猪体细胞核移植重构胚的体外发育

以卵丘细胞为核供体细胞组成重构胚,卵裂率达到56．7％,发育至桑椹胚率达到11．7％,囊胚率为6．7％,显著高于成纤维细胞重构胚（P＜0．05）。本文还研究了卵母细胞的采集方法、激活程序和卵龄对卵丘细胞核移植重构胚体外发育的影响。以血清饥饿法将卵丘细胞诱导G0/G1期,抽吸法／解剖法采集卵母细胞,体外培养33－44h,将卵丘细胞放至去核卵母细胞的卵周隙中,重构胚以钙离子载体A23817或电脉冲结合6－DMAP激活处理,体外培养6d。研究表明,卵母细胞采集方法、激活液中细胞松驰素（CB）、激活程度并不影响重构胚的发育（以卵龄44h的卵母细胞为受体）;而以电脉冲结合6－DMAP激活处理能提高重构胚发育能力（以卵龄33h的卵母细胞为受体）（P＜0．05）。本研究显示,以电脉冲结合6－DMAP激活卵丘细胞重构胚,体外能发育至囊胚。     

猪体细胞核移植重构胚的体外发育(英文)

以卵丘细胞为核供体细胞组成重构胚 ,卵裂率达到 5 6.7% ,发育至桑椹胚率达到1 1 .7% ,囊胚率为 6.7% ,显著高于成纤维细胞重构胚 (P <0 .0 5 )。本文还研究了卵母细胞的采集方法、激活程序和卵龄对卵丘细胞核移植重构胚体外发育的影响。以血清饥饿法将卵丘细胞诱导至G0 G1 期 ,抽吸法 解剖法采集卵母细胞 ,体外培养 3 3～ 44h ,将卵丘细胞放至去核卵母细胞的卵周隙中 ,重构胚以钙离子载体A2 3 81 7或电脉冲结合 6 DMAP激活处理 ,体外培养 6d。研究表明 ,卵母细胞采集方法、激活液中细胞松弛素 (CB)、激活程序并不影响重构胚的发育 (以卵龄 44h的卵母细胞为受体 ) ;而以电脉冲结合 6 DMAP激活处理能提高重构胚发育能力 (以卵龄 3 3h的卵母细胞为受体 ) (P <0 .0 5 )。本研究显示 ,以电脉冲结合 6 DMAP激活卵丘细胞重构胚 ,体外能发育至囊胚     

影响猪体细胞核移植重构胚体外发育的若干因素

以卵丘细胞为核供体细胞组成重构胚,卵裂率达到56.7%,发育至桑椹胚达11.7%、孵化囊胚率为6.7%,显著高于成纤维细胞组成的重构胚(p<0.05)。我们研究了卵母细胞的采集方法,激活方法和卵龄对卵丘细胞核移植重构胚体外发育的影响。以血清饥饿法将卵丘细胞诱导至GO或G1期,抽吸法/解剖法采集卵母细胞,体外培养33或44 h,将卵丘细胞置于去核卵母细胞的卵周隙中,重构胚以钙离子载体A23817或电脉冲结合6-DMAP激活处理,体外培养6天,结果表明,卵母细胞采集方法、激活液中细胞松弛素(CB)并不影响重构胚的发育(以卵龄44h的卵母细胞为受体);而以电脉冲结合6-DMAP激活处理能提高重构胚发育能力(以卵龄33 h的卵母细胞为受体)(p<0.05)。本研究显示,以电脉冲结合6-DMAP激活卵丘细胞重构胚,能在体外发育至囊胚     

化学联合激活可明显提高小鼠孤雌胚胎发育率

为探讨一种高效的小鼠卵母细胞孤雌激活的方案,进一步提高孤雌囊胚发育率。用不同浓度的氯化锶及不同作用时间的乙醇,并分别联合6-DMAP对不同卵龄小鼠卵母细胞进行活化,统计小鼠卵母细胞卵裂率和体外发育状况。结果显示,15～16h、18～19h和20～21h卵龄组卵母细胞经6mmol/LSrCl2联合6-DMAP处理后,三组的激活率随卵龄增长而升高,其中20～21h卵龄组显著高于15～16h、18～19h组(P<0.05),激活胚胎的发育率以18～19h时最高;6mmol/L和10mmol/L的SrCl2联合6-DMAP均能有效地激活小鼠卵母细胞,激活率分别为76.4%和83.6%,桑葚胚率分别为50.0%和56.3%;70ml/L乙醇联合6-DMAP以处理7min组获得了较好的激活率和囊胚发育率,分别为77.1%和42.4%,囊胚率均显著高于4min和10min处理组(P<0.05)。6-DMAP与SrCl2或乙醇联合应用可以有效抑制第二极体的排出,提高激活胚的二倍体比率;孤雌囊胚的平均细胞数显著低于正常受精囊胚(P<0.05)。不同激活方案对孤雌活化胚的核型和发育能力的作用差异较大,小鼠卵母细胞孤雌激活率与卵龄...     

