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331.
Eun Young KIM Dong Hwan SONG Min Jee PARK Hyo Young PARK Seung Eun LEE Hyun Yong CHOI Jeremiah Jiman MOON Young Hoon KIM Seong Ho MUN Chang Eon OH Moon Suck KO Dong Sun LEE Key Zung RIU Se Pill PARK 《The Journal of reproduction and development》2013,59(6):536-543
To preserve Jeju black cattle (JBC; endangered native Korean cattle), a pair of
cattle, namely a post-death cloned JBC bull and cow, were produced by somatic cell
nuclear transfer (SCNT) in a previous study. In the present study, we examined the
in vitro fertilization and reproductive potentials of these
post-death cloned animals. Sperm motility, in vitro fertilization
and developmental capacity were examined in a post-death cloned bull (Heuk Oll Dolee)
and an extinct nuclear donor bull (BK94-13). We assessed reproductive ability in
another post-death cloned cow (Heuk Woo Sunee) using cloned sperm for artificial
insemination (AI). There were no differences in sperm motility or developmental
potential of in vitro fertilized embryos between the post-death
cloned bull and its extinct nuclear donor bull; however, the embryo development ratio
was slightly higher in the cloned sperm group than in the nuclear donor sperm group.
After one attempt at AI, the post-death cloned JBC cow became pregnant, and gestation
proceeded normally until day 287. From this post-death cloned sire and dam, a JBC
male calf (Heuk Woo Dolee) was delivered naturally (weight, 25 kg). The genetic
paternity/maternity of the cloned JBC bull and cow with regard to their offspring was
confirmed using International Society for Animal Genetics standard microsatellite
markers. Presently, Heuk Woo Dolee is 5 months of age and growing normally. In
addition, there were no significant differences in blood chemistry among the
post-death cloned JBC bull, the cow, their offspring and cattle bred by AI. This is
the first report showing that a pair of cattle, namely, a post-death cloned JBC bull
and cow, had normal fertility. Therefore, SCNT can be used effectively to increase
the population of endangered JBC. 相似文献
332.
LEE CC 《Science (New York, N.Y.)》1959,129(3358):1280
Thatcher wheat grown in soil to which Sr(90) had been added showed that accumulation of radioactivity in the kernels was about one-tenth the accumulation in leaves and stems. Experimental milling of the kernels gave brans with the largest amounts and flours with the least amounts of activity, the Sr(90) concentrations being related practically linearly to the weights of total ash in the various milling products. 相似文献
333.
Effects of drought stress on root morphology and spatial distribution of soybean and adzuki bean 下载免费PDF全文
Hyen Chung CHUN Sanghun LEE Young Dae CHOI Dong Hyeok GONG Ki Youl JUNG 《农业科学学报》2021,20(10):2639-2651
Due to global climate change, Korea is facing severe droughts that affect the planting and early vegetative periods of upland crops. Soybean and adzuki bean are important legume crops in Korea, so it is critical to understand their adaptations to water stress. This study investigated the changes in root morphological properties in soybean and adzuki bean and quantified the findings using fractal analysis. The experiment was performed at the National Institute of Crop Science in Miryang, Korea. Soybeans and adzuki beans were planted in test boxes and grown for 30 days. The boxes were filled with bed soil with various soil moisture treatments. Root images were obtained and scanned every two days, and the root properties were characterized by root length, depth and surface area, number of roots, and fractal parameters(fractal dimension and lacunarity). Root depth, length and surface area and the number of roots increased in both crops as the soil moisture content increased. The fractal dimension and lacunarity values increased as the soil moisture content increased. These results indicated that the greater the soil moisture, the more heterogeneous the root structure. Correlation analysis of the morphological properties and fractal parameters indicated that soybean and adzuki bean had different root structure developments. Both soybean and adzuki bean were sensitive to the amount of soil moisture in the early vegetative stage. Soybean required a soil moisture content greater than 70% of the field capacity to develop a full root structure, while adzuki bean required 100% of the field capacity. These results would be useful in understanding the responses of soybean and adzuki bean to water stress and managing irrigation during cultivation. 相似文献
334.
