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排序方式: 共有425条查询结果,搜索用时 15 毫秒
31.
Noritaka ADACHI Daisuke YAMAGUCHI Akiyuki WATANABE Narumi MIURA Seiji SUNAGA Hitoshi OISHI Michiko HASHIMOTO Takatsugu OISHI Masaki IWAMOTO Hirofumi HANADA Masanori KUBO Akira ONISHI 《The Journal of reproduction and development》2014,60(2):100-105
The objective of this study was to examine the health and meat production of cloned sows
and their progenies in order to demonstrate the application of somatic cell cloning to the
pig industry. This study compared the growth, reproductive performance, carcass
characteristics and meat quality of Landrace cloned sows, F1 progenies and F2 progenies.
We measured their body weight, growth rate and feed conversion and performed a
pathological analysis of their anatomy to detect abnormalities. Three of the five cloned
pigs were used for a growth test. Cloned pigs grew normally and had characteristics
similar to those of the control purebred Landrace pigs. Two cloned gilts were bred with a
Landrace boar and used for a progeny test. F1 progenies had characteristics similar to
those of the controls. Two of the F1 progeny gilts were bred with a Duroc or Large White
boar and used for the progeny test. F2 progenies grew normally. There were no biological
differences in growth, carcass characteristics and amino acid composition among cloned
sows, F1 progenies, F2 progenies and conventional pigs. The cloned sows and F1 progenies
showed normal reproductive performance. No specific abnormalities were observed by
pathological analysis, with the exception of periarteritis in the F1 progenies. All pigs
had a normal karyotype. These results demonstrate that cloned female pigs and their
progenies have similar growth, reproductive performance and carcass quality
characteristics and that somatic cell cloning could be a useful technique for conserving
superior pig breeds in conventional meat production. 相似文献
32.
Soichi Tanaka Keiichiro Shiraga Yuichi Ogawa Yoshihisa Fujii Shogo Okumura 《Journal of Wood Science》2014,60(2):111-116
The use of an effective medium theory is important when accurately measuring wood density using millimeter and terahertz wave techniques. To confirm the applicability of this theory to the evaluation of wood density, the relative permittivity and dielectric loss of oven-dry flat-sawn specimens of 11 different wood species were measured in a frequency range of 0.15–1.2 THz using a transmission measurement system for terahertz time-domain spectroscopy. A mixture model based on the effective medium theory well explained the density dependence of relative permittivity over the entire frequency range, while it did not fully explain that of dielectric loss, especially for higher frequencies. This indicates that wood scatters the terahertz wave with a wavelength close to the transverse sectional dimensions of the pores in wood in the same way as Mie scattering. It was found from the dielectric loss spectrum of wood substance that the frequency around 0.23 THz was preferable for the nondestructive evaluation of wood. 相似文献
33.
Soichi Tanaka Keiichiro Shiraga Yuichi Ogawa Yoshihisa Fujii Shogo Okumura 《Journal of Wood Science》2014,60(3):194-200
To clarify the effect of pore conformation on the dielectric anisotropy of wood, the relative permittivity along the longitudinal and tangential axes of flat-sawn oven-dry specimens of 12 different wood species was measured using terahertz time-domain transmission spectroscopy and compared with the values calculated using the eigenvalue problem for two-dimensional photonic crystals. The measured dielectric anisotropy, which is the ratio of the relative permittivity along longitudinal axis to that along the tangential axis, was well explained by the calculated value. It was concluded that the ratio of tangential to radial widths of wood pores affects the relative permittivity along the tangential axis, and that the dielectric anisotropy decreased with an increase in the ratio. This discussion can also be applied to the relative permittivity in frequencies below 0.15 THz. These findings show promise as a new method for evaluating the porous structure of wood. 相似文献
34.
Yukinobu Nakamura Koshiro Migita Akihiro Okitani Masanori Matsuishi 《Animal Science Journal》2014,85(5):595-601
Water‐holding capacity (WHC) of heat‐induced pork gels was examined. The heat‐induced gels were obtained from meat homogenates prepared by adding nine volumes of 0.3–0.5 mol/L NaCl solutions containing 9–36 mmol/L disodium inosine‐5′‐monophosphate (IMP) or 9 mmol/L tetrapotassium pyrophosphate (KPP) to minced pork. IMP at 36 mmol/L enhanced the WHC to the same level as attained by KPP. Physical and sensory properties of heat‐induced gels were also examined. The heat‐induced gels were prepared from porcine meat homogenates containing 0.3 mol/L NaCl and 9–36 mmol/L IMP or 9 mmol/L KPP. IMP at 36 mmol/L enhanced the values of hardness, cohesiveness, gumminess and springiness, measured with a Tensipresser, and several organoleptic scores to the same level as the score attained by KPP. Thus, it is concluded that IMP is expected to be a practical substitute for pyrophosphates to improve the quality of sausages. 相似文献
35.