不同卵龄小鼠卵母细胞激活和受精的比较研究

本实验比较了不同卵龄的小鼠卵母细胞受酒精人工刺激后的激活率和体外受精率,以探索卵母细胞激活和受精的机制。向NIH雌鼠腹腔注射孕马血清促性腺激素（PMSG）7．5单位,48小时后注射人绒毛膜促性激素（HCG）7．5单位,于不同时间杀小鼠,取卵母细胞与卵丘细胞的复合体（OCC）。从注射HCG后到取OCC的时间视为卵母细胞的卵龄。将OCC置于含8％酒精的M2中7分钟,再在16中培养5小时后,用0．3mg/mL的透明质酸酶去卵丘细胞。卵母细胞形成原核或速即卵裂为激活的标志,将OCC加入已获能的精子悬液中,5小时后将从卵丘细胞中释放出来的卵母细胞转移到M16中,将日发生卵裂为卵母细胞体外受精和激活的标志。小鼠卵母细胞卵龄为20h,其激活率为81．6％,速即卵裂率为48．0％;而卵龄进一步增加到24h,激活率和卵裂率转为下降（Table1）。而卵母细胞受精子激活和受精则不同,卵龄为15h ,卵母细胞的体外受精率为45．4％;随着卵龄的进一步增加,体外受精率则下降（Table2)。Fig.1显示：新排出的卵母细胞容易被精子激活而受精;卵龄较大的卵母细胞较易被酒精的人工刺激而激活。可能是卵母细胞从成熟到老化过程中,细胞的结构、功能及对外界刺激的敏感状态都在发生一些规律性的变化,而激活和受精的机制不完全,还不能精对卵龄的要求要严格。     

改进的培养体系在小鼠体细胞核移植及重构胚ES细胞分离培养中的应用

取8周后的雌性昆明小鼠进行超排,取卵母细胞用作核受体,收集卵母细胞周围的卵丘细胞作核供体,进行体细胞核移植。核移植重构胚经SrCl2激活处理6h后,与改良的M16培养液和小鼠输卵管上皮细胞共培养;将发育到早期囊胚阶段的重构胚转移至小鼠胎儿成纤维细胞饲养层上,添加含心肌细胞培养液的ES细胞培养液;把孵出的ICM进行消化接种培养,对孵出的ES细胞集落进行鉴定培养。结果显示,以小鼠卵丘细胞为核供体,体细胞核移植重构胚激活率为65．23％,囊胚发育率为11．69％;9个核移植重构囊胚中分离出ES细胞集落,分离率为2．77％;分离出的核移植ES细胞集落具有岛屿状团状隆起结构、碱性磷酸酶染色呈阳性,体外分化可形成类胚体,并能分化成上皮样或梭形细胞。ES细胞集落经常规冻存和复苏后,显示出同冻存前相似的集落形态,并具有较强的增殖能力。实验证实小鼠输卵管上皮细胞、改良的M16培养液及含心肌细胞培养液的ES细胞培养液可以更为成功地运用于小鼠的体细胞核移植及ES细胞的分离培养研究。     

