THE EFFECT OF SIZE AND TYPE UPON THE EFFICIENCY OF MILK AND BEEF PRODUCTION IN CATTLE*
A. HORN, S. BOZÓ
A. DUNAYChair of Animal-Husbandry,
Research Institute for Animal Breeding, Cattle-Breeding Department, Z7nivevsity of Veterinary Science,
Rottenbille
y u. 23-25
Budapest VII Hungary
SUMMARY
Partly on the basis of their investigation and of synthetising data of the professional
literature the authors have analyzed the correlation and effects of the body size and of some
other grading characters of cattle in relation to the production of products by whole populations.
According to their examinations the efficiency of size of the individual production is not always characteristic for the trend in the productivity of the total population. Thus e.g. the selection aiming at a larger daily gain, which is advantageous for the feed conversion of the individual, may lead to the development of a cow stock of a large body weight, which may decrease the quantity of beef (calfs) and of milk which can be produced on the identic quantity
of nutrients.
Examining the relation of body size and milk-yield in populations producing under the
same environmental conditions -in contradiction with most earlier examinations— within the breed there is no conspicuous correlation between the two characters according to the more
recent results of researches. Similarly a substantial reciprocity -within the breed— between the body size of parents and beef-production of their progenies cannot be demonstrated either.
The probable cause of this is that within the breed the different live weights are not separated genetically. On the ground of all these over a certain limit no meritorious and rational increase of beef—, nor the milk production can be expected from the increase of body size.
While in relation to
milk-production
the influences of the individual cha- racters(milk quantity,
butterfat andprotein
contentsetc.)
on the individualand
population production
arerelatively clarified,
the situation is more intricate (*
) Paper presented in the Study Meeting of the European Association for Animal Production, Genetic Commission, Godollo, Ausgut 28th, 1970.
in relation to
beef-production.
The beefproduction
of cattle andparticularly
its
efficiency
is a function of a verylarge
number of characters. The selectionaiming
at theimprovement
ofgrading
characterstypical
for theindividual (daily growth
rate, feedconvention,
carcasepercentage, beef-conformation,
beef-quality, etc.)
do not enhanceunequivocally
the increase of the beefproducing capacity
of the totalpopulation.
The latter is determinedby
the maintenablecow number and
fertility
indices in the firstplace.
The selection at
milk-production
can be withgreat
difficultiesbrought
inharmony practically
with the simultaneousimprovement
of the beefproduction,
moreover the increase in the milk
yield
per cow in case ofdual-purpose breeds
does not allow alone in itself that milk— and beef
production
structures corres-ponding
to the market demands be formed.The
breeding
methodsuggested by
the authors seems useful for a simul- taneous rational increase of beefproduction
relative to milk. The mainpoint
of this is the
performance
ofutility cross-breeding
withearly maturing
beef-breed bulls in
sexually early maturing
cowpopulations
of thedairy type.
The born bulls are marketed afterfattening,
while heifers of beef breedpaternity
are fertilized at young age
-similarly
with beef bulls— and after one monthfollowing
thecalving
is marketed forslaughter
as a young cow. After thebeginning
of full rotation -with thecalving
of thebeef-purpose
heifers— the liveweight
of theproduced
young beef animal marketable after onedairy
cowgrows with 4q per cent,
against
an additionnal 14 per centstarch-equivalent
and
concomittently improves
also thequality
of the beefconsiderably.
If this starchequivalent surplus
would be allotted to beef-cattlekeeping,
the beefoutput
wouldlag considerably
behind that level which can be attainedby
the currentcalving
ofbeef-purpose heifers. Beyond
this in case ofspecial given
conditionsand
demands,
thekeeping
of beef-cattle may however likewise come into theforeground.
In the future the more extensive use of
specialised types (milk-
andbeef),
the faster breed- and
type-change
and the morewide-spread employment
ofcombinative
cross-breeding
will have to be taken into consideration more exten-sively
also in cattlebreeding.
Efficiency
ofproduction
incattle-breeding
isessentially
more intricatethan it is in
general presumed.
