Anthelmintic tests, chiefly with tetrachlorethylene, for the removal of the hookworm, Gaigeria pachyscelis, from infested sheep, with observations on the effects of this drug on other parasitic nematodes

Ondetstepoort JoUJ·nal of VeteTinmy Se1'enee and Animal lndustty, Volwrnr 7, !V?imlier 2, ()r·tolier, Jf):)G.

Anthelminthic Tests, Chiefly with Tetrachlor- ethylene, for the Removal of the Hookw orm, Gaigeria pachyscelis from Infested S h eep, with Observations on the Effe cts of this Drug on Othe r Parasitic Nematodes.

By H. J. UUTLl·:PP uml ll. U. ~[Cl.\'XIU, Sedwn of Parasitology.

Onrlen;tepoort, Son th A fri.r::1.

DuiUN<< the coun;e of i nn·.~t ig;il im1s h1· one of us (H . . j. (J.) on tbP life hi~t·or)·, motlP of ~pread and preYt>ntion of ihP sht-•t·p hooh\'llr·m- Goigrrio ]JOr.ftysr·eiJs- the 1ni.ter.~ hnn·. \YlrPrr lll<ileri:d be('allle aY<Iil- ahle, tried Y:lrious thugs in an attelllpt to find a suitable medinmt for the remoYal of this p:n;bite horn infe~terl shPt··p. The dn1gs nrainlY e.xperinJt•nted "·ith wpr·t" l'hemi<·all,v pHre C::1rhon 'l'etra- ('hloridP nntl Tetr;!chloreth.\·lt·ne, 11·hile n-Hutyl-Chlori<le, Extrad of

P\Tethrnm ;m(l other ('hPJJJi<·;ils \I'PI'P ::1bo tried. 'l'he i11·o first- ll~me<l <lrugrs h::J~e•, sin('e the rese:!rc1Jl•,; -of Hnll :lllll Shillinger, etc., lwen Pxten.,il·el)· used in the frp:~hueJJt of hmn:m,.; <I!Jd <logs inft-•decl 11·ith hook\1·orms, tlw fornwr b;1ving been fonnd hv thesP \Ym·kers and b)· D;!ulme)· (1910) to he nbo YPr~· effer-tiw in the treatme11t of sheep infeste1l \l·ith the ftook\\'Ol'lll n1/110.dOI7/IIIII [JJ,Ij01/UI'C}Jllllf11111.

n-Hutyl-rldoride wns ieRt-ell h~- \\'rigl1t <111<1 8rh:dfe1· (1D82) nml fmmcl to be S-1- p1-•r <·ent. efft>di1·e for the l'PlllOY:Il of hooh1·m·ms hmn 1log-R.

Pn·ethn1m i•xh:td \\·as h iPrl lwr·:ntsP of its knm1·n ldh::Jl :1rtion on

,., ; 1 a

hloo<led :cnim;ll~ anrl it·s harmles~ness 011 w:1rlll hloocled <Ulitnnl~. anrl in Yi.e11· of the f:1Ynur;1hlt> Teports on ib pffirf!n· ap:ainst hook-

1\·ornt~ in rlog·s hY other nni.hors.

In the first series of tPsts IS <Hlnlt Pt>r~i.an ~ltPep 11·en• nsPrl, ;ill of '"hi('h ha(l h)· fae1·al examin:1tion heen fo11ntl to ^rfllT\' a ht-•avy inft>din11 of Goi,~;cn·a pacltyocclis. 'l'hes<·' shePp lwrl h<><'ll hmit;·hi from .\Lr. Y. Theophilns, Puilimot>. 'dtPie t-II<·\· lwrl <ll'quireil a n ::1tural infection on his f::JI'lll. Of t hPSP .~ h eep t e11 \\·pre rlosecl 11·it h

899

.IYI'li.Jo:Ulll\TJII(' TESTS.

tetraL;Itlorethylene in an equ::d .-olume of meal "·ater, six \\·ere aosed with carhon tetrachloride in an equal Yolume of meal water and two

"·ere kept a,; control~. The following- tahle giYe;; the result:;:-

:'\t~mbcr

of Sheep.

a6429 .. 364-10.

36437. :l6H:2.

:i6-i~6.

:~6427 ...

:i6HI :16-i:!fl. 36-(:3:). 36+4-1.

a6±3s. :{6-(:33. 36-U5 ..

36436.

364:11.

:~6-i34.

364:1:2.

36+43.

D1·ug. I Quantity.

I

C',C I, 3 e.c.

'f c.e.

5 c.c.

,.

. , 10 ^{(' .(' .} CCI, 3 ^C.l'.

-i c.c.

;) (' .('.

., Untr c-atcd.

T.-l.i!LE I.

\Yorm., passpd d11ring next

:~ cbtyH.

!)

1 :!+

Egg:; in faeceH l:l days

nftcr drug.*

ttt-i·

tt titt

ttt

tti

ttt

itt·i tH HH ii'tr

ttt

ttt

Htt

·it!

ttH

ttlt

ti't

t Few eggs p1·csent (l-10 on slide).

·[·i· Fair llll!llbN of q!gs present (lJ-!iO 011 slide).

ttt ^~[any eggs present (51-100 on slick).

ttH )/umcrous eggs present (o1·cr 100 egg' on slick).

H<'mark.-.:.

Died 13 days after closing. 1:24 li ,. ing Gaigeria colleeted.

Died 1-i cla.1·s after dosing. 12:1 living Gaigeria eollected.

Diccl night after closing. 77 li 1·c Gaige ria colleclccl.

Died (i cLtys <tfter treatment.

\·\'or IllS not collected.

