start-ver=1.4 cd-journal=joma no-vol=13 cd-vols= no-issue= article-no= start-page=RP99936 end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2025 dt-pub=20250811 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Redistribution of fragmented mitochondria ensures symmetric organelle partitioning and faithful chromosome segregation in mitotic mouse zygotes en-subtitle= kn-subtitle= en-abstract= kn-abstract=In cleavage-stage embryos, preexisting organelles partition evenly into daughter blastomeres without signi?cant cell growth after symmetric cell division. The presence of mitochondrial DNA within mitochondria and its restricted replication during preimplantation development makes their inheritance particularly important. While chromosomes are precisely segregated by the mitotic spindle, the mechanisms controlling mitochondrial partitioning remain poorly understood. In this study, we investigate the mechanism by which Dynamin-related protein 1 (Drp1) controls the mitochondrial redistribution and partitioning during embryonic cleavage. Depletion of Drp1 in mouse zygotes causes marked mitochondrial aggregation, and the majority of embryos arrest at the 2 cell stage. Clumped mitochondria are located in the center of mitotic Drp1-depleted zygotes with less uniform distribution, thereby preventing their symmetric partitioning. Asymmetric mitochondrial inheritance is accompanied by functionally inequivalent blastomeres with biased ATP and endoplasmic reticulum Ca2+ levels. We also find that marked mitochondrial centration in Drp1-depleted zygotes prevents the assembly of parental chromosomes, resulting in chromosome segregation defects and binucleation. Thus, mitochondrial fragmentation mediated by Drp1 ensures proper organelle positioning and partitioning into functional daughters during the first embryonic cleavage. en-copyright= kn-copyright= en-aut-name=GekkoHaruna en-aut-sei=Gekko en-aut-mei=Haruna kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=NomuraRuri en-aut-sei=Nomura en-aut-mei=Ruri kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=KuzuharaDaiki en-aut-sei=Kuzuhara en-aut-mei=Daiki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=KaneyasuMasato en-aut-sei=Kaneyasu en-aut-mei=Masato kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=KosekiGenpei en-aut-sei=Koseki en-aut-mei=Genpei kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= en-aut-name=AdhikariDeepak en-aut-sei=Adhikari en-aut-mei=Deepak kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=6 ORCID= en-aut-name=MioYasuyuki en-aut-sei=Mio en-aut-mei=Yasuyuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=7 ORCID= en-aut-name=CarrollJohn en-aut-sei=Carroll en-aut-mei=John kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=8 ORCID= en-aut-name=KonoTomohiro en-aut-sei=Kono en-aut-mei=Tomohiro kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=9 ORCID= en-aut-name=FunahashiHiroaki en-aut-sei=Funahashi en-aut-mei=Hiroaki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=10 ORCID= en-aut-name=WakaiTakuya en-aut-sei=Wakai en-aut-mei=Takuya kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=11 ORCID= affil-num=1 en-affil=Department of Animal Science, Graduate School of Environment and Life Science, Okayama University kn-affil= affil-num=2 en-affil=Department of Animal Science, Graduate School of Environment and Life Science, Okayama University kn-affil= affil-num=3 en-affil=Reproductive Centre, Mio Fertility Clinic kn-affil= affil-num=4 en-affil=Department of Animal Science, Graduate School of Environment and Life Science, Okayama University kn-affil= affil-num=5 en-affil=Department of Animal Science, Graduate School of Environment and Life Science, Okayama University kn-affil= affil-num=6 en-affil=Development and Stem Cell Program and Department of Anatomy and Developmental Biology, Monash Biomedicine Discovery Institute, Monash University kn-affil= affil-num=7 en-affil=Reproductive Centre, Mio Fertility Clinic kn-affil= affil-num=8 en-affil=Development and Stem Cell Program and Department of Anatomy and Developmental Biology, Monash Biomedicine Discovery Institute, Monash University kn-affil= affil-num=9 en-affil=Department of Bioscience, Tokyo University of Agriculture kn-affil= affil-num=10 en-affil=Department of Animal Science, Graduate School of Environment and Life Science, Okayama University kn-affil= affil-num=11 en-affil=Department of Animal Science, Graduate School of Environment and Life Science, Okayama University kn-affil= END start-ver=1.4 cd-journal=joma no-vol=236 cd-vols= no-issue= article-no= start-page=74 end-page=81 dt-received= dt-revised= dt-accepted= dt-pub-year=2025 dt-pub=20250401 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Characteristics of porcine oocyte-cumulus complexes derived from various sizes of antral follicles and classified by brilliant cresyl blue staining, and developmental competence of the oocytes en-subtitle= kn-subtitle= en-abstract= kn-abstract=The present study sought to determine the characteristics of porcine oocyte-cumulus complexes (OCCs) derived from very small and small antral follicles (with less than 1 mm and 1?3 mm in diameter, respectively; VSF and SF) in comparison with controls from medium ones (with 3?6 mm in diameter; MF). Additionally, the present study examined the utility of brilliant cresyl blue (BCB) staining for assessing these OCCs. The incidence of BCB- oocytes in VSF- and SF-derived OCCs was higher than that in MF-derived OCCs. Although the meiotic and developmental competences of BCB+ oocytes from MF were superior to those from VSF and SF, blastocysts were successfully obtained from BCB+ oocytes even derived from VSF. The mean numbers of both total and viable cumulus cells surrounding an oocyte were significantly affected not only by the origin of the OCCs, but