This work was supported by funds from the Department of Animal and Avian Sciences to BT.

All animal experiments were approved by the Beltsville Area Animal Care and Use Comittees (BAACUC 11-015) in accordance with USDA Animal Care and Use Guidelines.
1. Anesthesia and Analgesia (Common for Both Surgical Procedures)
<ol>
	<li>Weigh the mouse and load the following anesthetics and analgesic in two 1 ml syringes with 27 G needles:
	<ol>
		<li>Ketamine (0.1 mg/g: 0.01 ml/g of a 10 mg/ml solution) and xylazine (0.01 mg/g: 0.005 ml/g of a 2 mg/ml solu...

<ol>
	<li>Fernandez-Gonzalez, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Long-term+effect+of+in+vitro+culture+of+mouse+embryos+with+serum+on+mRNA+expression+of+imprinting+genes,+development,+and+behavior.">Long-term effect of in vitro culture of mouse embryos with serum on mRNA expression of imprinting genes, development, and behavior.</a> Proc. Natl. Acad. Sci USA. 101, 5880-5885 (2004).</li><li>Bermejo-Alvarez, P., Roberts, R. M., Rosenfeld, C. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+glucose+concentration+during+in+vitro+culture+of+mouse+embryos+on+development+to+blastocyst,+success+of+embryo+transfer,+and+litter+sex+ratio.">Effect of glucose concentration during in vitro culture of mouse embryos on development to blastocyst, success of embryo transfer, and litter sex ratio.</a> 79, 329-336 (2012).</li><li>Tarkowski, A. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Experiments+on+the+development+of+isolated+blastomers+of+mouse+eggs.">Experiments on the development of isolated blastomers of mouse eggs.</a> Nature. 184, 1286-1287 (1959).</li><li>Whittingham, D. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fertilization+of+mouse+eggs+in+vitro.">Fertilization of mouse eggs in vitro.</a> Nature. 220, 592-593 (1968).</li><li>McLaren, A., Biggers, J. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Successful+development+and+birth+of+mice+cultivated+in+vitro+as+early+as+early+embryos.">Successful development and birth of mice cultivated in vitro as early as early embryos.</a> Nature. 182, 877-878 (1958).</li><li>McLaren, A., Michie, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Studies+on+the+transfer+of+fertilized+mouse+eggs+to+uterine+foster-mothers.+I.+Factors+affecting+the+implantation+and+survival+of+native+and+transferred+eggs.">Studies on the transfer of fertilized mouse eggs to uterine foster-mothers. I. Factors affecting the implantation and survival of native and transferred eggs.</a> J. Exp. Biol. 33, 394-416 (1956).</li><li>Goto, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+fate+of+embryos+transferred+into+the+uterus.">The fate of embryos transferred into the uterus.</a> J. Assist. Reprod. Gen. 10, 197-201 (1993).</li><li>Nagy, A., Gertsenstein, M., Vintersten, K., Behringer, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Manipulating the Mouse Embryo: A Laboratory Manual. , (2003).</li><li>Chin, H. J., Wang, C. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Utero-tubal+transfer+of+mouse+embryos.">Utero-tubal transfer of mouse embryos.</a> Genesis. 30, 77-81 (2001).</li><li>Ramirez, M. A., Fernandez-Gonzalez, R., Perez-Crespo, M., Pericuesta, E., Gutierrez-Adan, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+stem+cell+activation,+culture+media+of+manipulated+embryos,+and+site+of+embryo+transfer+in+the+production+of+F0+embryonic+stem+cell+mice.">Effect of stem cell activation, culture media of manipulated embryos, and site of embryo transfer in the production of F0 embryonic stem cell mice.