Asynchrony between the early embryo and the reproductive tract affects subsequent embryo development in cattle

2020 ◽  
Vol 32 (6) ◽  
pp. 564 ◽  
Author(s):  
Beatriz Rodríguez-Alonso ◽  
José María Sánchez ◽  
Meriem Hamdi ◽  
Michael McDonald ◽  
Vitezslav Havlicek ◽  
...  

The aim of this study was to determine the effect of maternal–embryonic asynchrony in the reproductive tract (oviduct and uterus) on subsequent embryo development in cattle. Fifty Day 1invitro-produced zygotes were transferred endoscopically into the oviduct ipsilateral to the corpus luteum of heifers (n=40) that were either synchronous with the embryos (Day 1 after ovulation) or asynchronous and ahead of the embryo (Day 3 after ovulation). A subset of heifers was killed in a commercial abattoir 3, 6 or 14 days after embryo transfer. Location within the reproductive tract, developmental stage and the quality of embryos were recorded. Transfer of embryos to an advanced (asynchronous) oviduct resulted, on Day 4, in fewer embryos at the expected location (oviduct), and a greater number of degenerated and retarded embryos with a lower total cell number than for embryos in the synchronous group. Similarly, on Day 7, asynchrony led to a greater number of degenerated and retarded embryos compared with the synchronous group. Total embryo cell number was similar among groups. Although Day 15 conceptuses were longer following asynchronous transfer, only 50% of the asynchronous heifers yielded conceptuses, compared with 100% in the synchronous group. In conclusion, asynchrony between the developing embryo and the reproductive tract has a negative effect on embryo development.

Zygote ◽  
2021 ◽  
pp. 1-6
Author(s):  
Haixia Wang ◽  
Wenbin Cao ◽  
Huizhong Hu ◽  
Chenglong Zhou ◽  
Ziyi Wang ◽  
...  

Summary Many studies have focused on the optimization of the composition of embryo culture medium; however, there are few studies involving the effect of a culture medium changing procedure on the preimplantation development of embryos. In this study, three groups were designed: a non-renewal group, a renewal group and a half-renewal group. The levels of reactive oxygen species (ROS), apoptotic index, blastocyst ratio and blastocyst total cell number were analyzed in each group. The results showed that the ROS level and the apoptotic index of blastocyst in the non-renewal group were significantly higher than in the renewal group and the half-renewal group (P < 0.05). The blastocyst ratio and blastocyst total cell number were significantly higher in the half-renewal group than that in non-renewal group and the renewal group (P < 0.05). These results demonstrated that the procedure of changing the culture medium influenced ROS level, apoptotic index, blastocyst ratio and total cell number of blastocysts. In addition, the result suggested that changing the culture medium may lead to a loss of important regulatory factors for embryos, while not changing the culture medium may lead to the accumulation of toxic substances. Half-renewal can alleviate the defects of both no renewal and renewal, and benefit embryo development. This study will be of high value as a reference for the optimization of embryo culture in vitro, and is very significant for assisted reproduction.


2014 ◽  
Vol 26 (4) ◽  
pp. 570 ◽  
Author(s):  
Eva Torner ◽  
Eva Bussalleu ◽  
M. Dolors Briz ◽  
Marc Yeste ◽  
Sergi Bonet

In the present study, the effects of replacing glucose with pyruvate–lactate and supplementing these in vitro culture (IVC) media with hyaluronic acid (HA) on porcine embryo development and sex ratio were examined. The in vitro-produced (IVP) porcine embryos were cultured in NCSU-23 medium with 0.0, 0.5 or 1.0 mg mL–1 HA, and with either 5.55 mM glucose (IVC-Glu) or pyruvate (0.17 mM)–lactate (2.73 mM) from 0 to 48 h post insemination (h.p.i.) and then with glucose from 48 to 168 h.p.i. (IVC-PL). Those embryos cultured with IVC-PL had significantly higher blastocyst rates (23.7 ± 1.5%) than those cultured with IVC-Glu (14.27 ± 2.75%). At 1.0 mg mL–1, HA tended to skew the sex ratio of blastocysts towards males in those embryos cultured in IVC-PL, and led to a significant decrease in the blastocyst rate compared with embryos cultured in the presence of 0.5 and 0.0 mg mL–1 HA and IVC-Glu (4.28 ± 0.28% vs 11.01 ± 1.42% and 10.14 ± 2.77%, respectively) and IVC-PL (14.37 ± 1.35% vs 20.96 ± 2.85% and 22.99 ± 1.39%, respectively). In contrast, there were no significant differences in the total cell number per blastocyst or in apoptosis rates. In conclusion, pyruvate and lactate were the preferred energy substrates in the early stages of IVP porcine embryos. Moreover, 1.0 mg mL–1 HA significantly decreased the percentage of blastocyst rates in both the IVC-Glu and IVC-PL groups, but only by a preferential loss of female embryos for those cultured in IVC-PL.