体细胞的组织来源及培养代数对猪核移植重构胚发育的影响

本研究系统探讨了体细胞的组织来源及培养代数对猪核移植重构胚发育的影响。体外成熟培养40-44h的猪卵母细胞去核后,将经血清饥饿(0．5?s)培养2-9d、0．1mg/L Aphidicolin (APD)培养 0．5?S培养2-9d或一般培养法(10?S)培养的卵丘细胞、颗粒细胞、输卵管上皮细胞和耳皮成纤维细胞,直接注射到去核的卵母细胞质中,或注射到卵周隙中。再经电融合(100V/mm,30μs,电脉冲1次)构建重构胚。重构胚以钙离子载体A23817或电脉冲结合6- DMAP激活处理,体外培养6天。耳皮成纤维细胞和颗粒细胞经0．1mg/L APD 0．5?S培养处理后的重组胚卵裂率,均高于血清饥饿和一般培养处理的同种供体细胞(P＜0．01)。卵丘细胞、颗粒细胞经0．1mg/L APD 0．5?S处理后进行核移植的分裂率和发育率均高于输卵管上皮细胞和耳皮成纤维细胞(P＜0．05)。以猪颗粒细胞为核供体时,电融合法的重构胚分裂率显著高于胞质内注入法(P＜0．05),但囊胚发育率无显著差异(P＞0．05)。培养3代和6代的猪颗粒细胞以及培养6代和10代的耳皮成纤维细胞,其具有正常二倍染色体的细胞比例均无显著差异(P＞0．05);以这2种细胞不同培养代数做供体进行核移植时,各代之间核移胚的体外分裂率、囊胚发育率无显著差异(P＞0．05)。这些结果表明：(1)猪耳皮成纤维细胞和颗粒细胞经培养传代所建立起来的细胞系相对比较稳定;(2)0．1mg/L APD预培养处理供体细胞能提高猪体细胞核移植的效果,血清饥饿培养则无明显效果;(3)猪颗粒细胞和耳皮成纤维细胞等均可做供核细胞．核移植后都能得到体细胞克隆的囊胚,但前者的效果略优于后者,且其核移植效果不受供核细胞培养代数的影响;(4)电融合核移植胚胎的发育率高于胞质内直接注入法,但两者的总体效率相近。     

影响山羊体外受精的因素

以屠宰山羊卵母细胞为材料研究了公羊个体、附睾不同部位精子、成熟培养和受精时卵丘存在与否、卵丘扩展程度及卵龄对山羊体外受精的影响。结果表明 :1)不同公羊精液在受精、卵裂和桑椹 /囊胚率上都有显著差异 ;2 )附睾尾精子和鲜精的受精、卵裂和桑椹 /囊胚率无显著差异 ,但显著高于附睾体和附睾头精子 ;3)成熟培养 2 4和 2 7h卵母细胞的的桑椹胚 /囊胚率显著高于培养 2 1和 30h卵母细胞 ;4 )卵丘扩展 3和 4级卵母细胞受精和桑椹胚 /囊胚率显著高于扩展 0和 1级卵母细胞 ;5 )成熟培养前机械去卵丘严重影响卵母细胞体外受精和桑椹胚 /囊胚率 ;6 )受精前完全去掉卵丘显著影响桑椹胚 /囊胚率     

山羊品种间体细胞核移植研究

萨能奶山羊是著名的奶用山羊品种,波尔山羊则是世界著名的肉用山羊品种。为了研究波尔山羊体细胞在奶山羊卵母细胞中的去分化,我们针成年波尔山羊的颗粒细胞或耳皮肤成纤维细胞作为供核细胞（试验组）,移入奶山羊中Ⅱ期的去核卵母细胞透明带下,经电融合和离子霉素与6－二甲基氨基嘌呤－DMAP）激活,直接移入同期发情奶山羊输卵管或经体内培养,将发育的重构胚移入同期发情羊子宫内。妊娠早期作B超诊断,确立妊娠的观察至足月。同时将奶山羊的35日龄胎儿成纤维细胞作供核细胞（对照组）,按试验组同样方法处理,将重构胚直接移入同期发情的奶山羊输卵管内。结果：试验组,波尔羊颗粒粒细胞与耳皮肤成纤维2细胞的融合率分别为78．2％（115／147）,57．4％（116／202）,重构胚卵裂率为85．8％（115／134）,桑椹胚,囊胚的发育率38．8％（52／134）,早期妊娠三头,分别于妊娠40,60,60日龄终止妊娠。对照组,融合率为89．5％（136／152）,早期妊娠率为42．9％（6／14）,四头受体足月分娩,产四头公羊羔,其中三头存活,一头分娩时死于肺不扩张,并体重过大,显示胎儿过大综合症。经基因型鉴定证实,这四头克隆羔羊均源于同一胎儿成纤维细胞系。以上结果表明,波尔羊体细胞核在奶山羊卵母细胞中能够去分化,并维持一定程度的发育。     

