scholarly journals Blastocyst formation, embryo transfer and breed comparison in the first reported large scale cloning of camels

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
P. O. Olsson ◽  
A. H. Tinson ◽  
N. Al Shamsi ◽  
K. S. Kuhad ◽  
R. Singh ◽  
...  
Keyword(s):  
Embryo Transfer ◽  
Nuclear Transfer ◽  
Large Scale ◽  
Donor Cell ◽  
Blastocyst Formation ◽  
Short Term ◽  
Embryo Formation ◽  
Large Expansion ◽  
Breed Differences ◽  
Breed Comparison

AbstractCloning, through somatic cell nuclear transfer (SCNT), has the potential for a large expansion of genetically favorable traits in a population in a relatively short term. In the present study we aimed to produce multiple cloned camels from racing, show and dairy exemplars. We compared several parameters including oocyte source, donor cell and breed differences, transfer methods, embryo formation and pregnancy rates and maintenance following SCNT. We successfully achieved 47 pregnancies, 28 births and 19 cloned offspring who are at present healthy and have developed normally. Here we report cloned camels from surgical embryo transfer and correlate blastocyst formation rates with the ability to achieve pregnancies. We found no difference in the parameters affecting production of clones by camel breed, and show clear differences on oocyte source in cloning outcomes. Taken together we demonstrate that large scale cloning of camels is possible and that further improvements can be achieved.

Porcine somatic cell nuclear transfer donor sources affect transplant success: A meta-analysis

2018 ◽  
Author(s):  
Zhenhua Guo ◽  
Lei Lv ◽  
Di Liu ◽  
Zhongqiu Li
Keyword(s):  
Somatic Cell ◽  
Somatic Cell Nuclear Transfer ◽  
Nuclear Transfer ◽  
Meta Analysis ◽  
Donor Cell ◽  
Blastocyst Formation ◽  
Embryo Viability ◽  
Live Births ◽  
Reconstructed Embryo

Herd boars, male domestic pigs used for stud, are economically important, and somatic cell nuclear transfer (SCNT) is a promising technology to expand herd boar yields. However, live births are dictated by donor cell source, and fetal donors may offer more advantages than adult donors. A meta-analysis was conducted to better understand how donor sources affect SCNT outcomes. Of the 1,431 records viewed, 10 were selected for review. Blastocyst formation rates, successful pregnancies, and live births were assessed to measure efficacy. SCNT blastocyst formation differed between adult and fetal donors among the studies. SCNT pigs had more malformed fetuses as well, which negatively affected the post-birth mortality. Organs of porcine fetuses are limited by deficiencies of maternal nutrient and growth hormones, which compromise post-birth adaptations. SCNT pregnancy success is neither determined by donor source nor by live births. Live births are also tied to donor age. Embryos from fetal donors are more frequently healthy likely due to less differentiation and less reprogramming of reconstructed embryos. Adult donors in contrast have more cell differentiation and as such accumulate more mutations and damage. This may reduce reconstructed embryo viability. Finally, SCNT efficiency may be improved with more in vitro passages, but more work is required to validate this concept.

20 Aggregation of yak heterospecific somatic cell nuclear transfer embryos improves cloning efficiency

2020 ◽  
Vol 32 (2) ◽  
pp. 135
Author(s):  
M. Yauri Felipe ◽  
M. Duque Rodríguez ◽  
A. De Stéfano ◽  
D. Salamone
Keyword(s):  
Somatic Cell ◽  
Somatic Cell Nuclear Transfer ◽  
Nuclear Transfer ◽  
Bos Taurus ◽  
Formation Rate ◽  
Donor Cell ◽  
Blastocyst Formation ◽  
Fluid Medium ◽  
Exact Test ◽  
Significant Difference