2006 ◽  
Vol 18 (2) ◽  
pp. 185 ◽  
Author(s):  
Y. Agca ◽  
H. Men ◽  
S. F. Mullen ◽  
L. K. Riley ◽  
R. S. Prather ◽  
...  

The ability to produce porcine embryos of good quality will have a significant impact on a number of porcine assisted reproductive technologies, such as cloning, intracytoplasmic sperm injection, and embryo cryopreservation. However, porcine embryos resulting from current serum-free embryo culture systems differ significantly both structurally and functionally from those derived in vivo (Wang et al. 1999 Mol. Reprod. Dev. 53, 99-107). In this experiment, the quality of porcine embryos produced by North Carolina State University (NCSU)-23 medium (Petters and Wells 1993 J. Reprod. Fertil. Suppl. 1993, 48, 61-73) and porcine zygote medium (PZM)-1 (Yoshioka et al. 2002 Biol. Reprod. 66, 112-119) were compared by assessing the total cell number and the time course of in vitro blastocyst hatching. Porcine embryos were produced by in vitro maturation and fertilization using serum-free systems. After fertilization, presumptive zygotes were randomly allocated to either PZM-1 or NCSU-23 for subsequent development. On Day 4 of culture, the embryo culture media were supplemented with 10% fetal bovine serum (FBS). Day 6 blastocysts from each group were counted and the blastocysts were subsequently fixed in 4% formalin for counting the total cell number. The cell number in each embryo was determined by counting the nuclei after staining with bisbenzimide (Hoechst 33342). To assess the hatching ability of blastocysts, Day 6 blastocysts were cultured until Day 9 and hatched blastocysts were counted daily. Day 6 blastocyst rates (ratio of blastocysts to oocytes) and total cell number count were replicated three times. The time course of blastocyst hatching experiment was repeated four times. The data were analyzed using a chi-square test, Fisher's exact test, or Student's t-test. The blastocyst rate from culture in PZM-3 was 19.4 � 0.96% (mean � SEM), which was similar to that (16.7 � 3.2%) resulting from culture in NCSU-23 (P > 0.05). However, the total cell number in Day 6 blastocysts cultured in PZM-3 was significantly higher than for blastocysts cultured in NCSU-23 (57 � 3.1 vs. 46 � 1.7; P < 0.01). The total hatching rates (ratio of hatched blastocysts to total blastocysts) by Day 9 were similar between the two culture systems (50.1 � 9.1% vs. 50.7 � 4.1%; P > 0.05). However, on Day 6, 2.1% of blastocysts from PZM-3 culture hatched whereas no blastocysts from NCSU-23 culture hatched. The cumulative hatching rates from PZM-3 culture on Day 7 were significantly higher than those from NCSU-23 culture (15.1 � 3.8% vs. 2.6 � 1.1%; P < 0.01). In conclusion, these data suggest that blastocysts produced in PZM-3 medium have better quality than blastocysts produced in the NCSU-23 culture system as assessed by the total cell number and the time course of blastocyst hatching. This project was supported by a grant from the National Institutes of Health (U42 RR 018877).


Reproduction ◽  
2015 ◽  
Vol 149 (4) ◽  
pp. 347-355 ◽  
Author(s):  
Ikuko Yashiro ◽  
Miho Tagiri ◽  
Hayato Ogawa ◽  
Kazuya Tashima ◽  
Seiji Takashima ◽  
...  

