牦牛卵母细胞的体外成熟

以屠宰场牦牛卵巢为材料,比较了抽吸加切割法和抽吸法2种卵母细胞离体采集方法的效率和5种成熟培养液的培养效果,并研究了卵泡位置、形态对卵母细胞体外成熟的影响。结果表明:在牦牛乏情期,平均每个卵巢用抽吸加切割法回收卵数极显著高于抽吸法(9.33±4.30VS4.70±2.62,P<0.01),可用卵数也极显著高于抽吸法(5.63±4.19VS4.37±2.32,P<0.01)。将牦牛卵丘卵母细胞复合体(COCs)分别置于5种成熟培养液中培养,其中M199(缓冲体系为Earles盐) 10% FBS 5.0mg/LLH 1.0mg/LE2 双抗(青霉素100IU/mL和链霉素100mg/L)的成熟液效果最好,成熟率为81.33%,卵裂率为49.33%。来自卵巢表面卵泡的COCs的成熟率和卵裂率均高于来自卵巢内卵泡的COCs(分别为81.33%VS69.33%,P>0.05;49.33%VS34.67%,P<0.05)。来自明亮卵泡的COCs的成熟率和卵裂率均极显著高于来自浑浊卵泡的COCs(分别为81.33%VS33.33%,P<0.01;49.33%VS3.33%,P<0.01)。     

生长激素对体外培养猪COCs影响的研究

研究了生长激素对猪COCs体外成熟过程中卵丘细胞扩展、卵丘细胞凋亡、卵母成熟及孤雌激活后卵裂的影响。结果表明:生长激素(STH)能够促进卵丘细胞扩展,抑制卵丘细胞凋亡,对卵母细胞的成熟和激活后卵裂呈现双重效应。在猪COCs培养液中添加0.15μg/mL STH成熟率(73.83%±1.80%)和卵裂率(64.76%±2.84%)显著高于对照组(mNCSU-23+PMSG(10IU/mL)+hCG(10 IU/mL))及添加0.01、0.05、0.1、2μg/mL STH组(P<0.05),在本实验中为猪卵母细胞体外成熟的最佳条件。     

山羊卵母细胞体外成熟培养液体积筛选

研究在一定卵丘-卵母细胞复合体(COCs)与培养液体积比例条件下,不同体积的培养液对山羊卵母细胞体外成熟的影响。按照COCs 1枚/4μL培养液的比例,采用5种不同体积的培养液,即50,100,250,500和1 000μL,对山羊卵母细胞进行体外成熟培养和孤雌激活。结果:100μL和250μL两组的卵母细胞体外成熟培养24 h后,其卵母细胞成熟率分别为78.10%和74.62%,差异不显著(P>0.05),但高于50μL组(P<0.05)、500μL组(P<0.05)和1 000μL组(P<0.01)组。100μL组孤雌激活胚胎的卵裂率(68.37%)、桑葚胚率(48.78%)和囊胚率(27.61%)都优于其他各组,其卵裂率和囊胚率与250μL组相比差异不显著(P>0.05)。结果表明采用COCs 1枚/4μL培养液的比例条件下培养卵母细胞,宜选用100～250μL范围内的培养液体积进行卵母细胞成熟培养,其卵母细胞体外成熟率可以达到78.10%左右。     

牦牛卵母细胞的体外成熟、种间受精与胚胎培养

探讨了卵母细胞体外成熟时间、卵母细胞质量、精子准备和受精卵培养体系对牦牛卵母细胞种间体外受精效果的影响。结果表明:牦牛卵母细胞随体外成熟培养时间延长,第一极体排出率增加,囊胚发育率以成熟培养24 h最高;A级卵母细胞种间受精后囊胚的发育率(48.77±3.76)%显著高于B级(32.05±5.24)%和C级(7.54±7.18)%(P<0.05);BO液洗涤离心处理的精子受精后卵裂率(82.53±6.54)%显著高于Percoll液分离精子受精后的卵裂率(67.39±4.50)%(P<0.05),而两者囊胚率差异不显著((42.32±4.13)%vs(35.59±5.62)%,P>0.05);荷斯坦奶牛精子浓度在1×106～5×106/mL范围与牦牛卵母细胞受精效果差异不显著。卵丘细胞、输卵管上皮细胞共培养和SOF液培养种间受精卵,其卵裂率差异不显著,但共培养组的桑葚胚、囊胚和孵化胚发育率均显著高于SOF液培养组。     