Initial decomposition rates, changes in organic chemical components (acid-insoluble fraction, holocellulose, polyphenols, soluble carbohydrates) and nutrient dynamics (K, Mg, Ca, P, N) were examined for fine roots and leaves of Japanese cypress (Chamaecyparis obtusa). Litterbag experiments designed to evaluate the relative effects of litter type and position of litter supply in the soil were carried out, considering that root and leaf litter typically occupy different locations and have different substrate qualities. Litterbags of roots and leaves were placed at two positions (on the soil surface and in the humus layer), and collected every 3 months over one year. The mass loss rate and N release were slower during root decomposition in the humus layer than during leaf decomposition on the soil surface. These differences between root and leaf decomposition were mainly caused by the litter type, and the effect of the position on decomposition was relatively small. Root litter was less influenced by position related effects, such as differences in humidity, than leaf litter, and this recalcitrant trait to environmental effects may be responsible for the slower mass loss rate and N release in root decomposition. The results of the present study suggest that fine roots are persistent in the soil and serve an important role in N retention in forest ecosystems because of their litter substrate quality. 相似文献
36.
Yasumi Yagasaki Takashi Chishima Masanori Okazaki Du-Sik Jeon Jeong-Hwan Yoo Young-Kull Kim 《Water, air, and soil pollution》2001,130(1-4):1085-1090
The effect of acidic deposition on the soil under red pine forest in Chunchon, Korea was investigated. Precipitation, stream water, and soil solution chemistry were monitored at the watershed from 1997 to 1998. Acidity of the open-bulk precipitation was often neutralized by large amounts of ammonia (NH3) that might have originated from livestock farming and fertilization. Estimated elemental budget at the watershed showed a positive correlation between loss of base cations and proton (H+) production due to nitrogen transformation in soil (ΔH+ NT: ([NH4 +]in-[NH4 +]out)- ([NO3 ?]in-[NO3 ?]out)). When ΔH+ NT increased, concentrations of nitrate in soil solutions also increased. Consequently, pH values of soil solutions decreased, although ion exchange with base cations contributed to buffer reaction. Since acid buffering capacity of the red pine forest soil was small, it was concluded that the input of ammonium nitrogen enhanced nitrification in soil thus causing soil acidification represented by loss of base cations from the watershed. 相似文献
37.
38.
Chihiro Kayo Seiji Hashimoto Atsunori Numata Masanori Hamada 《Journal of Wood Science》2011,57(3):234-240
We compared the greenhouse gas (GHG) emissions from a log pile (LP) to those from a sand compaction pile (SCP) and from cement
deep mixing (CDM) as measures against soil liquefaction, assuming that forest and waste management scenarios influence the
GHG (CO2, CH4, and N2O) balance of wood. We found little difference between the LP and SCP methods with respect to GHG emissions from fossil fuel
and limestone consumption. However, GHG emissions from the CDM method were seven times higher than emissions from the LP method.
In the GHG balance of wood, when the percentage of CH4 emissions from carbon in underground wood was lower than 3.3%, permanent storage in the log achieved greater reductions in
GHG emissions than using the waste log as fuel in place of coal or heavy oil. In order to obtain reductions in GHG emissions
by replacing SCPs or CDM with LPs, sustainable forest management with reforestation and prevention of CH4 emissions from the underground log are essential. Using reforestation, permanent storage of the log, no CH4 emission from the log, and using logging residues instead of coal, the LP can achieve reductions in GHG emissions of 121
tonnes of CO2 per 100 m2 of improvement area by replacing CDM. 相似文献
39.
The effect of soil freeze–thaw cycles on the denitrification potential was examined based on the C2H2 inhibition method. The gross N2O production curve of the soil sample (incubation with C2H2) showed minor changes between the freeze–thaw treatment and the unfrozen control. However, kinetics analysis revealed that
the initial production rate, an indicator of the population density of denitrifying communities, decreased (P = 0.043) and the specific growth rate constant, an indicator of the activity of denitrifying communities, increased (P = 0.039) as a result of the freeze–thaw cycles in five of six soil samples examined. The increase in the specific growth
rate constant suggested the stimulation of the activity of denitrifying communities that survived after the freeze–thaw cycles
and may explain the minor suppression on the gross N2O production in spite of decreasing the population density of denitrifying communities that was suggested by the initial production
rate. The net N2O production curve of the soil sample (incubation without C2H2) showed a remarkable change in one out of six soil samples, and in that one soil sample, N2O release to the atmosphere was largely stimulated (7.6 times) by the freeze–thaw cycles. However, the stimulation of the
N2O release by the freeze–thaw cycles was even observed in two other selected soil samples (4.6 and 1.8 times), suggesting that
an imbalance in the N2O-producing and N2O-reducing activities of denitrifying communities might complementally explain the N2O release stimulated by the freeze–thaw cycles. 相似文献
40.
Three strains—Nocardioides sp. MFC-A, Rhodococcus rhodochrous MFC-B, and Stenotrophomonas sp. MFC-C—were newly isolated from rice soil or bark compost as microorganisms capable of cometabolically degrading mefenacet (2-benzothiazol-2-yloxy-N-methyl-acetanilide). Several other species belonging to the genera Nocardioides, Rhodococcus, and Stenotrophomonas were also capable of degrading mefenacet, suggesting that the ability is not specific to these isolates, but common at least in these genera. N-methylaniline and 2-benzothiazoloxy acetic acid were identified as the metabolites by liquid chromatography-mass spectrometry. Besides mefenacet, the isolates could degrade one or more other amide pesticides, such as flutolanil, mepronil, metolachlor, and pretilachlor. These results indicate that the strains Nocardioides sp. MFC-A, Rhodococcus rhodochrous MFC-B, and Stenotrophomonas sp. MFC-C degrade mefenacet via hydrolysis of the amide bond, but their substrate specificities differ. 相似文献