Studies in sex physiology, No. 17. The extent of the gravid Merino uterus in relation to the vertebral column in the dorsal recumbent position and the weights of the gravid uterus and foetus in relation to the general body weight

Understepoort j (1/11'/1(/l of r !'tCI·itWI',IJ Science and Animal bu71lslry, l"o7mne 7, .YwnlJer 1, Jul.1;, 193G.

Studies In Sex Physiology, No. 1 7 .

The Extent of the Gravid M e rino Uterus In Relation to the Vertebral Column in the Dorsal Recumb ent Position and theW eights of the Gravid Uterus and Foetus in Relation to the General Body Weight.

Hy H. II. (' HSO:\ a111l J\. J>. :JfALA~, Section:; of Siatislics aud Anatomy, Oncler~tepoort.

l.xT Hom· en ox.

TnE ob~el'Y<llion~ lllaclr in I'Ollneclion ,,·itli ihe 1·elaliou~hip of the gra1·icl uterus io the Y('l'tf'hnd <·olumn :ne of aca1lelllic inte1·f'st, in ihai <hning liff' ih<' utc>ru~, ,,·hid1 occnpie~ a Yenhal <lhclolllinal po~i­

iion is separate<l from the> Yf'rtehral rolumn h)· thr stomach and

inif'~hne,; li i~ ne,·edhelP~s in~tl·uctiYP to note il1e illnP<bing aren

"eo,·ei·r<l "(*) hy the ulentR of thr Y<niou:; i11ierYab o£ preg·nan<·.\'.

Jlcnlil'ulndy ilw (']'<Inial li1nil of the clP,·eloping organ.

0£ gre<der ini<·rest is the ratio no( onl~· het.11·E'en il11' \YPio·ht of

!he graYid u(eru,.; to i.hr g<'llf'rnl ho<l~· "·right (minu~ ilH· "·<'ig·hi of il1e unopent•d 1d('J'u~); hut :tlso thP n•btionship het"·re11 tlw fo1•hil ,,·eight <lnll !he g'E'IIPr:tl bod,,· "·eight of the moihPr (:tlso minu,.; thr weig·ht of the 1tnopf'nerl uterus).

Ll'I'EH.\'ITill·:.

\rorb on oh,.;telrics, r.y. Crnig (1D00) :t1Hl ·wylllan (HlOl), naturally refer to iht> 11sual rf'lations of tl1e enlarg-ing uteru.-;. Crnig-

\]1. 104-) stales iltai. " in lLLlllinanL tht• graYi<l utPnb pa,.;,.;ps into ilw

<1bdo1nen and rxten1ls het"·ee11 the right sac of the l'llllll'l1 :tnd thP :th<lominal wall ". \\~ymnn :tdos (p. I) tlwt "the mtterior frep eud not supportNl hy lhP hroad lig:nnents is ('OYne<l b~· the greai ome11tum " .

- - -- - - - - - - - -- -

* 1.0. \\'hen the e1re is in the clor'ial recumbent position.

2Gl

S1T IJJES IS SLX .l'l-IYSIOJ.U(;y, !'\0. 17.

'l'he photo;n·alJh:; accompan.1·iug our Stud_,. unfortuna1.oh·

illus(Tate only the in!'n'ase of size of the u(Pnt~ in rdation to th<e lmnhar :nHl ihorac.;i!' Yer·tebntf'. llamrnorHl (19:$:2), 1dtile uot !'Oll- cenle\1 "·ith the positiou of tl1e uterus in tlw ahrlnrninal t·ayi(y, gin'~