卵丘细胞对辽宁绒山羊卵母细胞体外成熟与孤雌发育的影响

为了进一步探索辽宁绒山羊卵母细胞体外成熟的方法,本试验以屠宰场绒山羊卵巢为材料,采用抽吸法收集直径大于2 mm卵泡的卵母细胞,研究卵丘细胞对卵母细胞体外成熟和孤雌发育的影响。试验1,将一部分COCs经机械吹打脱除卵丘细胞成为机械裸卵(DOs),然后以4种方式培养,即COCs单独培养、DOs与COCs共培养(DOs(COCs))、DOs与卵丘颗粒细胞共培养(DOs(CCs)),以及DOs单独培养。试验2,根据包裹卵母细胞的卵丘细胞的完整性分为3组,有3层卵丘细胞紧密包围的卵母细胞复合体COCs3,有1-3层卵丘细胞包围的卵母细胞COCs1-3,无卵丘细胞包围的裸露卵母细胞NOs,3组各自单独培养。结果表明:COCs组的成熟率、孤雌卵裂率和囊胚率最高,分别为83.25%、41.75%和29.25%,卵丘细胞的存在有利于卵母细胞体外成熟和随后的发育,COCs3组成熟率、孤雌卵裂率和囊胚率分别为83.25%、42.50%和29.75%,显著高于COCs1-3和NOs组,卵丘细胞的完整性也影响着卵母细胞的体外发育,自然裸卵已失去体外发育能力。     

卵泡大小和颗粒细胞对山羊卵泡卵母细胞体外成熟和体外受精的影响

用切割法采集卵泡液,收集卵丘一卵母细胞复合体（Cumulus oocytes comlexs,COCs）和自然裸卵,将部分COCs去除卵丘细胞获得机械裸卵,COCs放入体外成熟培养液中培养为成熟卵母细胞,加入获能的精子液,进行体外受精。结果表明：卵母细胞的体外成熟率和卵裂率与卵泡直径密切相关,大卵泡（80．95％,P〈0．01）和中等卵泡（75．50％,P〈0．05）的卵母细胞成熟率高于小卵泡（50．27％）;犬卯泡（53．53％）和中等卵泡（47．13％）的卵裂率显著高于小卵泡的32．26％（P〈0．05）。COCs、机械裸卵和自然裸卵的体外成熟率分别为75．0％、54．2％和10．5％,差异极显著（P〈0．01）,卵裂率分别为53．8％、10．8％和0％,差异极显著（P〈0．01）。对照组和1×10^5、1×10^6个／mL颗粒细胞组卵母细胞体外成熟率分别为68．6％、69．6％和67．8％,无显著差异（P〉0．05）,但均显著高于1×10^7个／mL（51．5％,P〈0．05）和1×10^10个／mL（35．5％,P〈0．05）颗粒细胞组,但各组间的体外受精率无显著差异（P〉0．05）。结果提示,大卵泡和中卵泡的卵母细胞的体外成熟率和卵裂率显著高于小卵泡,体外成熟培养液中添加高浓度的颗粒细胞能显著抑制卵母细胞的体外成熟。     

输卵管和颗粒细胞单层对牛体外受精胚胎发育的影响

以屠宰场牛卵巢为试验材料,研究输卵管细胞单层(OCM)和颗粒细胞单层(GCM)对牛卵母细胞体外成熟(IVM)、体外受精(IVF)和体外培养(IVC)后胚胎发育能力的影响。(1)从卵泡抽取卵丘卵母细胞复合体(COCs),并根据卵母细胞外面卵丘细胞的层数将其分为3类:1级(≥4层);2级(2～3层);3级(0～1层)。作分别在IVM和IVC培养液中添加GCM(1×106个/mL)与不添加的对比试验。结果显示:添加GCM对1级卵母细胞的卵裂率、6～8细胞发育率和囊胚率无明显影响(P>0.05);但添加GCM的2级、3级卵母细胞,受精后的卵裂率、6～8细胞发育率和囊胚率分别高于未添加组(P<0.05)。(2)所有卵母细胞(包括COCs和裸卵)被随机分为3个组,在其IVM和IVC培养液中分别添加OCM、GCM或不添加体细胞(对照组)。结果显示:OCM和GCM组的卵裂率、6～8细胞发育率和囊胚率均高于对照组(P<0.05),而两试验组之间差异不显著。     

