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71.
l ‐ascorbyl‐2‐monophosphate‐Na/Ca (AMP‐Na/Ca) was used as a vitamin C source to investigate the ascorbic acid (AsA) requirements on growth performance and stress resistance of the post‐larval kuruma shrimp, Marsupenaeus japonicus. Purified carrageenan‐microbound diets with six levels of AMP‐Na/Ca, AsA equivalent to 0, 20, 56, 87, 759 and 1697 mg kg?1 diet were fed to triplicate groups of M. japonicus (mean initial weight 16±0.3 mg) for 30 days. The diets with AsA 0, 20 and 56 mg kg?1 showed high cumulative mortality after 10 days of feeding. After the 30‐day trial, the shrimp fed these diets had significantly lower survival and weight gain (WG, %) than those fed the 87, 759 and 1697 mg AsA kg?1 diets. Specific growth rate and individual dry weight showed the same pattern as WG (%). There were no significant differences in growth performance among the groups fed the AsA levels at 87, 759 and 1697 mg kg?1 at the termination of feeding trial. Broken‐line regression analysis indicated that 91.8 mg AsA kg?1 in the diet was the optimum for post‐larval shrimp. On the other hand, dietary level of more than 800 mg AsA kg?1 was needed to ensure high resistance to stressful conditions such as osmotic and formalin stressors.  相似文献   
72.
A fish bioenergetics model coupled with an ecosystem model was developed to reproduce the growth of Pacific saury. The model spatially covers three different oceanographic spatial domains corresponding to the Kuroshio, Oyashio, and interfrontal (mixed water) regions. In this coupled model, three (small, large, and predatory) zooplankton densities which were derived from the lower trophic level ecosystem model were input to the bioenergetics model of saury as the prey densities. Although certain model parameters were imposed from other species’ bioenergetics, several model parameters were estimated from observational data specific to Pacific saury. The integrated model results reproduced appropriate growth rates of Pacific saury. Model sensitivities to water temperature and prey density are examined and observational methods to evaluate the model parameters are discussed.  相似文献   
73.
A feeding trial using five semi-purified diets (50% crude protein) was conducted to investigate the effects of different dietary amino acid patterns on growth and body composition of juvenile Japanese flounder. The control diet contained casein and gelatin as intact protein sources and four other diets contained 30% casein–gelatin (2:1, w/w) and 20% crystalline amino acids (CAA). CAA were added to the diets to simulate the amino acid pattern found in red sea bream egg protein (REP), Japanese flounder larvae whole body protein (FLP), Japanese flounder juvenile whole body protein (FJP), and brown fish meal protein (BFP), respectively. The test diets were fed to triplicate groups of juveniles (2.75±0.05 g) twice a day for 40 days to evaluate weight gain, survival, feed conversion efficiency (FCE), protein efficiency ratio (PER), and apparent protein utilization (APU). The apparent retention of total dietary amino acids in the whole body and A/E ratios of the whole body were also evaluated. The highest weight gain was observed in fish fed the diet containing the dietary amino acid pattern of BFP followed by fish fed the control, FJP, FLP and the REP diets. Percent survival, FCE, PER and APU were also significantly (P<0.05) affected by the amino acid pattern in the diets, indicating the highest value in fish fed the BFP diet. Except for a few amino acids, the amino acid composition of the whole body did not show marked differences with different dietary amino acid pattern. Results suggest that BFP could be more suitable as a reference amino acid pattern in the diet of juvenile Japanese flounder compared to the amino acid pattern of FLP, FJP or REP.  相似文献   
74.
Mechanical stretch induces activation of cultured quiescent satellite cells and the activation response is owing to rapid release of hepatocyte growth factor (HGF) from its extracellular association with satellite cells and its subsequent presentation to the c-met receptor. We provide new evidence that the stretch activation is dependent on nitric oxide (NO) production. Stretch activation could be abolished by the addition of N G-nitro- L -arginine methyl ester (L-NAME), a competitive inhibitor of NO synthesis, but not by N G-nitro- D -arginine methyl ester hydrochloride, a less active enantiomer of L-NAME. Adding HGF to the L-NAME culture restored the activation response, indicating that L-NAME does not directly inhibit satellite cell activation, but acts upstream from the HGF release. In addition, immunoblots of satellite cell lysate revealed the presence of nitric oxide synthase. These experiments suggest that NO is involved in linking mechanical perturbation of satellite cells to chemical signaling responsible for HGF release from its sequestration in vitro .  相似文献   
75.
A total of 568 normal feces from calves on a beef farm in Fukui Prefecture, Japan, in 2011–2012 were examined by RT-semi-nested PCR for rotavirus A (RVA) VP4 genes. Through partial sequencing and BLAST analyses of 84 VP4-positive specimens, we identified an avian-like RVA strain, N2342, which shares highest nucleotide identity (80.0%) with known avian-like bovine strain 993/83, in one specimen. Phylogenetic analysis also revealed a close genetic relationship between N2342 and avian RVAs, suggesting bird-to-cattle transmission. We observed frequent contact of wild birds with calves in the farm, suggesting that these birds were the source of the virus.  相似文献   
76.