useful infonu:tlion rPgarding the luralwr region of ;;beep. lie indi- cate:; (a) in 'l'able LYIJ (p. 21G) that· the lnmhar formula of his anilllals '":1s u~ually (), :1ntl mPntion,; (b) that· " thf' Yariahility \Thieh exists in i he lulllbar and also of the thoracic ,-pr(e!Jr:le . . . sho"·s the possibility of lllC!'easing lhe COll!Jlar:tfiYe ]png(h of this lJ:ll'i ]J_\- seledion ··. liP a(l(ls (c) thnt ·' it app(·an; probable . . _ thai thP seat of grPate:;t po~t-natal grmdh o(·t·urrPd <lL the Pnd of the lhor:l('ic and beginning· of the lunrlwr region., );"athusiu::; (quote(] hy Hanrn1ond. ]J. :!ID) shlh?s that tlw :u·(u:il lf'ngth of the lt1111hnr region is intlPpenden(

ot

the nu1nlwr of lurnhnr· ,-el(Phr:w, lnr( ^:b Il:1rnnwntl poin(,; out. hf' does not g·i,·e thf' relati1·\' le1rg·th of lumbar region (o othf'r par(~ in (hf' ~hPep unrler (·on;;ideralion.

Jrt rt•g·nnl to _gToiT(h in foel:1l ,,·pig·ht thPre is but litil(• inftll- 111::dion :tl·ail:thlt•. Tn fad, .:\Pedharn (1!):31) stat!':; thnt. "C'olin i~

the onl_,- inYe.-;tigaior "·lw .h:ts eYPr· dPtPrmirlPd ··this bctor. The figure he repnHluc·ps (Fig. :)!), ]J. TiD, \'nl. 1) .-dro11·.-; the \l'f•ight :1~

a per(·eni:tge of thP sys(!'Jll ot·!'upil•d h_~· tiH· e!llhryo, foetal llH'Ill- lnarll's and frwt:d fluid,; ancl not a» a pPtTPrda;.n-· of the \\·eight of i he e"·e.

(a) Sisson (1911, p. 15G) gins the w1·tebr:tl formula of the .

-;!Jeep as ('1, '1'11. T,G-1, S--1 :1ncl ("_~· l()-18, hut our eXJH•rience 11·ith the ~Jeri1ro sho"·~ that. J, 7 is mon• cornmon than LG. Also in the :1rlult, o"·i11p: to the pradic-e ·of cloc-king lambs, tlu• rnmrher of co('(·y- geal segnlPnts remainitJg is lPss th:l!l half the• normal 11umher.

The tletail~ bear·ing on the rPhtioJJship refenf'rl (o in the title :u·e _, um11 r;nisPd in ^'1':1 hre T.

The inne:J-;p in Yolurnp of thP utf'rtts lll<l-'-lw juclgPd by penrsal elf Figs. J, :i, ·\ S, 11, :tnrl I :J; hut it 111<1~· he rHl(leJ that "·her·('<b the .~Tea(r.-;( tlqlih ol tlw JJOn-gru,·id u(t•rus ^i~ :t]ljli'()Ximatei,- 0 ('Ill., nnd J(J c·r1r. af(rr one nwnth ·~ prrgnan(·y, thi.-; f1gure hns inneas(•tl t-o Fl rm. :1t full tf'rllr.

It must lw PmphasisPtl thnt thf' l.JOd\· of ih(' utr•r·us i.-; exu•C'dingl_,- short. (ahou(· :2-:1 rn1.) hut o11·ing· to thc· JIOSLPrior part of thC' hmns hPing unifl·d h~- conrlel:ti,·e tissue :tnrl haYing· a c·onJJnon pPritoJwnl lining, a fabP iclea nta)· h<' ohi.aiilPd as to thP f'Xtl'n( ol' the hocl_,-.

(b) Frolll t·olunlllS (2) :llld (.f) haYP hf'f'll ('<JkulatPcl the JlPr-

!'Ollt:tge \YPip:ht of the intact or gTa,·id uterus to the g·ener;tl hody

\\·eight.

'l'he "·eight.-; of the unovened uterus, expres.-;pcl a:; :t percentage of the weig-ht of tl1e e'"e (les,; ,,·eight of unopeued uterus) ['l'ahle ] , colunm (G)_I, arP represented graphi!'ally on the ac·t·ornpanying rhart.