This is duemainly
to the fact thatefficiency
and size of the individual
production
are notalways
the same as the trend in theproductivity
of the totalpopulation.
This became evident inpoultry raising
and led e.g. to the
necessity
ofseparating
-in broilerproduction—
the maleline from the female line. The first was
put
into the service ofincreasing
the individual meatproductivity,
while the second line served the purpose of eco- nomicreproduction, utilizing
at the same time theappropriate
heterosis effect.The
diverging
interest between theintegrated
andspecialized poultry
breedershas a similar
background.
In cattlebreeding, particularly
the milk and beefproduction performed
with the samepopulation
raisessimilarly
alarge
numberof
unelucidated problems. Obviously
this resulted in thedivergences
ofopinions
being
veryconsiderable,
both in thequestion
oftype
andbody weight
and asregards
the direction ofoptimum utilisation,
even in the so-calledspecialized
breeding
aimes(specialised
beef- anddairy breeds).
This situation iscomplicated by
the need that theeconomically producing
cow must have notonly
a consi-derable
degree
ofefficiency
in order to convert the feed into butterfat and milk-protein
and toproduce economically
calvescorresponding
to the purposes offattening
but must likewise stand the test in theup-to-date
mechanised esta- blishments. Therentability
ofmilk-production
from thepoint
of view of thecow is
relatively
well reflectedby
thequantity
of milkproduced,
concentration of milk(W I TT, 6 3 ; HORN,
29;B IR 6,
4;IVICDANI!L,
49;H OFMANN , 2 8; etc.), by
themilk-yield
related to liveweight,
which seems the safest index of food conversion for thepractice (SucxAN!K, 56;
DOHY and LUDROWSYY, 17,etc.)
and evenbeyond
this
by
themilk-production
per oneday
of life related to the liveweight,
which isperhaps
the mostpregnant
indicator for theefficiency
ofmilk-production (D O II Y , 1
6).
According to
results of earlier researches(K RIZ E N EC ZKY , 3 8; G OW E N , 2 6;
TUR-N E R
, 5g; I,AUrR!cIIT
and Do RIN G, 41 )
theconception
becamewide-spread
that 100kg
increase of the cow liveweight
involves an about 300to 600kg
additional milk-production.
Thisfinding
wassubjected
to revisionby
a few research workers(JoIIANSSO N
,
37;W II ,x,
YOUNG andCOLE, 6 2 ).
From more recent examinations in which the authors studied the correlation between liveweight
and milkyield,
inpopulations
oflarge numbers, producing
under the same environmental conditions(e.g.
CLARK andTouCHBERRY,
I2; Boz6 andDUNA Y ,
7;VASILJEV
andSTARTZEV, 6I;
V
AN
V!ECK, 60;
MONOENOKV andV SJAKIH ,
5I; BREITENSTEIN andF I E DL E R ,
9;CsOmOs,
Iq.;$r,sAI!D, 23 )
the conclusion can bedrawn,
that a considerable increase in themilk-yield
of cows cannot behoped
-for from an increase of liveweight.
It seems furthermore as if the concentrated
milk-producing types
would -relatedparticularly
to a liveweight
unit— easierproduce economically.
Theoutstanding
relative
productions,
which are attainedby
concentrated milkproducing
breedsand
individuals, specially
related to the liveweight unit,
arepointing
to this fact.In this connection I may
point
to the DanishJersey,
FinnishAyrshire breeds,
as also to the cow stocks ofNew-Zealand,
etc.(Table I).
The
hungarian
results seem to confirmsimilarly
thattypes producing
amore concentrated milk
-specially
under conditions oflarge-scale farming—
can easier and with more
security
hold theirleading position,
than breeds orcrossbreed
populations producing
more but less concentrated milk.While indices of the
efficiency
of milkproduction
arerelatively
wellclarified,
thosereferring
to beefproduction
or to a combination of the two are far morecontradictory.
Thisapplies particularly
to theintegrated
beefproducing capacity
of one
population.
