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1.
Microinjection of exogenous DNA into the cytoplasm of matured oocytes or zygotes is a promising technique to generate transgenic animals. However, the data about the microinjection time and procedure in sheep are limited and have not treated in detail. To obtain more in-depth information, the Sarda sheep oocytes from abattoir-derived ovaries were subjected to IVM and IVF. Then, the GFP plasmid as a reporter gene was injected into the cytoplasm of MII oocytes (n: 95) and zygotes at different post-insemination intervals (6–8 hpi, n: 120; 8–10 hpi, n: 122; 10–12 hpi, n: 110 and 12–14 hpi, n: 96). There were no significant differences in the cleavage rates between the groups. However, blastocyst rate of injected zygotes at all-time intervals was significantly lower than injected MII oocytes and control group (< 0.05). Interestingly, the proportion of GFP-positive embryos was higher at 8–10 hpi compared with other injected groups (4 % versus 0 %, < 0.01). Among these, the proportion of mosaic embryos was high and two of those embryos developed to the blastocyst stage. In conclusion, we settled on the cytoplasmic microinjection of GFP plasmid at 8–10 hpi as an optimized time point for the production of transgenic sheep and subsequent experiments.  相似文献   
2.
为了查明阿尔泰山两河源国家级自然保护区树附生地衣物种组成成分,以及探讨影响该地区树附生地衣群落分布格局与环境因素之间的关系,以附生地衣覆盖度为指标,应用除趋势对应分析(DCA)对样点进行分组,运用典范对应分析(CCA)分析附生地衣分布与环境因素的关系,结果表明:1)阿尔泰山两河源自然保护区树附生地衣共有49种隶属于15科30属。2)根据DCA分析将该地区树附生地衣划分为3个样点组,样点组1共有地衣22种,总盖度为2.639%,物种多样性指数为1.603;样点组2共有地衣27种,地衣总盖度为3.717%,物种多样性最大为1.972;样点组3:共有地衣12种,地衣总覆盖度为1.036%,物种多样性最小量为0.871。3)CCA排序结果表明:低海拔区,人为干扰强度高,地衣多样性较低;中海拔区,森林郁闭度高,湿度适中,干扰较少,地衣多样性较高;高海拔区,森林郁闭度较低,树种较少,光强度较强,干扰较少,主要以壳状地衣为主,多样性较低。  相似文献   
3.
The aim of the present work was to investigate the effect of Rhus coriaria L. inclusion to the diet on some biochemical, haematological parameters and the level of antioxidant status of male rabbits. Adult rabbits were divided into five groups: one control (C) and four experimental groups. Experimental animals received sumac per os in feed in various doses (0.50%, 0.75%, 1.00% and 1.50%) for 90 days. Significant increase in PDWc (platelet distribution width) in E3 group when compared with control group was recorded. Sumac administration resulted in decreased cholesterol levels in all experimental groups vs. control group. Significantly lower level of cholesterol was found in E4 group with highest dose of sumac (1.50%). Higher values of total antioxidant status (TAS) and albumins were observed in all experimental groups in comparison with control group. A significant increase in TAS was detected in group E1 and E4. Concentrations of albumins were significantly higher in groups E3 and E4 vs. control group. Sumac administration had no significant effect on bilirubin content. In conclusion, these results show a positive effect of sumac consumption on antioxidant status and cholesterol level in adult male rabbits.  相似文献   
4.
Endozoochory has been recognised as the most important dispersal mechanism in invasive Prosopis species, because their sugary, tasty pods attract animals and because some of their seeds remain intact after passing through some animals' digestive systems. In this study, we evaluated the role of the camel (Camelus dromedarius) as a potential disperser of the seeds of invasive tree Prosopis juliflora. Four camels of similar weight (ca. 400 kg) and age (ca. 2 years) were each fed with 70 fruits (1000 seeds approximately) of P. juliflora, which were retrieved from the camels' dung at 24‐h intervals for 4 days. The seeds retrieved were tested for germination and viability, along with seeds not eaten by the camels, with and without pericarp. Less than 3% of the seeds eaten were retrieved from the camels' dung. Most of the seeds (74%) were retrieved between 24 and 72 h after ingestion. The passage through the camel gut significantly accelerated and increased seed germination of P. juliflora in comparison with uneaten seeds covered with pericarp (48–75% and 15% respectively). While gut passage liberated P. juliflora seeds from the pericarp, increasing and accelerating their germination, the viability of seeds which had not germinated after germination trials were decreased (ca. ~20%) relative to uneaten seeds that had also not germinated. Our results show that, despite the low recorded seed recovery, camels can potentially disperse seeds of P. juliflora, which is in line with field observation showing P. juliflora expansion along the camels' routes in Gebel Elba National Park, south‐east Egypt.  相似文献   
5.