Bag.s \H're tied on t hP ;;heep :1 Her do::;ing- in .order to colled all the fa pee;; ]J:t~;;t>d; the faece:; ,,·eu· carefully ~~-,bbeu and ;;[eYed and all the 11·ornt~ pa:i;;erl during the fullo1Ying tbreP days were collected and counted. ln onler to detPnttine the ]Jre;-;pnr·e of egg-s in the faecPs, all!l1l(· 2:-J to :)() g-r:tm.s of fre;;h faer·es wpre t:tkrn fro111 Pach .-dreep ..-it!ter rlired from the rPd um or from the hag. Tlrese 11·ere then wPll hmkPn HJl in i:tp \\·:t!Pr anrl thr·n p::t~serl throng·h ,.;pyeral :iieYPci to rei:tin the coarser mnte1·ials. l<:ar:h wac; then placed in an F:rlennre.\er tla,.;k anrl :tllo,,·ed to ;;ett-le. The S1tpern:t!ent liquid \Yas then c:trrfully pourer] oft :md thP rPttt:tining srclimrnt \\':l:i tto\\· mixerl

"·ith :tn r-•qual ,-olullle of g-l~·c-erine and "·ell sltaken. It was tht'n cPn(rifugPrl in :1 tulJe 8 em. rlt>ep anrl 3 ern. (liameter, for about :3 minutp,s :tt alJOut 1,000 reYoluhon,.; pe rminute, IYhen the eg·g;; l'O:iP to tlw top of the 1 iqnirl: these \\·ere then pie keel up 11·ith a fbt hottomN1 gl:h.s rorl :1bout 1 r·tn. rliameter anc1 seYI'ral (-t to :)) rlrops werP tntnsfpr-r,•rl t·o a slirle :111(1 pxaminerl minoscopie:tlly. As the G'a,r;erio Pgg-s :trP much largPr :tn(l clarker than tho,.;e of the r·ontiiiOll round \l·ornH of sheep (Hoemonrlws contoPtus, Trichost1·ongyl?ts spf1.

anrl OrsOJ1hnqosfoll171111 r·olumln.ruwm) the~· eoulcl e:tsil.v lw recognisPrl.

-1-00

1!. J. ORTJ~EPP AND H. 0. :110);::\l(;.

From Table l it will be seen that doses of :3 to 5 t;.c. of Carbon tetrachloride had 110 effect on the remoYal of the worms;

closes of ;) to 5 c.c. arH1 10 l:.<·. Tetrnl:hlmethylene also hurl Yery little effect, although three of the sheep did pass out some worms, they ueYertheless still 1etainecl a good infection; three sheep which died how one to fourteen da:'i·s after dosing sho\\·ecl living hoobYorms on post-modem, ] 24, 23 and II worms being collectecl respecti Yely. 'l'hP ,;heep which had receiverl 10 e.c. !HISsed no "·orms and still remained heayiJy i11fected. Sheep ;~G4;J(j treated "·ith <;arbon tetrachloride cli<>cl six clays after treatment an<l through a misunderstanding the \Yorms were not c·ollPdecl. The t\YO f'ontrols also passed no '"onns and remainerl hea 1·ily infested.

PreYious i·o i.rPattnent the sher.p harl free accr.ss to ha:y aucl broken maize, ancl a week prior to treatment they daily received ahont 2 pouncls of a ~~: 1 mixture of hone u1eal and salt, while maize was removecl. Foocl or 11·atr.r \Yas not kept away from them bef01·e m· after treatment..

Three weeks after the nLove hentn1ent six of the aboYe sheep

\YPre again treated with Carlwn tetrachloride and 'retrachlorethylene, nncl fiye '"ith n mixture of Pqual parts of these drugs ancl two were l\P]1t as !'ontrols.

The follcminog table giYes tht> rr.sults:-

N mn bcr of Sheep.

Quantity.

'1'.\ llH TT.

vYorms passed durin a

followi~g 3 days.

Eggs in faeces 10 clays

after dosing.

