Sheep breeding

By

S.

Smith

Travees.

Eead

lltli July, 1871.

In theremarks on sheep-breedingwhichI

am

about to

sub-mit to you, I

must

beg you to understand that I do not

profess tobeable to offer you the results ofany experiments of

my

own, noraiiy theory founded on the experiments of

others.

Icannotfind, indeed,that anyexperiments haveever been

made

upon

any scientificprinciple, and

upon

such ascale as to arrive atanydefinedandcertain laws,suchas

must

underlie

and governthescience of artificial selection, whilst on refer-ence to those authorities

who

havewritten onthe subject,I

find discordancies of opinion, coupled with vagueness of

technicalphraseology, that

must

leave every one in doubt as

to whether indeed

we

do

know

scientijically

more

ofbreeding

now

than

we

didone hundredyears ago.

And

ifwhat

we

do

know

be not scientifically known,

and

proved and arranged, I

must

contend that it is notreally known, and does not really belong to us. It is true that

owingto theattention ofa very great

number

ofhighly edu-cated

men

to the subject, the most extraordinary

improve-mentsin our various breeds of sheep and cattle have been

effected.

But

ifthese distinguished breedersweretobetaken

away,where

shouM we

find, orbe able to lay

down

anyofthe

principles on which they haveproceeded? Itisvery well to

point to Mr. Bakewell,

who

in the middle of last century originated the Dishley Leicesters, and to the MacArthurs,

Learmonths, Coxes, Mr. Bailey,

and

others'to

whom

we

owe

our Australian breeds; but the questionis whatare the

principles of selection on which they have proceeded?

Had

they any?

The

reply,I suspect,would be that theprinciple, theonly

principlegoverning their selection, was to choose the finest

ram, andputittothe finest ewe or ewes, according to the

individual judgment. If

we

could ascertain the truth,

we

should find that these celebrated breeders depended entirely ontheirnaturalgifts of

hand

andeye,andupon some intuitive

sense of harmony, symmetry, and perfection which hag enabled

them

to chooseandartificially select,tillin acertain

number

of years, the same eye and

hand

and intelligence

always presiding at the drafting yard, theyhaveculminated

incertain flocks ofsurpassingexcellence.

The

question there-foreremains

—

havethesebreeders, either in

England

or

35

ascertain if, apart from tlieirindividualgenius andaims,they

obeyor seem toobey one

common

law?

The

English sheep-breeder

—

from reasons easyto

compre-hend, aims at carcase rather than wool

—

the Australian at wool rather than carcase. In these different objectsdo

we

find

them

bothadheringtoonepractice. Isthe path bywhich

each seeks to obtain perfectionbut a differentbye-

way

ofthe

one high road?

Ibelievetheanswertobe thatallintelligentbreeders pur-sue and have pursued one

common

route,though theirpaths

may

differ.

They

allbreed, or try to breed, in-and-in. Their aim

may

be for carcase or for wool;

and

again,

amongst

wool-breeders for combing or for clothing wools.

But

all experienceshows that specialityandexcellence inany

one qualityis tobe obtained only by breeding in-and-in; by

breeding like withlike.

And

thoughnot a part of

my

subject,

I

may

remark parenthetically,that withcattle andhorses the

same

generallawis accepted.

This point, the necessity of in-and-in breeding, I

am

com-pelled to assume; it would take

me

too long to bringbefore

you evidencein supportofwhat I assert,andI doubt if itbe

necessary.

But

itiscurious and illustrativeof our scientificignorance of breeding, that whilst every celebrated horse, or bull, or cow, or sheep,is invariably'the result of in-and-in breeding,

th9 wide and fixed popular prejudice is against it, and isia

favourofcross-breeding.

And

whilst every farmeror squatter,

ifhe wish to improvehis breed, will give an extravagantprice foran animal, which is the triumphant proofof

what

in-and-in breeding in certain handscanachieve,yet as arule,

you

will find he declines to breed in-and-in himself, generally

alleging thathe hastrieditandthat itdoes notpay.

At

present

what

is the practice, or

what

is I believethe

practice? Itis to confine on one station so

many

thousand

sheep of both sexes. If not to breed together absolutely

hugger-mugger fashion, yet subject to the selection of the

drafter,

who

culls and rejects all inferior specimens, to let therestbreedtogether, fathers, mothers, sons, anddaughters promiscuously, and regardlessofallshades ofafiinity.

But

Iarguethatthis isillogical. If affinity consideredin

the grosshas

worked

such

wonders—

ifthe

mere

shutting out all foreign strains of blood hasdone so

much

forbreeding

what might

notbe effected ifthe principle were carried out,

and

appliedin theminorshades scientifically?