also by the BCB status of the oocytes (largest in MF-derived OCCs containing BCB+ oocytes). Although the outer and inner diameters of zona pellucida were affected by the origin of OCCs and the BCB status of oocytes (largest in MF-derived oocytes), the ooplasmic diameter of BCB+ oocytes did not differ among those derived from VSF, SF, and MF. Regardless of the BCB status, the transcriptional levels of G6PD and TKT in cumulus cells decreased during follicular development from VSF to MF, whereas the RPIA mRNA level in cumulus cells of MF-derived BCB+ OCCs was lower than in the others. These results underscore the utility of BCB staining for selecting MF-, SF-, and even VSF-derived OCCs containing oocytes with relatively higher meiotic and developmental competences, as well as the importance of having a sufficient number of healthy cumulus cells expressing genes related to the pentose phosphate pathway at lower levels. en-copyright= kn-copyright= en-aut-name=VanPhong Ngoc en-aut-sei=Van en-aut-mei=Phong Ngoc kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=DoSon Quang en-aut-sei=Do en-aut-mei=Son Quang kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=FonsekaWanniarachchige Tharindu Lakshitha en-aut-sei=Fonseka en-aut-mei=Wanniarachchige Tharindu Lakshitha kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=WakaiTakuya en-aut-sei=Wakai en-aut-mei=Takuya kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=FunahashiHiroaki en-aut-sei=Funahashi en-aut-mei=Hiroaki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= affil-num=1 en-affil=Department of Animal Science, Graduate School of Environmental and Life Science, Okayama University kn-affil= affil-num=2 en-affil=Department of Animal Science, Graduate School of Environmental and Life Science, Okayama University kn-affil= affil-num=3 en-affil=Department of Animal Science, Graduate School of Environmental and Life Science, Okayama University kn-affil= affil-num=4 en-affil=Department of Animal Science, Graduate School of Environmental and Life Science, Okayama University kn-affil= affil-num=5 en-affil=Department of Animal Science, Graduate School of Environmental and Life Science, Okayama University kn-affil= END start-ver=1.4 cd-journal=joma no-vol=234 cd-vols= no-issue= article-no= start-page=125 end-page=132 dt-received= dt-revised= dt-accepted= dt-pub-year=2025 dt-pub=20250301 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Mitochondrial content and mtDNA copy number in spermatozoa and penetrability into oocytes en-subtitle= kn-subtitle= en-abstract= kn-abstract=The current narrative review aims to summarize the relation of mitochondrial content (MC) and mitochondrial DNA copy number (MDCN) in spermatozoa with sperm penetrability, and to discuss the various determining factors during the process of spermatogenesis in mammals. There are many potential factors associated with the quantitative alteration of MC and MDCN in male gametes from spermatogenesis to ejaculation. Particularly, spermatogenesis may be the first step to jointly contribute to an incomplete reduction of MC and MDCN in spermatozoon. It appears to be now quite clear that some abnormalities during spermatogenesis and oxidative stress are the main factors highly associated with the quantitative change of MC and MDCN in spermatozoa, consequently affecting sperm quality and their penetrability into oocytes. Currently, a series of proteins contributing to form sperm midpiece during spermatogenesis and cytoplasmic elimination during spermiation have been currently identified. The present review provides insight into how these factors interact with sperm MC and MDCN, and handholds to gain a better understanding of their roles. This review also highlights the uniqueness of normal fertile spermatozoa which have relatively lower MC and MDCN, but have mitochondria that function completely in multiple pivotal physiological pathways. en-copyright= kn-copyright= en-aut-name=NguyenHai Thanh en-aut-sei=Nguyen en-aut-mei=Hai Thanh kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=DoSon Quang en-aut-sei=Do en-aut-mei=Son Quang kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=WakaiTakuya en-aut-sei=Wakai en-aut-mei=Takuya kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=FunahashiHiroaki en-aut-sei=Funahashi en-aut-mei=Hiroaki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= affil-num=1 en-affil=Department of Animal Science, Okayama University kn-affil= affil-num=2 en-affil=Department of Animal Science, Okayama University kn-affil= affil-num=3 en-affil=Department of Animal Science, Okayama University kn-affil= affil-num=4 en-affil=Department of Animal Science, Okayama University kn-affil= en-keyword=Spermatozoa kn-keyword=Spermatozoa en-keyword=Mitochondria kn-keyword=Mitochondria en-keyword=Mitochondrial DNA kn-keyword=Mitochondrial DNA en-keyword=Penetrability kn-keyword=Penetrability en-keyword=Spermatogenesis kn-keyword=Spermatogenesis END start-ver=1.4 cd-journal=joma no-vol=228 cd-vols= no-issue= article-no= start-page=30 end-page=36 dt-received= dt-revised= dt-accepted= dt-pub-year=2024 dt-pub=20241015 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Exogenous expression of PGC-1α during in vitro maturation impairs the developmental competence of porcine oocytes en-subtitle= kn-subtitle= en-abstract= kn-abstract=Objectives of the current study were to examine the effects of exogenous expression of PGC-1α, which is a transcription factor responsive for controlling mitochondrial DNA (mtDNA) replication, mitochondria quantity control, mitochondrial biogenesis, and reactive oxygen species (ROS) maintenance, in porcine oocytes during in-vitro maturation (IVM) on the developmental competence, as well as mitochondrial quantity and function. Exogenous over-expression of PGC-1α by injection of the mRNA construct