</a> Biol. Reprod. 80, 1216-1222 (2009).</li><li>Miller, A. M., Wright-Williams, S. L., Flecknell, P. A., Roughan, J. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+comparison+of+abdominal+and+scrotal+approach+methods+of+vasectomy+and+the+influence+of+analgesic+treatment+in+laboratory+mice.">A comparison of abdominal and scrotal approach methods of vasectomy and the influence of analgesic treatment in laboratory mice.</a> Lab. Anim. 46, 304-310 (2012).</li><li>Flecknell, P. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Laboratory Animal Anaesthesia. , (2009).</li><li>Erhardt, W., Hebestedt, A., Aschenbrenner, G., Pichotka, B., Blumel, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+comparative+study+with+various+anesthetics+in+mice+(pentobarbitone+ketamine-xylazine,carfentanyl-etomidate).">A comparative study with various anesthetics in mice (pentobarbitone ketamine-xylazine,carfentanyl-etomidate).</a> Res. Exp. Med. 184, 159-169 (1984).</li><li>Tarin, D., Sturdee, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Surgical+anaesthesia+of+mice:+evaluation+of+tribromo-ethanol,+ether,+halothane+and+methoxyflurane+and+development+of+a+reliable+technique.">Surgical anaesthesia of mice: evaluation of tribromo-ethanol, ether, halothane and methoxyflurane and development of a reliable technique.</a> Lab. Anim. 6, 79-84 (1972).</li><li>Zeller, W., Meier, G., Burki, K., Panoussis, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Adverse+effects+of+tribromoethanol+as+used+in+the+production+of+transgenic+mice.">Adverse effects of tribromoethanol as used in the production of transgenic mice.</a> Lab. Anim. 32, 407-413 (1998).</li><li>Lieggi, C. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Efficacy+and+safety+of+stored+and+newly+prepared+tribromoethanol+in+ICR+mice.">Efficacy and safety of stored and newly prepared tribromoethanol in ICR mice.</a> Contemp. Top. Lab. Anim. Sci. 44, 17-22 (2005).</li><li>Lieggi, C. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+evaluation+of+preparation+methods+and+storage+conditions+of+tribromoethanol.">An evaluation of preparation methods and storage conditions of tribromoethanol.</a> Contemp. Top. Lab. Anim. Sci. 44, 11-16 (2005).</li><li>Meyer, R. E., Fish, R. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+review+of+tribromoethanol+anesthesia+for+production+of+genetically+engineered+mice+and+rats.">A review of tribromoethanol anesthesia for production of genetically engineered mice and rats.</a> Lab. Anim. 34, 47-52 (2005).</li><li>Chatot, C. L., Lewis, J. L., Torres, I., Ziomek, C. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+1-cell+embryos+from+different+strains+of+mice+in+CZB+medium.">Development of 1-cell embryos from different strains of mice in CZB medium.</a> Biol. Reprod. 42, 432-440 (1990).</li><li>Quinn, P., Barros, C., Whittingham, D. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preservation+of+hamster+oocytes+to+assay+the+fertilizing+capacity+of+human+spermatozoa.">Preservation of hamster oocytes to assay the fertilizing capacity of human spermatozoa.</a> J. Reprod. Fertil. 66, 161-168 (1982).</li><li>Dios Hourcade, d. e., Perez-Crespo, J., Serrano, M., Gutierrez-Adan, A., A, B., Pintado, <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vitro+and+in+vivo+development+of+mice+morulae+after+storage+in+non-frozen+conditions.">In vitro and in vivo development of mice morulae after storage in non-frozen conditions.</a> Reprod. Biol. Endocrinol. 10, 62 (2012).</li></ol>

