Time filter

Source Type

Chasombat J.,Khon Kaen University | Nagai T.,Food and Fertilizer Technology Center | Nagai T.,Japan National Agriculture and Food Research Organization | Parnpai R.,Suranaree University of Technology | Vongpralub T.,Khon Kaen University
Cryobiology | Year: 2015

The stabilization of spindle fibersis important for successful vitrification of bovine oocytes because microtubules and other cytoskeleton fibers (CSF) can be damaged during vitrification, resulting in failure of fertilization after thawing. Docetaxel, a stabilizing agent, could potentially reduce CSF damage of bovine oocytes induced during vitrification. However, there have been no reports on the effects of docetaxel on their vitrification. Experiment 1 was conducted to investigate the effects of various doses of docetaxel (0.0, 0.05, 0.5, 5.0 and 50. μM) in preincubation medium of in vitro matured (IVM) bovine oocytes on their developmental ability after in vitro fertilization (IVF). The results show that 0.05. μM docetaxel had no adverse effect on embryo development, while docetaxel at a concentration of ≥0.5. μM inhibited development. Experiments 2 and 3 were conducted to investigate the effects of preincubation of IVM bovine oocytes with 0.05. μM docetaxel for 30. min prior to vitrification-warming on CSF integrity (Experiment 2), and on oocyte survival and viability after IVF (Experiment 3). When preincubated with 0.05. μM docetaxel for 30. min before vitrification, post-thawed oocytes had less CSF damage and higher survival rates compared with those untreated with docetaxel before vitrification. Surviving oocytes also had higher rates of cleavage and development to the blastocyst stage after IVF. In conclusion, preincubation of IVM bovine oocytes with 0.05. μM docetaxel for 30. min before vitrification was effective at preventing CSF damage during vitrification, and improving oocyte viability after warming and subsequent cleavage and blastocyst formation after IVF. © 2015 Elsevier Inc. Source

Punyawai K.,Suranaree University of Technology | Punyawai K.,National Livestock Breeding Center | Anakkul N.,National Livestock Breeding Center | Anakkul N.,Chulalongkorn University | And 9 more authors.
Journal of Reproduction and Development | Year: 2015

This study was designed to compare the efficiency of the Cryotop method and that of two methods that employ a micro volume air cooling (MVAC) device by analyzing the survival and development of bovine oocytes and blastocysts vitrified using each method. In experiment I, in vitro-matured (IVM) oocytes were vitrified using an MVAC device without direct contact with liquid nitrogen (LN2; MVAC group) or directly plunged into LN2 (MVAC in LN2 group). A third group of IVM oocytes was vitrified using a Cryotop device (Cryotop group). After warming, vitrified oocytes were fertilized in vitro. There were no significant differences in cleavage and blastocyst formation rates among the three vitrified groups, with the rates ranging from 53.1% to 56.6% and 20.0% to 25.5%, respectively; however, the rates were significantly lower (P < 0.05) than those of the fresh control group (89.3% and 43.3%, respectively) and the solution control group (87.3% and 42.0%, respectively). In experiment II, in vitro-produced (IVP) expanded blastocysts were vitrified using the MVAC, MVAC in LN2 and Cryotop methods, warmed and cultured for survival analysis and then compared with the solution control group. The rate of development of vitrified-warmed expanded blastocysts to the hatched blastocyst stage after 24 h of culture was lower in the MVAC in LN2 group than in the solution control group; however, after 48–72 h of culture, the rates did not significantly differ between the groups. These results indicate that the MVAC method without direct LN2 contact is as effective as the standard Cryotop method for vitrification of bovine IVM oocytes and IVP expanded blastocysts. © 2015 by the Society for Reproduction and Development. Source

Takahashi T.,Akita | Sasaki K.,Akita | Somfai T.,Japan National Agriculture and Food Research Organization | Nagai T.,Food and Fertilizer Technology Center | And 3 more authors.
Journal of Reproduction and Development | Year: 2016

