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Wolfgang Kahn Veterinary Reproductive Ultrasonography Horse· Cattle· Sheep· Goat· Pig· Dog· Cat English Translation and Revision Dietrich Volkmann· Robert Kenney www.vet4arab.co.cc by Dr.Stator & Saraajka

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WolfgangKahn Veterinary Reproductive Ultrasonography Horse Cattle Sheep Goat Pig Dog Cat English Translation andRevision Dietrich VolkmannRobert Kenney www.vet4arab.co.ccby Dr.Stator & Saraajka, , I I I WolfgangKahn VETERINARY REPRODUCTIVE ULTRASONOGRAPHY Horse CaltJe Sheep Goat Pig Dog Cal Th.l._one www.vet4arab.co.ccby Dr.Stator & SaraajkaVETENAltY PRODUCTIVE IJ I Til ASONOGIl APHY Horse Cattle Sheep Goat Pig Dog Cat Dr WolfgangKahn Ellglish TrallslatiollalldRevisiol1 Professor Dietrich Volkmann Collegeof VeterinaryMedicine CornellUniversity, USA Professor Robert MKenney School of Veterinary Meclicine University of Pennsylvania, USA schlutersche Avk:lrSkoL a s ~tellO gradivo www.vet4arab.co.ccby Dr.Stator & SaraajkaWolfgangKahn. Dr. Dr.habil. Professor Cli nic of Reproductive Medicine.Veterinary Facuhy Uni versi ty of ZUrich.Switzerland English Translation andRevision Robert M Kenney.DVM,PhD Professor School of Veterinary Medicine Universityof Pennsylvania. USA DietrichVolkmann,BVSc. MMedVet (Gyn) Associate Professor College of Veterinary Medicine CornellUniversity.USA 0 2004.SchlUtersche Verlagsgesellschaft mbH &Co.KG,HansBOc:klcrAllee 7, 30173Hannover E-mail: [email protected] Printed inGermany ISBN 3-89993-005-3 Special edi tion. Reprintfrom1994. Bibliographic Inronnallon publishedby Die DeutKbe Blbllothck DieDeutscheBibliolhekliststhispublicationintheDeutscheNationalbibliografie;detailedbibliographicdatuan:: available intheIntemetllt http://dnb.ddb.de. The author assumes no responsibility andmales no guarantee for the use of drugs listedin thisbook. The author I publisher shallnotbeheldresponsible for any damages that mightbeincurredbytherecommendeduse of drugs or dosages con-tained within this textbook.Inmany cases controlled research concerningtheuseof a givendruginanimals islacking. This bookmakesnoattempt10validnleclaims madebynuthors of reportsfor off-labeluse of drugs. Practitionersare urged to followmanufacturers 'recommendat ions for theuse of any drug. Allr i g h l ~reserved. The contents of this book both photographic and textual, may not be reproduced in any form,by print, pholopnnt . phototransparcncy,microfil m. video, video disc,microfiche.or anyothermeans. normayit beincludedin anycomput er retrieval system.withoutwritten permissionfromthe publisher. Anypersonwho does anyunauthorised actinrelation 10 thispublicationmaybeliable 10 criminal prosecution and civil claims for damages. Avtorsko zas!!: !e'lO gradivo www.vet4arab.co.ccby Dr.Stator & SaraajkaContents Preface 10 fi rsledit jon Preface 10current cdilj on J 1.1 J2 1.2.1 Ultrasonoin the mare ............................................................................................. . Techniue of ultrasoninthe mare Ovarian slOIct uresinthemare "" """"" .""""" "" """ """" "". ""."""""" """ """". Eollicies .. ",,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, ,,, ,,,,,,,,,,, ,,, ,,,,,,,,,,,,,,""""""""''''''''''''''''''' ,", ,'".,2, .,',.,', ______________ ,So ,',0,es of follicles ......................................................... ............................. . :'".,2, .,',.,2, _______________ ,Dcve "",,',follicles .......................................................................... :'".:2, .,',.,3, ___________ "__ .T" m, ,osv , c,a,inal sonuncture of follicles ............................................................. . 