The cause of this is that while in somephases
offattening good
many indices orparameters
have apositive effect,
withregard
to the totalbeef
production
of thepopulation,
the effect isnegative. Already during
theCongress
atEdinbourgh
HORN( 31 )
haspresented
areport
on examinationsconcerning
the milk- and beefproduction produced by Hungarian
Flackvieh cowsbelonging
to differentweight categories,
from the same nutrientquantity.
Thedata have
clearly
shownalready
at that time that withgrowing
cow liveweight
the total beef
production
of cowcategories
from 550 to8 50 kg
comes-just
contrary
toexpectations—
into anegative phase, particularly
in relation of themore valuable young beef. On the
ground
of these and other examinations it appears that it is more thanprobable,
that the mosteconomically producing
cattletype
may befundamentally different from
that which isqualified
the bestby
thetraditional
conception.
In connection herewith it is
particularly interesting
toemphasize
thedaily growth-rate
as one of the mostimportant
individualparameters
ofbeef-production.
Thus,
e.g. a breed selectionaiming
at alarge daily gain
in the interest ofbeef production
isundoubtedly advantageous
from thepoint
of view of food conversionduring fattening.
At the same time however such abreeding
aim-specially
when
fattening
aims at alarge
finalweight—
may lead ingeneral
to heaviertypes
which mature later.The
general opinion keeps
a certainpositive
correlation in evidence between the liveweight
ofparents
and theweight gains
ofprogenies.
Parameters charac- teristic for some breedspoint
also into thisdirection,
as well as results obtainedduring
the differentcrossbreeding experiments (HORN, DurraY, Boz6,
35;S ZUR O MI , 5
8). Though
this correlation-concerning
itstendency—
is reliableby
allmeans, still a
reciprocity
within breeds between liveweight
of theparents
andweight gain
of theirprogenies
could not be established: BAR-ANAN and LEVI( 2 ),
B RINKS
et al.
( 10 ),
DUNAY( 20 ),
SZUROMI(5 7 ),
Max!ov!(q. 7 ).
This isprobably
due to the
weight-categories
notbeing sepa y ated genetically
within thedifferent
breeds. The
growing body weight
related to agiven
feedgrowing
area or to thesame feed
quantity,
diminishes the number ofproduceable
calves andcontrary
to the
expectation
reduces thebeef-producing capacity
related to the wholepopulation.
The lossresulting
herefrom may beoccasionally larger
than theprofit
which can derive from the utilization of cows oflarger
liveweight
so Nuchthe more as
according
to ourtoday’s knowledges
the mosttMt!o!M!’MM’!’Mg’/ac!
of beef production
is the numbeyof
calves which can beproduced
on thefeed-unit (Fig. I ) .
Considerations of those
shortly
outlined above led to the set ofexperiments
which we have conducted
already
hitherto and aregoing
toperform
also furtheron with the view to find out how
during
the utilization ofpopulations
of differentbody weight
andtype,
the relation andprofitability
ofbutterfat,
milkprotein
and beef
production develop
on the samequantity
of feed. A very intricatemass of facts must be
synthetized,
before certaingrades
could beassigned
tothe different
populations.
At the same time we must share theopinion
of thoseC OLE
et
al., I3 ), according
to whom for instance neither in the field ofbeef-produc-
tion do exist
unequivocally
ideal breeds. We would like topoint
out a few contra-dictions in this connection. The
capacity
of ahigh daily gain
which is a fundamen-tal character of economic
beef-production,
is in many cases manifested moresuperiorly
indairy
breeds of alarger body (e.g.
U.S.A. or CanadianHolsteins),
than is
specialised
beef-breeds(CoI,! et al.,
I3;L iNDH t, 4 6).
In the same way theearly maturity
which in the earlierperiod
offattening usually
result in a morefavourable
weight-gain
andsimultaneously
in a faster rotation of thestock, impairs
therentability
of beefproduction
in case offattening
to a heavierweight.