家兔胚胎细胞核移植的研究

本研究以兔为实验材料,对细胞核过程中显微操作、电融合、电活化以及移核胚的培养等基本问题进行了研究。对兔进行PMSG－hCG超数排卵,收集成熟母细胞和16－细胞胚;后者经胰蛋白酶消化,去除胶膜和透明带,在不含Ca62 、Mg^2 的分离中分成单个卵裂球;然后,分别对两者做CB预处理;首次尝试采用WQilladsen法,去除卵母细胞核、并将单个卵裂球注入透明带,同时、与McGrath-Solter法进行比较;通过电融合使供体核进入去核的卵母细胞内;将所得移核胚在体外或在中间内体内培养并观察。结果表明：一、Willadsen法与McGrath-Solter法比较,核移植操作的成功率及以后的电融合率均无明显差异（Tab.1)。相对于后者,Willadsen法更简便、易于掌握并提高去核率。二、hCG超排注射后13－15h,观察卵母细胞发现：其中,67．8％保留有第一极体。此时的卵子若去除1／3胞质量,去核率可以达到58．3％。若推迟去核时间,第一极体退化,失去去核标志。三、比较不同电脉冲条件,发现强度为0．63kv/cm,持续160μs的一次电脉冲可获较高移核胚的融合率（70．8％）（Tab.2）;并可使61．1％的成熟卵母细胞活化。四、比较移核胚在体外和在中间有体内两种培养条件,前者只有34．6％能发育到6－8细胞期,而后者有23．0％能发育到桑椹胚或囊胚（Tab.3)。说明：需进一步优化家兔胚体外培养条件。     

不同供体细胞及其处理对猪核移植重构胚体外发育的影响

系统探讨了体细胞的组织来源及培养代数对猪核移植重构胚发育的影响。体外成熟培养40~44 h的猪卵母细胞去核后, 将经血清饥饿(0.5%FBS)培养2~9天、0.1 mg/L Aphidicolin(APD)培养+0.5% FBS培养2~9天或一般培养法(10% FBS)培养的卵丘细胞、颗粒细胞、输卵管上皮细胞和耳皮成纤维细胞, 直接注射到去核的卵母细胞质中, 或注射到卵周隙中, 再经电融合(100 V/mm, 30 [mu]s, 电脉冲1次)构建重构胚。重构胚以钙离子载体A23817 或电脉冲结合6-DMAP 激活处理, 体外培养6天。耳皮成纤维细胞和颗粒细胞经0.1 mg/L APD + 0.5% FBS培养处理后的重组胚卵裂率, 均高于血清饥饿和一般培养处理的同种供体细胞(P<0.01)。卵丘细胞、颗粒细胞经0.1 mg/L APD + 0.5% FBS处理后进行核移植的分裂率和发育率均高于输卵管上皮细胞和耳皮成纤维细胞(P<0.05)。以猪颗粒细胞为核供体时, 电融合法的重构胚分裂率显著高于胞质内注入法(P<0.05), 但囊胚发育率无显著差异(P>0.05)。培养3代和6代的猪颗粒细胞以及培养6代和10代的耳皮成纤维细胞, 其具有正常二倍染色体的细胞比例均无显著差异(P>0.05); 以这2种细胞不同培养代数做供体进行核移植时, 各代之间核移胚的体外分裂率、囊胚发育率无显著差异(P>0.05)。这些结果表明: (1) 猪耳皮成纤维细胞和颗粒细胞经培养传代所建立起来的细胞系相对比较稳定; (2) 0.1 mg/L APD预培养处理供体细胞能提高猪体细胞核移植的效果, 血清饥饿培养则无明显效果; (3) 猪颗粒细胞和耳皮成纤维细胞等均可做供核细胞, 核移植后都能得到体细胞克隆的囊胚, 但前者的效果略优于后者, 且其核移植效果不受供核细胞培养代数的影响; (4) 电融合核移植胚胎的发育率高于胞质内直接注入法, 但两者的总体效率相近。     

Effects of maturational age of recipient oocytes and activation conditions on the development of porcine fetal fibroblast nuclear transfer embryos

This study was conducted to evaluate the nuclear remodeling patterns and the developmental potential of porcine fetal fibroblast nuclear transfer embryos (NTs) following the maturational age of recipient oocytes and activation conditions. Donor cells were transferred into the enucleated oocytes that were matured for 36 or 44h. Electrofused embryos were cultured in PZM-3 for 6 days without activation treatment (EF group). Some of these embryos were additionally activated by electric stimulus (ES; EF+ES group) or a combination of ES and DMAP (EF+ES+D group) before culture. The reconstituted embryos were fixed 2.5h after fusion to evaluate the nuclear remodeling patterns. The nuclear remodeling pattern of NTs reconstituted with 44 h-matured recipients showed a tendency to form a pronucleus-like structure, while that of NTs reconstituted with 36 h-matured recipients showed a tendency to undergo a premature chromosome condensation (PCC) and form one set of chromatin clump. In EF+ES+D group, blastocyst development was significantly increased regardless of maturational age of recipient oocytes (P<0.05). The result indicates that additional activation treatment is necessary to induce the activation of embryos reconstituted with 36 h-matured recipients, and treatment with the combination of electrical stimuli and DMAP could enhance the blastocyst formation rate of porcine NTs reconstituted with both 36 h- and 44 h-matured recipient oocytes.     