Might

notthislaw, ifappliedscientiflcalli/, savethe expense

andtime wasted andlostin breeding the animals, whichafter

histime, the time ofthe station,

now

wastedin breeding

use-less varieties, mightbesaved, andinstead ofitstakingthirty

yearsto bring aflock ora brand to perfection it might be that ten years orloss wouldsuffice.

My

object therefore isto examine, ifIcan, this said system

of in-and-in breeding, this breeding like witli like, and by

symbolising the relations that arise amongst sheeponthose stations, where in-and-in breeding is observed, I hope to

suggest a

method

by which to classifyandarrange the various degrees of affinityintogroups, asapreparatory step towards

those experiments, whichwillI believe, if

made

by competent persons,and on a sufficient scale, enable usto lay

down

and define thelaws governing the art ofselection.

I

know

that

my

method

is crude and deficient in

many

respects, wanting in the accuracy so necessary to scientific

research. I regard it entirely asthe suggestion of an

un-scientific person to

men

more

capable,

who

may

beable to discern the truth,ifthere beany in it,and

who

in that case

may

give precision tothe symbolisation Ipropose touse.

My

proposal is toregardtheorganisation oftheindividual,

its race, its blood, or whatever is understood by these

generalisations, as a quantitative equality, and to treat it

quantitatively.

Thus

ifIcall the

ram

A, andthe eweB, I termtheproduct

oftheir union

AB

forthe male issue, and

BA

forthe female.

If I marry

A

the father with

BA

the daughter, I call

their issue A^

B

ifa

ram

lamb, and

BA^

if a ewe lamb. If,

again, Imarry

AB

theson with his mother,I callthe progeny

AB^

ifmale, and

B-A

if female. If I marrv

AB

the sonwith

BA

the daughter, I call the issue

A2

B2 if male, B2

A2

if

female.

By

this

method

I hopeto

make

thechangesin theshades of affinity apparent and tangible.

In the sketches of pedigrees appended to the paper,

and

which I

now

lay before you, I assumethat theewes produce

100per cent.,

and

an equal proportion of sexes. This for

convenience.

PedigreesNo. 1and No.4

show

thebreeding ofa

ram

with hisdaughters, grand, and great granddaughters, and if

we

examine the practice of every station where in-and-in pre-vails, itwillbefound that the resultsof this plan of

breed-ing, and the strain itproduces,

must

be theprevailingstrain,

andthe action in that direction progressively increasing in

force.

Itis truethat the stud ramsare each yearrecruited with

breeding with mothers, or of brothers with sisters, issmall

comparedto the regularandextensivemajorityofsires breed-ing each season with their female progeny.

In pedigree No. 2 youwill see the effect of four

genera-tionsbreedingback to the mother'srace.

But

to be a

toler-ablyperfect experimentyouwillremarkthat in thiscase itis necessary that the 50 ewes or 50

B

shall be wholesisters.

Inbreedingbackto the father'sline,fromthepowder the male

possesses of impregnating numbers, the relationship of his

ewes,one to the other, does not signifyto thesame extent.

Indeed, unless quite certain that they are of the highest strain, it is better

when

starting a station thatthey should not bewholesisters. For if notof the highest

known

strain

the breeder would losethe superiorchance offered byputting

60 ewes of similar but not so closely allied family, the

chance of

some

atavism in some of

them

being

awakened

andcalled outwhich should hitin with themale and produce

some

exceptional animals.

To

return to pedigree No. 2. Ifthe ewes are not whole

sisters the experiment no longer carries out its intention, as you willseeby reference topedigree No.5, where I letter

thedifferentewes

B

C

D

E

F. Turning topedigreeNo. 4, if

B

has amale lambthe experiment isonly so far perfect that I can breed

him

with his mother, andthere will be24 other

ram

lambs to breed backwith theirmothers.

The

25 ewes

that produceewe lambs areout of the experiment, andthose

ewe lambsgo to strengthen pedigree No. 1 andits effects. Imust,you perceive, breed each ewe that has a

ram lamb

with thatson, or I do not breed backtoher blood. For, if I take any one

ram

lamb, say

AB,

andbreed it next

genera-tion with all the ewes, they, not beingsisters, would merely

receive and transmit B's influence, without in the least

effectingour purpose.

AB

with hismother wouldget, itis

true,

AB2

or B^A, but with the 24 other ewes,

who

are

C

D

E F

G, the result would only be

ABC, ABD,

ABE,

ABF,

ABa.

If

AB

begets from his mothera

ram lamb

or

AB^

the next generation would be

AB^

,

AB^

D,

AB^

E, etc.

But

this is not pure line breeding back to the mother, except with one individual, andat any

moment

thattoo is liable tostop,byB's progenybeingfemale.

