不同分离方法及培养方式对绵羊腔前卵泡发育能力的影响

研究的目的在于分析用不同的方法分离绵羊腔前卵泡以及用不同的培养方式对分离得到的腔前卵泡进行培养,对于绵羊腔前卵泡存活和发育能力的影响。实验分两部分进行：实验1为分离卵巢皮质,分别用显微分离法和胶原酶法分离腔前卵泡。实验2是在实验1的基础上,将较优方法获得的腔前卵泡分别进行单独培养和群体培养。结果显示,显微分离法与胶原酶法相比,在获得的腔前卵泡数量上差异不显著,但显微分离法获得的腔前卵泡基膜完整率显著高于胶原酶法（P<0.05）。获得的腔前卵泡使用单独和群体两种方式进行培养,其直径增加值在第三天和第六天差异不显著,但单独培养法在第三天和第六天的存活率显著高于群体培养法（P<0.05）,且有卵泡腔形成。研究显示使用显微分离法分离腔前卵泡与胶原酶法相比具有优势,相对简单,廉价并且对卵泡的损害很小。经显微分离法获得的腔前卵泡,使用单独培养法进行培养能够促进卵泡的生长发育。     

不同培养方法及培养密度对绵羊腔前卵泡发育的影响

通过对绵羊腔前卵泡培养方法的研究,能够探索出适宜绵羊腔前卵泡生长发育的培养条件,以及为进一步揭示绵羊卵泡生长发育的规律奠定一些基础。试验一通过使用微滴法和琼脂培养基法培养腔前卵泡,观察其对绵羊腔前卵泡生长的影响;试验二通过绵羊腔前卵泡单独培养与群体培养,探讨不同培养密度对绵羊腔前卵泡生长的影响。试验结果显示,使用微滴法与琼脂培养基法培养的绵羊腔前卵泡,在培养3天时,卵泡直径增加值和存活率差异均不显著(P0.05);但培养6天时,琼脂培养基法培养的腔前卵泡的直径增加值和存活率均极显著高于微滴法培养的腔前卵泡(P0.01);在使用琼脂培养基培养的条件下,对绵羊腔前卵泡进行单独培养和群体培养,在培养的6天时间内二者卵泡直径增加值和存活率差异均不显著(P0.05)。试验结果表明,琼脂培养基法是较为适宜的绵羊腔前卵泡体外培养方法;培养密度对绵羊腔前卵泡体外培养并无显著影响。     

GDF9与BMP15在绵羊腔前卵泡及卵母细胞体外成熟过程中的差异表达

为了探讨GDF9与BMP15在绵羊腔前卵泡发育及卵母细胞体外成熟过程中的作用,运用腔前卵泡的显微分离方法和RT-PCR技术,检测了GDF9、BMP15 mRNA在绵羊腔前卵泡及卵母细胞体外成熟过程中(0、8、16、24 h)的相对表达丰度。结果表明：绵羊COCs在体外培养的不同时期,卵丘细胞扩展呈现不同的形态学变化;腔前卵泡中GDF9、BMP15 mRNA表达量均低于体外成熟不同时期卵母细胞,且腔前卵泡中GDF9 mRNA表达量显著低于体外成熟不同时期卵母细胞。揭示GDF9和BMP15对卵巢卵泡发育和卵母细胞体外成熟发挥重要作用,在绵羊卵母细胞体外成熟过程中,这2个因子可能是独立或协同地影响卵丘细胞增殖扩散。     

来源和质量不同对山羊卵母细胞体外成熟率的影响

比较了卵母细胞级别对体外成熟率的影响,以及促卵泡素(FSH)处理山羊对卵母细胞采集的数量和质量的影响。结果表明:卵母细胞级别对体外成熟率有显著影响,不论是来源于FSH处理卵巢还是屠宰场卵巢,均是A、B级卵母细胞的成熟率高于C级卵母细胞,差异极显著(P<0.01)。但是A、B级卵母细胞之间差异不显著;卵巢来源对卵母细胞采集的数量和质量有显著影响,A、B级卵母细胞在获卵总数中所占的比例,平均每个卵巢获卵母细胞数及A、B级卵母细胞数,均是FSH处理卵巢高于屠宰场卵巢,差异显著(P<0.05);卵巢来源对卵母细胞体外成熟率有显著影响,来自于FSH处理卵巢的卵母细胞体外成熟率高于屠宰场卵巢(81.6%比67.6%),差异极显著(P<0.01)。     

