牛胚胎玻璃化冷冻技术研究进展

胚胎冷冻保存是保存和繁殖遗传优势动物的主要工具,是胚胎移植产业的重要组成部分。目前广泛使用的冷冻方法主要有慢速冷冻和玻璃化冷冻2种。由于玻璃化冷冻具有成本低、效率高、操作简单等优点,玻璃化冷冻法越来越受到人们的重视。经过多年研究,研究人员已经在玻璃化冷冻方法、冷冻液等方面取得了大量进展,玻璃化冷冻法已经开始进入商业化应用。本文综述了牛胚胎冷冻保存技术的研究进展,旨在为相关从业人员提供一定借鉴和参考。     

NaCl处理对4种牧草植物种子萌发的影响

为探究草木樨（Melilotus suaveolens Ledeb.）、沙打旺（Astragalus adsurgens Pall.）、沙米（Agriophyllum squarrosum（Linn.）Moq.）、蒙古冰草（Agropyron mongolicum Keng）4种牧草种子在不同浓度NaCl处理下的萌发情况,本试验采用50 mmol·L^-1,100 mmol·L^-1,150 mmol·L^-1,200 mmol·L^-1,300 mmol·L^-15种NaCl浓度处理这4种牧草种子,测定其种子的发芽率、发芽指数等。结果表明：低浓度NaCl（50 mmol·L^-1和100 mmol·L^-1）处理对草木樨和沙打旺种子的发芽率、发芽势、发芽指数、活力指数的影响不显著,但对沙米和蒙古冰草种子的发芽有显著抑制作用;当NaCl浓度达到150 mmol·L^-1和300 mmol·L^-1时,沙米和蒙古冰草种子均不能发芽;4种牧草种子对NaCl的耐受程度由强到弱的顺序为：草木樨、沙打旺、蒙古冰草、沙米。     

五种草坪草对水涝胁迫的反应及耐涝评价

以沟叶结缕草(Zoysia matrella(L.)Merr.)、大穗结缕草(Z.macrostachya Franch.et Sav.)、普通狗牙根(Cynodon dactylon(L.)Pers.)、青岛结缕草(Z.japonicacv QingDao)和高羊茅品种翠碧(Festuca arundinacea cv Triplet)为材料,对其在水涝胁迫下草坪草形态、生理指标变化进行了研究,并采用隶属函数法对其耐涝性进行评价,以期为江南中下游地区草坪草的栽培提供试验依据。结果表明:随水涝时间的延长,叶片枯黄率逐渐增加,叶片相对电导率(REC)、超氧化物歧化酶(SOD)和过氧化物酶(POD)活性以及游离脯氨酸(Pro)和可溶性总糖(TSC)含量5个生理指标在水胁迫15 d时均比对照明显增加;以REC,SOD和POD活性以及Pro和TSC含量为指标,对5个草种的耐涝隶属函数值进行计算,并对其耐涝适应性进行综合评价,得出5个草种的耐涝性顺序为大穗结缕草>普通狗牙根>翠碧>青岛结缕草>沟叶结缕草。     

盐碱复合胁迫对白茎盐生草种子萌发的影响

为了解盐碱胁迫对种子萌发的影响,本研究以白茎盐生草(Halogeton arachnoideus)为研究对象,采用室内模拟试验,以盐分种类和盐浓度为控制因素,按照NaCl?Na2SO4?NaHCO3?Na2CO3的顺序,以A(1?1?0?0)、B(1?2?1?0)、C(1?9?9?1)、D(1?1?1?1)、E(9?1...     

Cryopreservation of ram semen: Manual versus programmable freezing and different lengths of equilibration

The aim of our study was to examine effects of the length of semen equilibration as well as two freezing techniques on ram sperm post-thaw quality. The ejaculates of Wallachian sheep rams (n = 12) were collected by an electro-ejaculation, equilibrated in a Triladyl® (0, 2, 4, 6, and 8 h) containing glycerol and egg yolk and frozen by programmable freezing (PF) or manual freezing (MF). After thawing, sperm samples were subjected to the motility (computer-assisted sperm analysis [CASA]), viability (SYBR-14/PI), and fertilizing ability (FA) (in vitro penetration/fertilization test on bovine oocytes) assays. It was found that the equilibration of 6 h (E-6) ensured higher post-thaw sperm motility and progressive movement compared with other lengths tested, irrespective of a freezing technique. The E-6 sperm viability did not differ between PF and MF but was lower (P < 0.05) than control. Sperm FA (E-6) was similar in PF (60.44%) and MF (62%) but slightly lower than in fresh (72.8%). Our data demonstrate that the use of MF was comparable with PF, which can be applied in the field conditions without need in a piece of cost-expensive equipment, which can greatly benefit the gene bank of animal genetic resources.     