Again, if alltheewes aresisters,and you each generation breed

AB

and

AB^

with the original mothers, it is only

an

approximation, and

AB

breeds back only with onemother

and

49 aunts.

Ihave gone into this to prove that without extraordinary

then itis onlyan approximation. AVithold stations,

when

all the females become

more

nearly allied,the

young

rams,

when

first put in,

must

be regarded as breeding with

their aunts, and producing a sensible effect

upon

the female

progeny.

The

effectsofbreeding brothers with sisters,asinpedigrees 3

and

6,

must

again presupposealltheewes to besisters, for

ifnot sisters, vnuwill find by looking at pedigree 6 that instead of A^cbig

and

Bi6Ai<5 you get Ai^B^D'^

FG

or its equivalent; results so differentfrom thoseof pedigree No. 1

thatif tliatbe the

main

principle whichasserts itself,

and

if

thatbe the beneficialprinciple of in-and-in breeding,Idoubt

if this be also beneficial.

In pedigree No. 1you simplify

and

intensify. In

pedi-grees Nos. 3 and 6you addcontinually equal increments to

eachside, andit seemsto

me

strive to intensifythe crossing, andnot toeliminatea type.

Iam, therefore, forced to believethat pedigreeNo. 1 isthe

beneficial principle

—

not becauseI seethat itcarries outany

theory of

my

own, but becauseitis so

much

tho prevailing

and progressively prevailing eft^ectthatI conclude, if itwere

badin principle, noin-and-in breeding on the present loose

system would have beenpossiblewithoutdeterioration.

If, therefore, I

am

asked what deductions I draw from the

preceding figures, Iwould say that I

am

a believer in the

indestructildlity of type or organisation, but that I do not

believethoseoriginaltypes to have been inferiorbutsuperior to the highest specimens

now

extant. I donot believethe

original Dishley Leicester sheepto have been an awkward,

ungainly, ugly wretch, with no goodqualities of any kind.

Mr.

Bakewell, doubtless,found suchan animal, but I believe

that that was not the original type; itwas the result of

centuries

—

nay,thousandsofyears

—

ofmongrelization, ofbad

impressionsandconditions,

and

of non-observance ofthe law ofin-and-in andlike with like.

Inevery animal,I believe,acertaintyperesides,the charac-teristicsofwhich areconfused or brought out by the most

recent femaleconjunctions.

The

male blood I regardas the

indestructible organisation,and the impressionsofthe female,

whether forgoodorevil,

more

or lesstemporary.

But

Ido

not look on female blood as a thing apart. I regard her

only as therecipient, and as the conduct and channel for

othermaleblood.

When

A

marries

B

we

must

enquire

who

was B's father, for it is hisblood, andB's father's father's and mother's father'sbloodthat, if itappear, isimpressedon

with A,willclash orhit,andproduce discordantorharmonious

results.

The ram

A

in like

manner

has latent in

him

the blood not of hismother, but hismother's father.

But

this, like other maternal influence, is but temporaryin itseffect,

to be succeeded in coming generations by other temporary

female impressions, tbe blood he hands

down

permanently

being his father's father's father's

and

great-grandfather's

blood.

To

givethe question a

human

significance,Ibelieve thata

man

hands

down

to his sons his father's influence, modified temporarilybyhismaternal male blood

and

his wife'smale

blood

—

to be modifiedin their turn by their mother's male

bloodandtheir wife's.

InallthepedigreesIhave

made

out Ihave onlytreatedof

one

ram

with 50 ewes.

To

examinethe subject in the proper

manner, by thehypothesis ofa

number

oframsputtoalarger

number

of ewes, would have

made

ittoo complicatedfor

my

purpose. It suffices to point out thatin duecourse the

rams

become bythe action of pedigree No. 1 brothers and

half-brothers,

and

that thoughtheir action is only in a certain

number

of cases direct, that is to say, that of

own

great-grandfatherto

own

great-grand-daughter, yet if not direct, it is indirectlyso, andthat ittends tobecomethat of grand andgreat -grand-uncle withtheirgrandandgreat-grand-nieces.

The

wholetendencyofin-and-in-breedingwithsheep,owing tothepower of one

ram

toimpregnate 50 females, is

more

and

more

to intensify

and

revert toA'stype.

If these are the tendencies of in-and-in-sheep-breediug, cannot the desired object be attained

more

effectually

and

40

PEDIGREE

No.

1, Or, liuu-brccdingl)ackto Siic.

a= 506

25 ab 'loba

2ndGeneration.

a

=

25ba VI(Cb 12ba''

3rd Generation.

a

-

liba'

C a'b Cb a-4th Generation.

a

=

Cyba'

Sa'b

3b a'

PEDIGREE

No.