Hemflrks.

~~~--;-~~~.;.-~~-'-~~~...;-.~~~,---~~~-· ~--- - - 3643.~ .... C2CI1 6 C.C'.

36444 ....

36438 .... , 36437 .... CCI, 36425 ....

:{64iH .... .,

( CCI,

3644l. .. ^~ and :{6428. l ^C,CI,

:~6433.

:~6434 ... 8 c.c.

36426 ....

, I ,

36432 .... Untreated controL

36443 .... ,. ''

ttt tttt Ht+ ttt

Ht ·:tt

tH

4 ttt-r

tH

3

ttt

tHt ttt +tt

Killed following c..lay. 39 Jiv.

ing Gaigerin collf'ctecl.

!lied 2 clays later. 167 liYing Gaigeria c:OIIf'eted.

Died 2 days later. 65 Jivin)l Gaigeria collected.

Except for the last two sheep treated, the clasP \Yas in all c·ase,;

mixecl "·ith 12 c.c. meal water; in the last hYo cases only 10 c.r. meal water "as aclclecl. Sinc~e the first treatemnt all the sheep hatl free arc;ess to hay and the salt ancl hone-meal mixture, also they 11·erP not kept awa~' from food or "·a ter before an cl after closing. ThPv '"ere all in a very poor c'on clition. ·

401

.INTJ-LEL~Ill'iTIIIC TESTS.

Table ll shtm,; lhat 6 c.c. of Carbon tetr;u·hlori<le ot·

'l'etrachlorethylene in meal '"a ter ha<l very little or no efted on the remoYal of the hook11·onns, h1·o ~~-onJIS onh· beino· retnoYed autl all the ~heep still remaining he:wily infested a·s sho\Y~ by egg flotation. One of the shPep ~~-hich ,,·as Yery 11·eak was killed the following day.

<lllrl on post-nwrtelll 39 living &fli.l)cna 11·ere f.ouud adhering to i:ht>

ntu<.;ous memhrnne. Of the 0 slwep 1dJich 1·eceive<l G and 8 G.C. of a mixture uf ec1ual amounts of thesP t11·o drt~gs 2 sheep passed 4 an<l 3 hookiYonns respectively rhuing i:hP following 0 clays. 'J'wo of them which cliP<l i11o <1:1~·s afler lre;1iment still h.1d 1G7 and Go liYing Gm:_IJI'n;a respectively, some of 11·hich 11·ere lying fr-ee in tl1P lumen of the intestine. The tn·o controls pa.-;sed no worms and still remained heaYily infeeted. l t \Youlcl thu~ <l]lpear thnt a mixture of the,.;e drugs given in G :1nd 8 e.C'. dosPs is not t>:ffective for the removal of Gm;.r;eTia hookworms.

1\:-; the ,;]Jeep \\'Pre in a YPry pour <·ondition the\· 11·ere frulll now on fe1l on hay :mel ;1 li heral suppl~- of l'rushPd nwi~e plu::; hone-JnPal and salt. Tb<-'.\ pil'ked up g'l'a(lunlll in <'OlHlition, an<l during thP r.oun;e of the next seYPn 11·eeks n llumher gradually lost mosL of t11t:>ir infe!'!ion <IIHl two E'Yentuall_,-be<·ame free of hook>Yorms. Centrifuge egg Hotat ion <leterJnin:il ions afkr () and 7 ,,.Peks on this diet and faernl culture after () \\Peks g-aYe thP results sho"·n in the following- talJlP:-

T.-UIT.E III.

Gaigeria Gaigcria I

N11mber oggs eggs

of after after Ctdture. C. O.c. H.c. Tr. F>.p*

Sheep. 6 7

weeks. wccl<i:S.

:l642fl.

:16-±26 .. t I ^{\\' :!0 :34 14 3:!}

:{6431. t t

36432 .. l):t H ^{M 7!1 -5 12} +

:16434. )[ IG :22 ^;)5 7

:16437 ... 'l'i''i' ^{j·jt M l:2 35 5:1}

36438. tjt H·j· '\I 6:! 10 :!2 6

:16441 .. tt tt ^{\\' :10 14 :36}

:3644:1. i"l' 'l'i ^{M 50 10 30 10}

:!64-H ... ti H ^{_v[ 47 1 :)2}

* \1·= \\·cak Cll!turc: !li= medi11m cultllr<'. These refer to the dcnsilv of the lan·ac on

the sides of the bottle 8-JO days after cult11re. ·

G=C:aigeria: O.c. Ocsophagootom11m; H.(·.= l-laemonchiiS: Tr.=Tricho,trm1p:ylus:

S.p.=Strong_)'loicl<'S. The numh0rs giq~ the percentage of the differ<'nt l;inds in the first 100 Jan'>to counted.

For fiome inexplicable Teason no larvne developed in thP culture of fneees from sheep 36431, althougJ1 eggs werP present.

vVhen COillpnring these intensities of hookworm infection, as revenlecl by centrifuge egg flotation rletermination, >~·ith those of the flame sheep seven weeks pn'Yiou;;ly 11·e fin<l that h1·o :sl1eep havP en- tirely lost their infection (ttt to - ). bl·o lHlve lost two-thirds of

402

H. J. OHl'LEl'l' ANll IJ. 0. ~lONN.lG.

their infection ( t t t to t), two have lost half their infeetiou (tHt to tt), two have lost one-third of their infection (ttt to t J

one has lo~;t a quarter of its infection (tttt to t tt) and one has retained its 11·hole infection.

'l'he:;e shee]J huu now been in this experiment for fom· wonth,.;

aud during this period they had been kept in a dry pen alHl \Yen·

I'On~:;equentl,v not exposed to reinfection. The infection they still retained was that 11·hich they had brought with them. 'l'he rliminu- tion of thik infection may thus he asci:ibed to either of t"·o causes, firstly that many of the" parasites had already leached the end of their s]Jan of life and thus naturally rhecl, only the younger hook- worms remaining; or secondly by better feed the constitution of the sheep was improved with the result that they were able to riel themselves n a tnrally from a considerable portion of their infection. It is a fact oft~n seen in the field that wlwre the diet of sheep is improve<l, the sheep, "·i th the improvement of their ('onclition, tend to riel themsehes of a large proportion of their worm hunleu. In tile above ease both the above-mentioned canses maY ltu\'e lwen re- f'ponsible, hnt the writers are inr·lined to the view. that t}Je hettel'