The objective of this study was to investigate whether developmental competence of vitrified–warmed bovine oocytes can be improved by antioxidant treatment during recovery culture. In experiment 1, one of the two antioxidants (either l-ascorbic acid or α-tocopherol) was added as a supplement to the recovery culture medium to which postwarming oocytes were exposed for 2 h before IVF. The exposure to α-tocopherol had a positive effect on rescuing the oocytes as assessed by the blastocyst yield 8 days after the IVF (35.1–36.3% vs 19.2–25.8% in untreated postwarming oocytes). Quality of expanding blastocysts harvested on Day 8 was comparable between α-tocopherol-treated vitrification group and fresh control group in terms of total cell number and chromosomal ploidy. In experiment 2, level of reactive oxygen species, mitochondrial activity, and distribution of cortical granules in α-tocopherol-treated postwarming oocytes were assessed. No obvious differences from the control data were found in these parameters. However, the treatment with α-tocopherol increased the percentage of zygotes exhibiting normal single aster formation (90.3% vs 48.0% in untreated postwarming oocytes; 10 h post-IVF). It was concluded that α-tocopherol treatment of vitrified–warmed bovine mature oocytes during recovery culture can improve their revivability, as shown by the high blastocyst yield and the higher mean total cell number in the blastocysts.


2019 ◽  
Vol 129 ◽  
pp. 70-76 ◽  
Author(s):  
Junchul David Yoon ◽  
Seon-Ung Hwang ◽  
Mirae Kim ◽  
Gabsang Lee ◽  
Yubyeol Jeon ◽  
...  

2005 ◽  
Vol 17 (2) ◽  
pp. 221
Author(s):  
J.H. Kim ◽  
G.S. Lee ◽  
H.S. Kim ◽  
S.H. Lee ◽  
D.H. Nam ◽  
...  

Developing a porcine embryo culture system is important for increasing the rates of implantation and pregnancy of somatic cell nuclear transfer (SCNT) embryos. Ethylenediaminetetraacetic acid (EDTA) was shown to inhibit glycolytic activity of cleavage stage embryos, thereby preventing the premature stimulation of glycolysis and enhancing development. However, EDTA should not be used for later-stage embryos as the inhibition of glycolysis reduces energy production at the blastocyst stage and significantly inhibits inner cell mass development. On the other hand, addition of a nitric oxide (NO) scavenger, hemoglobin (Hb), to the culture medium is known to promote embryo development to the blastocyst stage. This study was conducted to evaluate the beneficial effect of EDTA combined with Hb on pre-implantation development of porcine embryos in vitro. Porcine embryos produced by in vitro maturation and fertilization were cultured for 6 days in North Carolina State University (NCSU)-23 medium supplemented with EDTA or/and Hb. All data were subjected to one-way ANOVA and protected least significant difference (LSD) test using the general linear models (GLM) procedure of the statistical analysis system (SAS Institute, Inc., Cary, NC, USA) program to determine differences among experimental groups. Statistical significance was determined when the P value was less than 0.05. In Exp. 1, culturing porcine zygotes with 100 mM EDTA (n = 537) significantly increased cleavage rates (85.3%) at 48 h post-insemination compared to supplementing with 0, 1, or 10 mM EDTA (78.9, 79.7, or 78.2%, respectively). However, EDTA at these concentrations did not promote blastocyst formation compared to the control. In addition, no difference was observed in total cell numbers in blastocysts among the experimental groups (41.8, 42.6, 45.8, 44.5, respectively). In Exp. 2, in vitro-fertilized oocytes were cultured with 0, 1, or 10 mg/mL Hb. Culturing with Hb did not promote porcine embryo development, but significantly increased the total cell number of blastocysts obtained from 1 mg/mL Hb supplementation (n = 566) compared to that of the control (56.8 vs. 41.6). In Exp. 3, culturing embryos (n = 548) with 100 mM EDTA + 1 mg/mL Hb significantly improved rates of cleavage (84.0% vs. 75.2%) and blastocyst formation (19.2% vs. 12.7%), and the total number of cells in blastocysts compared to those of the control (58.4 vs. 42.3). In conclusion, our results demonstrated that EDTA or Hb have different roles in supporting in vitro pre-implantation development of porcine embryos; EDTA mainly stimulated early cleavage up to the 2- to 4-cell stage, and Hb promoted the total cell number of blastocysts. However, combined supplementation with these two chemicals improved cleavage, blastocyst formation, and total cell number in blastocysts. This study was supported by a grant from Korea Ministry of Science and Technology (Biodiscovery).