Cloning endangered species has the limitation that generally the number of available oocytes is limited. Reprogramming the nuclei heterospecifically using an enucleated oocyte from a different species is an alternative. Aggregation of SCNT (somatic cell nuclear transfer) embryos from the same specie results in improved embryo development. However, after aggregation of heterospecific SCNT embryos from different genera, no effects were observed (Moro et al. 2015 Reproduction 50, 1-10). The objective of this study was to evaluate the influence of aggregation of yak (Bos grunniens) embryos produced by heterospecific SCNT using enucleated oocytes from an animal from the same genus Bos taurus. As control homospecific SCNT of Bos taurus, parthenogenic zone-free embryos and IVF embryos were used. Cumulus-oocyte complexes were recovered from bovine slaughterhouse ovaries by follicular aspiration. The cumulus-oocyte complexes were matured in tissue culture medium 199 containing 10% fetal bovine serum, 10μgmL−1 FSH, 0.3mM sodium pyruvate, 100mM cysteamine, and 2% antibiotic-antimycotic for 22h, at 6.5% CO2 in humidified air and 38.5°C. After denudation, mature oocytes were stripped of the zona pellucida using a protease and then enucleated by micromanipulation. Staining was performed with Hoechst 33342 to observe MII. Enucleated oocytes were placed in phytohemagglutinin to induce adherence with the donor cell followed by electrofusion. All reconstituted embryos were activated using ionomcine. This was followed by a treatment with 6-dimethylaminopurine for 3h. Zona-free reconstituted cloned embryos were cultured in the wells of the well system, placing one (1×) or two (2×) per microwell, in synthetic oviductal fluid medium. The experimental groups were parthenogenic zone free; IVF; reconstituted embryos bull fibroblast-enucleated oocyte from cow (BC1×); reconstituted embryos yak fibroblast-enucleated oocyte from cow (YC1×); and reconstituted embryos aggregated yak fibroblast-enucleated oocyte from cow (YC2×). In all experimental groups, cleavage of at least one embryo in the wells and blastocyst formation at Day 7 were assessed. The effect of cloned embryo aggregation on blastocyst rates was analysed using Fisher exact tests (GraphPad Prisma 8), and results are shown on Table 1. Results demonstrated that aggregation of two SCNT heterospecific embryos increased the blastocyst formation rate of yak (P<0.05). In conclusion aggregation in yak heterospecific SCNT embryos from species of the same genus (Bos) can improve development to blastocyst. Table 1.Aggregation of yak heterospecific somatic cell nuclear transfer embryos Experimental group1 No. of embryos No. of embryos-wells2 Cleavage (%) Blastocyst (%) PZF 68 68 66 (97.06%)a 17 (25.00%)acd IVF 89 - 81 (91.01%)ab 39 (43.82%)b BC1× 45 45 41 (91.11%)b 6 (13.33%)cd YC1× 101 101 77 (76.24%)c 14 (13.86%)c YC2× 134 67 61 (91.04%)ab 21 (31.34%)ab a-dDifferent superscripts in the same column indicate significant difference (Fisher's exact test, P<0.05). 1PZF, parthenogenetic zone free; IFV, IVF fecundation; BC1×, clone of bovine; YC1×, clone of yak-bovine; YC2×, clone of yak-bovine added. 2Wells used with embryos.

scholarly journals Cats cloned from fetal and adult somatic cells by nuclear transfer

Reproduction ◽  
2005 ◽  
Vol 129 (2) ◽  
pp. 245-249 ◽  
Author(s):  
X J Yin ◽  
H S Lee ◽  
Y H Lee ◽  
Y I Seo ◽  
S J Jeon ◽  
...  
Keyword(s):  
Embryo Transfer ◽  
Nuclear Transfer ◽  
Cell Mass ◽  
Somatic Cells ◽  
Donor Cell ◽  
Fibroblast Cells ◽  
Fetal Fibroblast ◽  
Skin Cells ◽  
Fetal Fibroblasts ◽  
Adult Skin

