Low water exchange Gracilariopsis bailiniae Zhang & B.M. Xia culture in intensive milkfish culture effluents: effects of seaweed density on seaweed production and effluent treatment     

Rhea Joy Carton-Kawagoshi  Bessie Joy Elle  Valeriano Corre Jr.  Shuichi Satoh  Masahiro Notoya  Daisuke Fujita 《Aquaculture International》2014,22(2):573-584

This study tested the feasibility of a low-cost seaweed biofiltration system for pond-based aquaculture through an indoor-integrated fish-seaweed culture experiment using weekly nutrient supply regime and different seaweed stocking densities. The culture experiment was conducted in glass aquaria that were stocked with Gracilariopsis bailiniae at 3 densities (low = 0.5 kg m^?2, middle = 2 kg m^?2 and high = 3.5 kg m^?2) and provided either with effluents from intensive milkfish (Chanos chanos) culture or with effluent-free seawater (control) as nutrient source. Stocking density was used as a factor in optimizing nutrient availability for growth and nutrient removal under such low water exchange conditions. Our results showed that G. bailiniae cultivated in milkfish effluents had higher growth, biomass and nitrogen yields than those cultivated in effluent-free seawater. Among the different stocking densities tested, highest growth rate (1.03 % day^?1) was obtained in the middle density. Increasing biomass and nitrogen yields were also obtained at this density until the end of the culture period. Poorer growth rates at low and high stocking densities were attributed to light limitation from phytoplankton and self-shading, respectively. Due to seaweed treatment, average outflow concentration of NH₄ ⁺ was reduced from half of its pretreated level. This study showed that a weekly effluent supply at 2 kg m^?2 seaweed stocking density can sustainably support the growth of G. bailiniae as long as the dissolved nutrients are present at high levels.  相似文献   

Are all three components of conservation agriculture necessary for soil conservation in the Sudan Savanna?     

Kenta Ikazaki  Fujio Nagumo  Saïdou Simporé  Albert Barro 《Soil Science and Plant Nutrition》2018,64(2):230-237

ABSTRACT

Conservation agriculture (CA) as recommended by the Food and Agriculture Organization of the United Nations consists of three components: minimum soil disturbance, soil cover, and crop rotation/association. CA was expected to become an effective countermeasure against water erosion in the Sudan Savanna, but it has not been adopted by local smallholder farmers. As markets for grain legumes (including cowpea) have not been developed in the Sudan Savanna, crop rotation/association should be considered impractical for these farmers. Therefore, we examined whether legume intercropping as a crop rotation/association component is necessary for preventing soil erosion in the Sudan Savanna. Three-year field experiments were conducted in runoff plots at Institute of Environment and Agricultural Research Saria station. The four treatments were conventional practice (full tillage, no sorghum residue mulching, and no intercropping), two-component CA (minimum tillage (MT) and sorghum residue mulching without intercropping), and three-component CA with velvet bean (VB) or pigeon pea (PP) intercropping. It was revealed that: (1) MT and sorghum residue mulching (without intercropping) effectively reduced the annual soil loss by 54% mainly due to the improvement of soil permeability by the boring of termites and wolf spiders found under the sorghum stover mulch; (2) intercropping in combination with MT and crop residue mulching had no effect on soil erosion control mainly because: (a) PP did not survive the long dry season; (b) VB did not serve effectively as a cover crop since soil loss was concentrated at the beginning of the rainy season when VB was still too small; (c) unexpectedly, in combination with MT and crop residue mulching, intercropping with VB did not increase mulch biomass, especially sorghum biomass which prompts the boring of termites and wolf spiders. These results demonstrate that the third component of CA, namely legume intercropping, is not always necessary; rather, the two remaining components – minimum soil disturbance and soil cover – are sufficient for soil conservation in the Sudan Savanna. This finding lightens the burden of adopting CA and thus facilitates its future promotion to the smallholder farmers in the Sudan Savanna.  相似文献   