into oocytes 20 h after the start of IVM culture significantly increased the copy number of mtDNA in the oocytes, but reduced the incidences of oocytes matured to the metaphase-II stage after the IVM culture for totally 44 h and completely suppressed the early development in vitro to the blastocyst stage following parthenogenetic activation. The exogenous expression of PGC-1α also significantly induced spindle defects and chromosome misalignments. Furthermore, markedly higher ROS levels were observed in the PGC-1α-overexpressed mature oocytes, whereas mRNA level of SOD1, encoded for a ROS scavenging enzyme, was decreased. These results conclude that forced expression of PGC-1α successfully increase mtDNA copy number but led to increased ROS production, evidently by downregulation of SOD1 gene expression, inducement of spindle aberration/chromosomal misalignment, and consequently reduction in the meiotic and developmental competences of porcine oocytes. en-copyright= kn-copyright= en-aut-name=DoSon Quang en-aut-sei=Do en-aut-mei=Son Quang kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=NguyenHai Thanh en-aut-sei=Nguyen en-aut-mei=Hai Thanh kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=WakaiTakuya en-aut-sei=Wakai en-aut-mei=Takuya kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=FunahashiHiroaki en-aut-sei=Funahashi en-aut-mei=Hiroaki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= affil-num=1 en-affil=Department of Animal Science, Graduate School of Environmental and Life Science, Okayama University kn-affil= affil-num=2 en-affil=Department of Animal Science, Graduate School of Environmental and Life Science, Okayama University kn-affil= affil-num=3 en-affil=Department of Animal Science, Graduate School of Environmental and Life Science, Okayama University kn-affil= affil-num=4 en-affil=Department of Animal Science, Graduate School of Environmental and Life Science, Okayama University kn-affil= en-keyword=Porcine kn-keyword=Porcine en-keyword=Mitochondria kn-keyword=Mitochondria en-keyword=Oocytes kn-keyword=Oocytes en-keyword=PGC-1 alpha kn-keyword=PGC-1 alpha en-keyword=In vitro maturation kn-keyword=In vitro maturation END start-ver=1.4 cd-journal=joma no-vol=226 cd-vols= no-issue= article-no= start-page=158 end-page=166 dt-received= dt-revised= dt-accepted= dt-pub-year=2024 dt-pub=20240915 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=The impact of cumulus cell viability and pre-culture with the healthy cell mass on brilliant cresyl blue (BCB) staining assessment and meiotic competence of suboptimal porcine oocytes en-subtitle= kn-subtitle= en-abstract= kn-abstract=Objectives of the present study were to investigate the characteristics including glucose-6-phosphate dehydrogenase activity, as determined by Brilliant Cresyl Blue (BCB) staining, of suboptimal porcine oocytes and to enhance the meiotic competence of those through pre-culture with cumulus cell masses (CCMs). Percentage of oocyte-cumulus complexes (OCCs) derived from small follicles (SF; <3 mm in diameter) containing the oocytes that were assessed as BCB-negative (BCB-) was significantly higher than those derived from medium follicles (MF; 3?6 mm in diameter). Degrees of dead cumulus cells were significantly higher in OCCs containing BCB- oocytes, regardless of the origin of OCCs (MF vs. SF), than those containing BCB-positive (BCB+) ones. Exposing OCCs containing BCB+ oocytes to the apoptosis inducer, carbonyl cyanide m-chlorophenylhydrazone, for 20 h significantly induced the transition to BCB- and meiotic progression of exposed OCCs were significantly reduced in both SF and MF derived ones. Transit of BCB- oocytes to BCB+ was induced when OCCs were pre-cultured with CCMs of MF derived OCCs containing BCB+ oocytes for 20 h before IVM. This pre-culture also significantly increased the meiotic competence of BCB- oocytes, particularly in SF derived ones. However, reactive oxygen species levels were significantly higher in BCB+ oocytes as compared with BCB- ones, regardless of pre-culture with CCMs, whereas no significant differences were found in the ATP contents among the treatment groups. In conclusion, the BCB result of oocytes could be regulated by the healthy status and content of surrounding cumulus cells and the meiotic competence of suboptimal BCB- porcine oocytes is improved by pre-culture with healthy CCMs. en-copyright= kn-copyright= en-aut-name=FonsekaWanniarachchige Tharindu Lakshitha en-aut-sei=Fonseka en-aut-mei=Wanniarachchige Tharindu Lakshitha kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=DoSon Quang en-aut-sei=Do en-aut-mei=Son Quang kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=VanPhong Ngoc en-aut-sei=Van en-aut-mei=Phong Ngoc kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=NguyenHai Thanh en-aut-sei=Nguyen en-aut-mei=Hai Thanh kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=WakaiTakuya en-aut-sei=Wakai en-aut-mei=Takuya kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= en-aut-name=FunahashiHiroaki en-aut-sei=Funahashi en-aut-mei=Hiroaki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=6 ORCID= affil-num=1 en-affil=Department of Animal Science, Graduate School of Environmental and Life Science, Okayama University kn-affil= affil-num=2 en-affil=Department of Animal Science, Graduate School of Environmental and Life Science, Okayama University kn-affil= affil-num=3 en-affil=Department of Animal Science, Graduate School of Environmental and Life Science, Okayama University kn-affil= affil-num=4 en-affil=Department of Animal Science, Graduate School of Environmental and Life Science, Okayama University kn-affil= affil-num=5 en-affil=Department of Animal Science, Graduate School of Environmental and Life Science, Okayama University kn-affil= affil-num=6 en-affil=Department of Animal