<liet playerl the principal role.

As the sheep appeared to be rapi<lly losing their infection and as the treatments with Carbon tetrachloride and Tetrachlorethvlene had given ;mch disappointing results it 'n1s <lecidecl to dose s'ix of the still infeded sheep with 1 to !) c.c. of Stafford Allen's extract of Pyrethn1m M:.225, one sheep with ^]!) e.c. C"Cl, and to keep one sheep us a control. In all cases the dose 1n s mixerl with 20 e.c. o£

distilled "-ater and "·as administerefl ln· stomach tube. The 1·esults are ,.;et (Hit in the following· table: - .

:~6443.

:{6431.

:!6440.

3644-1.

364aJ 3643R.

36444.

3643:?.

umber of Sheep.

. ^. .. . . . ... . . . . . . . .

...

.. .... . . ..

... .... .

..

. . ... ..

... ..

Drul!.

Ext. Pyr.

,

c:c1

_Untrca(p

.

^I _d

TABLE IV.

Amount.

1 c.e .

"

:l e. c . 5 c.c.

., 1.5 c.c.

Control.

~umber of worms passed tlnrinf!

3 clrtys following.

:~

Eggs in htcces at treatment.

'i'i' tt

tt t

-;-n

t H H

Eggs i11 faeces 10 dnvs

afte;·

trentm0nt.

·r-;-

·n

·;·

t

·J·n

tt tt

From this table it is eYident that the int.eu:sit.y

o r

worm infes- tation remainerl about the snme before an<l after h eatmeni \\-.ith Rxtrad of Pyrethrum: it is true that after 10 (lays one of the sheep (:l()440) \\-hil'h had TeceiYe<l 0 cJ·. h:ul lost its infeetion (t to - ) an<l the other (36441) '"hich haJ recei"Yed the same close had its infection hahed (tt to t); no worms, hO\\·eyer, were passed <luring ihe en- suing three clays after treatment so that the loss probably took place

400

.\1\TllELMlNTlllC TESTS.

~ubsequently aJHl before dte tenth <lay ;tlter trt>allliPH(: tbi~ loss IYas probably due to Ilattu·al causes. lt thuR appeats legitittt<tl<~ to cOlt- dude that a dose of 1 to .) c.e. of };:-;.had ot L'yrC'! hru111 iu \\ ater, do~ed direct inh1 !he rulllen ha~ no effPd on !he expulsion uf tl.tP Goiuerio hook,,·onn.

Tht> RhPep \\·hidt lwtl I"el"PiYt><l 1--~ l".<·. of C"Cl, i11 11·n!Pr din='l"i into the rumen passed J hoob\·lnms, but the infe~tation remained Lhe ~a1ne. Tl1 e con h·o 1 sheep ~ho \\·ed no change.

A~ the hook\yonll in;e~tation of these sheqJ had no"· bel"Ollle ratlwr low it \\"<b cle<·ided to 1·ei nfect lhem ail ificialh·. Gnt:orlu- n<ltely during· this inl<~I"Y<tl sel"ernl of these silePp tlit·<l. "Tit<· Jettl<lin- ing- fe"· \l"t're ttot hu·!her PX]letittten!ed "·i!lt e.'\t·epl ott<' "·bit·h \\"<<S very " e;tk. This sheep \Yas rlosecl \\·itlt ]() <".<". t!"(Jl, itt I() t:.c. liquitl par;~ffin and. diecl i11o cb _,·s h lPr. So \\"Otllls "·en~ p:ts,;etl antl <tl posl-nlor!Pnt :):l4 living- Um_l)l'llll \\Pre foullll ~till ad hPring· lo the e<tn:t!l inte~liuP :tllll elr,·ett \\"Pre free in !he l:trg·e i.nle:-;linP, ot \\·hil"h S<'YPtl \\·PrP still :tli,·e. 'l'hr oiher sheep \\·en• ~Pl a~idP in order th:d cnltun~~ nt:t_Y IH· !llade front tlwnt to infed fn•sh .-;lu•t']J.

\\'hil<· :1 stock of infr;;!ed ~!Jeep "."" being prep;~red, thr llldhorl of adntinislering- \ln1g-~ into !lte ahottlrl~um of sheep, :tfler a preli- JHinar:v <lost' of <:Opper ,;n[plwlP ,;olu\i.on, hel":tllle knti\\"Jl (Hoss, 1904:

:\Iiinnig- antl lJ<1in, JHl--J). allll it

,,. ,h

^{t1Pt·i.det1 to tn· tJti.s 111}etitoc1 in fnturP P:qwriJtJPnts, ag-ai11 using 'L'Ph:td!loretbylene ancl also n-Hutyl- ('hloritle. :'\ine shePp 1\"Pre en•Hhl:tll~· ohlainerl \\·hit·h sho11·ecl a mo<lerate infestation b_,. thP eg·g- flobtion method. 'l'he:v werP (1iviclPt1 into three g-roups of tltrre each; onr group recei1·ed :) c.c. (\ ('1, in 10 e.c. liquid ]Jarr~ftin, tlw otber 10 r·.c. (',('], in 20 c.<". liquitl prlla- f-hn antl the third group 10 c.c. n-But~-1-Chloricle in :20 t·.l". lil]1Jitl paraf-fin. Immetliately prior to <losing end1 ~hrrp \\·as tlren<"het1 \1·ith about 10 c.c. of n 2 per l"ent. copper sulpl1nte 'olul ion. 'J'hP ~hPep

\\·ere 11ot .-;pecially prepared, ueii·her \\·;tc; foorl or \\·ntt>r kPpt <1\\·n~·

from thPm bt>fore or <tfter llosing·. The results of this lrealment are shown in the follo"·ing tal:Jle :-

=====;=--=====--=====;::::===~=

);umber of Sheep.

:;917:{.

:l9;"i88. :19998. 3972+.

:l099G. ...

4000!). . . . ...... :19184 .... 39+77. 39nl.

c,c1.

. .

ll. Hut. ('hi.

.-\mount.

;) c.c.

lO C.(".

404

E~g~ in faC'CCS at tr~atm<·nt.

Ht tt tt

~~

' I

tt tt ti·

·i·i·

ti·

l~uus in

f~~ces

J 0 day' after treatment.

"\H it i t

j·

H

\\" orms paRsed dttring following

3 days.

~R I!J :!:~

;) 17

R. J. ORTLEPP AND 11. 0. CIICl.\l'iJG.