Evaluation of a recombinant measles virus expressing hepatitis C virus envelope proteins by infection of human PBL-NOD/Scid/Jak3null mouse     

Masaaki Satoh  Makoto Saito  Kohsuke Tanaka  Sumako Iwanaga  Salem Nagla Elwy Salem Ali  Takahiro Seki  Seiji Okada  Michinori Kohara  Shinji Harada  Chieko Kai  Kyoko Tsukiyama-Kohara   《Comparative immunology, microbiology and infectious diseases》2010,33(6):e81-e88

In this study, we infected NOD/Scid/Jak3null mice engrafted human peripheral blood leukocytes (hu-PBL-NOJ) with measles virus Edmonston B strain (MV-Edm) expressing hepatitis C virus (HCV) envelope proteins (rMV-E1E2) to evaluate the immunogenicity as a vaccine candidate. Although human leukocytes could be isolated from the spleen of mock-infected mice during the 2-weeks experiment, the proportion of engrafted human leukocytes in mice infected with MV (10³–10⁵ pfu) or rMV-E1E2 (10⁴ pfu) was decreased. Viral infection of the splenocytes was confirmed by the development of cytopathic effects (CPEs) in co-cultures of splenocytes and B95a cells and verified using RT-PCR. Finally, human antibodies against MV were more frequently observed than E2-specific antibodies in serum from mice infected with a low dose of virus (MV, 10⁰–10¹ pfu, and rMV-E1E2, 10¹–10² pfu). These results showed the possibility of hu-PBL-NOJ mice for the evaluation of the immunogenicity of viral proteins.  相似文献   

The complete mitochondrial genome of the domestic red deer (Cervus elaphus) of New Zealand and its phylogenic position within the family Cervidae     

Kenta WADA  Kazuhiro OKUMURA  Masahide NISHIBORI  Yoshiaki KIKKAWA  Michinari YOKOHAMA 《Animal Science Journal》2010,81(5):551-557

We determined the complete nucleotide sequence of the mitochondrial genome of the semidomestic red deer (Cervus elaphus) of New Zealand. The genome was 16 357 bp long and contained 13 protein‐coding genes, 12SrRNA, 16SrRNA, 22 tRNAs and a D‐loop as found in other mammals. Database homology searches showed that the mitochondrial DNA (mtDNA) sequence from the New Zealand semidomestic deer was similar to partial mtDNA sequences from the European, Norwegian (C. e. atlanticus) and Spanish red deer (C. e. hispanicus). Phylogenetic analysis of the mitochondrial protein‐coding regions revealed two well‐defined monophyletic clades in subfamilies Cervinae and Muntiacinae. However, red deer and Sika deer were not found to be close relatives. The analysis did identify the red deer as a sister taxon of a Samber/Sika deer clade, although it was more closely related to the Samber than the Sika group.  相似文献   

Maximum prey size estimation of longtooth grouper,Epinephelus bruneus,using morphological features,and predation experiments on juvenile cannibalism          下载免费PDF全文

Nariaki Inoue  Jun Satoh  Tohru Mekata  Takashi Iwasaki  Koichiro Mori 《Aquaculture Research》2016,47(2):605-611

In fish culture, cannibalism, which induces critical damage, is separated into two types: type I, which occurs in early larval stages when size heterogeneity is low; and type II, which starts in later larval and/or early juvenile stages following type I when size heterogeneity is high. In type II, the cannibal's maximum prey size is limited by its gape size relative to the prey fish body size. Ratios of prey to cannibal body size changes are associated with allometric factors and feeding behaviour with growth. In a previous study on grouper, the maximal prey size was estimated morphologically (i.e., the relationship between gape size and body height). This method is very simple and useful; however, it does not consider allometric factors and feeding behaviour changes; therefore, it probably causes a large estimation error. To overcome this, we present a new method for estimating maximal prey size to determine the size ranges for size grading of longtooth grouper, Epinephelus bruneus, juveniles using predation experiments. It is shown that grouper type II cannibalism is affected by two factors; in early juvenile stages by morphology and in later (TL over 50 mm) by prey size selectivity.  相似文献   

