Ethod would be BlO'l'e suitable The method based on that of Plr1e

( 1946)

and involving a grov1Jootr1c estimt10n of the CO2 released from formic

acid

'by E:fICurU acetate ls apparently sat1stact(}ry 1n the presence of

other

_{fSrnEntati.on materials}

(Dr R. D.

_Batt,

_{peru .} conm.

)

,

but \\Jas

_not tested .

Succinic acid was not determ1ned quantitatively . The

best

methods available,

both

uUl1zblg

Sluec!n1c

dehydrogenase,

a.re those _{oT Krebs}

( 1 937 )

am

Rodgel� (1961 ) .

Ne! ther

of these xoothods

is

re

al

l

y

convenient for

routine analy'sls of suee1na te

as

both procedures are _very

lengthy.

- 1 20 -

4 . IMJ."\lOOlETRIC STUDIES ON R'm.mN ACTIVITY

Hungate

( 1 960, p359)

in

d1s.cUS31ng _{the microbial} ecology

of the

ruman stated : " The most difficult aspec t _{of the} ecolog­

ical amlys1s of a

habitat

1&

to obtain quantitative 1nfor.mat1on on the extent _of the .ac tivities . A complete analysis should inc lude not only a

measurement

of the total activity' but also the act1vity of ea.ch component step. The degree

of

success and completeness in an

ecological analys1s can

be

neasured

by the degree to vih1ch the

algebra.1c

sum of' the

activities

of

the

compOOOl'l,t

parts

eq.uals tbe integra too aotivi ty of the whole .

The meaauremnt of total activIty ia thus essential for a complete

analysis . For many habitats this Easur-e�nt is _{cl1fflcult� but} for the rumen 1t 1a relatively easy ."

The meaaureEnt of fe�nta.t1on aetivIty in the rumen has � applications other than that of providing ecological

information. Walter

(1952)

!3uggested that it 1s useful for

evaluating rations am studying trlC effects of antibiotic s _and

tberapeutic agents , as well as for pI.aov1ding general lnfo:mat:1on on rum1nant d1gea.t1on . The method has been used t o compare the

fe�lltation rates in

bloated

ani nornn

l cattle (H�a.te

1 955;

Fletcher and Hafez,

1 960 )

and to

study the fate of fOrmlte

(

Carrell am Hungate ..

1 955 )

and lactate in the rumen

(Jayasur1ya

and

Hungate,

1 959 )

_and the effects of antibiotic s on the rumen

- 121. -

Pour methoos have been used

for masuriDg

the a.ctivity

of the m1crob1ota . The tirst roothoo used was

tr..a t

of

:F.Brcrof't, McAna.l.ly

ar¥i

Ph1111pson

( 1 944 )

uho measured the volatile acid cc:mtent of

the

bloodstream

01'

the hoat"

am

coupled this \'J1th

the rate of flow of the blood to obta1D an estimate of

the total productiQn

of fatty

_{acids in}

the

JlIWIi'm . The secom E,thod involves .meaaurcment ot the total Ethane formed in the by ferm9ntat1on, ani 1laB

used by ll'w'lgate

(1960) .

The other t't'JO netbods

entail

_{in vitro meaSUl'Oment,s OD}

rumn contents . The zero

t.1me rate

.method of

Carroll and Hurlgate

(1954 ) involves JOOasurement of the

change

_{ill concentre.}

t10n

of

eitber substrate

or product , _{or- both, in a}

sample

01" l'IJIIlen

liquor

1ncubated :immediately _after

removal from

_the animal . The _{mnometr.1c _thod .}

first used

by

\4la.l tar

(1952)

and I4eBee

(1953)

uses the total gas

product1on

.tram 1ncubated �n contents as a. lEasUl'e of the t'otal fe.rmantat1on aet1vlty. �he zero time rate method _is 1'l1Ol"e precise tban the mnoraatric method but ia more

tim-consuming, (Hungate et al

...

196oa ) .

VaFlous methods

ha.ve

been

used to as,t1mate r'Ul'len

act1v1.ty

mno�trieaUy.

Walter:

( 1 952 )

_{,QOO Me�}

(1953)

_{both used}

standard warburg equipment capable of

measuring

the gas evolved from a.

1 -2 ml .

sample

_of

�n

l1qu.o�.. _{In view o£ the hetero­}

genous natlWe

of rumn contents# larger samples

are really requj.red . _This

was realized by

Hungate

et al.

( 1 955. 1 959.

- 1 22 -

permit the use of

larger samplos

of rwoon liquor. Their technique

utilized 1 60 _{ml . &UlOlOOtr1e vessels capable}

of holding samples

of at least 10

g . �rc'llY3 as _{used in the stan:iaJ:d Warburg}

manometers to

perm1t mea surement of the

:u.u:ag

e amount of gas produced .

Conrad

_et

( 1 958 ) used 35

_{ml. . samples} of

�n

liquor . Boda am

JQbna

( 1 962 )

used even

l.a.I*ger samples

am

measured the

gas

evolut1.on from

1 00-200

mJ. .

of

l'U.1'.En liquor .

£.float of

the methods used have

involved dilut10n of the sample witb an

inorganic

Th1z dilution of the l�n content,s. as

li'Ullgate

( 1960, 1>300)

po1nted out"

'tmod1f1es

cODlit­ ions from those

ln the

I't!Jlen,

chiefly 1n the

_{direction of} a more rapid a.n:i

longer

ual,llta1ned

aeUv1ty

Vitro, s1nee the

fe:t'nl.entat1011

products aN diluted . It The fermentatJ.on my also

be reduced because ot 1nh!b1t1on

of act1vj,ty f'oll<7N1ng

the

sudden eha.."lge

of envlr�nt

ani

_{beeau.se of the} lnh1b1

tory

effec.t

of

substances

such

aa reducing agents _{whj.ch have been added .}

lt1here _{Bubstrates have been a.dd.er! to the} rumn contents

tutier

1nvastigat1,on.

the mter1ala used nave usually been

mrltedly

d.ifi:erent .from. norwt.l

d1e� substances .

Most experiments have been carried out \fi.th

mter1nls

s:u.eh as soluble sugars" ao�uble

starcb, prepared

cellulose an-l oven-d:r1ed rorage , thus oontri­

buting £"lll�her

to t..t-w a.rt1.f1c:1allty of the system.

In the present work a matbod s1milar to those of :Boda ani

J

olma

( 1 962 )

_{and Conrad et al .}

(1953)

_{was devised}

to

cner­ coma theae IJ.m1tat1ona . Tlda sectJ.on r-e ports the results of

manometr1c

studies on the fe�ntat1on actlv1Jey

of whole ancl

- 123 -

fractiona ted rumn liquor �er varlOlW con:l1 t1ons .

0

liquor

was obtained from � ... fi5tulated

cows . _�..e aninnla were stall-fed on fresh red clover

L. ) .

red

clover

hay Ol' grass

hay,

between

8.30

am alii 4 _PI21I.

and

_were starved

overnight.

WheD the

fed

on

In document Studies on the flora and fauna of the bovine rumen : a thesis submitted for the degree of Doctor of Philosophy in the Massey University of Manawatu (Page 124-128)