激活的绢云母:一种使水生环境中铯衰减的高效天然粘土物质) 总被引:1,自引:0,他引:1
Sericite is mica-based natural clay that is annealed at 800 ℃ for 4 h, followed by acid activation using 3.0 mol L-1HCl at 100℃. The interaction of cesium(I), Cs(I), with sericite could provide useful data for the study of soil erosion or mass water movement utilizing the natural radioactive Cs. In this study sericite and activated sericite were used to assess their suitability in the attenuation of Cs from the aquatic environment under both batch and column experiments. The surface morphological studies indicated that a disordered and heterogeneous surface structure was exhibited by the activated sericite, whereas the native sericite exhibited a compact and layered structure. The Brunauer-Emmett-Teller(BET) specific surface area results indicated a significant increase in the surface area due to the activation of sericite. The batch reactor data collected for various parametric studies revealed that an increase in p H(from 2.0 to 8.0) and sorbate concentration(from 10.0 to 100.0 mg L-1) apparently favored the attenuation of Cs(I). The timedependent sorption data revealed that Cs(I) uptake was very rapid, and it achieved its saturation value within just 50 min of contact.The kinetic modeling studies indicated that the uptake of Cs(I) followed a pseudo-second-order rate equation; hence, the attenuation capacity of these solids for Cs(I) was estimated to be 0.858 and 4.353 mg g-1for sericite and activated sericite solids, respectively.The adsorption isotherm modeling data showed a reasonably good applicability of the Freundlich model than the Langmuir model.The effect of background electrolyte concentrations(0.001 to 0.1 mol L-1) of Mg(NO3)2indicated that the presence of this electrolyte could not significantly affect the percent removal of Cs(I) by activated sericite. Furthermore, the fixed-bed column reactor operations were performed to obtain the breakthrough data, which were fitted well to the Thomas non-linear equation. Therefore, the loading capacity of Cs(I) was estimated to be 1.585 mg g-1at the initial influent Cs(I) concentration of 30.0 mg L-1at p H 5.0. 相似文献
335.
Sung Dae LEE † Hoi Yun KIM † Young Min SONG Hyun Jung JUNG Sang Yun JI Hae Dong JANG Jae Weon RYU June Cheol PARK Hong Kil MOON In Cheul KIM 《Animal Science Journal》2009,80(1):41-45
The aim of the present study was to investigate the effect of Eucommia ulmoides leaf (EUL) supplementation on the growth performance, blood and meat quality parameters in growing and finishing pigs. Ninety gilts (L × LW × D, 20 kg initialBW) were housed 10 per pen in a front‐open building with three replicate pens per treatment. Experimental treatment was started from the beginning of the growing stage (20 ± 3 kg) by supplementing EUL at 0(C), 3(T1) and 5% (T2) to the growing and finishing diet. Pigs were slaughtered by electrical stunning at 105 ± 3 kg live weight. Average daily feed intake (ADFI, kg/day) decreased (P < 0.05) by addition of EUL in growth performance, average daily gain (ADG, kg/day) was lower (P < 0.05) in T1 and T2 than in C. In hematology, leukocytes (WBC, 103/mm3) decreased (P < 0.05) in T1 and T2 than in C. Erythrocytes (RBC, 106/mm3), hemoglobin (HGB, g/dL) and hematocrit (HCT, %) increased (P < 0.05) in T1 and T2 than in C. Platelet (PLT, 103/mm3) was lower (P < 0.05) in T2 than in C and T1. In biochemical composition of serum, total protein (g/dL), r‐GTP (μ/L), total cholesterol (mg/dL) and triglycerides (mg/dL) were lower (P < 0.05) in T1 and T2 than in C. On longissimus dorsi muscle, crude protein was higher (P < 0.05) in T1 than in C. Crude ash was higher (P < 0.05) in T1 and T2 than in C. Yellow to blue color scale (CIE b*) in meat color was higher (P < 0.05) in T2 than in C. CIE b* in back fat color was higher (P < 0.05) in T2 than in the other treatments. In sensory evaluation scores for fresh meat, the values of meat color, fat color, drip loss and marbling were not significantly affected by addition of EUL. In cooked meat, the values of chewiness and overall acceptability were higher (P < 0.05) in T1 and T2 than in C. The results indicate that the addition of EUL affected growth performance, blood parameters and meat quality parameters in growing and finishing pigs. 相似文献
336.