Eastern little tuna,Euthynnus affinis (Cantor, 1849) mature and reproduce within 1 year of rearing in land‐based tanks          下载免费PDF全文

Ryosuke Yazawa  Yutaka Takeuchi  Kenta Satoh  Yuri Machida  Kotaro Amezawa  Naoki Kabeya  Yukinori Shimada  Goro Yoshizaki 《Aquaculture Research》2016,47(12):3800-3810

Eastern little tuna (ELT, Euthynnus affinis) is expected to see use as a novel aquaculture species due to its rapid growth and high economic value. In this study, closing of the complete life cycle of ELT in land‐based tanks was successfully carried out. Seed production of a first generation (F1) derived from wild‐caught ELT broodstock was conducted in 2010, 2011 and 2012. Survival percentages of F1 ELT at 365 days post hatching for the 2010, 2011 and 2012 year classes were 0.9%, 0.4% and 6.3% respectively. On average, F1 ELT were approximately 40 cm in total length and weighed 1500 g by the time they reached 1 year of age. Successful artificial induction of spawning was achieved in 1‐year‐old F1 ELT using a gonadotropin‐releasing hormone analogue (GnRHa). Induction of spawning was successful at the first administration of GnRHa in the 2010, 2011 and 2012 year classes. First spawning was observed at 4 or 5 days post implantation, which indicated that oogenesis and spermatogenesis progressed within 1 year of rearing in land‐based tanks. During spawning periods, the average number of fertilized eggs and the average number of hatched larvae per spawning event in the 2010, 2011 and 2012 year classes were 20,480 eggs day^?1 and 177 larvae day^?1, 39,423 eggs day^?1 and 9347 larvae day^?1, and 819,555 eggs day^?1 and 674,445 larvae day^?1 respectively. Therefore, it was concluded that both male and female ELT reared in land‐based tanks were capable of reproduction at 1 year of age.  相似文献   

Contribution of charcoal to short-term nutrient dynamics after surface fire in the humus layer of a dwarf bamboo-dominated forest     

K. Makoto  H. Shibata  Y. S. Kim  T. Satomura  K. Takagi  M. Nomura  F. Satoh  T. Koike 《Biology and Fertility of Soils》2012,48(5):569-577

Ecological function of charcoal has been mainly investigated by adding charcoal to soil, which is not fully adequate to understand in situ the role in fire-prone forest ecosystem. To determine in situ effects of charcoal on ecosystem functions, such as nutrient availability, we conducted an experimental burning in a Japanese white birch forest with dense coverage of dwarf bamboo in the understory with or without removal of charcoal. Ammonium-N in the remaining humus layer increased immediately after the burning, but decreased to the level of unburnt plots within 1?month of the burning. Removal of charcoal had no significant effect on the NH₄ ⁺-N dynamics. Although burning did not affect NO₃ ^?-N dynamics during the sampling period, charcoal removal led to a slight increase in NO₃ ^?-N. The available P increased immediately after the burning, but then fell at 1?month after burning. Charcoal inhibited the available P depletion and prolonged the high availability of P. Greater availability of P might be due to the adsorption of phosphate in charcoal pores. Exchangeable Ca and Mg increased gradually; charcoal appeared to extend the period of higher concentration of exchangeable Ca and Mg. Charcoal deriving from fire is a key factor in influencing available nutrient in the humus layer of post-fire forests.  相似文献   

Gene response in rice plants treated with continuous fog influenced by pH,was similar to that treated with biotic stress     

Kouji Satoh  Shoko Saji  Shoko Ito  Hideyuki Shimizu  Hikaru Saji  Shoshi Kikuchi 《Rice》2014,7(1):10

Background

Throughout Asia, including Japan, rice plants are cultivated in a wide range of areas from lowlands to highlands and are frequently exposed to fog, including acid fog. Some physiological studies have shown that acid fog can be a stress factor for plants. We analyzed the gene expression profiles of rice plants treated with artificially prepared simulated acid fog (SiAF) or simulated neutral fog (SiNF) for 1 or 7 days.

