O iginal
a icle
E ec
o
di e en
d ying
sys ems
o
he
conse a ion
o
oli e
lea es
on
hei
nu i i e
alue
o
uminan s
Manuel
Delgado-Pe íñez
a
And ew
Chesson
Go don
J.
P o an
Ana
Ga ido
c
Augus o
Gómez-Cab e a
"Dp o.
Ciencias
Ag o o es ales,
Uni e sidad
de
Se illa,
C a.
U e a
Km.
1,
410 13 Se illa, Spain
b
Rowe
Resea ch
Ins i u e,
Bucksbu n,
Abe deen,
AB21
9SB,
UK
!Dp o.
P oduccion
Animal,
Uni e sidad
de
Có doba,
Apdo.
3048,
14080
Có doba,
Spain
(Recei ed
I Decembe
1997;
accep ed
6
Janua y
1998)
Abs ac -Lea es
ob ained
om
oli e
ees
(Olea
eu opaea
L.)
we e
s o ed
unde
a ious
con-
di ions
o
pe iods
up
o
42
mon hs.
Du a ion
o
s o age
had
a
ma ked
e ec
on
c ude
p o ein
diges ibili y
o
lea es
when
ed
o
sheep.
P o ein
appea ed
o
be
una ailable
o
animals
ed
lea es
s o ed
o
24
mon hs
o
longe .
The
e ec
o
s o age
on
o ganic
ma e
diges ibili y
was
less
d ama ic
and due
la gely
o
he
loss
o
soluble
cell
con en s
(
=
0.97).
As
a
esul ,
he
p o-
po ion
o
wa e -insoluble
d y
ma e
and
lignin
p esen
in
lea es
inc eased
wi h
du a ion
o
s o age
while
he
p opo ion
o
wa e
o
ace one-wa e
(60:40
/ )
soluble
ma e ial
dec eased.
Despi e
being
una ailable
in
i o,
cellulase
diges ion
eleased
p o ein
om
he
wa e -insoluble
esidues
o
s o ed
lea es
in
g ea e
amoun s
han
ha
eleased
om
eshly-d ied
lea es.
I
appea s
likely
ha
p o ein
eleased
om
s o ed
lea es
was
in
he
o m
o
a complex
and
emained
una ailable
o
he
animal.
Hyd olysable
and
condensed
annins
we e
no
de ec ed
in
esh
o
d ied
lea es
and
could
no
ha e
ac ed
as
complexing
agen s.
The
seco-i idoid
glycoside
oleu opein
was
ound
in
esh
issue
(69.9
g
kg-
1)
bu
concen a ions
dec eased
on
s o age
in
pa allel
wi h
he
obse ed
dec ease
in
c ude
p o ein
diges ibili y
(
=
0.80).
(©
Else ie
/
In a)
oli e
lea es
/
diges ibili y
/
sheep
/
p o ein
/
phenolic
compounds
Résumé -
E e s
de
di é en s
modes
de
conse a ion
des
euilles
d’oli ie
su
leu
aleu
nu i i e
pou
les
uminan s.
Des
euilles
d’oli ie
(Olea
eu opaea
L)
on
é é
s ockeés
dans
di -
é en es
condi ions
du an
des
pé iodes
allan jusqu’à
42
mois.
La
du ée
du
s ockage
a
eu
d’impo -
an s
e e s
su
la
diges ibili é
chez
le
mou on
des
ma iè es
azo ées
des
euilles.
Les
ma iè es
*
Co espondence
and
ep in s.
Tel.:
34 423
3669;
ax:
34 423 2644;
e-mail:
[email p o ec ed]
azo ées
des
euilles
s ockées
pendan
24
mois
ou
plus
n’on
plus
é é
u ilisées
pa
les
animaux.
Les
e e s
du
s ockage
su
la
diges ibili é
de
la
ma iè e
o ganique
on
é é
moins
d ama iques
e
son
dus
su ou
à
la
pe e
du
con enu
cellulai e
soluble
(
=
0,97).