'1'\\-enty days after treatmeut the faec;es hom the three ::;heep which had been treated with 10 c.e. 'l'etrachJorethylene were again axaminefl and >Yere again fouucl negatiYe for hookworm Pgg.~.

The results of tbis dosing appear to slHJ\\- that \\'hen dosed innue- diately after drenching with oopper t>ulphate solutiou a close of 5 c.c.

TetrachlorethylenP is not pftrdiYP for the I'elllOY<ll of ()aigeria hook- worms; a <lose of 10 c.c. n-B11tyl-Chlorirle ^1s about 50 per cent.

effective mHl a dose of 10 c.c. 'l'etrachlmethylene is Yery pffectiYe.

In order further to test the effectiveness of this dn1g the f.ou1· sheep which had pas:>ecl no \1-orms in the ahove test "-ere eaelJ clo"ed 'Yith 10 c.c. 'l'etrachlorethylene in 21) e.c·. li<juicl paraffi11 immer1iately after rhenching \Yith a \Yeak coppcw Slllplw!P solutio11 ,,-ith 1 he follmY- ing reRults.

'l'AlJLE VI.

Eggs in Eggs in

Number Eggs in faeces faeet>s

of Drug. Amount. faeces at 10 days 20 days

Sheep. treatment. after after

treatment. treatment.

39173 ........ I

C2Cl4

I

^{10 c.c. I ttt}

I - -

39588 ............

I

" " tt tt tt

39998 ........

" " ^I H ^{- -}

39731 ....•.... ,.

I

^{" I tt tt tt}

The >YOI'Jlls passed were unfortunately not ('Olleeted in these eases.

This result, although not so promising as the previous one, sho>YS that in bYo sheep all the hook,,-mms were remO\"ecl ,,-hile in the remaining b1-o the hookworm 1m rc1Pn \\'aS not red ul'ecl. In these hYo tests ''e thus haYe fiye sheep out of seYen freed of their hook,Yorms.

vVhat is especially striking is that these worms were either entirely dearecl or not at all. This leads one to su,;pect that in the fiye cleared sheep the drug pa~secl direct into the ahomasum nntl was thu~

able very soon to reach the hookworms iu the intestine, whereaR the clrug passed into the rumen in the othm· h-ro sheep, and eonsefJuPntly was not able to r·ome in ('Ontad with the hookworms immedinteh- and in conceutra tecl form. ThesP sheep also earriecl a fairly heav)~

burclen of "·ireworms ancl norlula1· \YOI'lUS aurl it \Yas striking that iu the five rle:1uecl sheep the number of strongyle eggs >Yas also reduced.

Having obtainecl these highly promising results with the dosi11g·

of 'l'etrachloretltyleue immediateb· nfter (lrenring with a 2 pe.:· ceJtt. sobHion of Copper sulphate, an opportunity was n~Ynited 10 t.ry nut tbis metholl of treatment on n large seale. This opporhwity srJon

·oeeurrerl in that ~Ir. Theophilns, \Yho l1ad been suffering very f!Xten-

sive Jos;:;e~ in his Persian Rheep due to this hookworm, ofreren to place his entire flock of abont 1,000 sheep at our disposal if we

"-ishecl to ('HJTy out an~· tests. 'l'his offer \Yas aecepterl and one of us (R. J. 0.) proceeded to his farm in the Vryburg district of the Cape Provinee. His adult sheep, about 480 in number, were found to be in a very bad state, Yery thin and Yery anaemic and a larg·e per- centag·e of them showed marked swellings under the jaw. Six ful]

405

.-\:\"TITEL~[ I ~X'J'l-HC TESTS.

grown ewes of these \\~ere taken and an examination of their faece6, taken from the rectum, showed that they \\·ere Yery heaYily infester!

with the Gaigeria hookworm and also \vith stlongyloirls. 'l'hey were then dosed with 10 c.c. 'l'etrachlorethylene mixed in an equal Yolmne of a light neutral mineral oil after drenching with 10 c.c. of a 2 per cent. eopper sulphate solution. 'l'wo clays after they 11·ere slaughtered with the following 1·esults:-

TAJJLE VII.

Xo. ^{of nrup-. Amount. Hookw. H.c-. Tr. O.c.}

I

^R.emarks.

Sheep.

1. ... C₂Cl, 10 c.c. Numero:1~ Allliv.inu.

2. Many Numero,·s Numerou'"

:3 ....

'J- .... Numerous Many Fair Kn.

.

') ... 1 (detached

in s. int.)

6 ... Numerous Many Many :V[an_v

The ab0ve test shrmed that drenching as aboYe cleaned hal£ of the sheep of their hookworms, \vhereas the 1·emaining three still remainerl heavily infested. In the three cleaned sheep wireworm and trichostrong-yles we1e also absent, \1-hereas in the remaining three both these worms were present. All six sheep were ;;till heavily in- tested with nodular worms. It would thus appear hom this test that where the drug is able to pass rtirect into the abomasum it kills not only hoolnvorms but alw wire"·orms and 1richostrongyles. In the three Rheep which remainerl infested the drug most probably passerl direct into the rumen.

The sheep were closed in the cool of the eYening- directl,y from the Yeltl. After dosing, which was done by means -of a suitable syringe with a long bent nozzle and squirting the drug gently down the sicle of the> cheek. all the sheep shmYed marked readions; all became some\\·hat gicldy and sluggish and three of them developed marked tympan~· of the rumen which had eventually to be relieved