Results

Microarray analysis results suggested that both the SiAF and the SiNF treatments induced the expression of genes involved in the defense and stress responses in rice plants. Induction of such genes was detected in plants treated with SiAF for 1 day, and the number of induced genes increased in plants treated with SiAF for 7 days. The genes for defense and stress responses were also induced by SiNF for 7 days, although they were not induced by SiNF for 1 day. The gene expression profiles of the SiAF-treated and the SiNF-treated plants were compared to those of plants treated with other stress factors. The comparison revealed that both SiAF and SiNF treatments have similar effects to biotic stresses and ozone stress. The genes encoding NADPH oxidase and germin, which function in apoplasts, were also induced by SiAF, SiNF and biotic stresses.

Conclusions

These findings suggest that both the SiAF and the SiNF treatments may result in oxidative stress through the apoplastic production of reactive oxygen species.  相似文献   

Therapeutic and adverse effects of flunixin-meglumine in adult and young cats     

Takata K  Hikasa Y  Satoh H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(12):1591-1596

In this study, we elucidated the difference in nonsteroidal anti-inflammatory drug sensitivities between young and adult cats on therapeutic and adverse effects. In the prevention of lipopolysaccharide (LPS)-induced hyperthermia using flunixin-meglumine, young (<3 months old) and adult (>12 months old) cats of both sexes were given LPS (0.3 μg/kg, i.v.), and body temperature was measured 24 hr later. Flunixin (1 mg/kg, s.c.) was administered 30 min before the LPS injection. LPS-induced hyperthermia was almost completely inhibited by pre-treatment with flunixin in both adult and young cats. In addition, flunixin showed almost the same antipyretic effects in both young and adult cats. The animals were administered flunixin (1 mg/kg, s.c.) once a day for 3 days, and sacrificed 24 hr later to examine the gastrointestinal mucosal lesions. In adult cats, flunixin caused many severe lesions in the small intestine. In contrast, very few gastrointestinal lesions were produced by flunixin in young cats. In the pharmacokinetics of flunixin, plasma concentrations of flunixin were analysed using a high performance liquid chromatography. There were no significant differences in plasma concentration of flunixin between young and adult cats from 0.5 to 4 hr after the injection. These results demonstrated that NSAIDs could be used more safely in young than in adult cats from the points of gastrointestinal adverse effects. Furthermore, this difference in gastrointestinal lesions between adult and young cats was not related with the plasma concentration of flunixin.  相似文献   

Characteristics of pregelatinized ae mutant rice flours prepared by boiling after preroasting     

Nakamura S  Satoh H  Ohtsubo K 《Journal of agricultural and food chemistry》2011,59(19):10665-10676

As ae mutant rice, such as EM10, lacks the starch branching enzyme IIb, its amylopectin contains more long-chain glucans than that of ordinary Indica and Japonica rice grains. Although boiled grains of ae rice cultivars are too hard and nonsticky for table rice, they are promising in terms of biofunctionality, such as prevention of diabetes. The present paper investigates the characterization of a novel group of four ae mutant rice cultivars (EM72, EM145, EM174, and EM189). They were subjected to the evaluation for their main chemical components, physical properties, and enzyme activities at different grain conditions (raw milled rice, roasted rice, boiled rice, and rice boiled after preroasting). These mutant rice grains are characterized by high apparent amylose, high protein and high glucose contents, high pasting temperature, high α-amylase activities, high resistant starch, and low degree of gelatinization. A novel method was developed to maintain the high resistant starch contents of gelatinized rice grains. Rice boild after preroasting showed a higher ratio of resistant starch and a lower amount of glucose than ordinary boiled rice. It became possible to produce high-quality and biofunctional pregelatinized rice flours by boiling with frozen fruits, such as tomatoes, after rice grains had been preroasted. These ae mutants were found to be suitable materials for rice/fruit or rice/vegetable products to serve as palatable, low-glucose, and high resistant starch rice products.  相似文献