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1.
TS Kim SH Lee GT Gang YS Lee SU Kim DB Koo MY Shin CK Park DS Lee 《Reproduction in domestic animals》2010,45(5):e201-e206
The sperm‐mediated gene transfer method is applicable to transgenesis in many species that use spermatozoa for reproduction recently, which has been shown various results. In the current study, we show that transgenic porcine embryos can be efficiently produced by employing a simple transfection method that uses magnetic nanoparticles (MNPs). The complexes formed between plasmid DNA and MNPs were bounded on ejaculated boar spermatozoa at a higher efficiency compared to methods using DNA alone or lipofection. Using confocal microscopy, rhodamine fluorophore‐labelled MNPs were detected on external surfaces of the spermatozoa membrane, which were bounded on zona pellucida of in vitro maturated oocyte during in vitro fertilization. Electron microscopy revealed that clusters of MNPs were detected in inside of plasma membrane and nucleus of the spermatozoa head. Additionally, we found that magnetofected boar spermatozoa could be fertilized with oocytes in vitro and that the resulting gene of green fluorescent protein was detected in fertilized eggs by genomic PCR analysis. Taken together, these results suggest that MNPs can be used to efficiently introduce a transgene into embryo via spermatozoa. 相似文献
2.
1 亲本来源辽单 2 7号 (原名辽 940 4 )为辽宁省农业科学院作物研究所以自选系辽 2 30 9为母本 ,引入系丹340为父本杂交组配而成。辽 2 30 9自选系是 1 990年以美国先锋杂交种7861 3(ｏｐ)为基础材料连续自交多代选择育成。辽 2 30 9一般配合力高 ,高抗大、小斑病和丝黑穗病 ,抗病毒病和茎基腐病 ,秆硬抗倒 ,株形紧凑 ,活秆成熟 ,产量高。2 辽单 2 7号选育经过1 992年冬在海南岛测配时用丹 340 (是当时测验种之一 )配制成辽 2 30 9×丹 340杂交组合。1 993～ 1 994年进行院内品比试验。 1 995年参加辽宁省区域试验预备试验 ,1 996～ 1 997… 相似文献
3.
Natural transmission of bovine leukaemia virus (BLV) infection in south-eastern Queensland dairy herds was slow in 2 herds with a low to moderate (13 to 22%) prevalence of infection. Infection spread much more rapidly in a herd that had a higher prevalence (42%) when first tested. In a 13 month study of this herd, the cumulative incidence of infection was 24%. In one herd new infections were confined almost entirely to calves of uninfected dams. Following the end of feeding bulk milk to calves, a common practice in dairy herds, no more calves in this herd became infected. In laboratory experiments, neither prolonged housing of susceptible calves with infected cattle, consumption of drinking water contaminated with infected blood, nor inoculation of sheep with saliva from infected cattle resulted in transmission of BLV infection. Sheep were infected by subcutaneous inoculation of a suspension of purified lymphocytes from an infected heifer. The minimum infective dose was 10(3) lymphocytes, equivalent to the number of lymphocytes in approximately 0.1 microliter blood. Thus, procedures involving the transfer of a very small volume of blood from animal-to-animal have the potential to transmit infection. 相似文献
4.