A 2-month-old male Japanese Black calf was presented with a 30-day history of progressive ataxia. Antemortem examination using computed tomography (CT) revealed narrowing of the disc spaces due to destruction of intervertebral structures between the first and second thoracic vertebrae and between the second and third thoracic vertebrae. Osteolysis was evident as irregular hypoattenuating lesions within the opposing end plates of the first, second and third thoracic vertebrae. Pseudomonas aeruginosa was detected as the causative bacteria, and discospondylitis was diagnosed. To the best of our knowledge, this is the first bovine case report describing the application of CT for the diagnosis of discospondylitis.  相似文献   
77.
We investigated the relationships between starch concentrations and activities of starch synthetic enzymes in sago palms (Metroxylon sagu Rottb.) under acid sulfate and mineral soil conditions. Plants grown naturally that had reached their maturated stage were sampled. We found that the growth in acid sulfate soil is lower than that in mineral soil and that starch granules were larger and there was more amylase activity in acid sulfate soil than in mineral soil. Lower amylase activity in mineral soil could eliminate the degradation of starch, making the smaller granules suitable for storing large amounts of starch in a limited space inside cells.  相似文献   
78.
Field experiments were conducted on a volcanic ash soil with low available Mo and moderate acidity for 4 years to determine thfc responses of soybeans and soybean nodules to Mo application with seed treatment.

Mo application resulted in a 15.7% increase in the average yield of the nodulated varieties over 4 seasons. However, the genetically controlled non-nodulating variety did not respond to Mo under the same experimental conditions. Nodulated plants treated with Mo became increasingly greener from the pre-bloom stage and contained much more N in their tops during the later period of growth and accumulated considerably larger amount of N in seeds produced per unit area. These results are in agreement with the enhancement of N, fixing activity per plant basis during a long period covered from the stage of 2nd trifoliate leaf unfolding to that of seed development. The increase of yield obtained by the Mo application is ascribed to the improvement of N, fixing activity of the root nodules, The enhancement of N, fixing activity was mainly due to a higher activity per unit nodule weight at early itaget and was due to better growth of nodules during the latter half of growth. Nodules on Mo-created plants were characteristically larger size, had lower water contcnt and higher Mo content.

Referring to the data presented by the authors and several other investigators on available Mo in soils, soil pit, and other related factors, discussion is made that the yield response of soybeans to Mo application is expected in a good number of fields in Japan as a result of nodule response leading to the enhancement of symbiotic N, fixation throughout growth.  相似文献   
79.
Clubroot disease, caused by Plasmodiophora brassicae Woronin, affects various cruciferous crops. Variations in pathogenicity and virulence are present among field populations of P. brassicae. Many races (pathotypes) have been reported in Japan as well as in other countries using various differential systems. Populations can be classified into four pathotypes using two clubroot-resistant (CR) cultivars of Chinese cabbage as differential hosts in Japan. However, it was recently indicated that each population is often heterogenic and composed of multiple genotypes (races or pathotypes). Breakdown in CR cultivars of Chinese cabbage is a problem in some areas of Japan and may contribute to the selective propagation of minor pathogenic genotypes on the CR cultivars. Clubroot has also been recorded on five species of cruciferous weeds in Japan. In particular, clubroot of Cardamine flexuosa is widely distributed in Japan. Some populations of C. flexuosa are often moderately pathogenic on Chinese cabbage and turnip. Therefore, the epidemiological relationship between clubroot of cruciferous crops and that of the weed has been noted but not thoroughly clarified. The relationship between pathogenic and genetic variations has also been examined among populations from cruciferous crops and weeds in Japan. The result implies an interesting genetic relationship among Williams’ races, among pathotypes determined using CR cultivars of Chinese cabbage and among populations from crops and C. flexuosa. This review includes an introduction of the status of studies on pathogenic and genetic diversity in P. brassicae from Japan.  相似文献   
80.
A potyvirus tentatively named Ornithogalum virus 3 (OV-3) was successfully isolated by single-aphid transmissions from O. thyrsoides mix-infected with OV-3, Ornithogalum mosaic virus (OrMV) and Ornithogalum stripe mosaic virus (OrSMV). OV-3, a flexuous, rod-shaped particle of ca. 690 nm, was sap and aphid transmissible. The virus had a narrow host range and caused necrotic mosaic on O. thyrsoides under cold conditions. We therefore propose the name Ornithogalum necrotic mosaic virus (OrNMV) for OV-3. A synergistic increase in symptom severity was apparent on O. thyrsoides mix-infected with OrSMV/OrNMV, but not with either OrMV/OrNMV or OrMV/OrSMV. The nucleotide sequence data reported is available in the DDBJ/EMBL/GenBank databases under accession number AB282754.  相似文献   
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