Development and calcium level changes in pre-implantation porcine nuclear transfer embryos activated with 6-DMAP after fusion

This study investigated the effect of treatment with 6-dimethylaminopurine (6-DMAP) following fusion on in vitro development of porcine nuclear transfer (NT) embryos. Frozen thawed ear skin cells were transferred into the perivitelline space of enucleated oocytes. Reconstructed oocytes were fused and activated with electric pulse in 0.3 M mannitol supplemented with either 0.1 or 1.0 mM CaCl(2). In each calcium concentration, activated oocytes were divided into three groups. Two groups of them were exposed to either ionomycin (I + 6-DMAP or 6-DMAP alone. In experiment 2, fused NT embryos in 0.3 M mannitol containing 1.0 mM CaCl(2) were exposed to 6-DMAP either immediately or 20 min after fusion/activation. For 0.1 mM CaCl(2), oocytes activated with either I + 6-DMAP or 6-DMAP alone showed a higher (P < 0.05) developmental rate to the blastocyst stage than those activated with an electric pulse alone (26.7 and 22.5 vs. 12.5%). For 1.0 mM CaCl(2), oocytes activated with either I + 6-DMAP or 6-DMAP alone showed significantly higher (P < 0.05) developmental rate to the blastocyst stage (35.6 and 28.3 vs. 19.8%). Developmental rate to the blastocyst stage was (P < 0.05) increased in NT embryos activated with 6-DMAP 20 min after fusion. 6-DMAP made a higher and wider Ca(2+) transient compared to that induced by electric pulses (Fig. 3). The fluctuation lasted during the time that oocytes were cultured in 6-DMAP. Regardless of Ca(2+) concentration in fusion medium, activation with 6-DMAP following electric pulses supported more development of porcine NT embryos. Activation of NT embryos with 6-DMAP after fusion in the presence of 1.0 mM CaCl(2) could support better developmental rate to the blastocyst stage.     

Cloned piglets born after nuclear transplantation of embryonic blastomeres into porcine oocytes matured in vivo

Nuclear transplantation in the pig is more difficult than in other domestic animals and only one embryonic nuclear transplantation (NT) pig has been born to date. In this study, reconstituted porcine embryos were produced by electrofusion of blastomeres from in vivo four-cell embryos to enucleated in vivo or in vitro matured (IVM) oocytes. Nuclear transfer using cumulus cells as nuclear donors was also conducted. When blastomeres were used as donors, the electrofusion rate was significantly higher in oocytes matured in vivo (91.5%) than in those matured in vitro (66.1%) (p < 0.01). After fusion, the NT embryos reconstituted from in vivo matured oocytes developed to blastocysts at a rate of 10.3% after culture in rabbit oviducts for up to 5 days, while only 5.9% of the NT embryos reconstructed from in vitro matured oocytes developed to blastocyst stage. Electrofusion rate of cumulus cell nuclei with enucleated IVM oocytes was lower (47.6%) and only 1.5% (2/136) of the reconstituted eggs developed in vitro to morula stage, and 1.9% developed to blastocysts when cultured in the ligated rabbit oviducts. Transfer of 94 embryos reconstructed by blastomere NT with in vivo matured oocytes to five synchronous recipients resulted in the birth of two cloned piglets. No piglet was born following transfer to two recipients of embryos (n = 39) derived from NT with in vitro matured oocytes. The results demonstrate that in vivo matured oocytes are better recipients than those matured in vitro for pig cloning.     