玻璃化冷冻对牦牛未成熟卵母细胞发育能力及COC转录组的影响

旨在探讨玻璃化冷冻-解冻对牦牛未成熟卵母细胞发育能力及卵丘-卵母细胞复合体(COCs)转录组的影响,为完善牦牛COCs冷冻保存技术提供理论依据。本研究将未经成熟培养的牦牛COCs进行玻璃化冷冻-解冻后分为2组,A组:COCs体外成熟(IVM)后用普通牛精子进行体外受精(IVF),获得的受精卵在G-1胚胎培养液中培养72 h后转入G-2培养液培养96 h;B组:IVF后,受精卵在G-1培养液培养120 h后转入G-2培养液培养48 h;以未进行冷冻处理的新鲜COCs作为对照组(C组):IVF后,受精卵在G-1培养液培养72 h后转入G-2培养液培养96 h。对牦牛新鲜COCs(n=3)和玻璃化冷冻-解冻的COCs(n=3)进行扩增、建库和转录组测序(RNA-seq)分析。结果发现,B组的卵裂率、囊胚率显著高于A组(P0.05),但A组和B组的卵裂率、囊胚率均显著低于C组(P0.05)。以|log_2(fold change)|≥2,Q0.05为阈值,牦牛冻融COCs相对于新鲜COCs共筛选出851个差异表达基因(DEGs),其中上调846个,下调5个。GO分析表明,DEGs主要富集于生物过程、细胞组分和分子功能3大类;KEGG注释结果表明,DEGs富集到258条通路,其中16条通路显著富集(P0.05)。研究表明,IVF后在G-1培养液中培养120 h可以提高牦牛玻璃化冷冻卵母细胞的后续发育能力;玻璃化冷冻影响牦牛COCs转录组,从而降低卵母细胞的发育潜力。该发现为完善牦牛COCs玻璃化冷冻技术提供了一定的理论基础。     

BCB和Zebularine对绵羊体细胞核移植胚胎发育效果的影响

为探究亮甲酚蓝(BCB)染色选择的卵母细胞是否有利于体细胞核移植胚胎的体外发育,本实验将卵丘-卵母细胞复合体(COCs)放入含有BCB的PBS中染色,根据细胞质颜色可将卵母细胞分成BCB~+组和BCB~-组,并以未经BCB处理的COCs作为对照组,然后将卵母细胞进行体外成熟,统计卵母细胞的成熟率。将成熟后的卵母细胞进行体细胞核移植,其中,部分BCB~+组卵母细胞所需的供体细胞利用Zebularine处理,统计体细胞核移植的卵裂率、桑椹胚率和囊胚率。结果表明:BCB~+组卵母细胞的成熟率显著高于对照组和BCB~-组(71.15%vs 65.38%,53.52%,P0.05);BCB~+组核移植胚胎的卵裂率(87.91%vs 56.83%)、桑椹胚率(37.41%vs 21.73%)和囊胚率(21.48%vs6.82%)均显著高于BCB~-组(P0.05);与对照组相比,BCB~+组卵裂率(87.91%vs 83.23%)和囊胚率(21.48%vs14.89%)也显著升高(P0.05)。BCB~+组供体细胞经Zebularine处理后,胚胎发育能力进一步提高,其中囊胚率显著高于BCB~+组、对照组和BCB~-组(29.25%vs 21.48%,14.89%,6.82%,P0.05)。     

卵丘细胞对猪卵母细胞成熟及发育的影响

本实验旨在研究有无卵丘细胞对卵母细胞成熟及其胚胎发育能力的影响。实验分别设裸卵组、卵丘细胞与卵母细胞共培养组、卵丘-卵母细胞复合体(COCs)组(对照组),检测猪成熟卵母细胞的存活率、极体率、孤雌激活后的卵裂率、囊胚率及各组卵母细胞的谷胱甘肽合成相关基因的表达。结果表明:COCs组卵母细胞经体外培养42 h后其存活率最高(95.76%),高于裸卵组(P<0.05)和共培养组(P>0.05);COCs组第一极体排出率为71.77%,高于共培养组和裸卵组(P<0.05);COCs组在后期发育中卵裂率与囊胚率高于共培养组和裸卵组(P<0.05),而共培养组的卵裂率及囊胚率高于裸卵组(P<0.05);与COCs组相比,裸卵组显著下调了GCLM、GCLC的表达(P<0.05),共培养组中GCLM的表达与COCs组无显著差异。研究结果显示,卵丘细胞对卵母细胞的成熟及发育均有显著影响,在卵母细胞成熟过程中,卵母细胞与卵丘细胞的缝隙连接受损会对卵母细胞的成熟效率产生影响,并且在卵母细胞后期发育中,缝隙连接的完整性与否会影响后期发育能力,并可推论出随着卵丘细胞的减少和缝隙连接的破坏,会造成谷胱甘肽合成基因表达降低,从而影响卵母细胞内的谷胱甘肽合成。     