This work was undertaken in order to study the developmental competence of nuclear transfer (NT ) into cat embryos using fetal fibroblast and adult skin fibroblast cells as donor nuclei. Oocytes were recovered by mincing the ovaries in Hepes-buffered TCM199 and selecting the cumulus oocyte complexes (COCs) with compact cumulus cell mass and dark color. Homogenous ooplasm was cultured for maturation in TCM199+10% fetal bovine serum (FBS) for 12 h and used as a source of recipient cytoplast for exogenous somatic nuclei. In experiment 1, we evaluated the effect of donor cell type on the reconstruction and development of cloned embryos. Fusion, first cleavage and blastocyst developmental rate were not different between fetal fibroblasts and adult skin cells (71.2 vs 66.8; 71.0 vs 57.6; 4.0 vs 6.1% respectively; P < 0.05). In experiment 2, cloned embryos were surgically transferred into the oviducts of recipient queens. One of the seven recipient queens was delivered naturally of 2 healthy cloned cats and 1 stillborn from fetal fibroblast cells of male origin 65 days after embryo transfer. One of three recipient queens was delivered naturally of 1 healthy cloned cat from adult skin cells of female origin 65 days after embryo transfer. The cloned cats showed genotypes identical to the donor cell lines, indicating that adult somatic cells can be used for feline cloning.

52 THE EFFECTS OF DONOR CELL CYCLE AND THE TIMING OF OOCYTE ACTIVATION ON DEVELOPMENT OF BOVINE NUCLEAR TRANSFERRED EMBRYOS IN VIVO

2011 ◽  
Vol 23 (1) ◽  
pp. 132 ◽  
Author(s):  
K. Matsukawa ◽  
S. Akagi ◽  
K. Fukunari ◽  
Y. Hosokawa ◽  
C. Yonezawa ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Embryo Transfer ◽  
Formation Rate ◽  
Donor Cell ◽  
Serum Starvation ◽  
Oocyte Activation ◽  
Blastocyst Formation ◽  
Donor Cells ◽  
G0 Phase ◽  
G1 Cells

The cell cycle of donor cells and recipient cytoplasts are important factors affecting development of nuclear transferred (NT) embryos. We previously showed that bovine NT embryos using pre-activated cytoplasts and early G1 cells had a high in vitro developmental rate (SSR, 2008, 41st Annual Meeting). The objective of the present study was to evaluate the effects of donor cell cycle (early G1 or G0 phase) and the timing of oocyte activation on fetal development of bovine NT embryos. Adult fibroblasts from ear skin tissue of Japanese black cattle were used as donor cells. The G0 phase cells were synchronized by serum-starvation, and the G1 phase cells were prepared from actively dividing M phase cells. NT embryo production was performed by 2 kinds of protocols as follows: 1) recipient oocytes were activated by Ca ionophore (CaI), followed with cycloheximide (CH) for 2 h, and fused with synchronized donor cells followed with cytochalasin D (CD) and CH for 1 h, then CH for 4 h (pre-activated), 2) unactivated oocytes were fused with synchronized donor cells and activation was performed by CaI 1 h after fusion, followed by with CD and CH 1 h, then CH for 4 h (post-activated). After activation treatments, NT embryos were cultured in IVD101 medium for 7 days. Then, blastocysts were transferred to recipient cows. Diagnosis of pregnancy was made by ultrasonography at days 30, 60, and 90 (Day 0 = the day of embryo transfer). As shown in Table 1, the blastocyst formation rate of the NT embryos derived from early G1 cells in the pre-activated group was higher than that from G0 cells in the post-activated group (36% v. 23%, P < 0.05). After embryo transfer, 29, 67, and 50% of recipient cows were pregnant at Day 30 in G0 post-, G1 post-, and G1 pre-activated groups, respectively. However, only 1 embryo (14%) of G0 post-activated group developed to term. In conclusion, bovine NT embryos using early G1 cells and pre-activated cytoplasts showed a high blastocyst formation rate, but the full-term development of bovine NT embryos could not be improved by using early G1 cells and pre-activated cytoplasts. Table 1.Effect of the timing of oocyte activation on developmental ability of bovine NT embryos derived from early G1 or G0 phase cells