b~· pundnring ,1·ith a trocar. Xext morning, hmn•ver, all six werE' normal again an c1 g-razing.

Sixty sheep ,1·ere now taken micl cliviclerl into l\YO groups of thirt:'i·-fiye and twenty-five sheep: their ag-es variecl from 2-tooth to adultR, and consiHtecl of e"·es only. Faeces from hYenh·-fiye \Tere taken hom the 1 ectmn nurl all on examination shmYecl Gaigm·ia eggs.

As the>:;e sheep had not been selected front the flock but taken at random, except that all lambs "-ere discarded. it appeared leg·it.imate to comlnde th;1t if not all ther1 a Yery l1iu·h perc•mtag-e of thP acluli- sheep rarried hookworm infeetion. In addition all the sheep showerl numerous stronp,·yle eg·g·s, probably H. contm·tvs, Tn'chosfl-onm;llts sp.

ancl Oe.wphngostomu111 col1tmln'nnmn as revealed by the post-mortem,;

on the sheep clisc·ussed above. The group containing thirty-fiye sheep was g·iven each i) c.<". C"Cl1 in an equal volume of a light minernl nil. while the other group receiYecl 10 c.c. C,CI. in nn equal Yolume

406

R. J. ORTLEPP AND H. 0. MONNIG.

of light mineral oil. Immeclia tely prior to dosing with this drug each sheep received 10 c.c. of a 2 per cent. copper sulphate solution.

These sheep '"ere dosed during the late afternoon direct hom the veld; during the evening it "·as noticed that some of the sheep in the group which had received the larger dose were slightly bloated and a trocar hacl to be used on one; the sheep in the other group showed no signs of bloating, althougi1, after dosing, both groups became somewhat giddy and sluggish. Next morning, however, all the sheep were again normal. Two of the sheep hom each group were now slaughterecl, 13 hours after dosing, with the following results.

'l'AnLE VIII.

Worms at post mortem.

Drug. Amount.

Gaigeria.

I

^H.c.

^I

^Tr.

I

^o.c.

c2c1. ^{;) c.c.} \fany Numerous Numerous Numerous

" " ^{" " "} "

" ^{10 c.c.} -- - - ·

..

" ^., -- ^{- -} -

"

'l'he two sheep which had re1:eived the larger flose showed no hookworms in the small intestine. Among the faeces of the large intestine, however, numerous dead hookworms were found. The other two sheep sho,yefl no deacl hookworms in their faeces.

The a boYe ex peri men t confirmed the results obtai ned at the laboratory (vide Table V), namely that a dose of 5 c.c. C2Cl,. was not sufficient to remove the hoobYorms, "·hereas that of 10 e.e. was very effectiYe. A large number of sheep "·as used in this experiment iu order to see whether blonting was generally associated with the administration of the drug, anrl if so whether it harl to be considered a serious reason against its use. From the above result the writers are indine1l to the Yiew that sheep aftEw adequate flosing shoulrl be carefully "-;~tcherl during the ensuing few hours anrl any sheep ;:;how- ing marked bloating ;;hould he relieved: notwithstanding this clra"·- back, it is felt that, "-ith careful handling·, 'l'etrachlOl'etylene is a relatively safe rhug for use, e;.;peciall:v for the reason thr1t sinC'e per- forming· the aboYe test, a large mnnlwr of doses haYe lweu arlmini- sterecl at the laboratory to sheep of clifferent ages, in poor nJl(l goorl condition, starYed and unstarYecl, \\'aterecl and unwate1·ecl, with and without copper sulphate solution, hut in not a single cnse was there any sign;; of hlnr1ting. (See also rliscussion on toxicity of Tetra- ethylene belo,Y.)

For the next test thirt:;·-eight sheep similar to and from the same flock as those used in the foregoing test "-ere used. These had slept overnight in a kmal acljacent to the shee]/ used in the foregoing test, and were dosed the next morning· after drenching with Copper sul- phate solution. Ear-h sheep received 20 c.c. of a half-and-lull£ mix- ture of C₂C1, ancl liu·ht mineral oil; these sheep "-ere then given free access to water, which they did not take. and placed in a nearby

407

.1.\TIIEI.~IISTHI<" TESTS.

paddock with plenty of gTeen grass. l<'or a ±elY hours the~e sheep kept tog-et Iter ::1nd a ppearetl Yery d ro"·sy, but other11· ise no seriou"

after-e:lfeds 11ere noted au<l by midday all 11·ere normal 81JU gra;~,iug-.

'l'h is PX)lPrilllent thus tended to slto11· that sheep 11·hich hall hee11 h·a:tle<l OYPI"llip;ht and dosed HexL Jllorning, \\"Pie less lii;Ply to hlo:tt than thosP IYhi<·h had bel'n dosed during tl1e late aHernoon dirr<-t honJ t hr Yel<l.

The rPsults so far obtaim•d in the fiel<l n·ith :.\lr. 'l'h<>ophilu~·

sltP<'fl 111:1y lw suJJllll:trisecl as foll01n;:-

I. Si:-.: :;pled<•<l adult shet·p and hl·euty-fiye adults tak<•n ltap-

lw;~,ar<ll,· sho11·ecl bv fael":tl rxan1ination thai ilwy 11·en• hadlv infestPt!