Science, Graduate School of Environmental and Life Science, Okayama University kn-affil= en-keyword=Oocytes kn-keyword=Oocytes en-keyword=Meiotic competence kn-keyword=Meiotic competence en-keyword=Brilliant cresyl blue kn-keyword=Brilliant cresyl blue en-keyword=Cumulus cells kn-keyword=Cumulus cells END start-ver=1.4 cd-journal=joma no-vol=20 cd-vols= no-issue=3 article-no= start-page=e20220127 end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2023 dt-pub=2023 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Rapid thawing of frozen bull spermatozoa by transient exposure to 70 °C improves the viability, motility and mitochondrial health en-subtitle= kn-subtitle= en-abstract= kn-abstract=Up to now, the definitive conclusion of the positive effects of rapid transient thawing at higher temperatures for shorter durations has not been obtained yet and is still under discussion due to some contradictory findings and limited assessment of post-thawed parameters. The purpose of the current study was to evaluate the effectiveness of rapid thawing in water at 70 °C by using various post-thawed parameters of frozen bull spermatozoa. Experiment 1, monitoring the change of temperature inside frozen bull straw thawed in water at different temperatures. Experiment 2, evaluation of various post-thawed characteristics of frozen bull spermatozoa thawed in water at different temperatures by using a computer-assisted sperm analysis, flow cytometry and immunocytochemistry. The time it took for the temperature inside the straw to warm up to 15 °C was nearly twice as faster when the straw was thawed in 70 °C water compared with 39 °C. Although there were differences among bulls, viability, motility, and mitochondrial membrane potential of spermatozoa thawed at 70 °C for 8 seconds and stabilized at 39 °C for 52 seconds were significantly higher than those of controls (thawed at 39 °C for 60 seconds) at 0 and 3 h after thawing. Just after thawing, however, there were no differences in acrosome integrity and distribution of phospholipase C zeta1, whereas mitochondrial reactive oxygen species production was significantly lower in spermatozoa thawed at 70 °C. From these results, we conclude that rapid thawing at 70 °C and then stabilization at 39 °C significantly improves viability, motility and mitochondrial health of bull spermatozoa rather than conventional thawing at 39 °C. The beneficial effect of rapid transient thawing could be due to shorter exposure to temperatures outside the physiological range, consequently maintaining mitochondrial health. en-copyright= kn-copyright= en-aut-name=NguyenHai Thanh en-aut-sei=Nguyen en-aut-mei=Hai Thanh kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=DoSon Quang en-aut-sei=Do en-aut-mei=Son Quang kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=AthurupanaRukmali en-aut-sei=Athurupana en-aut-mei=Rukmali kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=WakaiTakuya en-aut-sei=Wakai en-aut-mei=Takuya kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=FunahashiHiroaki en-aut-sei=Funahashi en-aut-mei=Hiroaki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= affil-num=1 en-affil=Department of Animal Science, Graduate School of Environmental and Life Science, Okayama University kn-affil= affil-num=2 en-affil=Department of Animal Science, Graduate School of Environmental and Life Science, Okayama University kn-affil= affil-num=3 en-affil=Department of Animal Science, Graduate School of Environmental and Life Science, Okayama University kn-affil= affil-num=4 en-affil=Department of Animal Science, Graduate School of Environmental and Life Science, Okayama University kn-affil= affil-num=5 en-affil=Department of Animal Science, Graduate School of Environmental and Life Science, Okayama University kn-affil= en-keyword=bull semen kn-keyword=bull semen en-keyword=cryopreservation process kn-keyword=cryopreservation process en-keyword=phospholipase C zeta1 (PLCZ1) kn-keyword=phospholipase C zeta1 (PLCZ1) en-keyword=temperature of thawing kn-keyword=temperature of thawing END start-ver=1.4 cd-journal=joma no-vol=210 cd-vols= no-issue= article-no= start-page=154 end-page=161 dt-received= dt-revised= dt-accepted= dt-pub-year=2023 dt-pub=20231015 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Negative correlations of mitochondrial DNA copy number in commercial frozen bull spermatozoa with the motility parameters after thawing en-subtitle= kn-subtitle= en-abstract= kn-abstract=The purpose of the current study was to investigate the relationship between mitochondrial content of commercial frozen-thawed bull spermatozoa and motility. Firstly, mitochondrial DNA copy number per spermatozoon (MDCN), mitochondrial content (MC), the percentage of spermatozoa with high mitochondrial membrane potential (HMMP), intracellular reactive oxygen species (ROS) and motility parameters of frozen-thawed spermatozoa derived from five bulls were determined by using qPCR, flow cytometry and CASA, respectively, and analyzed the relationships. Results showed that all parameters examined, including MDCN, MC, HMMP, ROS and motility indicators, significantly differed among frozen spermatozoa from different bulls. Both MDCN and MC were negatively correlated with HMMP and motility indicators, but positively with ROS, of course, whereas there was a highly positive relationship between MDCN and MC. Secondly, when MDCN and MC were examined in frozen spermatozoa prepared at different points in the lives of four bulls, those did not correlate overall throughout their lives (1.3?14.3 years old), but did correlate significantly in two sires. From these results, we conclude that MDCN and MC of frozen spermatozoa differ among sires, and are negatively correlated with HMMP and sperm motility parameters, probably due to mitochondrial oxidative stress