Vasectomy is a relatively straight forward surgical technique that does not involve major difficulties. When sanitizing with povidone iodine and ethanol make sure that the last wash (with ethanol) removes povidone iodine, as it may irritate the peritoneum. The access to vas deferens can also be achieved by the scrotum or performing a transversal incision in the abdomen8. Scrotal incision has been recommended to transversal abdominal incision due to the comparatively smaller incision needed and slightl...

Embryo transfer is probably the most frequent surgical procedure performed in the mouse model. This technique is essential to obtain offspring from embryos subjected to in vitro manipulation techniques and, therefore, constitutes a necessary step for the development of genetically modified models by pronuclear injection, lentiviral transduction, or chimera formation. Besides, the technique allows the study of the developmental effects of diverse insults occurring during preimplantation development. The use of artificial reproduction techniques1 or the exposure to abnormal concentrations of different substances or metabolites2 may affect embryo development resulting in implantation or placentation failures and long term effects in the offspring. A reliable and reproducible embryo transfer technique is crucial to test the possible negative effects of the experimental treatment on implantation and fetal development in a consistent manner.
Murine preimplantation embryos can be transferred to a recipient female either into the oviduct via the ampullae of 0.5 days post coitum (dpc) pseudopregnant recipients (oviduct transfer)3,4 or into the uterus of 2.5 dpc pseudopregnant recipient (uterine transfer)5,6 depending on their developmental stage. Embryos at the blastocyst stage, such as those used to generate chimeric mice by injection of embryonic or induced pluripotent stem cells, are usually transferred by uterine transfer. Blastocysts can also be transferred to the oviduct of a 0.5 dpc recipient, but it constitutes a less physiological test for developmental disruptors, because the embryo undergoes diapause and has 2 days to recover from the insult before implantation takes place. Uterine transfer involves puncturing the uterine wall with a narrow needle in order to generate an aperture that allows the access of an embryo manipulation pipette into the uterine lumen. Although this technique can yield good results, the survival to term (i.e. the percentage of embryos transferred that develop to a pup) is often low and unpredictable7,8.
The puncture of the uterine wall entails some detrimental side effects. First, myometrium is a highly vascularized tissue and its puncture often results in a small hemorrhage. Blood may block the embryo transfer pipette or invade the uterine lumen causing embryonic death and/or implantation failure. This is particularly relevant when embryos without zona are transferred, as the blood cells and debris can attach to the blastomeres. Second, the opening performed does not seal after the embryos have been transferred, so they can flow back through the orifice and be expelled to the abdominal cavity when a too large volume has been introduce into the uterus. The utero-tubal embryo transfer described herein take advantage of the utero-tubal junction to deliver the embryos into the uterus without the need of puncturing the uterine wall and thereby avoiding its adverse consequences9.
The pseudopregnant recipient females used for embryo transfer are obtained by natural mating with vasectomized males8. The seminal secretions produced by a sterile male are required for the uterus to become receptive to the transferred embryos. To obtain a recipient, a maximum of 2 females of 8 weeks to 6 months of age are placed with a vasectomized male in the afternoon. The following morning, females are checked for the presence of a vaginal copulation plug, a clump of coagulated proteins from the male seminal fluid. As mating usually occurs during midnight, the day of vaginal plug detection is considered to be 0.5 dpc. Although vasectomized males can be purchased from some vendors, the surgical procedure described herein is relatively easy and does not require any additional instruments than required for embryo transfer.