1.2.2lutea ......................................................................................................................... . :'".,2, .,2 ".,', ______________ , SO " .hieimaes of cofa lutca ............................................................................ . 1.2.2.2Dcvelopmcni of corpora IUl ea during the estrous cycle andinearty pregnan9' h.. h, .. .1.2.3Anovulatoluteinized follicles ............................................................................................. . 124 1.2.5 1.3 1.3.1 1.3.2 1.3.2.1 1.3.2.2 1.3.2.3 1.3.2.4 1.3.2.5 Fallio d!!r a nd ovarianhe malOmas Ovariantumors andIS .............................................. ......................................................... l llenne Slruct ures in I bemare"",,"' ",,,,,, W h ." "h'"""." ,,, . ,,, , ,,,, ., "" ' ",,, "' ,,, . ,",, . ,', . ,,, .,"",,, """, ant uterus . " "" ... ".""" .. h .. "..... "" .. ",,, .... ,, .. ,," ........ ,,h" ........ ,, ..... "h" .. ""... h". antuterus ..... " ..... " .... " ............ " .......................... " ..................... ,..... ,........................... . Da Da Da Da 9 to l 30f 14t0200f 21 to 40 of .. "............. "...... "... "".. "...... "...... "...... ".... ""........................ .. ...... ".............. "..... ".... "............... h.. "" .... "....... ".. ".. "...... ",,. ..................... "...... "... "."h" .. h" .... h."" ... "..... "... h" .. "".... "" .. "................................. , ..... , .................... '.. , .................... "... . 1.3.3. 1.1Head,neck andinal column ................ " ...... " .... " ............. " ................... " ........... .. 1.3.3.1 .2lborax nndheart "' ..... " .. ".; ......................... "' .......... "'''' " ... '"'..... " ... " .. ""'. " ...."' ... . 1.3.3.1.3Abdomen andlvicreon ....... " ..... " ..... " .... " .... " ................................................. . 1.3.3.2Accessibiliof euine fetuseslransrcctal son.. " ............. " ..... ," .. "" ,... " .. " ..... "". felomelinhorse.c; ................... " ..... " ..... " ..... " ........................... " ................... . _____________and braincase ........ " ................... " ........... " ..... " .................... " " .... " ... " ...... " ............ .. 1.3.3.3. 2Ribs, trunk and stomach.""... "".. ,.""""",,,,,,,.,,,,,,,,.,,,, ... ,.,,.... " .. " ... ,.... " .. " .. " .. " .. " ...... ,. 1.3.4.2......................... "........................ "............... , ..... , ...... , , ..... , ............. . .... .. .... .. " .... """ " " 1.3.4,5muco- and urometra .. " .................................. " ................... " .... " .... " .................... .. _____ , _____ ,c__ .E " 0,d,,0, m ,,e,,',n",ai "IS", .. "" ... "" .... ",.".", ... ",., ... ", .... ", ... ,"... "",.""", .. "", ... ", ...... , .... "",.""" reface., .. ,.. ",.,. ,... ,., ................... ,.,." ,..... ,................. ,... ,'.,.,." .... " ... ,.. ,.. ,., .. " .. ",, .. ", .. ,.. ,.... "", .... ,." 2 2.1 22 2 2 J 2.2.1.1 Ultrasonoin the cow ... "..... "... "... "hh .. ".. .... .. ...... ..... "" ..""" .. "" . .... ".... "..... """ .. "" Teehniue of ultrasoninthe caw ............. "..... "............................................................. . Ovarian Slmctllres intbe rIl!.V""""", " ." ". "."" Follicles Soooes of follicles " ............... " ..... " .. " ..... " .. h." "" ......... ", ".". "h ..... """.. "" " " 15 15 '5 ' 9 23 25 25 27 33 35 37 41 4' 43 43 43 49 5' 53 6' 61 63 65 65 65 67 7' 5 77 79 80 83 83 89 89 89 www.vet4arab.co.ccby Dr.Stator & Saraajka2.2.1.2 22 13 2.2.2 23 2.3. 