2007 ◽  
Vol 19 (1) ◽  
pp. 213
Author(s):  
M. Takahashi ◽  
K. Nagayama ◽  
M. Sakatani ◽  
S. Kobayashi ◽  
K. Morishita ◽  
...  

We investigated the antioxidative effect of brown algae phlorotannins on reactive oxygen species (ROS) generation and embryo development of parthenogenetically activated porcine embryos under oxidative and heat-stressed conditions. Cumulus–oocyte complexes (COCs) were aspirated from follicles on the surface of porcine ovaries collected from an abbattoir. COCs were matured in NCSU-23 containing 10% (v/v) porcine follicular fluid and hCG during the first 22 h, followed by an extra 22 h of culture in hormone-free NCSU-23. After 44 h of maturation, oocytes were denuded of cumulus cells and used for parthenogenetic activation. Oocytes were activated by single 100-�s pulse of 1.5 kV cm-1 DC in 1-mm electrodes. Activated oocytes were cultured for 5 h in NCSU-23 containing BSA, EGF, and 5 �g mL-1 cytochalasin B. Embryos were then cultured for 7 days in PZM-5 medium that was a slightly modified version of the PZM-4 medium reported by Yoshioka et al. (2002 Biol. Reprod. 60, 112–119). In Experiment 1, after parthenogenetic activation, embryos were cultured for 7 days at 38.5�C under 5% O2, 5% CO 2, and 90% N2 (defined as 5% O2) as a control. Embryos were also cultured under 5% CO2 in air (defined as 20% O2) with or without 100 ng mL-1 brown algae phlorotannins extracted from Ecklonia kurome. The number of embryos developed to the blastocyst stage was observed on Day 6. The total cell number of Day 7 blastocysts was counted by DAPI staining of nuclei. On Day 2, intracellular ROS levels of individual embryos were measured with fluorescent dyes (222,722-dichlorodihydrofluorescein diacetate). In Experiment 2, on Day 1 or 2, embryos cultured in 5% O2 concentration at 38.5�C were exposed to 41.5�C for 6 h with or without 100 ng mL-1 phlorotannins and cultured at 38.5�C until Day 7. After 6 h of heat-shock on Day 1 or Day 2, intracellular ROS levels were measured as described in Experiment 1. Statistical analysis was carried out by ANOVA. In Experiment 1, the rate of blastocyst formation and the total cell number were significantly decreased (P &lt; 0.05) when embryos were cultured under 20% O2 compared to 5% O2. In contrast, addition of phlorotannins significantly increased the rate of blastocyst formation under high O2 concentration. ROS levels were also significantly increased by higher O2 concentration. In contrast, addition of phlorotannins significantly reduced the ROS levels. In Experiment 2, heat-shock to embryos on Days 1 and 2 significantly (P &lt; 0.05) decreased the rate of blastocyst formation compared to the control. In contrast, addition of phlorotannins significantly (P &lt; 0.05) increased embryo development and decreased the intracellular ROS levels of heat-stressed embryos. These results indicate that oxidative and heat stress conditions decrease embryo development and increase the level of intracellular ROS. However, addition of phlorotannins promotes embryo development by decreasing the oxidative stress.