Effect of donor cell age on development of ovine nuclear transfer embryos in vitro

Zygote ◽  
2010 ◽  
Vol 18 (4) ◽  
pp. 331-338 ◽  
Author(s):  
B. Heidari ◽  
A. Shirazi ◽  
P. Tajic ◽  
E. Ahmadi ◽  
H. Nazari ◽  
...  
Keyword(s):  
Nuclear Transfer ◽  
Formation Rate ◽  
Donor Cell ◽  
Fibroblast Cell ◽  
Cumulus Cells ◽  
Blastocyst Formation ◽  
Donor Animal ◽  
Cell Age ◽  
Fetal Fibroblasts

SummaryThe effects of the age of cell donor animal on in vitro development of ovine nuclear transfer (NT) embryos were investigated. Somatic donor cells were obtained from two different sources: (1) adult cells (adult fibroblast cells; AFC and adult cumulus cells; ACC); and (2) fetal fibroblasts (40-day-old; FFC-40 and 65-day-old; FFC-65). The fibroblast cell lines were used for NT procedures within 4–13 subpassages. While the cumulus cells were used as non-cultured (fresh) cells. The in vitro matured abattoir-derived oocytes were considered as recipients. No differences in the rates of fusion (75.7, 77.7, 76.3 and 86.7%) and cleavage (80.1, 84.3, 77.8 and 74%) were detected among couplets reconstructed with FFC-40, FFC-65, AFC and ACC, respectively. Blastocyst formation rate of those oocytes reconstructed with FFC-40 was higher (18%; p < 0.001) than those reconstructed with FFC-65 (13%) and AFC (10.9) and comparable with those reconstructed with ACC (17.5%). When the effect of passage number was analysed within groups (FFC-40, FFC-65 and AFC) there were no significant differences in fusion, cleavage and blastocyst rates between reconstructed oocytes. The present study demonstrates that the fetal and adult fibroblasts as well as fresh cumulus cells are comparable in their ability to attain cell fusion and embryonic cleavage. Moreover, the blastocyst formation rate is influenced by the age of the donor animal and the fresh cumulus cells have similar remodelling potential to that of fetal fibroblasts in term of blastocyst formation rate.

scholarly journals BattleNet: Capturing Advantageous Battlefield in RTS Games (Student Abstract)

2020 ◽  
Vol 34 (10) ◽  
pp. 13849-13850
Author(s):  
Donghyeon Lee ◽  
Man-Je Kim ◽  
Chang Wook Ahn
Keyword(s):  
Artificial Intelligence ◽  
Decision Making ◽  
Real Time ◽  
Large Scale ◽  
Outcome Predictor ◽  
Short Term ◽  
Rts Game

In a real-time strategy (RTS) game, StarCraft II, players need to know the consequences before making a decision in combat. We propose a combat outcome predictor which utilizes terrain information as well as squad information. For training the model, we generated a StarCraft II combat dataset by simulating diverse and large-scale combat situations. The overall accuracy of our model was 89.7%. Our predictor can be integrated into the artificial intelligence agent for RTS games as a short-term decision-making module.

How to increase customer repeated bookings in the short-term room rental market? A large-scale granular data investigation

2021 ◽  
Vol 143 ◽  
pp. 113495
Author(s):  
Jiang Wu ◽  
Jingxuan Cai ◽  
Xin (Robert) Luo ◽  
Jose Benitez
Keyword(s):  
Large Scale ◽  
Short Term ◽  
Rental Market ◽  
Data Investigation

scholarly journals The Role of Risk Preferences in Responses to Messaging About COVID-19 Vaccine Take-Up

2021 ◽  
pp. 194855062199962
Author(s):  
Jennifer S. Trueblood ◽  
Abigail B. Sussman ◽  
Daniel O’Leary
Keyword(s):  
Large Scale ◽  
Risk Preferences ◽  
Herd Immunity ◽  
Disease Spread ◽  
Short Term ◽  
Policy Makers ◽  
Health Crisis ◽  
Flu Vaccine ◽  
Nationally Representative