1 Co Follicular developmemduring the estrous cycle and inearl Estrous foll jcles ...................................... ............................................................... raIUlea ......................................................................................................................... . .... IUleaduring the estrous 9'cle and in early pregnancy .................................................... ...... .. I llerine Slnldures inthe CCttN ..................................................................................................... ......... .......... .... 2.3.2.2Day 21to 24of pregnancy..................................................................... ............. ......... ... ____25to 30 of 2.3.2.4Da31 to400f .............................................................................................. ............................................................................................ 2 "."' 3.,, 25 "'--____-' D"' a41to 90 ofrenan....................................................................... ....... .... ......... ... 2.3.2.62ndand 3rd trimester of pregnancy ......................................... ............. ......................... . 2.3.2.7Twin and multiIenanctes ...................................................................................... . 2.3.3Uterine........................................................................................................... ........ 2.3.3. 1 ok death 23.3.2 2.3.3.3 2.3.3.4 2.3.35 2.3.3.6 Eetalmummification...... ....... Ectalmacemtion ..... . ...... ........... ....... ... ... . .. ... ... Po.and llppruximlltelyJonintothl:follK:Ular tmtrum. Jolg.1.20: Corpus lutcum (:lrTOYo"S)whichdC\elopcd atthc si te of Bfollicleth:u had beenpuncturt.'tl-Idays pn.'"ViousIy. .-ig.1.19: depK.1ingthehcmorrhagc(be. "''Ccn theinto a foll icle3 minutes after apuncturehad beenperformed. Therealtimeimagedearlyturbu-IeIKCS(arTOYo)insidetheaccumulatedbloodiIIusU"atingthe inflow of moreblood. www.vet4arab.co.ccby Dr.Stator & Saraajka1.2_1.3 Transvaginalsonographic puncture of foll icles Tranwaginal follidepunctures can be used to collect nuidfrompreovulatoryfolli clesortoattemptthe collectionofOOC)'Ics.Thesameinstrumentationthat wasdesignedfortr,lnsvaginal concept us punctures was appliedforthispurpose(seeChapter1.3.2.6)usinga similar technique. The automated puncture device. cov-ered bya protectiveplastic sleeve, wasintroducedinto theanterior vaginawhereitwasgentlypushedag.1i nst thevaginalwall.Using IIrectallyintroducedhand.the ovarywasthenbroughttowardsthelipoftheultra-sound prolx:.When itwasevident on themonitor that thefolliclewasalignedinthedirectionof andfor the correctdepthofthepunctureneedletheautomatic puncture device couldbetriggered(Fig.1.18). Using thi.lutionandIIICrineAuld ... poq1WIC)'me. in....Mwith normal ..,.;l rilll IQlponum (MIlany qo- Thethinfollicular wallsurroundingthe\'CSicies can be rt!cog.nized in some of thefollicles (No.I and 4). fig. 2.18:(}.tarycontainingacysticoorpusluteum(arrows) andadiestrousfollicle8daysafterthelastQ\'UL'llion.The cavity of the corpus luteumis surroundedbya ...."llllof luteal tissue. Dorsal and to the lefl of it is the diestrous follicle (inner diameter: 17 x 13 mm). FIg. 2.20:Multiple follicles on an ovary9 days after the stan of ECGinducedsuperovulation.Thecowreceived3000IU ECG9daysearlierand05mgeloprostcnol7daysearl ier. A v ~SkOz.