Influence of follicle size,methods of retrieval on oocytes yield and morphology in Egyptian Jennies ovaries with special reference to maturation rate in vitro

This work was designed to evaluate the ovarian follicular development, oocytes morphology, methods of oocytes reterival, and the effect of different in vitro maturation (IVM) media on cumulus cell expansion and nuclear maturation of Jennies oocytes. Experiment 1, the number of small (<6 mm), medium (6 to 9 mm) and large size (>10 mm) ovarian follicles was recorded. Cumulus-oocyte-complexes (COCs) were reterived and classified into 4 Grades based on their cumulus-cells investment and the homogenous of the ooplasm. In Experiment 2, COCs were recovered by using 18-G, 20-G needle or slicing and scraping of ovarian follicles to determine the number and morphology of the recovered COCs. In Experiment 3, Grade A and B COCs were IVM in DMEM-HG, DMEM-LG, DMEM-F12, TCM199, TCM199-F12 or CR1aa media supplemented with 10 % FCS?+?10 μg FSH/mL?+?10 IU hCG/mL?+?50 μg/mL gentamicin. Maturation was performed for 36 h at 38.5 °C under 5 % CO₂ in humidified air. After IVM, cumulus cell expansion and oocytes nuclear canfiguration were determined. An average of 6.40?±?0.26 follicles was recorded per Jenny ovary, representing 3.37?±?0.46, 1.89?±?0.14 and 1.14?±?0.16, for the small, medium and large size follicles, respectively. Oocyte recovery was higher (P?P?P?P?P?P?P?P?Conclusion: Slicing and scraping or aspiration of follicles using 18-G needle increased the number and percentage of Grade A Jennies oocytes. TCM199-F12, CR1aa and TCM199 medi are more suitable for IVM of Jenny oocytes by promoting cumulus cells expansion and nuclear maturation to M II stage.     

培养介质、卵丘细胞和卵泡直径对猪卵母细胞体外成熟的影响

A类卵母细胞在mTCM 199、NCSU2 3和NCSU37体系中培养 4 4～ 5 2小时后 ,成熟率分别为 76 .1%、78.1%和 6 5 .2 %。前两者差异不显著 (P >0 .0 5 ) ,但显著高于后者 (P <0 .0 5 )。卵母细胞在添加eCG和hCG的NCSU2 3体系中的成熟率 (75 .6 % )明显高于添加FSH的LH和成熟率 (6 5 .2 % ) (P <0 .0 5 )。A、B、C三类卵母细胞在NCSU2 3的成熟率分别为 73.3%、6 0 .4 %和 11.0 % ,三者间差异显著 (P <0 .0 5 )。大 (ф >6mm)、中 (ф =3～ 6mm)和小 (ф <3mm)三种卵泡中的卵母细胞在NCSU2 3中培养后 ,成熟率分别为 5 6 .2 % ,78.1%和 5 1.9% ,中等卵泡中卵母胞的体外成熟率显著高于其他两组 (P <0 .0 5 )。     

Effect of Follicle Size on In Vitro Maturation of Pre‐Pubertal Porcine Cumulus Oocyte Complexes