It is to lw uo(etl that the n lues in 'l'nhle I. columns (-!) and (G).

marked 11·it h a11 asterisk, are approximntf'ly tlouhlP tlH' Yalne to ^])f' Pxpeded fr-om ^:t conqJarison of thf' 11·holf' series_

262

11. IJ. CURSOK AC\D ,\. P. :\[ALAN.

T,\IILE I.

====;~

- -

(1) (:!)

:'if umber- of ewe.

Live

·weitr!Jt

o f

CW('.

(hg.)

(:3) (+)

\\"('ight

- ~----

(;)) I (6) ^!I (7) I (8)

I

\\'ei"ht

\\'eight of r~n- \Voight ¹

of ewe opened of foetr" Pre- les~ I uteru,; 1as a pcr-1 Xu 111 her

I

^sacral

weight as a per- ccntagc ~ of vertc- of ecntagC' of the '1Ium har brae utcrns I of the weight vNte- ·coYct·cd'

un- weight of the bt·ae. by

(9)

I

Stage of of un- gesta- opened

tion. ) uterus (Days.) (Cm.) ( ll)

I

^{opcnccl.l of the} e11·e (1" ). utcn". (J\:g.) e11·c (1").1 (0-j,)

(Oo)

28.)8±. :18 .. )li \'on- 1.)8 I ~ (s(•e

I . ~ravid fig.:!) .

:2.)\)2-J.. :38 .)6 :3 16:~ 38 :I!J 0 + ^(I 00 I 2 (sec

fig. 4).

:3.)71 '?. 21 ·++ ^{:31 16;) 27 8:2 0 6 0 00 I .)}

38.310 ... 38 78 ^:).) 870 37 ^{!)] ·> :;} 0 11

:3.)6:)\). :3+ 1:1 61 2,000* 3:2 I :1 6 ^•)* 0 :2:2 ⁽ⁱ 7 (sec fig. 6).

:33.3!12. 31 7:) 64 1,440* 2!) _·03 4 8* 0 21 7 (sec

fig. 7).

331:3[.. :33 ^·:)7 !l:? 2.0()0 31 ·-II G 6 I 9G I

I

l l (,;ee fig.!)).

:3990±. 3\J +6 9± 2, ];)5 31 ·31 5 ·8 s·' ⁷

1

9i (sec fig. 10).

329G!J .. 38 ·10 107 2,!)82 35 12 8 ^:) ;~ 76

35976 ... 3;) :;s 12:2 :3,380 3:2 00 10 6 G 97 7 I ^{12 (soc}

1_!:140 I

fig. 12).

45023 ....... 42 ·8() :3,700 37 16 15 :l lO 09 7 12

- - - - -- - - -

(") This includes vtdYa Yagina, fallopian tu bcs and ovaries. In Stuclv 12, colu11111 4, the heading ob,·iously should re<'cl '·Approximate total 11·eight of unOJWiled utcms." There the weight inc-luclerl the oviducts and ovaries.

(Ill) Les;; weight of unopened or gravid utcru<.

Fnnn Par] iPr ohsen·ations (Sex l'hY~iologT, Sturh ] 0) ii <lj)j)P;n;;

thrtt the wPipJtl of i he unoJWllPrl niPrn.--; ( l•:,n· 1f\0) at <1 gesb1t ion <~ge

of G-± <lays is 1,0()0 gm.,"' in whic-l1 r·nse the \\·eight of ilw unope1wrl uirrm; is approxim;~tely 8·2!-J pPr r·Pnt. of ihe " eig·ht of ihe e"·e. This ,·alue. 3-2,) JlPr cent., is also sho\\·n on tltP ch;nt hy ;1 squnre dot and eYidently lies Y(~r,v ne:n thP PXJWde(l Y<ilue.

Ignoring the ,-aluPs fOJ' (il [Jnrl (i-J- (hys, gi·n·n in 'l';~h]e I, column (G) alttl m;~rkPll wiih <111 n~ieri~k, n smooth r·cnYP h:ts been dr;nn1 throug-h the rlab, ib equ;ttion being-:-

7/=0·00131 .?"¹"87 ',

"·here .-,. = _r;cstoh.on ]Jeriod. 111 days,

100 ^{1re£_r;ht of 1moprncd 1der11s,}

1j= X .