~10adlVo www.vet4arab.co.ccby Dr.Stator & SaraajkaI I Follicularvesicleswithdiamctcrsofmorethan10 mmcanbeeasilydctectcdusing5MHzult rasound (KAHNandLEIOL1986).Theaccuraterecogniti onof vesicleswithdiamctcrsof onlyafewmillimctcrsde-pendsmostlyontheimagequalitygcneratcdbythe scannerandontheexperienceof theoperator.If the examinationisconductedcarefully. follicles inthesize rangeof 5to10mmcan stillbeidentifiedreasonably accuratcly(Fig.2.17).Underlessfavorablcconditions the differentiationbetv."Ccnseveral small, neighbouring follicl es maynotbe possibleinevery case. Whencounting ovarianfolliclesbyultrasonography thereis a tendency to count10 to 30 %fewer follicles in thc size order of 3 to10mmthan are actually present . Vesicles with a diameter of less than2 to 3 mmaretoo smalltobe detectable. evenal thehighestresolution of 5 MHz ultrasonogmphy. When carefully petfonned the ultrdSOnic detennina-tionoftheinnerdiametersoffollicl escorresponds quitecxactlytotherealsizesof thefollicularcavity (QUIRKetal.1986).Thetotal outer diameter of the same follicle, including its wall. L"then 2to 3 mm larger. From a di fferential diagnostic point of view one must beabletoseparatethecavities of cystic corporalutea fromfollicles (Fig.2. 18). The sonographic images of the Follicles91 cavitiesincysticcorporalutearesembl ethoseoffol -licles.Incont rasttotheancchoicfollicularnuid.how-ever,the.mechoicfl uidcontentof thecorpusluteum cavityissurroundedbyamodcratelyechoicwallof lutealtissue. whichisa few millimeters thick. Follicular development can also bemonitored ult ra-sonically inhonnoneinduced superovulation (Fig. 2.19 and 2.20). In this way the number of developing follicles can beassessedreasonablyaccuratelyandtheir ovula-tionwithsubsequentcorpusluteumfonnal ioncanbe confinned(DRIANCOURTet al.1988).Theultrasound image of theindividual FSHor ECGinducedfollicle is notdifferenlfromthatof aspontaneouslydeveloped follicle.Onlytheoverallpictureconsistingof several. equally large vesicles is characteristic. Aflerovulationhastakenplace.theovulationde-pression. or any ot her signof ovulation,cannotbede-tected.Duringearlymetest rustheechographicimage of the ovary corresponds 10 that of an ovary without any significantfunctional structures.An ovulationcan only bedetectedinacowthatwasexaminedbyultrasound on the dayspreceding the ovulation,In such a case, the absenceofalargevesicle,whichhadrecentlybeen present. indicates that an ovulalionhas occurred. A v l o r s ~ ozaMeno cradi '0 www.vet4arab.co.ccby Dr.Stator & Saraajka92Ulrrowllogmphy ill rhe cow " U14 . ---S12 o10 E, E 6 .!i o E "2 .-"0 17 -u " .-- -. Ll 0 E E "0 -7 0 E " , .-" \7 0 -U \, .---. \, 0 E E "0 7 -0 E .-, " , 1,1 1.)- ........... L...argesl follicl es Second lugesl follicles-,.-o1214S6789101112Il14IS1617181920 Days afler ovulati on 2 follicular waves per estrous cycle Ovulation Ovulation + . , ....-." .''. ". .'' . .'. .', .', ... .' + \" '. ' . ... ' .' . \7 _. 3 R - I I3 2-, \ 71921013S79111315170I214 Days after ovul ation 3 follicular waves per estrous cycle Ovulati on + Ovulation ..... .... r---".. .. , " I ./ , + 1719013S79II13IS17190J23.j Days after ovulation tlg. 2.21: The dc\-clopmeruof thediamelersofIhclargest andsecondlargestfoll iclesin heifers duri ng the estrous cycle (fromKAliN 198IJc). Ag. 2.22: ThedcI.'Clopmcnt of indr.idualfoll iclesinahei fer wi thtwofonicularwa\"CSduro ingtheestrous l)'CIc(adapted fromSIROISandFORTUNE 1988). Fig. 2.23: 'Thedevelopment of individualfolliclesinahcircr with three foll icular waves dur-ingthe l)'C1c(adapted fromSIROISandFORTUI"E 1988). Avtoozascc1Ogradivo www.vet4arab.co.ccby Dr.Stator & Saraajka2.2. 