Neither the
fattening
to a heavierweight
is apracticable
road ofrendering
thebeef
production profitable,
since almost twice as much feed isrequired
per liveweight unit,
whenfattening
goes-on to500 -6 00 kg weight
thanquantity
neededfor
fattening
to 200-30okg weight (N A G Y ,
52;I,E NSC xow; ST UNZ , OTTO,
43,etc.).
The carcass
weight percentage
is likewiseregarded
as animportant
beef-production
index. At the same time lessdeveloped respiratory
anddigestive
organs are associated with a favourable carcass
percentage.
Thereforefrom
thepoint of
viewof
carcassweight !eycentage, exactly
thosetypes
are!ushed
into thebackground
which have thehighest feed-uptake capacity
and may be the bestconverting
animalsmainly
in relation of milk-but also of beefproduction.
Thisstatement
emphasizes similarly
thenecessity
of a certain revision of theblocky
and
short,
classical beef-cattletype, J OBST ( 3 6).
We do not wish either to deal here with the beefquality
in moredetail,
wepoint only
to the heavierweight being
ingeneral accompanied
with coarser fibres. Thus it could occur that indifferent taste and
qualification
tests(FLOCK,
zq.;E DGAR ,
21,etc.)
thebeef of precisely
those breedsproved the
best whichfro.m fattening
and meat industrialpoints of view,
obtain the lowestgrading
ingeneral. Quality
of the beef is a functionfar more of
feeding, degree
offatness,
age and stateprior
toslaughterage
ofthe
animal,
then of the breed.Considerable
importance
is attributed also to thebeef-conformation,
whichare decisive
particularly
in the selection ofsires,
ofdual-purpose breeds, though
beef-conformation is in no close correlation with either thedaily growth-rate
or with some other characters
(B A I, IK A,
I;DU M O N T,
I(!;HARING,
27;I,A N GI,ET, GRAV!RT, Ros!NIIAxN, 40 ).
At the same time the beef-conformationjudged
asfavourable and the
increasing
width-measures may lead to the tainted inheritance ofcalving
difficulties.The
shortly
outlined characters determinejointly
thebeef-producing capacity
of the individuals and their value for the meat
industry.
On the other handin relation to whole cattle
populations
thebeef-producing capacity
of a stockis determined
by
thequestion:
with which stock more milk and beef can beproduced
from the same nutrientquantity?
From suchpoint
of view several kinds ofpossibilities
areoffering themselves, commencing
from the classical dual- purpose breeds to thespecialized breeds,
in some cases with the inclusion ofutility-crossing.
In order to illustrate the effect of individual
grading characters, displayed
on
production
related topopulation,
let uspresent
five cattlepopulations, having
different individual
grading
characters used in our evaluations(Tabl. 2 ).
In our
days
one of the most seriousproblems
in cattlebreeding
ofEurope
is
undoubtedly
to create a differencial balance of milk- and beefproduction
forthe
good
of beef. This hasbiological
reasons inpart,
but national economycauses in the first
place.
Thepresently
still almostgenerally prevailing breeding tendency
sees thebreeding
ideal indual-purpose
breeds whichafter
certainpossi-
bilities are made use
off
leadslawfully
to thef ormation of f milk sur!luses
and tobeef sho y tage.
This may be traced back to a fundamentalrentability
interestof the breeder
being
linked with the increase ofmilk-yield
per cow.Having
in view that the
uptake capacity
of the milk market is limited it iscomprehensible
that an increase of
milk-yield
per cow is associated with the reduction of the cow-numbers. On the other hand this has grave consequences, since the number of calves is alimiting
factor whichbasically
is a function of cow number andfertility (HORN,
32;C ZAK 6,
15;K R6GER ,
39;B ED 6, 3 ).