诱导幼龄绵羊卵泡发育的研究

为了稳定并提高幼龄绵羊卵泡的发育效率。本研究从激素处理方案、激素生产厂家、羔羊日龄、重复处理周期等4个方面进行了研究。结果表明：国产FSH剂量在60IU/只、120 IU和180 IU之间差异显著(P<0.05);国产FSH和加拿大生产的FSH对幼羔卵泡发育没有影响;5－9周龄羔羊的卵泡数和卵母细胞数显著高于4周龄和11周龄的羔羊(P<0.05);4-7周龄羔羊首次处理后间隔15~30天再次处理的卵泡数和卵母细胞数都没有差异(P>0.05),2次重复处理总卵泡数和卵母细胞数间也没有差异(P>0.05)。     

猪腔前卵泡卵母细胞体外成熟培养初探

【研究目的】为了进一步挖掘猪的遗传潜力,为体外受精、动物克隆和转基因等胚胎生物技术研究提供大量优质卵源。【方法】以极体排出情况为判断标准,采用一步法和两步法成熟培养猪腔前卵泡卵母细胞,来考察猪腔前卵泡卵母细胞最佳成熟方式。【结果】采用任何一种方法卵母细胞经体外成熟后都没有达到MⅡ。然而,腔前卵泡体外培养5d后,分离出的卵丘卵母细胞复合体再培养12d,卵母细胞平均直径达到102.68μm(102.68±12.21),接近正常成熟卵母细胞的体积,为卵母细胞的成熟创造了条件。【结论】用两步法培养猪的腔前卵泡,其卵母细胞能够达到接近正常成熟卵母细胞的体积,说明采用两步法培养猪腔前卵泡卵母细胞是可行的。     

AY 9944-A-7对于IBMX抑制的绵羊卵母细胞体外成熟的诱导作用

为了探究AY 9944-A-7在3-异丁基-1-甲基黄嘌呤(3-isobutyl-1-methylxanthine,IBMX)阻滞的绵羊卵母细胞减数分裂恢复过程中的作用,将绵羊卵丘-卵母细胞复合体( COCs)、分离的卵丘-卵母细胞( split COCs)和脱卵丘后制成的裸卵(DOs)培养于含250μmol/L IBMX的体外成熟液中,分别添加10,20,30,40μmol/L的AY 9944-A-7以诱导卵母细胞恢复减数分裂。结果表明,10~40μmol/L 的 AY 9944-A-7极显著地提高了绵羊 COCs 的生发泡破裂(GVBD)率和第一极体(PBI)排出率(P<0.01)；添加AY 9944-A-7对IBMX阻滞的绵羊DOs 生发泡破裂和PBI排出没有显著的刺激作用(P>0.05)；40μmol/L AY 9944-A-7使绵羊COCs、split COCs、DOs的退化率极显著提高(P<0．01)。说明AY 9944-A-7能够诱导IBMX抑制的绵羊COCs恢复减数分裂成熟,但是过量的AY 9944-A-7对绵羊卵母细胞有毒性,AY 9944-A-7诱导绵羊COCs克服IBMX抑制恢复减数分裂成熟的适宜剂量为20μmol/L。     

不同诱导剂对山羊精子体外获能和受精能力的影响

比较不同获能诱导剂对山羊精子体外获能及受精能力的影响,优化山羊早期胚胎体外生产技术体系。山羊精子分别以不同浓度肝素、IA和EGS处理后,检查精子获能率、活力和体外存活时间,同时与体外成熟的卵母细胞受精,观察不同获能处理对精子受精能力的影响。在培养液中添加5,10,20μg／mL肝素,都能促进精子获能,其中10μg／mL组的获能率达到55．6％,存活时间为18～19h;低于此浓度,获能率显著降低,高于此浓度,获能率升高不显著,但精子存活时间和活力明显下降。0．1,0．4,0．7μmol／LIA都能提高精子获能率,其中0．4和0．7μmol／L处理组精子获能率最高,分别为56．2％和53．6％,但两组中的精子活力和存活时间有明显差异。5％,10％和20％EGS都能提高精子活力,延长体外存活时间,但实验组的获能率最高不到20％。10％EGS获能组的受精率和卵裂率分别为27．9％和18．6％,显著低于10μg／mL肝素和0．4μmol／L IA组,后两者的受精率相似,但IA组的卵裂率明显高于肝素组（52．0％VS40．2％,P〈0．05）。10μg／mL肝素和0．4μmol／L IA都可诱导山羊精子高水平获能,并获得较好的受精能力,但IA表现出更强的促卵裂发生效应。     