2007 ◽  
Vol 19 (1) ◽  
pp. 210
Author(s):  
D. W. Linck ◽  
D. K. Gardner

Recently, there has been much debate involving the time necessary to effectively equilibrate an embryo culture system, i.e. dishes, media, and oil. Glutamine present in the culture medium spontaneously deaminates at 37�C to release embryo-toxic ammonium. Additionally, the source of the oil overlay can impact the culture environment. A sub-optimal oil overlay, combined with free glutamine (Gln), could effectively become embryo-toxic over a short time period (&lt;48 h). Therefore, the aim of this study was to determine how times of media equilibration, using various combinations of oil source and type of Gln, affect embryo development. Zygotes were collected from 4-week-old CF1 outbred female mice following superovulation and mating. Embryos were cultured in groups of 10 in 20-�L drops of medium G1.2. Initially, embryos were cultured in one of 4 treatment media. In this 2 � 2 factorial design, the culture medium was pre-equilibrated 18 h prior to embryo retrieval and contained free Gln or the heat-stable dipeptide alanyl-glutamine (AlaGln), combined with an oil source of either Sigma mineral oil (Sigma-Aldrich Corp., St Louis, MO, USA) or Ovoil paraffin oil (Vitrolife, Inc., Englewood, CO, USA). The initial study was then repeated using only the best and worst case groups to determine the effect of incubation time as a variable (either 2 h or 18 h). Blastocyst development and total cell numbers were analyzed after 72 h of culture, and differences between treatments were assessed using Fisher&apos;s exact test and Student&apos;s t-test. After 18 h of pre-equilibration (n e 300 embryos/treatment), blastocyst development in Ovoil + AlaGln (38.6%) was significantly greater when compared to: Ovoil + Gln: 25.5% (P &lt; 0.01), Sigma + AlaGln: 12.8% (P &lt; 0.01), and Sigma + Gln: 11.9% (P &lt; 0.01). Additionally, the total cell numbers in comparison to Ovoil + AlaGln (44.6 � 10) were significantly decreased: 35.5 � 7 (P &lt; 0.001), 34.9 � 9 (P &lt; 0.001), and 29.9 � 9 (P &lt; 0.001), respectively. In the second experiment, blastocyst development and total cell number between Ovoil + AlaGln (n = 224) and Sigma + Gln (n = 264) after 18 h of pre-equilibration were: 40.4% vs. 9.9% (P &lt; 0.01) and 46.6 � 9 vs. 29.4 � 9 P &lt; 0.001), respectively. However, after 2 h of pre-equilibration, the results between Ovoil + AlaGln (n = 260) and Sigma + Gln (n = 284) were: 42.3% vs. 18.3% (P &lt; 0.01) and 46.9 � 10 vs. 33.6 � 6 (P &lt; 0.001), respectively. Therefore, when comparing blastocyst development and total cell number between pre-equilibration times (2 h vs. 18 h), the Ovoil + AlaGln group, 42.3% vs. 40.4% and 46.9 � 10 vs. 46.6 � 9, showed no significant differences, respectively. In contrast, the Sigma + Gln group produced significant differences for both blastocyst development, 18.3% vs. 9.9% (P &lt; 0.01), and total cell number, 33.6 � 6 vs. 29.4 � 9 (P &lt; 0.05), between pre-equilibration times (2 h vs. 18 h), respectively. Data presented confirm the need for an alternative source of glutamine in embryo culture media. The data also indicate that the source of oil has a profound effect on the experimental outcome. Using the appropriate oil and form of Gln means that media can be safely equilibrated for 18 h.


2018 ◽  
Vol 30 (1) ◽  
pp. 222
Author(s):  
S. H. Lee ◽  
E. M. N. Setyawan ◽  
B. C. Lee

Progesterone (P4) and progesterone receptor signalling appears essential for maintenance of a proper cumulus cell expansion during the oocyte maturation by regulating the epidermal growth factor-like factors (EGF-F) related pathway during the ovulatory process. It is known that expression of EGF-F including amphiregulin (AREG), epiregulin (EREG), and betacellulin (BTC) is critical for cumulus–oocyte complex (COC) expansion and resumption of meiosis. Therefore, we hypothesised that oviduct cells might be involved in nonexclusive mechanisms of actions of P4 that in turn modulate oocyte meiosis resumption by regulating the levels of EGF-F. First, we added different concentrations of P4 (0, 0.5, 1, and 2 μg mL−1) to oviduct cell culture medium and assessed the effect of P4 on expression of AREG, EREG, and BTC in oviduct cells by immunocytochemical analysis. Then, the oviduct cells were used for co-culturing under the proper concentration of P4 with porcine oocytes. The COC were randomly cultured in 3 groups: (1) culturing without oviduct cells, (2) co-culturing with oviduct cells, and (3) co-culturing with oviduct cells treated with P4. After IVM, extrusion of the 1st polar body was observed under the microscope. To evaluate embryo development competence, the matured oocytes were activated with electrical stimulus and parthenotes were cultured in porcine zygote medium-5 for 7 days at 39°C, 5% CO2 and O2 in a humidified atmosphere. The cleavage and blastocyst formation rates were observed under the microscope to evaluate developmental competence. To count the total cell number of blastocysts, they were stained with 5 μg mL−1 of Hoechst 33342 for 10 min. The data were analysed by one-way ANOVA using GraphPad Prism 5.0 (GraphPad Inc., San Diego, CA, USA). Values are means ± standard error of mean (P < 0.05). Significantly higher levels of EGF-F were observed in oviduct cells treated with 1 μg mL−1 progesterone. The oocyte maturation rate of co-culture group treated with P4 (80.7 ± 1.6%) was significantly higher than that of the control (69.7 ± 2.1%). There was a significant difference between co-culture treated with P4 and the control in cleavage rate (67.2 ± 2.4% and 82.0 ± 1.6%). However, no significant difference was observed between the co-culture groups. The co-culture treated with P4 group showed significantly higher rate of blastocyst formation (37.7 ± 0.8%) and total cell number of blastocyst (72.8 ± 1.0) than control and co-culture groups. In conclusion, co-culturing with oviduct cell treated with P4 improved oocyte maturation and subsequent embryo development. Thus, we suggested that oviduct cells induce the expression of EGF-F under the treatment of P4, which has a beneficial effect on porcine oocyte development. This research was supported by NRF-20142A1021187, Korea IPET (#316002-05-2-SB010), RDA (#PJ010928032017) and Research Institute for Veterinary Science, the BK21 plus program.