11·ith lw.okll·orJJJs: i.he probahilit.v 11as thus tl1at i't llot thr 11lwle :1dult Ho("k thPn a \Pry high persPIJLq .. n• of th<>m 11·as infpst<·d.

2. All tltesP ,;heep 11en• :dso hPa,·il_l, iufl'..;ted 11·ith 11"11<'-.

JlO<lubr- and trichm;trongyle 11·orms.

: {. or

^Pight shePp ll·hidl hnd rel"eiYeLl 10 (;.(;. U2C'l,j fi.ye lwd Ul\

post-JlJodPnJ lost all thPir hooh,·ornb. 1Yire11·orms :1nd tri<·hostrong:ylP worn1s. TltP renwining three still had all tlwse 11·onns. J\ll PiglJ!

::>tilllwd lll!JlJ<•rolls noJular "·onus.

4. Of tiYo sheep 1dtich hacl receiYed :) c·.r. C'₂Cl1 both on post- morteJlJ still c:Jnie<l a he:ny infedion of all thP alJOYPnantecl IYOJ"Jll~.

,-1. U appL·ar~ ~afer to clo,;e- the ,;hN•p in the Jllorning- :1ft<•r h:11·in.~

hePn kraa]pr] oYernig-ht.

(i. ,\s the• shPep "·hic·h hac! h1•<·ume <·ur<'<l of hook11·orms hacl lost tlwir c•Jdin~ \\·orJJJ lJllrcl<'JJs of the :lhOJll<lsllJ\1 ancl snJ:tll intL•.-;tinP, <tncl :IS (liP IIOII-l"lliPc"J apj>L:'<Il"Pd to h:ll"l-' J"PtaiJl!'(] :1ll t ilPS<', it aJlJlt'<II"S )ig·ii i- lll<JtP to <·one-lucie that thr PHPc·t.iYPDPSI> of 'l'etrac·hloJ<•thylenP is almo,;t <'JJtirPI_, clqH··nclPnt oJt 11·hPiher it reac:hes tl1P :JhonJas1JJJJ direc·t or not. This l"OIJ<"lusion is SlJbsinntiate<l b,· the results obtain<'tl bY tlH• clo~ing· of this chug- 11·ithoui pn·Yiou:'; ~lrenching- IYil h :1 Copp<;J.

sulphate> solution. 1dwrP tlw pffpc·tiYP11f'S,; of this <lrug- w:1~ ,;ho11·11 to hp n• ry lm1·.

As it hrul no11· hPf'n sho11·Jl that Tc·tnH·hlorpt !Jylc•np 11·:1s :1 n·n·

PffPl"tiYP :1nthPln1intir for thf' h·patnwut of Gai_qet,;l hook1Y0nn, pro- ,·iclP<l it ir-; rlosP<l rlirPd into tlw ahomns11m, it \Yas clecirlecl (o doH' tlw 11·holr floek, in hatclH•o; of :JI10ut h1·o h11nrhPrl <'l·ery llJOl'niJJg-.

Ead allult shPep wa~ to rPceiw the full <lose, i.P. ]() <'.<·. (;₂Cl.1 + 10 c·.c·. nPutTal JlliJJPI'al oil. 'l'hP <lo,.;illg" hrul to lw 1·epe>:lie<l three hn1rs :1t int·f'n :tls of 10 to 1-~ (b~·s, :md 10 <lay,; afiPr P:lc·h clo"ing- :-10 or JJJoJ·p hec·Ps s:\lllples lwcl to lw b kpn hoJ\1 the n•r-i l!JJJ hon1 a simil:n nuJnber of shePp takPn from the flock at l";lJHlom: thPsP f:tec·c-':; to hP PX<IIlliJJPcl mis<·Tsc·Ojlil":illY h1· thC' egg- rPnirifu.Q·<· flot:dion nwtho<l for t lw prPSPI!C"P or :dlsPnc·p of hook1nlnn Pggs. It was f'Onsirlererl that ,;11l"h :1 prol"PdurE' 11·oulcl g·iYP a •!·no<l inrlir-ation of thE' progTPs,;

of t lw <·un~ or otlJPJ"II·i,;p in thP ''"ho¹p fior·k after onP. t 11·o or thrP<~

h<•ab1J<'llt~. As h,·ent_,·-fiyp sh<'PP takE'n at random hacl alrPrHl_, . . ..;lumJl to l:P all infec·terl with hookll"mllls and ot-lJPl" stroug-yloid 11·orms. it appPare<~ leg-itimatE' to as~u111e that prior to hrahnent· all.

or a Yer_v hig·h perc-entage of tlw slwPp, werE' infer·terl "·ith botlt honkn·orms and otlwr strong~·loi<ls.

408

R. J. ORTLEPP ANlJ H. 0. ~101\NIG.

The do:siug- of the first ninety ~Sheep on the first day wa" done personally ann it was arranged that the owner should continue the first dosing and also carry out the required second and third treat- ments. The collection of the faeces was also clone under the super- vision of the owner, when 25 to 30 grams from each sheep were placed in a suitable tube in 10 per cent. formalin and ;;eut to the la bola tory for further ex ami u a tion. As the sheep fro ^Ill which the ,.;amplet> ''"ere taken weTe on each occasion taken at Tandom it is poi:>sible that samples from the same sheep may haYe l1een t:ollecterl on more than one occasion; the cbant;es. howeYer, m·e that on eac·h occasion the ~ h eep were clifferen t, or at least the gTea ter num her of them \Yere.

'l'he 1·esults afte1· these treatments ma,v be summarisecl as follo\YS:

A.ftrr lsi treafm.ent of 54 samples taken*: -

2;l ! 42 · () [lf'r c-ent.) \Yere free of hoohYorm egg,; (- ).

FJ (27·S pp1· c-ent.) ""Ple jnst po,.;itiYe for hookworm f'g·gs (t).

:) (:)·:) JWr eent.) had a ligl1t infection of hookworws (tt).

!) (l(i·(i per c·ent.) harl a fair inefdion of hookworllls (ttt).

4 (1·4 per !'ellt.) hncl a good infediou of bookwm·n1~ (tttt).

ln adllitiou all the sheep sho,Yed the presene:e of a considerable nullllJPr ·Of other nematode eggs (ttt to ++tt).

Aftrr 2nrl trrntlllt'nf of ^:)0 :'alll]Jles taken holll the whole flock : -

~l8 (7() per c·Pnt.) \\·ere free of hoolnYonu eggs (- ).

:J (G per t;ent.) \\'f'l'e just pohitin~ for hook"·o1·m eggs (t).

fi (10 per c·eJlt.) hat1 a light infedion of hoolnYorms (tt).

2 (4 Jlf'l l'eut.) hacl a fair iHfedion of hookworms (ttt).

2 (4 per ('ent.) h:ul a goorl infection of hoobYorms (tttt).

'With regard to other helmiuths these ~amples showed that:-

l() (:32 per ('ent.) "·ere free of all l1elminth Pggs (- ).

0 (10 perc ent.) ,,-ere ju,;t positi,·e for helminth eggs (t).