resulted in the presence of ROS, demonstrating that these appear to be useful markers to assess sires’ spermatozoa. It should be noted that the MDCN and MC of bull spermatozoa may not vary overall with the age of the sire, whereas those changes with age in some individuals and may affect sperm motility. en-copyright= kn-copyright= en-aut-name=NguyenHai Thanh en-aut-sei=Nguyen en-aut-mei=Hai Thanh kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=DoSon Quang en-aut-sei=Do en-aut-mei=Son Quang kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=KobayashiHiroshi en-aut-sei=Kobayashi en-aut-mei=Hiroshi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=WakaiTakuya en-aut-sei=Wakai en-aut-mei=Takuya kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=FunahashiHiroaki en-aut-sei=Funahashi en-aut-mei=Hiroaki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= affil-num=1 en-affil=Department of Animal Science, Graduate School of Environmental and Life Science, Okayama University kn-affil= affil-num=2 en-affil=Department of Animal Science, Graduate School of Environmental and Life Science, Okayama University kn-affil= affil-num=3 en-affil=Okayama Prefectural Center for Animal Husbandry and Research kn-affil= affil-num=4 en-affil=Department of Animal Science, Graduate School of Environmental and Life Science, Okayama University kn-affil= affil-num=5 en-affil=Department of Animal Science, Graduate School of Environmental and Life Science, Okayama University kn-affil= en-keyword=Spermatozoa kn-keyword=Spermatozoa en-keyword=Bulls kn-keyword=Bulls en-keyword=Mitochondrial content kn-keyword=Mitochondrial content en-keyword=Motility kn-keyword=Motility en-keyword=Frozen semen kn-keyword=Frozen semen END start-ver=1.4 cd-journal=joma no-vol=13 cd-vols= no-issue=1 article-no= start-page=13050 end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2023 dt-pub=20230811 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Photo-dependent cytosolic delivery of shRNA into a single blastomere in a mouse embryo en-subtitle= kn-subtitle= en-abstract= kn-abstract=Single-cell-specific delivery of small RNAs, such as short hairpin RNA (shRNA) and small noncoding RNAs, allows us to elucidate the roles of specific upregulation of RNA expression and RNAi-mediated gene suppression in early embryo development. The photoinduced cytosolic dispersion of RNA (PCDR) method that we previously reported can introduce small RNAs into the cytosol of photoirradiated cells and enable RNA delivery into a single-cell in a spatiotemporally specific manner. However, the PCDR method has only been applied to planer cultured cells and not to embryos. This study demonstrated that the PCDR method can be utilized for photo-dependent cytosolic shRNA delivery into a single blastomere and for single blastomere-specific RNA interference in mouse embryos. Our results indicate that PCDR is a promising approach for studying the developmental process of early embryogenesis. en-copyright= kn-copyright= en-aut-name=IkawaYuka en-aut-sei=Ikawa en-aut-mei=Yuka kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=WakaiTakuya en-aut-sei=Wakai en-aut-mei=Takuya kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=FunahashiHiroaki en-aut-sei=Funahashi en-aut-mei=Hiroaki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=SoeTet Htut en-aut-sei=Soe en-aut-mei=Tet Htut kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=WatanabeKazunori en-aut-sei=Watanabe en-aut-mei=Kazunori kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= en-aut-name=OhtsukiTakashi en-aut-sei=Ohtsuki en-aut-mei=Takashi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=6 ORCID= affil-num=1 en-affil=Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University kn-affil= affil-num=2 en-affil=Department of Animal Science, Graduate of Environmental and Life Science, Okayama University kn-affil= affil-num=3 en-affil=Department of Animal Science, Graduate of Environmental and Life Science, Okayama University kn-affil= affil-num=4 en-affil=Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University kn-affil= affil-num=5 en-affil=Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University kn-affil= affil-num=6 en-affil=Department of Interdisciplinary Science and Engineering in Health Systems, Okayama University kn-affil= END start-ver=1.4 cd-journal=joma no-vol=465 cd-vols= no-issue= article-no= start-page=012001 end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2020 dt-pub=2020 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Animal Biotechnology Roles in Livestock Production en-subtitle= kn-subtitle= en-abstract= kn-abstract=Currently, meat and milk productions are significantly increasing especially in Asia. The supply of these products is vital to people's health and well-being, whereas the efficiency of beef production appears to be still lower than other meat productions. Improvements in the quality and functionality of their livestock products, as well as their production efficiency, are required for further production. Animal biotechnologies have contributed to genetic improvement, genetic diversity maintenance of domestic animals, etc. Basic animal biotechnologies, such as artificial insemination and embryo transfer, have been well established and applied as powerful tools for genetic improvement of livestock. In the applications of artificial insemination techniques, the use of sexed semen has been now widely spread, and also efforts are also made in the development of the technology using a small amount of sperm. For embryo transfer, several types of vitrification technologies have been applied to improve pregnancy rates and contributed to the international/domestic supply of livestock embryos. Conventional animal biotechnologies, such as in vitro fertilization and intracellular sperm