Effects of duration, concentration, and timing of ionomycin and 6-dimethylaminopurine (6-DMAP) treatment on activation of goat oocytes

The protocol of ionomycin followed by 6-dimethylaminopurine (6-DMAP) is commonly used for activation of oocytes and reconstituted embryos. Since numerous abnormalities and impaired development were observed when oocytes were activated with 6-DMAP, this protocol needs optimization. Effects of concentration and treatment duration of both drugs on activation and development of goat oocytes were examined in this study. The best oocyte activation (87-95%), assessed by pronuclear formation, was obtained when oocytes matured in vitro for 27 hr were treated with 0.625-20 microM ionomycin for 1 min before 6-hr incubation in 2 mM 6-DMAP. Progressional reduction of time for 6-DMAP-exposure showed that the duration of 6-DMAP treatment can be reduced to 1 hr from the second up to the fourth hour after ionomycin, to produce activation rates greater than 85%. Activation rates of oocytes in vitro matured for 27, 30, and 33 hr were higher (P < 0.05) than that of oocytes matured for 24 hr when treated with ionomycin plus 1-hr (the third hour) 6-DMAP, but a 4-hr incubation in 6-DMAP enhanced activation of the 24-hr oocytes. Goat activated oocytes began pronuclear formation at 3 hr and completed it by 5-hr post ionomycin. An extended incubation in 6-DMAP (a) impaired the development of goat parthenotes, (b) quickened both the release from metaphase arrest and the pronuclear formation, and (c) inhibited the chromosome movement at anaphase II (A-II) and telophase II (T-II), leading to the formation of one pronucleus without extrusion of PB2. In conclusion, duration, concentration, and timing of ionomycin and 6-DMAP treatment had marked effects on goat oocyte activation, and to obtain better activation and development, goat oocytes matured in vitro for 27 hr should be activated by 1 min exposure to 2.5 microM ionomycin followed by 2 mM 6-DMAP treatment for the third hour.     

Development of rabbit parthenogenetic oocytes and nuclear-transferred oocytes receiving cultured cumulus cells

The present study determined a suitable parthenogenetic activation procedure for rabbit oocytes and examined the developmental potential of enucleated oocytes receiving cultured cumulus cells. Unfertilized oocytes recovered from superovulated rabbits were activated with one or two sets of electrical pulses, with or without subsequent administration of 6-dimethylaminopurine (6-DMAP). The proportion of oocytes treated with one or two sets of electrical pulses and 6-DMAP that cleaved (87% and 98%, respectively) and developed into blastocysts (77% and 85%, respectively) was significantly higher (P < 0.05) than those activated with electrical pulses alone (30% and 42% for cleavage, 7% and 17% for blastocysts). Cumulus cells separated from ovulated oocytes obtained from mature rabbits were cultured for three to five passages and then induced to quiescence by serum starvation before nuclear transfer. The enucleated oocytes receiving cumulus cells were activated with electrical pulses followed by the addition of 6-DMAP, and cultured in vitro for 5 to 6 d or transferred to pseudopregnant recipient females 1 d after activation. Of 186 nuclear-transferred oocytes, 123 (66%) cleaved and 42 (23%) developed into blastocysts. After transfer of 174 nuclear-transferred oocytes to 8 recipient females, a total of 3 implantation sites were observed in 3 recipient females but no fetuses were obtained.     

Oocyte activation procedures and influence of serum on porcine oocyte maturation and subsequent parthenogenetic and nuclear transfer embryo development

The viability of SCNT embryos is poor, with an extremely low cloned piglet production rate. In the present work, we studied the effect of three activation protocols based on ionomycin treatment (5 microM ionomycin for 5 min and incubated in 2 mM 6-DMAP for 3.5 h) or electric stimuli (two square wave electrical DC pulses of 1.2 kV/cm for 30 micros) combined or not with 6-DMAP on parthenogenetic embryo development. Oocytes activated by ionomycin plus 6-DMAP showed lower cleavage (47.2 vs. 78.5-81.5; p < 0.05) and blastocyst rates (11.3 vs. 29.2-32.1; p < 0.05) than those activated by electrical and electrical plus 6-DMAP treatments. Also, we studied the effect of addition of serum to maturation medium (0% vs. 10%) on nuclear maturation and further parthenogenetic and SCNT embryo development. We observed in the parthenogenetic embryos that cleavage rates in the serum-free group were significantly higher than in the serum-supplemented group (81.8 vs. 69.6% respectively; p < 0.05), although these differences were not detected in blastocyst rates or blastocyst nuclei numbers. Regarding SCNT embryos, no significant differences were observed in cleavage or blastocyst rates between different experimental groups of SCNT embryos. In conclusion, electrical pulse followed or not by 6-DMAP was found to be an efficient procedure to artificially activate MII porcine oocytes. Moreover, the addition of serum to oocyte maturation media did not seem to improve parthenogenetic or SCNT porcine embryo development.