3,

Or,Progeny

mth

Progeny.

«

=

50& (allwhole

, ' , [sisters).

25a6 26ba

2ndGeneration.

ah —

26ba

12 a'b'' \2b'

3rdGeneration.

a^b^

=

12V~a" 6a'b' 6b'

4th Generation.

3a'^ b'' 3b''a'«

IfPedigreeKo.1beaninstanceof

in-and-in breeding, this is not. And yet thesetwosystems, soutterly opposedin principle,come underthepresent nomen-clatureof" in-and-in breeding"!

PEDIGREE

No.

2,

Or,line-broeiling IjacktoMaternal

line.

a

=

50b(allwhole

f

' _[sisters.)

25ab 25ba

2nd Generation.

ab = 50b

25ab' 25b'a

3rd Generation. ab- = 50b

25ab' 26b'

4th Generation. ab'

=

50/>

25a6^ 25//a

PEDIGREE

No.

4, Fathers with Daughters,

Or, No. 1re-stated (the Ewesnot beingSisters).

Tosavetrouble,thoseonlyaretakenwho

aresupposed tohave femaleoffspring

exceptinthelast, whereba^ has a ram-lamb.

a=6 a—c a

=

d

a=e

U

U

k

k

ba ca

da

ea

2ndGeneration.

a

=

ha a= ca a

= da

a=e.a

L

k

i. i.

ba^ ca^ da^ ea^ 3rd Generation.

a=h

a^ a=ca'^

a=da^

a

=

ea?

i.

_U

L

_L

ha^ ca^ da^ ea^ 4th Generation.

a

—

ba^ a=ca^a

=

da^ a—ea^

a*6 ca"^ da* ea*

Thefactofthe ewes not beingsistersdoes notaffect theresult whichis, tobreed

41

PEDIGREE

No.

5, Line-breedingbackto Maternal-line (the Ewes

not beingSisters); andisNo. 2re-stated.

a=h

a=c

a—d

a=e

a—f

a ca

ad

ea af

2iidGeneration.

ah

=

b ah =c ah

—

d ah

—

e a'b-f

I

J

I

II

V^a ahc

dab

abe

fab

3rdGeneration.

abc—b

abc=c

abc—d

abc^e

abc=f

J

I t

r

J

ab"c c^ab

abed

eabc abcf

4th Generation.

abcd-b abcd

=

c

abcd=d

abcd

=

e

abcd=f

b'^acd abc^d d^abc abode fabcd

Inthisschemeisshewnhowimpossibleitseemsto in-tensifythe mother's blood, unless all the mothers are wholesisters.

—

Notbeingsisters,and assumingthatyou musteach generation take ayoung ramfromadifferent

mother,whichvirtuallymustbe thecase,asyoucannot suppose oneewealwaystoproduceram-lambs,nor,ifshe

did, canyousuppose themalways fitted forthe stud.

Suppose, however,this tobe thecase,andthatthe eweh

hada grandsonby herson,anda great-grandsonbyher grandson, thenitwould showthuswith the other ewes:—

2nd

Generation.

ab

=

b ab

=

c ab

—

d ab

—

e

ab—f

I I I I I

ab'^ cab dab eab fab

3rd Generation.

ab'=b ab'^c ab'

=

d ab'

=

e ab'^f

a6' cab' dab' eab' fab^

4th Generation.

ab^-b ab^=c ab^=^d ab^

=

e ab^=f

a6* cab^

daV

eab' fab'

Eitherallthe ewesmustbesisters,oryou mustfindaewd

OrNo. 3 re-sttatcil.

Or, half-Brotliers, half-Sistcrs andCousins; tlicoriginal Ewes nnt' beingSisters.

Tosavefiguresandtrouble, the ewesaresupposerlto givefemalelambs,—saveand exceptone ineach generation, from which Itaketheramtocarryonwith;his

maternityIvary eachgeneration.

a

=

h a

=

c a=d a=e a

_—f

(f~(J

a=k

^\

II

I

C

C

'-^

ah ca

da

ea

fa

ga

ha

2nd Generation.

ab=ca

ab=da

ab=ea

ab=fa

ah=ga

ab=ha

I

J

'

'^^

L,

Q

ca^b a-bd ea^b fa'b ga^h ha'b

3rd Generation.

a'^bd=ca'^b

II

a'^bd=ea^b a"bd=fa-h a'^bd=ga'^h a'^bd=ha-b

I I l,_^

h'a*cd b'a'ed a'b^df b'a'gd h'a*hd

4th Generation.

a*b'd/=b'a*cd

k

=h'a'cd &,=b^a'gd

&

=b'a*_hd

k

'-.

^

^