injection, have been applied to not only livestock production and also human-assisted reproductive medicine. For in-vitro production of embryos in domestic animals, currently, oocytes have been collected from medium or large follicles (3-6 mm or larger in diameter) of ovaries. Although the oocytes derived from small follicles (less than 3 mm in diameter) exist more on the surface of ovaries, the developmental competence of the oocytes has been known to be significantly lower than those from medium follicles. If we could improve the competence of oocytes derived from small follicles significantly, we may be able to increase the number of female gamete resources for in vitro embryo production. Also, the development of techniques for producing transgenic and cloned animals has greatly contributed to the creation of pharmaceuticals and organs for xenotransplantation. Recently, furthermore, genome editing technologies, such as combined use of CRISPR/Cas9 and PiggyBac, have been developed and have made it possible to correct specific parts of the genome and introduce mutations by homologous recombination. In this review, I would like to discuss the application and progress of the above biotechnologies, including our recent research results. en-copyright= kn-copyright= en-aut-name=FunahashiHiroaki en-aut-sei=Funahashi en-aut-mei=Hiroaki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= affil-num=1 en-affil=Department of Animal Science, Graduate School of Environmental and Life Science, Okayama University kn-affil= END start-ver=1.4 cd-journal=joma no-vol=57 cd-vols= no-issue=1 article-no= start-page=163 end-page=167 dt-received= dt-revised= dt-accepted= dt-pub-year=2010 dt-pub=20101012 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Hydrophobic Silicone Elastomer Chamber for Recording Trajectories of Motile Porcine Sperms without Adsorption en-subtitle= kn-subtitle= en-abstract= kn-abstract=Motile porcine sperms adhere to hydrophilic materials such as glass and plastics. The adsorption of sperms to a hydrophobic poly(dimethylsiloxane) (PDMS) membrane is less compared with that to glass. We investigated the linear velocity (LV) and amplitude of lateral head displacement (ALHD) of motile porcine sperm on glass and PDMS preparations using computer-assisted sperm analysis (CASA). Significant decreases were observed in the 15-min LV (P<0.05) and ALHD (P<0.05) in motile porcine sperm on glass preparations compared with those on PDMS preparations. These differences were due to adsorption of the head and/or neck to hydrophilic substrates. Because of the elasticity of PDMS, we propose that a PDMS membrane should be used for CASA. To investigate the dynamics of motile porcine sperms with microfluidics, we do not recommend plasma treatment to bond PDMS and glass in the microchannel preparation; instead, we suggest that a PDMS molding process without plasma treatment be used for preparation of microfluidic channels. en-copyright= kn-copyright= en-aut-name=MatsuuraKoji en-aut-sei=Matsuura en-aut-mei=Koji kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=KurodaYuka en-aut-sei=Kuroda en-aut-mei=Yuka kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=YamashitaKeisuke en-aut-sei=Yamashita en-aut-mei=Keisuke kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=FunahashiHiroaki en-aut-sei=Funahashi en-aut-mei=Hiroaki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= affil-num=1 en-affil= kn-affil=Research Core for Interdisciplinary Sciences, Okayama University affil-num=2 en-affil= kn-affil=Research Core for Interdisciplinary Sciences, Okayama University affil-num=3 en-affil= kn-affil=Department of Animal Science, Faculty of Agriculture, Okayama University affil-num=4 en-affil= kn-affil=Department of Animal Science, Faculty of Agriculture, Okayama University en-keyword=Adsorption kn-keyword=Adsorption en-keyword=Porcine sperm motility kn-keyword=Porcine sperm motility en-keyword=Silicone elastomer kn-keyword=Silicone elastomer en-keyword=Trajectories kn-keyword=Trajectories END start-ver=1.4 cd-journal=joma no-vol=74 cd-vols= no-issue=5 article-no= start-page=863 end-page=870 dt-received= dt-revised= dt-accepted= dt-pub-year=2010 dt-pub=20100915 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Application of a microfluidic sperm sorter to the in-vitro fertilization of porcine oocytes reduced the incidence of polyspermic penetration en-subtitle= kn-subtitle= en-abstract= kn-abstract=The objective of this study was to use a microfluidic sperm sorter (MFSS), designed to isolate motile human spermatozoa with laminar flows (no centrifugation), for porcine IVF. Boar spermatozoa were diluted at 1 x 10(8) with a diluent containing 20% seminal fluid and flowed with modified TCM-199 (mM199, with 5 mM caffeine) to introduce motile sperm into the exit chamber for IVF. In Experiment 1, after flowing for 5 min, sperm concentration varied significantly among specific sites within the MFSS collecting chamber (range, 0.8 +/- 0.5 x 10(4) to 575.0 +/- 56.3 x 10(4) cells/mL; mean +/- SEM). In Experiment 2, when porcine IVM oocytes were placed at three locations in the MFSS exit chamber (where only motile spermatozoa accumulated) and subsequently cultured in caffeine-free mM199 for 8 h, sperm penetration rate was not significantly different among places (86.1 +/- 10.5 to 100%), but the monospermic penetration rate was lower (P < 0.05) in oocytes 3.5 mm from the exit position (12.5 +/- 4.8%) than those at 7.5 mm (53.1 +/- 6.0%) or further (41.9 +/- 2.8%) from the exit. In Experiment 3, the normal fertilization index (ratio of monospermic oocytes to number of oocytes examined) 8 h after insemination was higher (P < 0.05) in the MFSS-IVF system (0.375 +/- 0.040) than both standard IVF and transient IVF (0.222 +/- 0.028 and 0.189 +/- 0.027, respectively, with co-culture