Very small follicles (<3.0 mm diameter) are over‐represented on the surface of ovaries of non‐cycling pigs, and the oocytes collected from these follicles generally have reduced developmental competence in vitro. This study examined the effect of follicle size on the nuclear maturation (n = 608), the potential of parthenogenetic activation (n = 243) and the cyclic AMP (cAMP) content of pre‐pubertal porcine oocytes (n = 480). In addition, the influence of follicle size on steroid hormone synthesis was analysed. Cumulus oocyte complexes (COCs) flushed from small (2.5–4.0 mm) or large (4.5–6.0 mm) ovarian follicles were cultured for 0, 28 and 46 h. After 46 h of IVM, a greater proportion of oocytes from 4.5‐ to 6.0‐mm follicles reach metaphase II (MII) compared with those from follicles with 2.5–4.0 mm of diameter (96.1 vs 77.0%, respectively; p < 0.001). Parthenogenetic activation of oocytes from large follicles produced higher developmental rates than oocytes from large follicles (p < 0.05). At 28 h, the IVM medium with oocytes from large follicles contained significantly more 17ß‐oestradiol (E₂) than the medium with oocytes from small follicles (5.55 vs 3.45 ng/ml, respectively; p < 0.05) and at 46 h, the medium with oocytes from small follicles contained significantly more progesterone (P₄) than the medium with oocytes from large follicles (276.7 vs 108.2 ng/ml, respectively, p < 0.05). Porcine oocytes from large follicles have higher nuclear and cytoplasmic maturation capacities, but the differences did not appear to be cAMP‐mediated. Our findings also suggest that COCs from small follicles undergo more intensive luteinization than COCs from large follicles. The results show that oocytes from follicles with a diameter greater than 4.0 mm are more suitable for in vitro studies.     

Cryopreservation of immature oocytes of the indigeneous Vietnamese Ban Pig

We report the cryopreservation of oocytes from Ban miniature pigs which are endemic in Vietnam. Immature cumulus‐oocyte complexes were collected from antral follicles of 7–8 mo old female cyclic Ban pigs and vitrified in micro‐drops. Oocyte morphology, lipid content, post‐warming survival, nuclear maturation, and embryo development were compared to those of oocytes from commercially slaughtered Landrace × Large white hybrid pigs. The size of oocytes in the two breeds was similar. However, significantly lower amounts of intracellular lipid were detected in Ban oocytes. There was no difference (p > 0.05) between Ban and Landrace × Large white oocytes in percentages of post‐warming survival (93.1 ± 3.4% vs. 70.7 ± 16.7%, respectively) and nuclear maturation after in vitro maturation (80.4 ± 5.1% vs. 90.0 ± 1.3% respectively). Similarly, cleavage (30.8 ± 7.8% vs. 10.3 ± 6.1%, respectively) and blastocyst development rates (9.4 ± 5.0% vs. 0.79 ± 0.79, respectively) were not different (p > 0.05) between vitrified Ban and Landrace × Large white oocytes after in vitro fertilization and embryo culture. In conclusion, high survival and maturation rates were achieved after vitrification of immature Ban oocytes and their cryo‐tolerance was similar to that of Landrace × Large white oocytes, despite the difference in lipid content. We succeeded to generate reasonable rates of blastocysts from vitrified Ban oocytes by in vitro fertilization.     

Effects of cumulus cells on rabbit oocyte in vitro maturation

Cumulus cells (CCs) are of great importance in oocyte development and maturation in many species, but detailed influence of CCs has not been extensively examined, especially on rabbit. The present study was designed to investigate the effects of CCs and the elongation of in vitro maturation (IVM) time on rabbit oocyte nuclear and ooplasmic maturation and survival. Cumulus oocyte complexes (COCs) and naked oocytes (NOs) were recovered directly from rabbits super-ovulated with eCG. Corona-enclosed oocytes (COs) and denuded oocytes (DOs) were obtained from COCs after removing a part or whole of CCs. The oocytes were cultured in the following seven groups. (i) Cumulus cell enclosed oocytes (CEOs) were cultured alone (CEOs); (ii) COs were cultured alone (COs); (iii) DOs were cultured alone (DOs); (iv) NOs were cultured alone; (v) DOs were co-cultured with COCs [DOs(COCs)]; (vi) DOs were co-cultured with CCs [DOs(CCs)]; (vii) NOs were co-cultured with CCs [NOs(CCs)]. After the oocytes were cultured for 24 and 30 h, the nuclear maturation was evaluated by first polar body (PB1) extrusion while the ooplasmic maturation was evaluated by the cleavage rate after parthenogenetic activation. The results showed that the nuclear maturation rate of CEOs, COs, DOs(COCs) and DOs(CCs) after 24 h incubation were significantly different from each other (p < or = 0.05), the rate of DOs(CCs) was similar to that of DOs (p > or = 0.05). The cleavage rates in the first two groups were significantly higher than those of the others (p < 0.05). For oocytes cultured for 30 h, the nuclear maturation rates were significantly different for each culture model (p < 0.05). The cleavage rates in first two groups were significantly higher than those of others (p < 0.05). Both the nuclear and cleavage rates significantly increased when the culture time of DOs(COCs) was prolonged from 24 to 30 h. DOs(CCs) nuclear maturation was significantly improved when the culture time was prolonged from 24 to 30 h, but the ooplasmic maturation was not. Few NOs incubated with or without CCs accomplished nuclear maturation (approximately 2% both), even when the culture time was prolonged from 24 to 30 h. The oocyte degeneration rates were significantly different for each culture model after both 24 and 30 h incubation (p < or = 0.05). There was no significant difference in oocyte degeneration in the same groups between 24 and 30 h incubation (p > 0.05). The results suggest that rabbit CCs affect oocyte nuclear and ooplasmic maturation, and their survival. The prolongation of the culture time of rabbit oocyte from 24 to 30 h improves the nuclear and ooplasmic maturation differently in the present system. Rabbit oocytes free of CCs, especially NOs, show weak meiotic resumption potential and compromised viability, which cannot be improved by co-culture with dispersed CCs. The degeneration mostly happens at early time of IVM.     