The alpha-macroglobulins are broad-specificity protease inhibitors important in the regulation and clearance from circulation of biologically active proteases. Inappropriate protease activation may be a feature of canine acute pancreatitis and the ability of the animal to clear these proteases may be important in determining survival. An enzyme immunoassay for the detection and measurement of canine alpha-macroglobulins in plasma samples was developed. A reference range for the canine alpha-macroglobulins of 1.20-2.72 mg ml-1 was established from a panel of canine plasma samples, and the stability of the alpha-macroglobulins in plasma samples stored at 4 degrees C was investigated. Changes in the level of the alpha-macroglobulins during disease states involving increased endogenous protease activity can now be investigated using a rapid, repeatable and quantifiable assay. 相似文献
337.
Lina SUSANTI Seonmi KANG Sunhyo KIM Sanghyun PARK Songhui LEE Su An KIM Kangmoon SEO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(9):1395
This study aimed to investigate the effect of mydriasis using topical rocuronium bromide on electroretinography (ERG) in domestic pigeons (Columba livia). Scotopic mixed rod and cone, photopic cone, and photopic flicker ERG were performed on nine eyes of nine healthy adult pigeons under sedation. Each pigeon underwent two sets of ERG recordings. First, without the induction of mydriasis (control) and the second time with the induction of mydriasis using topical rocuronium bromide (treatment). The results were compared using either the Student’s t-test or Wilcoxon rank-sum test, where a P-value of <0.05 was considered statistically significant. No significant differences were observed in the a- and b-wave implicit times and amplitudes during scotopic ERG between the two groups. The a- and b-wave amplitudes in the photopic cone were significantly higher in the treatment group (63.83 ± 32.33 and 191.75 ± 94.46 µV) compared to the control group (46.15 ± 27.60 and 116.76 ± 70.65 µV; P=0.045 and P=0.032, respectively). The photopic flicker amplitude was also significantly higher in the treatment group (76.23 ± 48.56 µV) than in the control group (42.18 ± 31.18 µV; P=0.044). No statistically significant differences were observed in the photopic cone and flicker implicit times between both groups. In conclusions, mydriasis induced by rocuronium bromide in pigeon resulting in higher amplitudes during the photopic ERG but not scotopic ERG. 相似文献
338.
M. L. KEEFER S. R. LEE E. L. JOHNSON M. L. MOSER 《Fisheries Management and Ecology》2011,18(3):177-189
Abstract An experimental fishway was used to examine adult Pacific lamprey, Lampetra tridentata (Gairdner), behaviour in a series of attraction and passage‐performance tests. Among all experiments, lamprey oriented to the fishway floor and walls and were attracted to both ambient and concentrated flow. When confronted with high‐velocity areas (vertical‐slot and submerged‐orifice weirs), many lamprey failed to pass upstream. However, lamprey were able to find and take advantage of low‐velocity refuges when they were provided. Lamprey climbed shallow‐ and steep‐angled ramps when attraction cues were sufficient and other passage routes were restricted. The combined results demonstrated the passage challenges that fishways designed and operated for salmonids present to non‐salmonid species. They also highlight the importance of evaluating trade‐offs between fishway attraction and passage efficiency. The experiments were integrated with tagging studies and development of lamprey‐specific passage structures, a research combination that provided an effective template for fishway performance evaluations. 相似文献
339.
通过对光谱仪采集的340~1 030 nm柑橘健康与感染黑斑区域光谱进行分析,在探明健康和黑斑病不同症状光谱特性的基础上,提出主成分分析结合特征排序的方法,选择出可识别染病与健康样本的最优波长(525 nm)建立SMO分类模型;基于序列浮动前向选择方法优选出4个特征波长(678、740、794、879 nm),建立C4.5算法识别柑橘黑斑病3种症状的方法。试验结果表明,用525 nm波长建立的SMO分类模型对健康和染病果样本的识别率达99.37%,硬斑型、破裂型和黑斑型症状的识别率分别为81.85%、71.88%和67.57%,3种症状的平均识别率为73.77%,比前人方法提高了12.77个百分点。 相似文献