2016 ◽  
Vol 28 (2) ◽  
pp. 237
Author(s):  
R. Poole ◽  
V. McCracken ◽  
M. Rhoads ◽  
K. Lee

Infertility among women has become a growing issue in the world requiring a significant number to seek treatment by means of assisted reproductive technologies. One suggested reason for the fertility issue, which is known to specifically affect oocyte quality, is the modern diet. Previously, we have demonstrated that feeding a high-fructose diet to gilts led to poor reproductive tract characteristics and infertility. In this study, pre-pubescent gilts were fed either a high-fructose; high-fat diet (HFHF), with 15% beef tallow and 35% fructose; or an industry control diet (IND). Porcine follicular fluid (pFF) collected from these gilts was introduced into in vitro maturation systems to determine whether characteristics of the follicular fluid affect oocyte competence and embryo development. Follicles from ovaries, collected at a local abattoir, were aspirated by an 18 G needle attached to a 10-mL sterile syringe. Then selected cumulus‐oocyte complexes were maturated in vitro in a TCM-199 maturation media with cysteine, glucose, sodium pyruvate, epidermal growth factor (EGF), FSH, LH, and 20% pFF from treatment groups. Additionally, another group of oocytes, labelled follicle fluid free (FFF), were maturated in TCM-199 media without pFF. Three replicate experiments were conducted using a total of 365 oocytes, 124 FFF, 121 IND, and 120 HFHF. Oocytes were denuded by exposure to 0.1% hyaluronidase and oocytes that reached metaphase II (MII) were selected for in vitro fertilisation. After 5 h of co-incubation in modified Tween medium B with milk powder (mTBM)-based IVF media, presumable zygotes were transferred to porcine zygote medium-3 (PZM-3). Blastocyst frequency was recorded on Days 5 and 6. Day 6 blastocysts were stained with Hoechst for total cell number evaluation. The frequencies of blastocyst formation among the treatment groups were compared by a chi-squared test, and total cell numbers were compared by Student's t-test. Statistical significance was defined by P < 0.05. The frequency of oocytes reaching metaphase II (MII) were observed as 77.4% FFF, 72.7% IND, and 71.7% HFHF (P > 0.05), indicating the supplementation of pFF did not affect maturation. Day 5 blastocysts were observed at frequencies of 8.3% FFF, 6.8% IND, and 4.7% HFHF and did not differ. However, frequency of Day 6 blastocysts from HFHF group was tended to be lower compared with that of other groups; 12.5% FFF, 11.4% IND, and 4.7% HFHF (P = 0.06 and P = 0.1). Average total cell number of Day 6 blastocysts observed were 41.0 ± 9.1 FFF, 36.0 ± 8.9 IND, and 48.3 ± 10.6 HFHF. The total cell number from HFHF group tended to be higher than only that of IND group (P = 0.07). Based on these results, we concluded that the follicular fluid of females consuming HFHF diets did not have impact on nuclear maturation of oocytes but might affect oocyte competency, thus resulting in detrimental effects on subsequent development of embryos, especially blastocyst formation. Further studies will help us identify more specific effects of nutrition on oogenesis and subsequent embryo development.


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