In vitro fertilisation of in vivo matured porcine oocytes obtained from prepuberal gilts at different time intervals after hCG injection

The goal of the present study was to find out the best interval after hCG injection in PMSG primed prepuberal gilts for retrieval of in vivo matured oocytes for in vitro fertilisation (IVF). Altogether 66 gilts were superovulated with 1500 IU PMSG and 500 IU hCG 72 h later. Ovum pick up was performed endoscopically 24, 28, 32 or 36 h after hCG and a total of 869 cumulus-oocyte-complexes (COCs) were aspirated from 1400 follicles. COCs were tested for quality, and an aliquot was immediately fixed and stained to determine meiotic configuration. The remaining COCs were fertilised in vitro using frozen-thawed epididymal semen. Quality and developmental stage of embryos were tested after IVF, and the number of nuclei was counted. At 24 to 32 h after hCG only few oocytes have entered the second meiotic cycle (18 to 25% vs. 58% at 36 h, p < 0.05). The overall cleavage rate was significantly influenced by insufficient maturation rate at the early collection times (14% at 24 h vs. 49% at 36 h). Additionally, when oocytes were collected 24 to 32 h vs. 36 h the cleavage rate based on mature oocytes was lower (26 vs. 62%, p < 0.05). Once embryonic development has been initiated, the further in vitro development to blastocyst stages did not differ between groups. However, the number of cells was lower at collection times 24 to 32 h as compared to 36 h after hCG (12 to 15 cells vs. 22 cells, p < 0.05). The results indicate that the time of COC collection affects the in vitro developmental competence up to the blastocyst stage and should not be performed earlier than 36 h after hCG treatment.     

马卵母细胞胞质内精子注射后体外发育能力的研究

本研究在非繁殖季节评估卵丘形态(松散型、致密型)、成熟培养体系(TCM 199、NCSU 23)、体外成熟时间(34、38 h)和离子霉素结合6-DMAP激活对马卵母细胞胞质内精子注射(ICSI)后体外发育能力的影响。从屠宰场采集马卵巢,获得的卵母细胞进行体外成熟,然后注射马冷冻解冻精液,统计分裂情况。试验结果表明,①马松散型卵母细胞成熟率显著高于致密型卵母细胞(P<0.05),分别为61.09%和41.24%,但ICSI后36 h分裂率无显著差异(P>0.05),分别为47.34%和44.92%;②两种培养体系对马松散型或致密型卵母细胞成熟率及ICSI后36 h分裂率无显著影响(P>0.05),但相同成熟体系培养松散型卵母细胞成熟率均显著高于致密型卵母细胞(P<0.05),然而ICSI后36 h分裂率差异不显著(P>0.05);③松散型或致密型卵母细胞在TCM 199或NCSU 23中成熟38 h成熟率均高于34 h成熟率,分别为44.43%～68.87%和34.52%～58.90%,松散型卵母细胞在TCM 199体系中成熟34 h、ICSI后激活组或对照组的分裂率显著高于成熟38 h、ICSI后激活组的分裂率(P<0.05),以及致密型卵母细胞在TCM 199体系中成熟34 h、ICSI后激活组的分裂率(P<0.05),而且显著高于松散型卵母细胞在NCSU 23体系中成熟38 h、ICSI后对照组的分裂率(P<0.05);④ICSI后用离子霉素结合6-DMAP激活对马卵母细胞ICSI后36 h分裂无显著影响(P>0.05)。因此,马松散型和致密型卵母细胞的成熟能力存在差异,TCM 199和NCSU 23成熟体系对这2种类型卵母细胞的发育能力无显著影响(P>0.05),马卵母细胞成熟38 h成熟率高于34 h成熟率,TCM 199成熟体系培养松散型卵母细胞34 h进行ICSI后的分裂率最高。离子霉素结合6-DMAP激活对TCM 199或NCSU 23体系成熟马卵母细胞ICSI后的体外发育能力无显著影响(P>0.05)。     