· II"CI_!Jllt of thr eire-let. of tl1e 11110penc

7

ute1·1tS.

- -- - - - -- -^~-

*Subsequent!-'· (3.2.36) ew<' 301G!l \Yas kiliPd on Gist cla~- of prPg;nanc~· nncl the Y>eight of tl1c u nopetwcl u tprus 11·as 1,192 gm.

263

I

S'l'l)IJIJ·:S lX SI·:X l.'JD:SIOI.OGY, Xo. 1/.

CHART 1.

\Yeight of (a) the nnopened ntcrus and (I!) the foetLb as a prc<·enbge of the 11·eight of tho ewe.

17 f---'---1 -+----+-1-+---+--+--+---~--+---+-+---+---+----+---i

lh r----:- -t- --+- --+- -+- -+- - + - + - + -+ - +- +-- +--t--17---l lo

lsl--t--t---+---+--+--+--+-~-+-+-+-+--+--~; r - - -

L-- t --+-+- +- +--t-- 1--t- -+- + - +- t -- r--- I --r---

1< I I

tJ f--t---+--+---+---+---+--+---+-1 --+-+--+---+---+ / +---t---1

1---t--t--t--t---+---+--+--+-~-+-+-1-- I -+--+-~

12 I I

I

^I

II 1---tf---t---+-~--+--+--+-+-+-+-+-+/-+--+-~-~

!

!

1 :~

r---t--+--+--:- -+- -+--t-- +--+--1--- ;' /

-+---+ ;6 -

: - -J---t----t----'!i:'----+---t-- +- f - - -1-0

//9 .1#

" 1---+-+---+--+--+---fp'-'-r '()'--+- -+-- / -+-+-

/ 0

s 1---t--+-+---t---l--+--+~/ / +---+-- t,

/ II

• ,:---t---t--+--+--+- --.--1 /

I

^{--+ - + - +-- +--1}

I /

~

)

"'

· ' -i---,---- /

^{+ -+-- +---'/}

, I : ~ / ( rt----1-~· +---+--+--+---+--~

I

_; / ; [ I

^t I

l

0 10 20 JO ·HI SO 60 70 SO lJO 100 110 120 13() 140 150

Jhys.

Tl1e \l·eig·ht of the foeLuc;, Pxpre,.;,.;<•d <It> <l pel·<·<'JILtgP of t IH' ""·e 11eight [Tahlt• I 1·olunm (I) J is also repre;:;P1Jlel1 on the dJ<Id. 'l'l1<'1ie poinb an• joined h:v a lif'ries of stml.r;/,1 linf's. It is io hP ohse•n·pd th<Jt the foetus wPig-hts for (il and (i.J. d<J.n; sho11 no snch irregu[;nity

;Js 11·as ohsC'I'I·ed in thP \l'<'ip:hls of the unopent•d uteru:;. Thi"

strengthe11;:; thP conclusion that the <lisn PJ1<lnriPs nwniionf'<l aJ·p lJJOI'f' lib-'l.\ duP to <Ill L'ITOI' than to inlli1·i<lual Y<lriation.

St· .\lC\1.\IIY.

The inc.:n•<i'lll/2.. p:-;tent of tl1t> PJ<IYid utPrus is 11·ell illu:-;trated in the Figs. l. :;, :). ~. 11. ;mel 13, and tlw reLdionsl1ip [:wf' colunm (!J) of 'l';1hle

Il

to ihP w rtehrnl nxi,; in Figs. 2, J, (i, 7, 0, 10 ancl 12.

