamic rheological measurements under various conditions. The paramyosin thermal gel was produced at pH 6.5 and 7.2 at temperatures above 30°C through a two-step increase in storage (G') and loss (G') moduli; these values were higher than in gels produced from actomyosin at a high temperature. The thermal gel properties were very firm and brittle. In contrast, one main peak of G' was observed during gelation at pH 8.0. The gel produced at pH 8.0 was more transparent and less soluble in a 6 M urea−0.5 M NaCl solution than those formed either at pH 6.5 or 7.2. These differences in the thermal gel properties are presumed to derive from the pH dependence of the gel matrix-forming process, such as oxidative cross-linking between cysteine residues, rather than from the thermal unfolding of the paramyosin molecules. The thermal gelation profile of chymotrypsin-digested paramyosin showed marked depression of G' at high temperature.  相似文献   
99.
Repetitive DNA sequences, ManDra and ManBgl, were isolated from the DraI and BglII digests of the genomic DNA of Misgurnus anguillicaudatus, respectively. A primer set of ManDra distinguished two genetically different groups (A and B) of M. anguillicaudatus by specific electrophoretograms. A primer set of ManBgl amplified the DNA of M. anguillicaudatus and M. mizolepis. The individuals of M. anguillicaudatus were divided into two groups depending on the fragment sizes, in which the groups A and B (B-1 and B-2) showed 400 and 460 bp, respectively. M. mizolepis was distinguished by a different pattern (400-, 460-, and 510-bp fragments). PCR–RFLP analyses of recombination activating gene 1 gave a clear difference between A or B-2 (443-bp fragment) and B-1 groups (296- and 147-bp fragments). Clonal lineages and hybrids between B-1 and B-2 groups could be identified by appearance of three fragments (443, 296, and 147 bp). The combined analyses using the above three nuclear markers discriminated among nuclear genomes of genetic groups (A, B-1 and B-2) of M. anguillicaudatus and M. mizolepis. In several localities, natural hybridizations between the group B-1 and B-2 loaches and introgressions of clonal mitochondrial genomes into the group B-1 loaches were detected.  相似文献   
100.
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