绵羊对4种蛋白饲料日粮营养物质消化动态变化的比较

试验采用3头35 kg左右的美利奴绵羊研究不同蛋白饲料日粮对绵羊营养物质消化的影响。为自身对照试验设计,整个试验分4期进行,每期3头羊饲喂同一种蛋白饲料日粮。4种蛋白来源分别为棉籽粕、大豆粕、葵粕和菜籽粕。试验结果表明:绵羊采食蛋白来源为棉籽粕的日粮时,干物质、有机物和氮采食量最高,而菜籽粕采食量最低。饲喂棉籽粕日粮,干物质、有机物和纤维素十二指肠流量显著高于大豆粕日粮和菜籽粕日粮(P<0.05)。大豆粕日粮粗蛋白在前胃的消失率最高为33%,其余3组日粮粗蛋白前胃的降解率为16%~20%。到达小肠的菌体蛋白(MCP)量各组间无差异,而到达小肠过瘤胃饲料蛋白的量(率)棉籽粕组显著高于葵粕组、菜籽粕组、大豆粕组。大豆粕组粗蛋白在小肠的表观消化率最低为48%,其余3组日粮粗蛋白小肠表观降解率均为66%。     

中国牛冷冻精液质量性状的评估与分析

为进一步提高牛冷冻精液的质量与探索技术关键,本研究对近年来国内各牛冷冻精液生产企业1720头份精液样品进行了质量分析,涉及品种有奶牛、肉牛类(包括乳肉兼用、黄牛、牦牛等)和奶水牛等。结果表明:剂量值(0.20±0.008)mL、活力(40.9±2.3)%、每剂量前进运动精子数(1224.3±291.7)万个、畸形率(12.6±3.8)%、细菌菌落数(38.9±192.7)个。年度间比较,活力呈不规则的起伏变化;2016年畸形率均值显著低于前2个年度,分别下降0.8%和1.3%,3个年度间均差异显著(P0.05),2014年细菌菌落数显著高于其他2个年度(P0.05);品种间比较,奶牛活力高于奶水牛0.5%、高于肉、兼用牛0.2%(P0.05),奶水牛与肉牛及兼用牛之间差异不显著(P0.05),奶水牛畸形率分别高于奶牛1.9%、高于肉用牛0.9%,均差异显著(P0.05),前进运动精子数,奶水牛最高,奶牛最低,品种间均差异显著(P0.05);生产企业间比较,活力、前进运动精子数、畸形率均分别存在不同差异。     

Biological Activity and Quantification of Suspected Allelochemicals from Alfalfa Plant Parts

Autotoxicity restricts reseeding of alfalfa (Medicago sativa L.) after alfalfa until autotoxic chemical(s) breaks down or is dispersed into external environments. A series of aqueous extracts from leaves, stems, roots and seeds of alfalfa ‘Vernal’ were bioassayed against alfalfa seedlings of the same cultivar to determine their autotoxicity. The highest inhibition was found in the extracts from the leaves. Extracts at 40 g dry tissue l^?1 from alfalfa leaves were 15.4, 17.5 and 28.7 times more toxic to alfalfa root growth than were those from roots, stems and seeds, respectively. A high‐performance liquid chromatography (HPLC) analysis with nine standard compounds showed that the concentrations and compositions of allelopathic compounds depended on the plant parts. In leaf extracts that showed the most inhibitory effect on root growth, the highest amounts of allelochemicals were detected. Among nine phenolic compounds assayed for their phytotoxicity on root growth of alfalfa, coumarin, trans‐cinnamic acid and o‐coumaric acid at 10^?3 m were most inhibitory. The type and amount of causative allelochemicals found in alfalfa plant parts were highly correlated with the results of the bioassay, indicating that the autotoxic effects of alfalfa plant parts significantly differed.     