The antioxidant effect of N, N-dimethylglycine (DMG) on in vitro-produced (IVP) bovine embryos was examined. After in vitro fertilization, presumptive zygotes were cultured with or without 0.1 µM DMG under different oxygen tensions. The percentage of embryos developing to the blastocyst stage was lowest under a 20% oxygen concentration without DMG, and it was significantly increased (P < 0.05) by applying a 5% oxygen concentration. Under the 20% oxygen concentration, supplementation of the medium with DMG significantly improved blastocyst development, which was nearly equal to that achieved under 5% oxygen without DMG. Furthermore, a tendentious increase (P = 0.06) in blastocyst cell numbers was observed when DMG was applied. In the second experiment, addition of H2O2 (0.5 mM) to the culture medium significantly (P < 0.01) reduced the percentage of embryos developing to the blastocyst stage. However, DMG supplementation prevented this reduction. In conclusion, DMG enhanced the in vitro development of IVP bovine embryos by acting as an antioxidant. © 2016 by the Society for Reproduction and Development. Source

Somfai T.,Japan National Agriculture and Food Research Organization | Yoshioka K.,Japanese National Institute of Animal Health | Tanihara F.,Japan National Institute of Agrobiological Science | Tanihara F.,Yamaguchi University | And 6 more authors.
PLoS ONE | Year: 2014

We report the successful piglet production from cryopreserved oocytes for the first time by using a simple, high capacity vitrification protocol for preservation and a defined system for in vitro embryo production. Immature cumulus-oocyte complexes (COCs) from prepubertal gilts were vitrified in microdrops and stored in liquid nitrogen. After warming, COCs were subjected to in vitro maturation (IVM), fertilization (IVF), and subsequent culture (IVC). Adjusting warmplate temperature to 42°C during warming prevented temperature drops in a medium below 34.0°C and significantly increased the percentage of oocyte survival and thus blastocyst yields obtained from total vitrified oocytes compared with that of warming at 38°C (87.1% vs 66.9% and 4.4% vs 2.7%, respectively). Nuclear maturation and fertilization of oocytes were not affected by vitrification and warming temperature. Blastocyst development on day 7 (day 0 = IVF) of the surviving oocytes after warming at 38°C and 42°C was not different but lower (P<0.05) than those of non-vitrified control oocytes (4.6%, 5.2% and 17.9%, respectively). However, blastocyst cell numbers in the control and vitrified groups were similar irrespective of warming temperature. Omitting porcine follicular fluid (pFF) from IVM medium (POM) did not affect maturation, fertilization and embryo development of vitrified-warmed oocytes. Transfer of blastocysts obtained on day 5 from vitrified oocytes matured either with or without pFF into 4 recipients (2 for each group) resulted in 4 pregnancies and the delivery of a total of 18 piglets. In conclusion, optimization of warming temperature was a key factor for achieving high survival rates, and surviving oocytes could be utilized in vitro using defined media. Using these modifications, live piglets could be obtained from cryopreserved oocytes for the first time. © 2014 Somfai et al. Source

Lee C.-F.,Agricultural Research Institute | Chang H.-Y.,Tainan District Agricultural Research and Extension Station | Wang C.-L.,Agricultural Research Institute | Chen W.-S.,Food and Fertilizer Technology Center
Zoological Studies | Year: 2011

A review of Phyllotreta Chevrolat in Taiwan (Coleoptera: Chrysomelidae: Galerucinae: Alticini). Zoological Studies 50(4): 525-533. Species of the genus Phyllotreta Chevrolat in Japan and Taiwan are reviewed. Phyllotreta striolata (Fabricius) is redescribed based on Taiwanese specimens; P. chotanica Duvivier is recorded for the 1st time in Taiwan; and P. downesi insularis Heikertinger is raised to species level. Lectotypes and paratypes are designated for P. downesi insularis. Source

Discover hidden collaborations