In Vitro Maturation of Dromedary (Camelus dromedarius) Oocytes: Effect of Different Protein Supplementations and Epidermal Growth Factor*

The present experiment was aimed to compare the effect of different protein supplementation sources, foetal calf serum (FCS), oestrous dromedary serum (EDS) and BSA, in experiment 1, and the effect of different concentrations of epidermal growth factor (EGF), in experiment 2, on in vitro nuclear maturation of the dromedary oocytes. Cumulus oocyte complexes (COCs) were harvested from the ovaries collected from a local slaughterhouse by aspirating the visible follicles in PBS supplemented with 5% FCS. Pooled COCs were randomly distributed to 4‐well culture plates containing 500 μl of the maturation medium and cultured at 38.5°C in an atmosphere of 5% CO₂ in air for 32–36 h. The basic maturation medium consisted of TCM‐199 supplemented with 0.1 mg/ml L‐glutamine, 0.8 mg/ml sodium bicarbonate, 0.25 mg/ml pyruvate, 50 μg/ml gentamicin, 10 μg/ml bFSH, 10 μg/ml bLH and 1 μg/ml estradiol. In experiment 1, this medium was supplemented with 10% FCS, 10% EDS or 0.4% BSA, whereas in experiment 2, it was supplemented with 0.4% BSA and 0, 10, 20 or 50 ng/ml of EGF. The oocytes were fixed, stained with 1% aceto‐orcein stain and their nuclear status was evaluated. Oocytes were classified as germinal vesicle, diakinesis, metaphase‐I, anaphase‐I (A‐I), metaphase‐II (M‐II) and those with degenerated, fragmented, scattered, activated or without visible chromatin as others. There was no difference (p > 0.05) observed in the proportion of oocytes reaching M‐II stage between the media supplemented with FCS (71.5 ± 4.8), EDS (72.8 ± 2.9) and BSA (72.7 ± 6.2). In experiment 2, a higher proportion (p < 0.05) of oocytes reached M‐II stage when the medium was supplemented with 20 ng/ml of EGF (81.4 ± 3.2) when compared with the media supplemented with 10 ng/ml (66.9 ± 4.1) and control (67.2 ± 7.1) groups. It may be concluded that the maturation media for dromedary camel oocytes can be supplemented with any of the three protein sources, i.e. FCS, EDS and BSA without any significant differences on the maturation rates. Also, a supplementation of 20 ng/ml of EGF in the maturation medium seems to be optimal and improves the nuclear maturation of dromedary camel oocytes.     

绵羊卵丘细胞对裸卵体外成熟及孤雌发育影响的研究

本研究探讨绵羊卵丘细胞对裸卵体外成熟和后期发育的影响。实验分为4组,对照组为卵丘-卵母细胞复合体(COCs);裸卵(DO)组;COCs与DO共培养组(CODO);卵丘细胞(CC)与DO共培养组(CCDO)。体外成熟培养18 h后,检测各组卵子成熟质量并进行孤雌发育研究。结果表明:CODO和CCDO组中裸卵活率显著高于DO组(P<0.05),但显著低于COCs组(P<0.05),且COCs组中卵子活率极显著高于DO组(P<0.01);在极体排出率方面,CODO、CCDO和DO3组差异不显著(P>0.05),但是它们都显著低于COCs组(P<0.05)。COCs、CODO、CCDO和DO 4组卵裂率差异均不显著(P>0.05)。然而,DO组的囊胚率显著低于CODO和CCDO组(P<0.05),极显著低于COCs组(P<0.01),但CODO和CCDO 2组中裸卵的囊胚率差异不显著(P>0.05)。总之,无论散在的卵丘细胞还是COCs均能提高裸卵体外成熟及后期发育潜力。