This inpart
turns theattention
increasingly
to thedevelopment
of beefcattlekeeping (S CHNI TTE N , 5 4 )
and raises on the other hand the
necessity
ofbreeding
methods such as commercialcrossing, possibilities
ofinducing twin-calvings (E DW A RD S,
22;C ARM A N , II )
whichpreviously
have beenbarely
dealt withby
researchers.In our
experiments,
where weperformed
commercialcross-breeding
withHe
y e f o y
d
and Charolais bulls in a &dquo;dairy Hunga y ian
brown &dquo;population,
of50 per cent
Je y sey generatio, -beyond
the considerableimprovement
of beef-conformation and
marketability—
an about 6percent surplus appeared
alsoin
beef-production (HORN,
DUNAY,Boz6, 35 ),
whichthough regarded
initself,
isimportant,
still does notyet
solve the formation of such a ratio of milk-andbeef-production,
whichcorresponds
to the market demands.To increase the beef
production (Boz6, DUANY, DEAK, 8)
in dairy-type
stocks commercial
crossbreeding
isperformed
withHereford bulls,
extend to all heifers and to 30 per cent of the cow-stock. The born heifer of beef-bullpaternity
is fertilized at young( 14 - 15
monthsold)
age with aHe y eford
bull andafter
claving (in
about 24-25 months ofage)
followedby
one monthfattening,
the once calved young cow is marketed for
slaughterage. According
tocalculations,
related to 100 cows, with thismethod,
theoutput
of valuable young beef can be increased with about 44per cent-against
about 14per centsurplus
of starchequivalent, compared
to the result when we would not have carried out in the stock the commercialcross-breeding
and would not have made the heifers of beef-bullpaternity
to re-calfagain (Table 3 ).
This method -to which the results
published by
M!scAr,(5 0 )
and Ros-T OVZ E
V
(5 3 )
are the nearest— enables us torationally
increase the calf-numberproduceable by
thepopulation
andthrough
this the beefproduction
per onecow of the
population.
The
question
may be raised in connectionherewith,
wether it would not bemore
purposeful
to manage one-purpose beef cattle on thesurplus
feedrequired
for the
re-calving
ofbeef-purpose
heifers?According
to ourcalculations,
illustratedon
figure
2, the youngfattening-animal-live-weight production
of thepopula-
tion is less than the beef
production
realizable in the case ofre-calving
of themeat-purpose
heifers. It should be noted however ’thatIthe
beef-increaseproduceable by
means ofre-calving
thebeef-purpose
heifers cannot exceed thealready
mentioned 40 to 50percent,
therefore for a satisfaction of ahigher
claim than this the
management
of beef-cattle seemsjustified, provided adequate
conditions are
given.
This methods
provides possibilities
of an increased beefproduction
withoutaugmenting
the number of stalls in thedairy farm,
whichrequire heavy
inves- tments, so thatthrough
this therentability
of theproduction
of basic materials forfattening
can belargely improved.
It is advisable to follow thisbreeding procedure
in the firtsplace
withusing early maturing populations.
This sexualF IG
. 2. - Young beef producing ability % of cow populations of equal milk production by using different breeding methods (A population = roo %).
FiG. 2. - Capacite de produire de la viande jeune de différentes population de vaches ayant des productions laiti!res identiques (en % des performances de la population A).
early maturity
is necessary also for the reason because -in addition to thespeeding-up
of rotations—only
thus can be attained thatdevelopment, growth
of the heifer and the
building-up
of pregnancy should fall into oneperiod
andthe
building-up
of thefoetus,
from thepoint
of view ofweight gain,
should notcome into an inactive
stage.
Thorough
furtherinvestigations
arerequired
to allow the establishment of thattype
of cattle whichaccording
tospecial given conditions,
is the most pro- ductive. It should becarefully
considered that under certain conditions the female line is to beseparated
from the maleline,
notonly
in thedairy
stocksbut within beef cattle as well. In this way the
production
linked to the femalesex
(milk yield,
calfproduction, early maturity)
may takeplace
with favourableconversion,
while the characters connected withfattening (weight-gain, slaughter value)
may be ensuredthrough
the male lines. It would be advisable to liberate the minds ofprejudice
and revise ourbreed-targets
form time to time. It maybe that in
spite
of the slowgeneration
interval we must prepare ourselves in cattlebreeding
to a fastertype—
and breedchange,
in the same way which isalready
common in
plant production
but is an everyincreasingly spread phenomenon
in other branches of animal
production
as well.During
this course we shallhave to make use also of those gene reserves which have been disclosed somewhere in the world.