Y.S. Saharawat Bhagat Singh R.K. Malik Jagdish K. Ladha M. Gathala M.L. Jat V. Kumar 《Field Crops Research》2010
The rice–wheat rotation covering 13.5 million ha in the Indo-Gangetic Plains is vital for food security. Its sustainability is at risk as the current production practices are inadequate resulting in high cost of cultivation and inefficient use of inputs (i.e. water, labor and energy). In a field study, we evaluated resource conserving and cost-saving alternative tillage and crop establishment options with an aim to improve system productivity and efficiency. Treatments included transplanting and direct-seeding of rice after reduced and no-tillage, followed by wheat after no-tillage. Conventional-tilled (puddled) transplanted rice followed by conventional-tilled wheat was included as a current practice. Rice yields of transplanted rice were similar irrespective of tillage/puddling. However, both dry and wet direct-seeded rice yielded 0.45–0.61 Mg ha−1 lower than puddled transplanted rice. Wheat yield after no-tillage was either higher or equivalent to conventional practice. Wheat provided more economic return (US $35 ha−1) than rice. No-till wheat was 6% more profitable than the conventional practice (T1). Rice transplanting with or without puddling had similar water application but dry direct-seeded rice had 10–12% lower and wet direct-seeded rice 20–24% higher. Machine labor without tillage was lower by maximum of 51 and 43% in rice and wheat, respectively. Similarly, human labor was also 9–16% lower in no-till rice compared to other practices. Two years results consistently showed $35 more net income when rice was transplanted without puddling than that of conventional practice. Direct-seeded/un-tilled rice had variable response in 2 years; US $16 more in year 1 and similar in year 2 to the puddled transplanted rice. Direct-seeded or transplanted rice after no-tillage can be more efficient and profitable alternatives to current practice (puddled transplanted rice), however, require further refinement in areas of cultivar development for no-till direct-seeding condition, nutrient, water and weed management to harness maximal potential. 相似文献
5.
The migration of fish from two large northern Finnish lakes to their outflowing rivers was studied by echosounding and exploratory fishing. Both lakes are regulated for hydroelectric purposes. In both rivers, two sonar stations with stationary up- and down-looking transducers were used to collect data for one year. The fish migration rate in the River Oulujoki was greater than in the River Paatsjoki. In the River Oulujoki, the fish migrated mainly downstream and in the River Paatsjoki both down- and upstream. In the River Paatsjoki, larger fish showed active migration in the spring and autumn, whereas in the River Oulujoki the increase in the migration occurred simultaneously in all size groups. The different species composition and the different nature of the lakes, together with the different regulation practices, were considered to be responsible for the varying migration patterns. It was concluded that no barriers to fish migration should be built on these rivers. 相似文献
6.
B Zhang LQ Che Y Lin Y Zhuo ZF Fang SY Xu J Song YS Wang Y Liu P Wang D Wu 《Reproduction in domestic animals》2014,49(5):740-745
The effect of dietary N‐carbamylglutamate (NCG) supplementation during the entire gestation on reproductive performance of gilts was determined. At the initial day of gestation, forty‐five cross‐bred (Landrace × Large white) gilts were randomly assigned to five groups receiving a basal diet (control group) and basal diet supplemented with 0.05%, 0.10%, 0.15% and 0.20% NCG until parturition, respectively. At parturition, total litter size, live litter size and rate of stillbirth were not markedly affected by NCG supplementation. However, gilts in 0.05% NCG‐supplemented group had more pigs born alive than gilts in control group (+1.11 pigs, p = 0.12), and live litter weight was increased (+12.13–19.17%, p < 0.05) in 0.05%, 0.10% and 0.15% NCG‐supplemented groups relative to control group. And also, average birthweight of piglets born alive was higher (+6.57%, p < 0.05) in 0.05% NCG‐supplemented group than in control group. Furthermore, on days 30, 60, 90 and 110 of gestation, concentrations of arginine and ornithine in plasma were higher (p < 0.05) in 0.05%, 0.10%, 0.15% and 0.20% NCG‐supplemented groups than in control group, respectively. In addition, the chorioallantois gene expression of endothelial nitric oxide synthase (eNOS), vascular endothelial growth factor A (VEGF‐A), placental growth factor (PLGF) and angiopoietin‐2 (ANG‐2) was all increased (p < 0.05) in 0.05%, 0.10% and 0.15% NCG‐supplemented groups than in control group. In conclusion, dietary supplementation with 500 mg/kg NCG during the entire gestation significantly improves pregnancy outcomes in gilts, which may be associated with the improved concentrations of arginine in plasma and placental angiogenic factors gene expression of gilts. 相似文献
7.