The 11·eighb of the 11nopenNl ulen1s anrl of the foe(u,; alone are expi·f' . .;.;ed a.; Jlf'l'<·Pntage:; of the P\\'f' 11·eight (minus unopt>lwr11ilf'J·us). Details are :;pt ,]mnl in l'olunln,; (!i) and (I) of T;1ble I ;mel '' <lia-

!!l:lllllll<Jti<· J·pprE'~Pnbtion i:; g·i,-pn in ihf' l'hart.

2G4

II. I-J. C"CRSOK AXJJ A. P. :IL\L\X.

HEFEHE~CES.

CRAIG, J. F. (1930). F/rminu's r etrl'inul'lf 0/,.,trf,.ics. Rlilliere. Tindall &

Cox, London. 4th J~dit.

CTHSO'\, H. ]-{ .. AXD QtT:-\L.-\\" . . J. (HJ:l-1). b<'X Physiology. Stnd,· 10: The•

Situation of tho ckn~loping Fo<>tus i11 the Mf'rino She<·p. Onrlerslet!OO!f ./1. f'rt. 8c. <I· cl11i111. lnilvst. 'i·ol. 2. "!\o. 2.

CTHSO'i', l-1. 1-l., .IXLJ :\[..\].,: \ ' \ . A.P. (193,)). Se,; l'h,Y.siolo)!:\·. Study 13. The changing proportions of tl1e :\l1•rino J,nmb from tl1e st•i·oncl to the fifth :\Ionth of J:'renatal Life. !11id. \·ol. ·k Xo. :2

1-1.\111:\IOi\D, .]. (JH:\:2). (il·o,rth ond flu' ])r,.el''i'"lent of J!ultnn I.Juoldu•.< in lf,e ,'-:heep. Olin•r :md Hoycl. ·London.

XI•:EDl-lr\.\f. .f. (l0:ll). 1'/ii'JOiml E'"''ryol()i!!t (:·l \·ols.). C':1111hrid!:':l' l·nin•rsit.'·

J'nlss.

\\'L\1:\S. \\'.E . . \. (1$)()1). /ioci1u' (iiJoll'iric.> /,!/ Jl. 1:. ,/,. Jl,IIU!. 'i\'illi;!lll H. Jenkins. Tra nsl:~tecl h:· \\'.'·man.

Furtl1e1· to the <lata recor<lecl nhoYe, subseque11i oh,;erYntion,;

];nYe heen made n~ follows:-

(o) The extent ol lhe Yertel1ral :;;.;is " r·oYered ., hy the gTaYi<l uteru.s (t-he f'\Ye being· in thf' clors:;J. rerumlwnt po;;ition) at the Y:n.ious

~Ltge,; of pn··.Q.·nan<·y i:; :iho"·n in tlte follo11i1lg i:thul:!terl Sllnlmnn· :-

:J.>SI!-1.

-1-1803.

-(.)082.

HS-19 ..

1.-,:!:37.

:!1665 ..

-1-1619 ......... . :J8i'i2l ......... . -1-13!)7.

:l05l4.

8/(Jge of f/eslatiou.

:J:? da ,., :l:l . 60 GO

!)0

no

I :?I l:?l 14;) 1-16

J1resutro/ rerl<,hrue

· r·on-rerl ''by uten!S.

+

4 6 (j l.l 9 14 14 1:3 l+

Tn the.-;e ohsf'lYations, <1S in the former se1·iPs. thco nnnial limii of the uien1:; \1·:1.-; detc-rmined o/teJ· the stomach and inibtillP:i had loeen n•mon•rl. UbYionsly if de.termined hcfme J·enH>Yal of til<' ,-i,;- t·ern, the n :tn.i:d lin1il ill nth·nncerl pregnan('ie:; ,,-ou!tl not \J;JY<' heen

:iO fnr :Interior 011·ing to tlw influenre of tlu-• int<•rpo:;i11g· otg:ll1:i. A-; 11·oul<l he expPd erl ihere is a n·eneral <i"Tf'eiiH'IIl lwh1·p~·n t];p

(;hren·,;tion-; rer-ol'lled hen' nnd in l h; fo;·,ner ~<·rie,;_

(b) In reg<ll'd to ihe relat-ionship het11·een lhe (i) gr:1Yi1l utPrU:i and (ii) foeh1s, :111rl the e11·e "·eight less 11eight of gT:IYirl uteru.s e;.;- presse<l a:; <I pc-n·entr~ge, the additional ebb, I.e. oht:tillP<l h on1 tlw e11·es :1hon•, ,,·i.ll be inclu<le<l in a further rhscussion on I h~· ,;uhjec;l in Sex Physiology Study 18.