Changes in Seed Yield and Quality with Maturity in Onion (Allium cepa L., cv. 'Early Cream Gold')

Development of onion (Allium cepa L., cv. ‘Early Cream Gold’) seed under cool climate conditions in Tasmania, Australia occurred over a longer duration than previously reported, but similar patterns of change in yield components were recorded. In contrast to previous studies, umbel moisture content declined from 85 to 67 % over 57 days while seed moisture content decreased from 85 to 31 %. Seed yield continued to increase over the duration of crop development, with increasing seed weight compensating for seed loss resulting from capsule dehiscence in the later stages of maturation. Germination percentage was high and did not vary significantly from 53 to 77 days after full bloom (DAF), but mean germination time declined and uniformity of germination increased significantly over the same time period. The percentage abnormal seedlings declined with later harvest date, resulting in highest seed quality at 77 DAF. The results of this study suggest that the decision to harvest cool climate onion seed crops before capsule dehiscence will result in a loss of potential seed yield and quality.     

Location of a high-lysine gene and the DDT-resistance gene on barley chromosome 7

Summary The high-lysine gene in Risø mutant 1508 conditions an increased lysine content in the endosperm via a changed protein composition, a decreased seed size, and several other characters of the seed. The designation lys3a, lys3b, and lys3c, is proposed for the allelic high-lysine genes in three Risø mutants, nos 1508, 18, and 19. Linkage studies with translocations locate the lys3 locus in the centromere region of chromosome 7. A linkage study involving the loci lys3 and ddt (resistance to DDT) together with the marker loci fs (fragile stem), s (short rachilla hairs), and r (smooth awn) show that the order of the five loci on chromosome 7 from the long to the short chromosome arm is r, s, fs, lys3, ddt. The distance from locus r to locus ddt is about 100 centimorgans.     

Simultaneous Determination of Four Phenolic Acids in Radix Salviae Miltiorrhizae Formula Granules by QAMS

[Objectives]This study aimed to establish a QAMS(quantitative analysis of multi-components by single-marker)method for simultaneous determination of four phenol...     

Water Extraction Process of Chinese Herbal Compound Man Gan Ning

[Objectives]To optimize the water extraction process of Chinese Herbal Compound Man Gan Ning and establish a method for its extraction and content determination...     

Present status and future strategy in breeding faba beans (Vicia Faba L.) for resistance to biotic and abiotic stresses

Progress is being made, mainly by ICARDA but also elsewhere, in breeding for resistance to Botrytis, AScochyta, Uromyces, and Orobanche; and some lines have resistance to more than one pathogen. The strategy is to extend multiple resistance but also to seek new and durable forms of resistance. Internationally coordinated programs are needed to maintain the momentum of this work.Tolerance of abiotic stresses leads to types suited to dry or cold environments rather than broad adaptability, but in this cross-pollinated species, the more hybrid vigor expressed by a cultivar, the more it is likely to tolerate various stresses.     

Pollen and pollination experiments. III. The viability of apple and pear pollen as affected by irradiation and storage

Summary Apple and pear pollen was irradiated with doses of 0, 50, 100, 250 and 500 krad (gamma rays) and stored at 4°C and 0–10% r.h. From the in-vitro germination percentages an average LD 50 dose of about 220 krad was estimated. For both irradiated and untreated pollen a close and corresponding lineair relationship existed between germination percentage and pollen tube growth.Irradiated pollen was much more sensitive to dry storage conditions than untreated pollen, resulting in less germination and more bursting. Apparently, irradiation caused the pollen cell membrane to lose its flexibility faster than normal. Rehydration of dry-stored, irradiated pollen in water-saturated air restored germination percentages up to their initial levels. The importance of this procedure in germination trials is stressed.     

Optimization of Extraction Technology and Determination of Content of Total Phenols of Leaves in Acanthopanax giraldii Harms

[Objectives] To determine the optimum extraction technology for total phenols of leaves in Acanthopanax giraldii Harms.[Methods]The single factor test and ortho...     