SR Lee J-W Kim BS Kim D-H Yoo YS Park T-H Lee J-H Ha B-H Hyun ZY Ryoo 《Reproduction in domestic animals》2009,44(5):740-744
In this study, we investigated parthenogenetic induction of canine oocytes by electrical stimulation following Ca-EDTA treatment. Oocyte maturation, parthenogenetic development, and cleavage rate in canine after various electrical stimulations (1.5, 1.8, 2.1 kV/cm) for 50 μs with single DC pulse following 1 mM Ca-EDTA treatment were investigated. In oocyte activated electrically at the voltage of 1.5 kV/cm after 1 mM Ca-EDTA treatment, the rate of pronucleus and two-cell was 4.1% and 2.7%, respectively. Although electrical stimulation could parthenogenetically induce immature oocyte to cleavage stage, degeneration rate in all experimental groups was more than 60%. This means that electrical stimulation after Ca-EDTA treatment could cause canine oocytes to be degenerated. However, two-cell in canine oocyte by parthenogenesis was for the first time induced. Therefore, we suggested that electrical stimulation for canine oocytes could induce parthenogenetically early embryonic cleavage. This result can be used as a basic data for parthenogenesis study in canine. Also, to perform more developed embryonic development, further study to parthenogenesis in canine need to be developed. 相似文献
8.
BS Kim SR Lee BH Hyun MJ Shin DH Yoo S Lee YS Park JH Ha ZY Ryoo 《Reproduction in domestic animals》2010,45(1):13-18
The objective of this study was to determine the effects of gonadotropins on in vitro maturation (IVM) and electrical stimulation on the parthenogenesis of canine oocytes. In experiment I, cumulus oocyte complexes were collected from ovaries at a random phase of the oestrus cycle and cultured on maturation medium treated with hCG or eCG for 48 or 72 h. There were no significant differences in the effects on the metaphase II (MII) rate between the hCG and eCG treatment groups over 48 h (5.4% vs 5.5%). The MII rate in the co-treatment group of hCG and eCG for 48 h was higher than in each hormone treated group (15.5%, p < 0.05). In experiment 2, the parthenogenetic effect on oocyte development, at various electrical field strengths (1.0, 1.5, 2.0 kV/cm DC) for 60 or 80 μs with a single DC pulse after IVM on the co-treatment of hCG and eCG, was examined. The rate of pronuclear formation (37.1%) in electrical activation at 1.5 kV/60 μs without cytochalasin B (CB) was higher than that of oocytes activated in the other groups (p < 0.05). However, we did not observe the cleavage stages. Also, CB did not influence parthenogenesis of canine oocytes. The results showed that the pronucleus formation rate, indicative of the parthenogenesis start point, could be increased by electrical stimulation. Therefore, these results can provide important data for the parthenogenesis of canine oocytes and suggest the probability of parthenogenesis in canines. 相似文献
9.
Sanjay Kumar B. S. Tomar Y. S. Saharawat Ajay Arora 《Journal of plant nutrition》2018,41(9):1155-1162
The present experiment was conducted to investigate the effect of foliar spray of mineral nutrients on plant growth, seed yield, and quality attributes in onion cv. Pusa Riddhi at SPU, IARI, New Delhi during rabi 2013–14 and 2014–15. The experiment consisted of 16 treatments comprised of boron, zinc, calcium, and magnesium laid out in a completely randomized block design with two replications. The study revealed that the foliar zinc spray (625 g ha?1) produced higher seed scape height (105.35 cm) along with lower disease incidence (8.50%) than the other treatments. Whereas, higher number of seed scapes plant?1 (11.20) and productive seed scapes plant?1 (8.58) were observed in T10 (500 g ha?1) and combined spray of B + Zn + Ca (T14), respectively. The flowering traits, viz., umbellates umbel?1 (642.45), productive umbellates umbel?1 (579.35), and umbel diameter (7.38cm) were significantly (p ≤ 0.05) higher in T15 than other treatments. Similarly, higher seed yield and seed quality attributes were also observed in combined application of all minerals treatment (T15). 相似文献
10.