Jointly
with an intensivepurebreeding
at ahigh level,
this process willpush
the combinativecrossbreeding
likewise into theforeground.
Reçu pour publication en dicembre zg7o.
RÉSUMÉ
L’INFLUENCE DE LA TAILLE ET DU TYPE SUR LE RENDEMENT EN LAIT ET EN VIANDE CHEZ LES BOVINS
A partir de leurs propres recherches et de la synthèse des résultats de la littérature spé- cialisée, les auteurs ont analysé l’incidence de la taille corporelle et d’autres critères de jugement
individuel des bovins sur la production totale au niveau de la population.
Selon eux, l’efficacité ou le niveau de production individuel ne permet pas toujours de
prédire la productivité totale de l’ensemble de la population. Ainsi la sélection en vue d’une forte vitesse de croissance, avantageuse du point de vue de la transformation alimentaire chez l’individu, peut conduire à la création de souches de vaches à poids élevé, avec l’éventualité d’une décroissance des quantités de viande, de veaux ou de lait fournies pour une même quantité
d’aliment.
Si l’on examine la relation entre taille corporelle et production laitière dans des populations d’une même race, placées dans des conditions de milieu homogènes, ce qui n’était pas le cas dans la plupart des recherches antérieures, il n’apparaît pas de liaison importante entre les
deux caractères. De même, pour une race donnée, une liaison substantielle entre la taille des parents et la production de viande de leur descendance ne peut pas être mise en évidence. Cela
pourrait provenir de ce que des différences de poids vif ne traduisent pas des différences géné- tiques, à l’intérieur d’une même race. En conséquence, à partir d’une certaine limite, on ne peut pas attendre d’augmentation intéressante de la production de viande ou de lait, d’un accroissement du format.
Tandis que dans le cas de la production laitière, les productions au niveau de l’individu
et de la population dépendent de façon assez claire des caractères individuels (quantité de lait,
taux butyreux, taux de protéines, etc.) la situation est plus complexe dans le cas de la pro- duction de viande. La production de viande chez les bovins et particulièrement sa renta-
bilité est fonction de très nombreux caractères. La sélection visant à améliorer des caractères de qualité typiquement individuelle (vitesse de croissance, indice de consommation, rendement boucher et conformation, qualité de viande) n’améliore pas indubitablement la capacité globale
de production de viande au niveau de la population. Cette dernière est déterminée d’abord par le nombre de vaches et leurs qualités de reproduction.
Il est possible, sans grandes difficultés, de sélectionner en vue de la production laitière
et d’améliorer en même temps la production de viande et, d’autre part ce n’est pas à partir
de la seule augmentation du rendement laitier individuel dans les races mixtes qu’on pourra
ajuster les productions de lait et de viande aux besoins du marché.
La méthode que suggèrent les auteurs semble utile pour une augmentation simultanée de la production de lait et de viande, spécialement de cette dernière. Il s’agit principalement
de faire appel à des taureaux de race à viande, à maturité précoce, pour les croiser aux vaches de types laitier, à bonne précocité sexuelle. Les mâles croisés sont vendus après engraissement;
les génisses croisées sont inséminées très tôt avec des taureaux à viande et sont abattues comme
jeunes vaches, un mois après vêlage. Après un cycle complet, le poids vif de jeunes bovins vendus par vache laitière augmente de 44 p. 100, alors que la consommation d’unités amidon n’augmente que de 14 p. 100 et que la qualité bouchère s’améliore considérablement. Si ce surplus ali-
mentaire avait été affecté à des bovins de race à viande spécialisée, la production de viande
se situerait nettement en-dessous. Dans des conditions spéciales et selon la demande, l’intérêt de troupeaux de race à viande peut, de la même façon, apparaître au premier plan.
Dans le futur, l’amélioration des bovins nécessitera de prendre plus en considération une
plus large utilisation des races spécialisées (lait ou viande), un changement plus rapide des
races et types et un emploi plus étendu des possibilités de complémentarité offertes par le croisement.
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