Cytoplasmic male sterility,resistance to gall mite and mildew,and season of leafing out in black currants

Summary Cytoplasmic male sterility (cms) is described in the F₁ hybrids Ribes × carrierei (R. glutinosum albidum × R. nigrum) and R. sanguineum × R. nigrum. In backcrosses to R. nigrum, progenies with R. glutinosum cytoplasm were either all male sterile, or segregated for full male fertility (F) and complete (S) and partial (I) male sterility. Ratios of F:I+S suggested that two linked genes controlled cms, F plants being dominant for one (Rf ₁) and recessive for the other (Rf ₂).Segregation for cms in relation to three linded genes, Ce (resistance to the gall mite, Cecidophyopsis ribes), Sph ₃(resistance to American gooseberry mildew, Sphaerotheca mors-uvae) and Lf ₁(one of two dominant additive genes controlling early season leafing out) indicated that Rf ₁and Rf ₂were in this linkage group. The gene order and approximate crossover values appeared to be: % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXafv3ySLgzGmvETj2BSbqef0uAJj3BZ9Mz0bYu% H52CGmvzYLMzaerbd9wDYLwzYbItLDharqqr1ngBPrgifHhDYfgasa% acOqpw0xe9v8qqaqFD0xXdHaVhbbf9v8qqaqFr0xc9pk0xbba9q8Wq% Ffea0-yr0RYxir-Jbba9q8aq0-yq-He9q8qqQ8frFve9Fve9Ff0dme% aabaqaciGacaGaamqadaabaeaafaaakeaacaWGdbGaamyzamaamaaa% baGaaiiiaiaacccacaGGWaGaaiOlaiaacgdacaGG0aGaaiiiaiaacc% caaaGaaiiiaiaacccacaGGGaGaamOuaiaadAgaliaaigdakmaamaaa% baGaaiiiaiaacccacaGGGaGaaiiiaiaaccdacaGGUaGaaiOmaiaacs% dacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaaaacaWGsbGaamOzaSGa% aGOmaOWaaWaaaeaacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaiaacc% cacaGGGaGaaiiiaiaacccaaaGaamitaiaadAgaliaaigdakmaamaaa% baGaaiiiaiaacccacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaiaacc% cacaGGGaGaaiiiaiaacccacaGGGaaaaiaadofacaWGWbGaamiAaSGa% aG4maaaa!6E4D!\[Ce\underline { 0.14 } Rf1\underline { 0.24 } Rf2\underline { } Lf1\underline { } Sph3\]. Crossover values of 0.36 for Ce-Lf ₁, and 0.15 for Lf ₁-Sph ₃were estimated from the relative mean differences in season of leafing out between seedlings dominant and recessive for Ce and Sph ₃.It is suggested that competitive disadvantage of lf ₁-carrying gametes and/or zygotes at low temperatures may be implicated in the almost invariable deficit of plants dominant for the closely linked mildew resistance allele Sph ₃. Poor performance of lf ₁- (and possibly lf ₂-) carrying gametes and young zygotes during periods of low temperature at flowering might also account for the liability of some late season cultivars and selections to premature fruit drop (running off).     

Screening techniques and sources of resistance to parasitic angiosperms

Parasitic angiosperms cause great losses in many important crops under different climatic conditions and soil types. The most widespread and important parasitic angiosperms belong to the genera Orobanche, Striga, and Cuscuta. The most important economical hosts belong to the Poaceae, Asteraceae, Solanaceae, Cucurbitaceae, and Fabaceae. Although some resistant cultivars have been identified in several crops, great gaps exist in our knowledge of the parasites and the genetic basis of the resistance, as well as the availability of in vitro screening techniques. Screening techniques are based on reactions of the host root or foliage. In vitro or greenhouse screening methods based on the reaction of root and/or foliar tissues are usually superior to field screenings and can be used with many species. To utilize them in plant breeding, it is necessary to demonstrate a strong correlation between in vitro and field data. The correlation should be calculated for every environment in which selection is practiced. Using biochemical analysis as a screening technique has had limited success. The reason seems to be the complex host-parasite interactions which lead to germination, rhizotropism, infection, and growth of the parasite. Germination results from chemicals produced by the host. Resistance is only available in a small group of crops. Resistance has been found in cultivated, primitive and wild forms, depending on the specific host-parasite system. An additional problem is the existence of pathotypes in the parasites. Inheritance of host resistance is usually polygenic and its transfer is slow and tedious. Molecular techniques have yet to be used to locate resistance to parasitic angiosperms. While intensifying the search for genes that control resistance to specific parasitic angiosperms, the best strategy to screen for resistance is to improve the already existing in vitro or greenhouse screening techniques.