265

STUHJ:s 1_x SI·:X l'llYSIOI.O<;Y, _xo. Jl.

Fig. l.- E11·o 385-(8, non-pregnant. Ycnhal Yie11· of uletus.

(±.\ of origin:d.)

Fig. 2.- Bony peJ,·is of ^J·:~~·e :l8-3 18, non-prl'gnant.

'Jho uterns <·~tends oY"r 21 pr<•sacr:d ,·ertcbrne.

(±~ of origin:1l.l

'2GG

li"ig. 3.-l~:w0

,-Jew of gr;n·lcl ( ±

±

of original.)

II. IT. ClJllSOl\ .·~XJJ .·~. 1'. :\L\J .. \X.

:259:2-1, pregnant 31 cl::tys. Y<·ntral uterus, right horn pregnant.

Fig. 4.- E,Ye :z,3():2~. The :31 clay.s pregnant uten1.s extend, on:•r 2 pre,acral ,·enehrae. (± l of ori;.;;inal.)

267

S'JT DlES IX SEX PliYSIULOGY, .\"0. 11.

Fig. ;).-l~11·c 35G59, pregnant Gl. days.

Yit•w of gra1·id uleru~, left horn pregnant.

origi nnl.)

268

VenLral ( ± -~ of

H. H. CURSON AND A. P. MALAN.

Fig. 6. Fig. 7.

Fig. 6.-Ewe 35659. The 61 days pregnant uterus extends over 7 presacral vertebrae. (±1, of original.) Fig. 7.- Ewe 35592. The 2 months (64 clays) pregnant uterus extends on~r 7 presacral Yertebrac.

(±! of original.)

269

S'JT DIES IX SEX l'llYSIOLOC;Y, ?\0. 17.

l•'ig. 8.- 1•:\\'(' :]:ll81. ]Jf'<"gtwllt D:Z d;t\'S. v,•ni.r:d ,-iew of gra\·id utf'rii:-;. rigltt horn pregna11t. (±.~- of original.)

210

II. H. CL'JtSO::\ .1:'\ll .1. 1'. ~\1.\L.I::\.

l~ig. 9.

l<'i~. (l.- EII·c· 3:31:31. Tl"· D::' (!,"-~

""tE'Il(ls u1·er 11 fli'P,:Icral ,·ertc•bra;·.

l<'il-!;. 10.

preg11a11l ui.<·rw'

( ±! of origin:d. l

l'io- 10.--1·:"-'' :l$)})0-1. Tlte :) 111untl1' preg11ant uteri IS o~"ll nd' ul·er D} JHCS:Jcral n•rLebr:Je. (± ',

or

original.)

271

S1T IJU:S 1.:\ SI·;X l'llYSIOT.Q(;y, :-.-o. 11.

l<'ig. 11.- l;;wc :1.)0/6. prE>;.;nant J:U dny,.

\~Pntral Yiew of gra1·id 11ten1s, ldt horn pn·gn:~nt.

(± .', of originnl.)

272

II. H. CURSON Al'\D A. P. MALAN.

F1g. 12.- E\re 3597G. The four montl1s pregnant uterus extends o,·cr 12 presacral Yertebrae. (±! of original.)

273

·s·ITIJILS 1:\ Sl·:s l'liYSIOI.Ol;Y, .'\0. ] 7.

l'i<Y l:l.~l·:,re J.)0:!:1, pr<'gnant about U9 days.

\-<',,t,-,;r ,.;,.". of gr>11·id uic•rus. l .. rt born prf'gnant.

274