for 8 h and for 5 min). Developmental competence of fertilized oocytes (blastocyst formation) was higher (P < 0.05) in the MFSS-IVF system (40.9 +/- 2.3%) than in either standard or transient IVF (22.6 +/- 1.4 and 33.7 +/- 3.5%). In conclusion, brief co-culture of porcine oocytes with spermatozoa gradually accumulated in the MFSS chamber improved the efficiency of producing monospermic fertilized embryos and blastocysts. Furthermore, efficiencies were significantly affected by oocyte location within the chamber. en-copyright= kn-copyright= en-aut-name=SanoHikaru en-aut-sei=Sano en-aut-mei=Hikaru kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=MatsuuraKoji en-aut-sei=Matsuura en-aut-mei=Koji kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=NaruseKeiji en-aut-sei=Naruse en-aut-mei=Keiji kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=FunahashiHiroaki en-aut-sei=Funahashi en-aut-mei=Hiroaki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= affil-num=1 en-affil= kn-affil=Department of Animal Science, Graduate school of Natural Science and Technology, Okayama University affil-num=2 en-affil= kn-affil=Cardiovascular Physiology, Graduate school of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University affil-num=3 en-affil= kn-affil=Cardiovascular Physiology, Graduate school of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University affil-num=4 en-affil= kn-affil=Department of Animal Science, Graduate school of Natural Science and Technology, Okayama University en-keyword=Oocytes kn-keyword=Oocytes en-keyword=Polyspermy kn-keyword=Polyspermy en-keyword=IVF kn-keyword=IVF en-keyword=Sperm sorter kn-keyword=Sperm sorter en-keyword=Pig kn-keyword=Pig END start-ver=1.4 cd-journal=joma no-vol=56 cd-vols= no-issue=5 article-no= start-page=552 end-page=557 dt-received= dt-revised= dt-accepted= dt-pub-year=2010 dt-pub=201010 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=In-vitro Culture with a Tilting Device in Chemically Defined Media During Meiotic Maturation and Early Development Improves the Quality of Blastocysts Derived from In-vitro Matured and Fertilized Porcine Oocytes en-subtitle= kn-subtitle= en-abstract= kn-abstract=Under physiological conditions, mammalian oocytes and embryos appear to be stimulated not only chemically but also mechanically, such as by compression, shear stress and/or friction force in the follicle and female reproductive tract. The present study was undertaken to examine the effects of kinetic culture with a tilting device in chemically defined media during in vitro maturation (IVM) of porcine oocytes and in vitro culture (IVC) following in vitro fertilization (IVF) on the early developmental competence and quality of blastocysts. After culture in a chemically defined IVM medium, modified porcine oocyte medium (mPOM) containing gonadotropins and dibutyryl cAMP for 20 h, the mean diameter of the cumulus-oocyte complexes (COCs) was larger in the tilting culture than in the static controls, whereas the diameter of the oocytes did not differ. When culture of the COCs was continued additionally in a fresh medium without gonadotropins and dibutyryl cAMP for 24 h, the incidences of oocytes completing GVBD and developing to the metaphase-II stage did not differ between the tilting and static culture systems. Furthermore, the sperm penetration after IVF and developmental competence of the oocytes to the blastocyst stage were not different between the tilting and static systems during IVM and IVC. However, tilting culture during both IVM and IVC had a significant positive effect on the number of cells per blastocyst (P<0.05). These observations indicate that tilting culture during IVM and IVC in chemically defined media improves the quality of blastocyst, as determined by the number of cells per blastocyst, without any effects on penetrability and developmental competence. en-copyright= kn-copyright= en-aut-name=KoikeTakayuki en-aut-sei=Koike en-aut-mei=Takayuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=MatsuuraKoji en-aut-sei=Matsuura en-aut-mei=Koji kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=NaruseKeiji en-aut-sei=Naruse en-aut-mei=Keiji kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=FunahashiHiroaki en-aut-sei=Funahashi en-aut-mei=Hiroaki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= affil-num=1 en-affil= kn-affil=Department of Animal Science, Graduate School of Natural Science and Technology, Okayama University affil-num=2 en-affil= kn-affil=Research Core for Interdisciplinary Sciences, Okayama University affil-num=3 en-affil= kn-affil=Department of Cardiovascular Physiology, Graduate school of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University affil-num=4 en-affil= kn-affil=Department of Animal Science, Graduate School of Natural Science and Technology, Okayama University en-keyword=Inclining device kn-keyword=Inclining device en-keyword=In vitro culture kn-keyword=In vitro culture en-keyword=In vitro fertilization kn-keyword=In vitro fertilization en-keyword=Oocytes kn-keyword=Oocytes en-keyword=Pig kn-keyword=Pig END start-ver=1.4 cd-journal=joma no-vol=33 cd-vols= no-issue= article-no= start-page=7 end-page=11 dt-received= dt-revised= dt-accepted= dt-pub-year=2011 dt-pub=20110401 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=津高牧場への発情発見システム｢牛歩｣の導入と今後の課題 en-subtitle= kn-subtitle= en-abstract= kn-abstract= en-copyright= kn-copyright= en-aut-name= en-aut-sei= en-aut-mei= kn-aut-name=舟橋弘晃 kn-aut-sei=舟橋 kn-aut-mei=弘晃 aut-affil-num=1 ORCID= en-aut-name= en-aut-sei= en-aut-mei= kn-aut-name=野久保隆 kn-aut-sei=野久保 kn-aut-mei=隆 aut-affil-num=2 ORCID= en-aut-name= en-aut-sei= en-aut-mei= kn-aut-name=片山佳司 kn-aut-sei=片山 kn-aut-mei=佳司 aut-affil-num=3 ORCID= affil-num=1 en-affil= kn-affil=岡山大学大学院自然科学研究科 affil-num=2 en-affil= kn-affil=岡山大学農学部附属山陽圏フィールド科学センター affil-num=3 en-affil= kn-affil=岡山大学農学部附属山陽圏フィールド科学センター END start-ver=1.4 cd-journal=joma no-vol= cd-vols= no-issue= article-no= start-page= end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2008 dt-pub=20081015 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Effect of glucose and pyruvate on nuclear and cytoplasmic maturation of porcine oocytes in a chemically defined medium en-subtitle= kn-subtitle= en-abstract= kn-abstract=