l() (:3.2 per ('f'llt.) shmYe1l a light hebninth infection (t t).

(i ( 12 pe1· ('f'nt.) shm,ed a fair helminth infec.tion (t tt).

7 (14 ]'Pl' r·e11t.) showed a good helminth infection (tttt).

A.ftl'r the :)nl tn•tdment of 54 san1ples taken h om the whole flock:- ,-l4 (.100 ]Wl' C'ent.) \\ere frpe of hookworm eggs (- ).

4:) (S0·:j per t·ent.) \\·ere free of nll l!ellllinth eggs ( - ). 4 (7·4 per cent.) \YPJP just positiw for helminth eggs (t).

8 C>··-> per r·eni.) sho,nd n light helminth infedion (tt).

2 (8·7 per l'ent.) still hntl n fair helminth infedion (ttt).

(*These samples \H're taken nt random from the 90 sheep dosed person- ally.)

409

.1.'\TJIEL~li.'\TllTC TESTS.

J•'or pnwtical puqJo~e::; lYe ean consider iltat the sheep 11·lJidt are just po:;iti,·e fm hook11·onn~ (i.e. hom 20 w JU gntuts of IYho,;e fae(·p:-; after sediJJI('Jttaliou and centrifugmg nol lllot·e than lU egg,.;

are seen iu -± to :j (hops frolll the top of t.be centrifuge liquid) are also ll(TPr1, <IS the fe11· worm:; ,,·hil'h t.hey contain 11·ould not p1odul'P

;tny dinical syni]Jtoms. \Ye ltaYe then u percentage of sheep cured of hoohYornts of 10·-J. ver t·enl. after the firs[ treatment, 82 after the second treat1nent anr1 IOU after the t.hird trPatment.; in addition \\'e find a percf'n tage t·tJrP front other hPlmint.hs of -±2 aft.Pr t hf' :;el'ond treatment a1Hl !JO·I after t.he tl1iTd trcatlllenl. Jf thPse figures, ''"hi cit sLttistic;tll_y are highly sigJJificant, are indicative of t ht>

flock, then th(• elti('acy of '-L'ehnchloretbylene, dosed imme(liatPly

;cfter the adntiJJi,.;tr;ttion or a 2 prr cPnt. solutimt of Coppl'l' sulph<ile, is >ery satisfnctor.1·. (J•'ig.) In ;1dclit io11 llw margin of safPt.\· is w r.\' high, as SOllie I ,40(1 closes 1\'l:'l'l' <Himini::;lPJ'E'cl wd,h only 7 dP;tt hs, all of ,,·hich \YPJ'e al'idental <111(1 due• to thP tlin•L:i result of the Jl<l:isagP of eillter tl1P C'oppPr sulphate solution or TetrachlorethylPne 1lirP!'t into the lungs. Jt is true thaL bloating 11·us often a sequel of dosing, hut 11-h('ll tile ,.;hf'l']l arE' tlos1'd in tliP IIJOrning·, ;Jfltor lt;n·ing ht'l'n kr:wll'tl oVE'l'lli;.dll, tlii~ l'P<tl'iion i~ not srrious: lJesi(lPs it is (louhtfnl ,,·hf'thE'r t.hi:-; hloating t·an lw l'on~illnPd to hr a g·E'JI('rnl sPquel -of 'I'PtnH·hlorethy]('IIP aclnJinistr;llion: it is possible tli;ll some ingre- tliE'nt in the fc·pfl in t.his partit·uLH <U'Pil is a prrcli~posing l'au:-;e, JWrh;tps Yf'rmE'rrhossie (G'eiqeun ~pp.) \\'bit·h is Yer~· plPntifnl in tl1iH area.

In onler that thPsE' ltighl.\· ~ignificnnt rE';;ults !'nulrl I1P confirmed or not the heatE'cl ,.;llP('jl \l'f'l'P pel'/'iOll<tll~- P:S;tminE'rl ~:) 1hys uftpr the last rlo,:;ing anll ,-10 fae(·(•s ,.;amplE's II'E'I'P ag·;1in tai;E'n fron1 differPnt shrPp.

'l'hE' imprOYPllJPnt in thE' genE'rn·l r·onclition of the treate1l E'\l'l'~ was stril;ing: "·lJE'l'P<J~ prior to hPahtJPilt tl1e.1· \I'E'J'P all Ycry thin, "·rak ancl anaPmil', theY "·erP no11· in a YC'r1· p;ootl and strong· l·onrlition.

Only three sltPPJl in thP ,,·holP filll'k ,,·prf' still poor, a11tl one of these, the onl~- one in tllP flm·k, shrnn,rl diniral ~Ymptoms of yennino~i~

(<lll<ll'll1ia ;tnrl S\l'(lllPn ja11·). 1\ post-modPm of 11iis shPt'll shm1·prl ahmli :)(1 llook,,·orJJis anrl a p;ood n1llnhrr of IYirE'\Yt>Jill.~ ;tnrl nnrh1lar

\I"OJ·JJJS. F<l!'l'(-'~ hmn t.hE' ot hPr t 11·o sltm,·f•tl no lH10b1·onn f'gg·s on f'Xalllination, hut !1oth still h;1d ;1 lig·ht inf(•l'lion 11itl1 othr·r \\'OJ'JIIS.

'l'hP ,-J() ~antplr-·.~- LikE'n at ntntlom. indurle<l far•r·ps hon1 tl1esP ihrPP shrPp, ;t111l on I'X<tlllinat ion t h1• fnllo11·ing rPsults ,,·prf' ohi<tinrrl:-

47 (04 pt>r !'Pll t.) frl'E' of hook"-m·ms (- ).

(2 Jl<-'1' l'eJil.) jnst positi,·e f.nr hoohYorms (t).

2 (4 pE'r ('ent.) b i1· infe(·tion ,,·itli hookll'()l'lll:' (ttt).

27 (--J4 per 1·eDt .) ht>P of all othPr ,,·onns (- ).

·trJ ^(:10 pE'r 1·t>nt.) ha1l ;1 n•ry li.cdli infpt·tion ,,·ith otl1E'r

\\'01'111~ (t).

4 ~8 ]Wr l'ent.) harl a lip;hi infection (tt).

:2 (4 Jlf'l' 1·t>nt.) had a fair infpt·tinn with othrr wonns (ttt).

2 (4 JlE'l' (:ent.) harl n g-ooll infE>dion 11·itl1 nthPr wonns (tttt).

410

A

H. J. ORTLEPP AND II. 0. )fONNlG-.

B

GAIGE RIA

c D

OTHER HELMINTHS

3 4 5

EXPLANATIO!<S

Clear = Free(-) Stippled- Just Positive (+) Black ~ Positive (++ to++++)

A - Before Treatment

B "" After 1st Treatment

C = 2nd D = 3rd

E ... Untreated Control Lamb$

1 = Before Treatment 2- After 1st Treatment 3 = 2nd 4 = 3rd

5 "' 25 days after 3rd Treatment

6 = Untreated Control Lam~$

Fig. 1. Columns sho"·ing worm burde~1 (Gaigeria and other Helminths) of flock before and after treatments with Tetrachlorethylene.

411