1.2Follicular development during the estrus cycle and inearly pregnancy Folliclesgrow on theovaries :Itregularintervalsof severaldnys. Thedevelopmentof the largest folliclein each caseis usually inversely correlated tothe diameter of thesecondlargcstfollicleandtothenumberof all Olherfollicles(Fig.2.21).Duringthefirst3 daysafter anovulationthelargestfollicleonapairofovaries usually only has a medium diameter of 5 to 8 mm. After thntitdevelops rather rapidly to renchit..maximum di ameter of 12 to 14mm berwcen Days 7 and10 and then becomessmalleragain.Whilethedominantfollicle grows,the second onebecomes smaller, and visaversa. Alsothe number of thesmaller, sonogrnphically visible vesicles is inversely correlated to the development of the dominant follicle. The highest numbers of small follicles are found during the days following an ovulation,i.e. in metestru5(MAlTONetal.1981.Pt ERSONand Gll"'fH.ER 1984 b, KAliN1989 c).When a diestrous folliclebegins todcveklpthereafter.thenumberof smallerfollicles rnpidly declines. Thisrontrastingpattern of thedevel opmentof dominantandremainingfollicles W'olSfound incyclic as wella...early pregnantheifers (PI ERSONand GINTHER1984 band 1986). The growthnile of thelargestfolliclefromthe time itbecomc...dominantuntilthedayitreachesitsmaxi mumdiameteris, onaverage,1.5102.5mmperday (DRIANOOURT et al.1988). This growthrateis the same for dominantfolliclesduringthelutealphase,forcst rousfolliclesduringthelastfewdaysbeforeovulation and forthosefolliclesthat develop after induced super ovulation. Folliculargrowthincattleoccursinwavclikepat-terns. Atthetime of ovulationanother vc... iclei...grow ingtodevelopintothedominantfollicle,togrow furtherduringmetestru5andtoreachitsmaximum diameter during theearly lutealphasebetweenDays 4 and10 of thccycle. Shonly after thisdicstrousfollicle hasreacheditsmaximumdiameter, thesecondfollico-Poifides93 lar wavcstans andanother dominantfollicledC'oelops. Inthe case of a 2-phasc follkular cyclethis onc willter minat einovultltion(Fig.2.22).SomeC:ltlleshowtI 2-phasc, others a 3-phase pilttern of d"Sprior 10AI(from KA" s1989 c). FIg. 2.26:Cross sectionthroughthe solidcorpus lot eom ana-logous 10 the sectionalplanein Fig.2.25. FIg. 2.28: Cross sectionthrough Ihe COrpu... luleum "ilh ClI\icy analogous to the !iCClionalplaneinFig. 2.27. Ayr S0 zasc10;JradlVo www.vet4arab.co.ccby Dr.Stator & Saraajka2.2.1.3Estrous follicles The avcr.lge diameter of the cavity of the estrous fol-liclc at the time of standing heal is15mm(PI ERSONand GIIfflIER1984 b,KAHNand UIDL1986). When its wall I is incl udedIhismeans thata preovulatory folliclehas a totalsizeof 18mm(QUIRK et al.1986).Therangeof I theinner diameterof estrousfolliclesonthedayof standing estrusisJOto20mm(Fig.2.24).Itisnote-....'Orthy that pregnancies can resultfromlarge follicles of I 20 mm as wellas fromsmallfoll icles of 10 mm. Thedailyincreaseinthesizeof theestrousfollicle duringthedaysprecedingovulation is1.5to2.5mm. I Most estrousfolliclesthat havebeen studied by ultrn.so-nography rcuchedtheirmaximumsizeonthcpenulti-mate duy before ovulationand did not grow largcr dur-ing the 36 hours prior to ovulation. 2.2.2 Corpora lutea 2.2.2. 1 Sonographic image of corpora lutea Corpora lutca are rcrognizcd by their size and shape Iaswellasthei r charactcristic cchographicappearance (PIERSON and GINTHER1984 b. KAHNand 1EI0L 1986). I I I I I COI]HJmIlIlea95 Thesonogrnphicsection of lutealtissueappearsasa roughlygranular.gray-structuredovalareaonthe monitor(Fig.2.25to2.28).It canbedelineatedfrom thc remaining ovarian t ~ u eorother functional Slruetu-res that maybe on the ovary.Therelat ively hypoecho-genidty of thcaetr.'Ccorpusluteumisin distinctcon-trasttothebrightergrayof theovarianparenchyma. TheJalterusually containsSC\'Cml\'CSicular Slrueturcs of v"dI)'ingsizes.whereasthelutcaltissuecontainsno fluid. exceptinthe case where it oo'Cloped a cavi ty dur-ing its devc1opmcnl. The ....'Cak cchogcnici ty of lutcal tis-suecorrespondstoreflect ionstypicallyproducedby loose, less dcnse. highly vascular soft tissues. The highcr echogcnicity of thc ovarian