The objective was to examine potential roles of glucose and pyruvate in nuclear and cytoplasmic maturation of porcine oocytes. Oocyte-cumulus complexes (OCC), derived from 3 to 6 mm follicles, were cultured in a chemically defined medium (pyruvate-free mNCSU37-PVA), with or without 5.55 mM glucose, during in vitro maturation (IVM); in the absence of glucose, germinal vesicle breakdown (GVBD) and nuclear maturation were prevented (P < 0.05). Subsequently, OCC were cultured for IVM in glucose-containing mNCSU37-PVA supplemented with 6-amononicotinamide (6-AN) and diphenyleneiodonium (DPI), inhibitors of the pentose phosphate pathway (PPP); both compounds (>= 10 mu M 6-AN and >= 10 nM DPI) inhibited resumption of meiosis (P < 0.05). Supplementation of glucose-free maturation medium with increasing concentrations of pyruvate induced resumption of meiosis and increased the incidence of oocytes reaching metaphase-II in a concentration-dependent manner (P < 0.05). More mature oocytes were obtained in the presence of pyruvate + glucose (P < 0.05). After culture to allow maturation, glutathione content was higher in oocytes cultured in the presence of pyruvate alone than in those cultured in glucose alone; inclusion of 6-AN abolished responses to pyruvate (P < 0.05). In conclusion, both glucose and pyruvate played a critical role in the release of porcine oocytes from arrest at the GV-I stage, probably through the PPP, whereas supplementation with pyruvate improved cytoplasmic maturation, as determined by oocyte glutathione content.

en-copyright= kn-copyright= en-aut-name=FunahashiHiroaki en-aut-sei=Funahashi en-aut-mei=Hiroaki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=KoikeTakayuki en-aut-sei=Koike en-aut-mei=Takayuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=SakaiRyoko en-aut-sei=Sakai en-aut-mei=Ryoko kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= affil-num=1 en-affil= kn-affil=Department of Animal Science, Okayama University affil-num=2 en-affil= kn-affil=Department of Animal Science, Okayama University affil-num=3 en-affil= kn-affil=Department of Animal Science, Okayama University en-keyword=in vitro maturation kn-keyword=in vitro maturation en-keyword=oocyte kn-keyword=oocyte en-keyword=glucose kn-keyword=glucose en-keyword=pyruvg kn-keyword=pyruvg en-keyword=pig kn-keyword=pig END start-ver=1.4 cd-journal=joma no-vol=87 cd-vols= no-issue=1 article-no= start-page=205 end-page=214 dt-received= dt-revised= dt-accepted= dt-pub-year=1998 dt-pub=199802 dt-online= en-article= kn-article= en-subject= kn-subject= en-title=前核形成および初期胚発生に関係する豚卵胞卵子の細胞質成熟 kn-title=Cytoplasmic Maturation of Porcine Oocytes for Successful Male Pronuclear Formation and Early Embryonic Development en-subtitle= kn-subtitle= en-abstract=豚受精卵の体外生産を成功させるためには、体外成熟、体外受精および対外発生に必要な効率的な一連の技術の積み重ねが必要である。本総説は、効率的な豚受精卵の体外生産に関係する体外成熟中の諸要因について論じる。長い間、体外成熟卵子の体外受精後の雄性前核の形成不全は、体外受精卵を生産するための深刻な問題として、多くの研究者によって長い間研究されてきた。しかし現在では、雄性前核形成に関するこの問題は、すでに解決され、主に体外成熟中の酸化ストレスが原因であると考えられている。さらに最近、体外成熟・受精卵の初期発生能力は、卵成熟期間中の培養条件の改善を通じて飛躍的に改善されており、現在では、豚受精卵の初期発生に影響をおよぼす卵子成熟中の諸要因について研究によって、産業的に利用可能な胚盤胞受精卵作用効率およ産仔の生産効率が得られている。体外成熟可能な卵胞卵子は、通常春機発動以前の屠畜雌豚の卵巣に存在する中型成熟卵胞から回収されている。そこで、今後の研究において、春機発動以前の雌豚および性成熟を経た雌豚のそれぞれに存在する卵胞卵子の発生能力に影響をおぼす要因のさらなる理解が必要とされる。 kn-abstract=Successful in vitro production of production of porcine embryos requires a series of integrated, effective techniques for in vitro maturation (IVM), in vitro fertilization (IVF) and in vitro culture (IVC). This paper reviews about cytoplasmic maturation associated with the efficiency of in vitro production of porcine embryos. Traditionally, the failure to from a male pronucleus have been reported as serious problems in producing porcine emabryos following IVM and IVF. The problem of male pronuclear formation is currently considered to be mainly due to oxidative stress during IVM. More recently the developmental competence of embryos following IVM and IVF has been investigated through improvement of culture conditions for oocyte maturation. Currently, an acceptable rate of blastocyst formation and the birth of live piglets has been achieved by investigating affecting factors during IVM, IVF and IVC of porcine oocytes. Since the ovarian oocytes available for IVM are primarily those present in mid-size antral follicles of prepuberal gilts, more research is needed to gain an improved understanding of the factors associated with the developmental competence in oocytes from both preantral and antral follicles. en-copyright= kn-copyright= en-aut-name=FunahashiHiroaki en-aut-sei=Funahashi en-aut-mei=Hiroaki kn-aut-name=舟橋弘晃 kn-aut-sei=舟橋 kn-aut-mei=弘晃 aut-affil-num=1 ORCID= affil-num=1 en-affil= kn-affil=岡山大学 en-keyword=pig kn-keyword=pig en-keyword=oocyte kn-keyword=oocyte en-keyword=maturation kn-keyword=maturation en-keyword=fertilization kn-keyword=fertilization en-keyword=developmental competence kn-keyword=developmental competence END start-ver=1.4 cd-journal=joma no-vol= cd-vols= no-issue= article-no= start-page= end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=1990 dt-pub=19900328 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=哺乳動物初期胚における核移植に関する研究 en-subtitle= kn-subtitle= en-abstract= kn-abstract= en-copyright= kn-copyright= en-aut-name= en-aut-sei= en-aut-mei= kn-aut-name=舟橋弘晃 kn-aut-sei=舟橋 kn-aut-mei=弘晃 aut-affil-num=1 ORCID= affil-num=1 en-affil= kn-affil=岡山大学 END