<table border="0" cellpadding="0" cellspacing="0" width="1234">
	<colgroup>
		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="29">
			<td height="29" style="height:29px;width:232px;">Ketamine</td>
			<td style="width:111px;">VEDCO</td>
			<td style="width:203px;">Ketaved ANADA 200-257</td>
			<td style="width:691px;">To be ordered by a licensed veterinarian.</td>
		</tr>
		<tr height="23">
			<td height="23" style="height:23px;width:232px;">Xylazine</td>
			<td style="width:111px;">Lloyd laboratories</td>
			<td style="width:203px;">Anased NADA #139-236</td>
			<td style="width:691px;">To be ordered by a licensed veterinarian.</td>
		</tr>
		<tr height="24">
			<td height="24" style="height:24px;width:232px;">Buprenorphine</td>
			<td style="width:111px;">Generic</td>
			<td style="width:203px;">NDC 400-42-010-01</td>
			<td style="width:691px;">To be ordered by a licensed veterinarian.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:232px;">Eye ointment</td>
			<td style="width:111px;">Novartis</td>
			<td style="width:203px;">Genteal</td>
			<td style="width:691px;"></td>
		</tr>
		<tr height="36">
			<td height="36" style="height:36px;width:232px;">Antibiotic</td>
			<td style="width:111px;">Pfizer</td>
			<td style="width:203px;">Clavamox NADA #55-101.</td>
			<td style="width:691px;">Added to drinking water (0.3 mg/ml of amoxicillin trihydrate and 0.075 mg/ml of clavulanate potassium). Add 1.5 ml of the reconstituted 15 ml bottle to 250 ml of water.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:232px;">Dressing serrated forceps</td>
			<td style="width:111px;">ROBOZ</td>
			<td style="width:203px;">RS-8120</td>
			<td style="width:691px;">Any medium size surgical-grade steel straight forceps will work.</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:232px;">Micro dissecting serrated forceps</td>
			<td style="width:111px;">ROBOZ</td>
			<td style="width:203px;">RS-5137</td>
			<td style="width:691px;">These ones are curved at a 90&#186; angle. Straight forceps can be used if preferred.</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:232px;">Slight curved micro dissection forceps</td>
			<td style="width:111px;">ROBOZ</td>
			<td style="width:203px;">RS-5136</td>
			<td style="width:691px;">This model is particularly useful to hold the oviduct.</td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:232px;">Scissors</td>
			<td style="width:111px;">ROBOZ</td>
			<td style="width:203px;">RS-5880</td>
			<td style="width:691px;">Any regular surgical grade steel small straight scissors will work.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:232px;">27G needles</td>
			<td style="width:111px;">Beckton-Dickinson</td>
			<td style="width:203px;">305136</td>
			<td style="width:691px;">Smaller needles (30G) can be also used. 25G may be a bit too big.</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;width:232px;">Clip applier</td>
			<td style="width:111px;">MiKRon</td>
			<td style="width:203px;">42763</td>
			<td style="width:691px;"></td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;width:232px;">9 mm Clips</td>
			<td style="width:111px;">MiKRon</td>
			<td style="width:203px;">427631</td>
			<td style="width:691px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:232px;">Clip remover</td>
			<td style="width:111px;">MiKRon</td>
			<td style="width:203px;">7637</td>
			<td style="width:691px;">Two pairs of teeth forceps (ROBOZ RS-8160) can be used instead.</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;width:232px;">Suture needle holder</td>
			<td style="width:111px;">ROBOZ</td>
			<td style="width:203px;">RS-7820</td>
			<td style="width:691px;"></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:232px;">Suture</td>
			<td style="width:111px;">Dowist Gell</td>
			<td style="width:203px;">5-0 Dexon S 7204-21</td>
			<td style="width:691px;">Can be substituted for any 4-0 to 6-0 absorbable suture with a narrow curved needle.</td>
		</tr>
		<tr height="34">
			<td height="34" style="height:34px;width:232px;">Glass capillaries</td>
			<td style="width:111px;">VWR</td>
			<td style="width:203px;">100 ul calibrated pipettes 53432-921</td>
			<td style="width:691px;">It includes a mouth aspirator system that only requires to attach a 0.22 um filter in the tubing to be ready to use. More information can be obtained in ref. 8.</td>
		</tr>
		<tr height="37">
			<td height="37" style="height:37px;width:232px;">Burner</td>
			<td style="width:111px;">KISAG AG</td>
			<td style="width:203px;">Typ 2002</td>
			<td style="width:691px;">Gas operated burner, can be charged with Kigas (CH-4512, from the same vendor). Alcohol burners may be also used, but gas provides a higher temperature and this burner provides a small and precise flame.</td>
		</tr>
		<tr height="105">
			<td height="105" style="height:105px;width:232px;">Stereomicroscope</td>
			<td style="width:111px;">Leica</td>
			<td style="width:203px;">MZFLIII</td>
			<td style="width:691px;">This is an expensive estereomicroscope with fluorescence, that can be also used for other purposes. There are cheaper options such as Leica MZ8 or Nikon SMZ-10 or SMZ-2B, to name a few. It is better to use two stereomicroscopes, one for handling the embryos (which does not need to be a very nice one) and another one for the recipient. The one used for the recipient should display a long distance from the stage plate to the objective lense, in order to be able to focus 3-4 cm above the stage plate (where the oviduct will be placed) and still leave some room for the surgeon; most of the stereomicroscopes can do this, but some cannot.&#160;</td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:232px;">Fiber optics ilumination</td>
			<td style="width:111px;">Dolan Jenner</td>
			<td style="width:203px;">Fiber lite</td>
			<td style="width:691px;">To iluminate the surgical area. There are different systems available.</td>
		</tr>
		<tr height="52">
			<td height="52" style="height:52px;width:232px;">Warm stages</td>
			<td style="width:111px;">American scope</td>
			<td style="width:203px;"><a href="https://exch.mail.umd.edu/owa/redir.aspx?C=1qTJKejamUSfudeYG_MlZHvTY3dsJM9Iaqr2SnwGD4ECWGzB8e8Rpg--_L7u0vJmyatXQJzGQ0k.&amp;URL=http%3a%2f%2fstore.amscope.com%2ftcs-100.html" target="_blank">http://store.amscope.com/tcs-100.html</a></td>
			<td style="width:691px;">These can be placed over the stage plate of the stereomicroscope. Some modifications (inserting a stick to level the stage) may be needed if it is too short for the stereomicroscope. A big warm stage can be used for warming the cage if it is available. If not, a regular heating pad can be used, but temperature must be checked.</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:232px;">Culture dishes for embryo manipulation</td>
			<td style="width:111px;">Falcon</td>
			<td style="width:203px;">353001</td>
			<td style="width:691px;">351008 may be also used, they made narrower drops.</td>
		</tr>
	</tbody>
</table>