Development of an effective COVID-19 vaccine is widely considered as one of the best paths to ending the current health crisis. While the ability to distribute a vaccine in the short-term remains uncertain, the availability of a vaccine alone will not be sufficient to stop disease spread. Instead, policy makers will need to overcome the additional hurdle of rapid widespread adoption. In a large-scale nationally representative survey ( N = 34,200), the current work identifies monetary risk preferences as a correlate of take-up of an anticipated COVID-19 vaccine. A complementary experiment ( N = 1,003) leverages this insight to create effective messaging encouraging vaccine take-up. Individual differences in risk preferences moderate responses to messaging that provides benchmarks for vaccine efficacy (by comparing it to the flu vaccine), while messaging that describes pro-social benefits of vaccination (specifically herd immunity) speeds vaccine take-up irrespective of risk preferences. Findings suggest that policy makers should consider risk preferences when targeting vaccine-related communications.

Overburdened Gauls: the case of Florus and Sacrovir’s revolt of 21 CE

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Jared Kreiner
Keyword(s):  
Interest Rates ◽  
Large Scale ◽  
Cumulative Effect ◽  
Short Term ◽  
Local Economies ◽  
Scale Resistance ◽  
Military Campaigns ◽  
The Impact

Abstract In 21 CE, a series of localized movements broke out in Gallia Comata due to heavy debts among provincials according to Tacitus. Modern scholars have long argued that the indebtedness occurred because of rising interest rates, resulting from dwindling currency in circulation after decades of free-spending following Augustus’ victory at Actium, and that Gallic communities were subjected to an additional tribute to support the wars of Germanicus (14–16 CE), which continued unabated after the wars and pushed Gauls beyond their means. These claims are misguided, however, in that there is no certain evidence of a special tax to support Germanicus’ wars and that the argument for a dwindling circulation of currency in Gaul falters under closer inspection. Rather, the pressing statal and military needs imposed on communities in Gallia Comata after 9 CE on top of routine exactions could significantly increase burden levels levied on provincial populations, thus contributing to rising debts. Through examining how Roman logistics and conscription operated in this period, it is possible to trace how populations were impacted by such demands and which communities were most heavily affected by them, too. Individually, the impact of each factor is unlikely to have been burdensome enough to have caused large-scale resistance, it is only the cumulative effect that these explanations had on top of routine Roman extraction schemes that could create the conditions for this revolt. This paper argues that in extraordinary circumstances, such as the period after the Varian Disaster for Gallia Comata, the costs of supporting military campaigns places real short-term strains on local economies, which creates the conditions for revolt. The benefit of this approach is that it may explain other episodes of anti-fiscal resistance that broke out during or within a decade of wars in neighboring regions.

scholarly journals Two Stage Continuous Gesture Recognition Based on Deep Learning

Electronics ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 534
Author(s):  
Huogen Wang
Keyword(s):  
Gesture Recognition ◽  
Large Scale ◽  
Short Term Memory ◽  
Short Term ◽  
Hand Motion ◽  
Spatiotemporal Features ◽  
Spatiotemporal Information ◽  
Video Frames ◽  
Depth Sequences

The paper proposes an effective continuous gesture recognition method, which includes two modules: segmentation and recognition. In the segmentation module, the video frames are divided into gesture frames and transitional frames by using the information of hand motion and appearance, and continuous gesture sequences are segmented into isolated sequences. In the recognition module, our method exploits the spatiotemporal information embedded in RGB and depth sequences. For the RGB modality, our method adopts Convolutional Long Short-Term Memory Networks to learn long-term spatiotemporal features from short-term spatiotemporal features obtained from a 3D convolutional neural network. For the depth modality, our method converts a sequence into Dynamic Images and Motion Dynamic Images through weighted rank pooling and feed them into Convolutional Neural Networks, respectively. Our method has been evaluated on both ChaLearn LAP Large-scale Continuous Gesture Dataset and Montalbano Gesture Dataset and achieved state-of-the-art performance.

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