stroma.incont rast.reflects its solidcons.istcncyandhigher tis... uc density. Corpora lutcawithcavitic.... socalledcystic corpora lutea. canalso be diagnosedbyultrasonogmphy (PI EH--SONandG II\"f1!ER1984b,REEVESet III.1984,KAHN andUIDL1986.Krro ct al. 1986).Ina corpuslutcum witha cavity anechoicrimof tissue, afewmillimeters thick,surrounds a central.anechoic fluidaccumulation (Fig.2.27). The ecOOgenici ty of therimof tissueisthe sameasthatof luteal tissueandthuscorrespondsto that of solidcorpora lulea. Alibi'flr a ~n www.vet4arab.co.ccby Dr.Stator & Saraajka96U/tnlsoflogrophy ill tile CDII' Fig.2.29: A solidcorpus JuteunIor theC)'tk(size:28.5"18 mOl)wilhahypercENand DElAll UNTA1985 b) Theearliesttimeatwhichpregnancyc:mbediag-nosed dependsverymuch on thesoundfrequency ,lI1d thequality of thescannerused(Fig.2.87and2.88). Usinga5MHzsc:mneritshouldbepossibleunder practical conditions to demonstrutethe embryonicves-iclewithrelative ease by Day 25.Fromthis Day the ab-sence of fluidfromthe ut erus indicates wit h reasonable certainty that the cow is non-pregnant. If. in addition to the embryonic fluid. the embryo is visible u posi tive con-finnation of pregnancyhasbeenobtained. Under cer-lainconditions thedelection of an allamoic membrane afewdaysprior 10the detection of theembryoispos-sibleandmaybelakenas1Ipositiveconfi nnationof pregnancy. Whileitispossiblewithu 5MHz SCimnerunder field conditions to deliver a reliable pregnancy diagnosis betYlCenDays25and30.this isonly possible ata later stagcif lowcrfrcqucncyprobesareused, duetothcir poorerresolution(TAVERNEetal.1985.aMFFAUX etal.1986.HANZENandDELSAUX1987).Withafre-quency of 3 to3.5MHz, thedemonstrationof the em-bryonicvesicleandtheembryoisusually delayedby about5 days.Ata frequency of 3 MHz theembryonic vesicle is visible after Day 25andthe cmbryo after Day 30 (TAltmJRIER et al.1983). Studies on thc accuracy of ultrasonicpregnancydiagnosesindicatedthatatlow frequenciesof3or3.5MHzanaccuratenegative diagnosis could bemade byDay35to 40 and a positive diagnosis not earlier thanfromDay 45 (TAVERNE etal. 1985, CHAFl--AUXet al.1986). AvlorSII:OzaMeno cradi '0 www.vet4arab.co.ccby Dr.Stator & Saraajka126UlrrtlSQllogmphy ill tlte cow fol g.2.89: COIlCI:ptUSwilhcmbryo(indamnion(21lIT(J\\'S)on D:ly33of pregnancy.Thcamnionathinmcmbr.Ulc whichsurround\the embl)'O.Uhrasonogrumproduced \\ilh sector sc::mncr at 5 MI "' il(. 2.91:Conceptus with cmbl)'O and amnionCA)on Day 40 ofpregna ..Theheadofthecmbryo..... iththe;mcchoK: round area of thc dc\'cloping cye (arrow) lie.:.tOwards the left. Thec:tl:M11rump- lcngth(CRL)is2Umm.Ultrasonogram produt'Cd wilh..ector sciinner lit 5 Mi ll. Hg. 2.90: PholOgrnph of lin embryo wi th surrounding amnion and3djoining311:ulIochorion(AI)onDay37ofpregnallC)' (specimenrcmO\'Cdfromtheulerus). foig.2.92:UltmsonogrJm of (Ioooccplus wit h embryo (E) and a singleplaccntome (P) on Day 33 of pregnancy. The plOlccn tomebudlikeinto thelumen. SkO.t.e"lO0 www.vet4arab.co.ccby Dr.Stator & Saraajka2.3.2.4Day 311040 of pregnancy Thecrown-rump-Icngth(CRL)oftheembl)'O reaches12mmaroundDay 30.15mmbyDay35and 20mmbyDay40(PIERSONandGINTImR1984a). Qmlsiomilly aroundDay 30, butusually aroundDay 35 theamnioticvesiclebecomesapparent(Fig.2.89and 2.90). A few millimeters away from the embryo it forms :1 ....crythin. arched,hypercchoiclinewhich surrounds the embryo. Around Day 40 the mean diameter of the embryonic vesicleisabout2.5emandtheCRLofthecmbf)'O about2 em(Fig.2.91). The sizes ofcmhryonic vesicles vary,hninc "J990j.Gcn-echoicband of th.!'l'inalJIMnrn)Y"_2.11+0,00215 , 2(63--201) (Wmm)y. 7.7&.0.191.(61-211) ,. -29_1O.0.62:h(60-211) (lg. 3.1S). 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