Septoria tritici blotch (STB), caused by Mycosphaerella graminicola has recently become one of the devastating diseases in Iran causing significant yield losses on most commercial bread and durum wheat cultivars. Iran is located in the Fertile Crescent, a region where wheat was historically domesticated; and, thus, landraces derived from this region are of considerable global interest for identification of new sources of resistance to various stresses. Here, we report on the resistance responses of 45 tetraploid wheat landraces collected from different provinces of Iran to eight M. graminicola isolates. In total 138 isolate-specific resistances were found among all interactions (n = 360). The highest number of specific resistances (30 out of 32 interactions) was found in wheat landraces collected from West Azarbaijan. In contrast, all landraces from Kordestan were highly susceptible to M. graminicola isolates and only one isolate-specific resistance was identified among 106 isolate-wheat interactions. Kermanshah landraces showed the highest resistance variation against different isolates. About 57 isolate-specific resistances were identified among 104 interactions. Ilam landraces were highly resistant to STB as 28 specific resistances were observed among 32 interactions. Markazi (n = 2) and Sistan-Baluchestan (n = 1) were susceptible to all isolates tested. Landraces from Lorestan were generally susceptible to isolates tested as 26 susceptible responses were observed out of 32 interactions. Our results indicate that landraces collected from the Fertile Crescent region may possess diverse effective resistance genes or valuable broad spectrum resistance genes, and that their identification is of interest and can be exploited in breeding programs.  相似文献   
6.

The aim of this study was to evaluate the water and nitrogen use efficiency and some quantitative and qualitative characteristics of forage beet cultivars under the influence of different irrigation methods and nitrogen levels in two cropping years, 2017–18 and 2018–19, at Agricultural Research Station in Karaj, Iran. Experimental factors included the first factor with four irrigation methods (normal leakage, alternate furrow irrigation, fixed furrow irrigation, type (drip-strip)), the second factor was the amount of nitrogen fertilizer with three levels (150, 200 and 250?kg N ha?1) and the third factor included three forage beet cultivars (Sbsi052, Jamon and Kyros). Among irrigation treatments, alternate furrow irrigation and fixed furrow irrigation had the highest sugar content with 9.28% and 9.17%, respectively. The highest yield of digestible organic matter was obtained in leakage irrigation treatment, nitrogen fertilizer of 250?kg ha?1 and in Kyros at the rate of 19.45?t ha?1. The highest yield of root digestible dry matter, potassium, sodium and free nitrogen was observed in leakage irrigation treatment and consumption of 200?kg ha?1 nitrogen was observed in foreign cultivars. The highest crude protein was observed in alternate furrow irrigation conditions with a consumption of 200?kg ha?1 nitrogen in cultivar Sbsi052 at 13.08%. Leakage irrigation and type tape had the highest consumption efficiency and efficiency of nitrogen uptake with application of 150 and 200?kg ha?1 N, and the highest water use efficiency was also observed in leakage irrigation and type tape with application of 250?kg ha?1 N in domestic and foreign cultivars. The type irrigation method showed better quantitative and qualitative yield than the furrow irrigation methods.

  相似文献   
7.
在哈纳基区地衣研究的基础上,主要分析石蕊科,地衣的地理区系成分、生态分类,并对保护区环境保护,发展旅游业,生物资源开发与保护和生物多样生研究提供了科学依据与参考。  相似文献   
8.
利用东方黄梅和犬地卷微核千分率研究环境污染   总被引:1,自引:0,他引:1  
本文通过地衣植物藻类细胞微核检测技术测定了分布于天山菊花台和后峡地区地衣藻类细胞微核千分率(MCN‰)及环境污染指数,并进行了t检查。结果表明(MCN‰)有明显差异。从两个分布区2种地衣细胞观察分析来看,后峡地区地衣藻类细胞的污染指数都在3.5以上,通过t检查也可以看到,差异极度显著所获得的数据表明,后峡区受到严重的污染。  相似文献   
9.
托木尔峰自然保护区地衣的补充研究   总被引:6,自引:0,他引:6  
我们根据多年的研究并结合前人的工作进一步地整理了分布在新疆托木尔峰自然保护区的地衣种类。分析该地区的地衣种有120个,分别隶性于49属,其中有11个变种和4个变型。调查中我们还发现该地区地衣随着海拔高度的升高而有所不同,北坡和南坡也有明显的差异。  相似文献   
10.
The cryopreservation of testicular tissue is a potential method for preserving male fertility. However, the effect of cryopreservation on bovine calf testicular tissue is scarce. This study investigated the effect of different cryoprotectants on bovine calf testicular tissue at the molecular level. Testicular tissue from ten immature bovine calves (6 months) was collected after slaughter and cryopreserved in an extender containing different concentrations of the following five cryopreservation solutions (CP): bovine serum albumin (BSA) with 5% dimethyl sulfoxide (DMSO), trehalose with 5% DMSO, DMSO and glycerol and ethylene glycol (EG). After 7‐day cryopreservation, the expression levels of three spermatogonial stem cell (SSC)‐related genes, octamer‐4 (OCT4), KIT ligand (MGF/SCF) and kit oncogene (C‐KIT), were investigated by quantitative PCR (qPCR). The cell viability was highest for the tissues preserved with 30 mg/ml BSA (77.82% ± 1.22) and 40 mg/ml trehalose (74.23% ± 1.16) compared with other groups (p < 0.05), and the level of expression of the three genes was highest with 30 mg/ml BSA (p < 0.05). Compared with other CPs, the 30 mg/ml BSA and 40 mg/ml trehalose have the better cryopreserve protection. The 30 mg/ml BSA is the most viable media for the cryopreservation of testicular tissue from cattle.  相似文献   
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