Fumonisin B1 Metabolism by Bovine Liver Microsomes

Only limited and contrasting information is available about the metabolic fate in cattle of fumonisin B₁, a mycotoxin produced by moulds of Fusarium. This study was carried out to evaluate the hepatic metabolism of fumonisin B₁ by bovine liver microsomes. No biodegradation or metabolization of the mycotoxin by liver microsomes was detectable after incubating fumonisin B₁ with bovine microsomes in the presence of a regenerating system for 1 h. No aminopolyol 1, aminopolyol 2 or aminopentol, metabolites of fumonisin B₁, were detected in any of the incubated samples. The tolerance of ruminants to fumonisin B₁ is apparently not dependent on its detoxification in the rumen.     

Is sperm cryopreservation in absence of permeable cryoprotectants suitable for subfertile donkeys?

Sperm from fertile donkeys have been successfully frozen in absence of permeable cryoprotectants. The aim of this study was to determine whether this cryopreservation method is suitable for subfertile donkeys in comparison to conventional sperm freezing with glycerol. Ejaculates were collected from four Andalusian Donkeys: three fertile and one subfertile. Semen was frozen with an extender containing glycerol (GLY), or adding instead sucrose 0.25 molar and 1% bovine serum albumin (SUC) as non‐permeable cryoprotectants. After thawing, samples were assessed for total (TM, %) and progressive (PM, %) sperm motility by CASA, plasma membrane integrity (PMI, %) by epifluorescence microscopy and DNA integrity (DFI, %) by SCSA. Results (mean ± SD) were compared between extenders in fertile and subfertile donkeys using the Student's t test. No differences between GLY and SUC treatments were found in the fertile group for the sperm parameters assessed. In subfertile donkey ejaculates, GLY resulted in significantly higher values than SUC for TM (25.5 ± 3.1 vs. 19.6 ± 1.9) and PM (13.3 ± 5.1 vs. 4.0 ± 1.2), respectively. In conclusion, considering all the sperm parameters assessed, sperm freezing in absence of permeable cryoprotectants may not be still an option for cryopreservation of subfertile donkey sperm.     

超级稻两优培九生育后期的光能利用和同化产物分配

以籼、粳亚种间杂交稻两优培九及其父本93ll为材料,测定了光合速率、叶绿素荧光参数及^14CO2同化产物分配的指标。结果表明：在生育后期,与父本93ll相比,两优培九具有较高的光合能力;在中午强光的逆境条件下,原初光化学效率(Fv／Fm)、光化学猝灭系数(qP)和PSⅡ在照光下的实际光化学效率(ΦPSⅡ)的下降相对较少,具有较强的耐光抑制能力;用同位素^14C对光合同化产物运转分配进行标记研究,发现两优培九光合同化产物向穗部的分配比率较高,具有较好的源库协调性。上述有关光合和同化产物的分配特点可能是超级稻高产的生理基础。     

不同月季品种耐阴性比较研究

以8个月季品种为试验材料,进行透光率25%、50%、75%和100%的遮阴处理,测定了其脯氨酸、可溶性糖、叶片相对含水量、叶绿素和可溶性蛋白含量。结果表明:8个月季品种在不同透光条件下耐阴程度有所不同,同一品种在不同透光处理下各项生理指标的反应也不尽完全相同,多数品种在遮阴胁迫后叶片脯氨酸含量、可溶性总糖、叶片相对含水量、叶绿素和可溶性蛋白含量均与ck有极显著差异(P<0.01),但各品种间差异有所不同,在透光率25%条件下,白米浓表现最好,各项指标均与ck有极显著差异(P<0.01)。通过对8个月季品种的综合分析得出,耐阴性强弱顺序依次为:白米浓(可在透光率25%的条件下生长)>玫瑰地毯、恋情火焰、猩红梅荻郎和紫微星(可在透光率50%的条件下生长)>哈德福俊(可在透光率75%的条件下生长)>巴西诺和皇家巴西诺(只在全光照条件下生长)。     

结缕草耐盐分离群体的构建

为进一步研究结缕草属(Zoysia Willd.)植物的耐盐性遗传机制,通过结缕草耐盐亲本Z105(Z.japonica)和敏盐亲本Z061(Z.japonica)进行人工杂交,以构建结缕草的耐盐分离群体.首先通过SRAP(Sequence-relatedamplified polymorphism)分子标记技术对所获得的F1群体杂种真实性进行鉴定,在此基础上,通过水培法对F1群体的耐盐性进行鉴定.结果表明:F1群体164个后代中132个后代为真杂种,这些后代的耐盐性表现出连续性的遗传变异,存在明显的分离现象,成功地构建了结缕草的耐盐性分离群体.这为结缕草耐盐性的遗传分析、遗传图谱的构建和耐盐