utero-tubal embryo transfer and vasectomy in the mouse model

The transfer of preimplantation embryos to a surrogate female is a required step for the production of genetically modified mice or to study the effects of epigenetic alterations originated during preimplantation development on subsequent fetal development and adult health. The use of an effective and consistent embryo transfer technique is crucial to enhance the generation of genetically modified animals and to determine the effect of different treatments on implantation rates and survival to term. Embryos at the blastocyst stage are usually transferred by uterine transfer, performing a puncture in the uterine wall to introduce the embryo manipulation pipette. The orifice performed in the uterus does not close after the pipette has been withdrawn, and the embryos can outflow to the abdominal cavity due to the positive pressure of the uterus. The puncture can also produce a hemorrhage that impairs implantation, blocks the transfer pipette and may affect embryo development, especially when embryos without zona are transferred. Consequently, this technique often results in very variable and overall low embryo survival rates. Avoiding these negative effects, utero-tubal embryo transfer take advantage of the utero-tubal junction as a natural barrier that impedes embryo outflow and avoid the puncture of the uterine wall. Vasectomized males are required for obtaining pseudopregnant recipients. A technique to perform vasectomy is described as a complement to the utero-tubal embryo transfer.

Utero-tubal embryo transfer provides a mean to transfer embryos to the uterus avoiding some of the complications associated to the uterine embryo transfer2,9,10. In Table 1 we show some representative result we have obtained transferring CD1 blastocysts subjected to different kinds of manipulations to CD1 recipients following the protocol described. The survival to term (% of embryos resulting in a pup) or survival to E15 (in the case of lentivirus exposed) is similar between embryos simply cu...

Watch this Scientific Journal Video about Utero-tubal Embryo Transfer and Vasectomy in the Mouse Model at JoVE.com

Utero-tubal Embryo Transfer and Vasectomy in the Mouse Model

Utero-tubal embryo transfer uses the utero-tubal junction as a barrier to prevent the embryo outflow that may occur when performing uterine transfer. Vasectomized males are required to obtain pseudopregnant recipients for embryo transfer. Both techniques are discussed.

The transfer of preimplantation embryos to a surrogate female is a required step for the production of genetically modified mice or to study the effects ...

utero-tubal-embryo-transfer-and-vasectomy-in-the-mouse-model

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Biology

46.7K 조회수.  United States Department of Agriculture.  자궁 - 난관 배아 입금 자궁 전송을 수행 할 때 발생할 수있는 배아 유출을 방지하는 장벽으로 자궁 - 난관 접합부를 사용한다. 과 vasectomized 남성은 배아 전송 pseudopregnant받는 사람을 얻기 위해 필요합니다. 두 가지 기술을 설명합니다. 