Il
en
a
ésul é
que
la
p opo ion
de
lignine
e
de
ma iè e
sèche
insoluble
dans
l’eau
p ésen e
dans
les
euilles
a
augmen é
a ec
la
du ée
du
s ockage,
andis
que
le
ma é iel
soluble
dans
l’eau
ou
en
mélange
(60:40
/ )
acé one-
eau
a
diminué.
Les
p o éines
des
euilles
s ockées,
quoique
non
u ilisables
in
i o,
on
é é
libé-
ées
des
ésidus
insolubles
dans
l’eau
pa
une
cellulase
en
quan i és
plus
g andes
que
celles
qui
on
é é
libé ées
des
euilles
aîches
séchées.
Il
es
p obable
que
les
p o éines
libé ées
pa
les
euilles
s ockées
on
pa ie
d’un
complexe
inu ilisable
pa
l’animal.
Les
anins
hyd olysables
e
condensés
n’on
pu
ê e
dé ec és
dans
les
euilles
aîches
ou
sèches
e
n’on
donc
pas
agi
comme
agen
complexan .
La
glycoside
seco-i idoïde
oléu opéine
a
é é
ou ée
dans
les
issus
ais
séchés
(69,9
g
kg-’)
mais
les
concen a ions
on
diminué
p opo ionellemen
a ec
le
diminu-
ion
de
la
diges ibili é
des
p o éines
(
=
0,80)
du an
le
s ockage.
(©
Else ie
/
In a)
euilles
d’oli ie
/
diges ibili é
/
mou on
/
p o éine/
composés
phénoliques
1.
INTRODUCTION
The
use
o
ee
oliage
as
eed
in
animal
p oduc ion
sys ems
is
a
common
p ac ice
in
d y
and
semi-d y
a eas.
In
he
Medi e -
anean
basin,
whe e
app oxima ely
98%
o
he
wo ld
p oduc ion
o
oli es
akes
place
[5],
he
mos
commonly
used
oliage
comes
om
oli e
ees.
T adi ional
mana-
gemen
sys ems
allowed
goa s
and
sheep
o
eely
oam
he
oli e
g o es
eeding
on
he
lea es
om
p uned
b anches.
How-
e e ,
cu en
p ac ice
a o s
ga he ing
and
bu ning
p unings
o
limi
he
sp ead
o
pa asi es
and
o
allow
ploughing
be ween
ees.
This
has
esul ed
in
a
sho age
o
uminan
eed
in
some
pa s
o
Spain
and
has
enewed
in e es in
de eloping
al e -
na i e
s a egies
o
he
u iliza ion
o oli e
by-p oduc s
in
animal
eeding
sys ems.
Any
mo e
o
collec
and
s o e
he
p un-
ings
om
oli e
ees
in ol es
d ying
he
lea es.
In
a
p elimina y
s udy,
G6mez-
Cab e a
e
al.
[8]
ound
ha
he
d y
ma e
diges ibili y
and
he
a ailabili y
o
p o-
ein
o
uminan s
ell
subs an ially
when
oli e
lea es
we e
ai -d ied
a
ambien
em-
pe a u es.
The
ex en
o
hese
losses
was
de e mined
by
he
se e i y
and
du a ion
o
he
d ying.
This
was
con a y
o
obse -
a ions
made
wi h
he
annin- ich
oak
lea es
whe e
d ying
appea ed
o
ha e
no
o
e en
a
sligh ly
bene icial
e ec
on
nu i-
i e alue
[15, 16].
I
is
well
ecognized
ha
i
empe a-
u es
exceed
abou
50 °C
du ing
he
d ying
o
eed
samples
he
appa en
lignin
and
ibe
con en s
inc ease
[27],
addi ional
ni ogen
becomes
bound
o
he
ibe
ac-
ion
[6,
7,
24]
and
diges ibili y
may
be
educed
[13].
Howe e ,
he
p oxima e
analysis
o
o en-d ied
and
ai -d ied
oli e
lea es
by
G6mez-Cab e a
e
al.
[8]
p o-
ided
li le
e idence
o such
changes
and
an
al e na i e
mechanism
esponsible
o
he
obse ed
subs an ial
all
in
c ude
p o-
ein
diges ibili y
was
equi ed.
This
led
G6mez-Cab e a
and
his
colleagues
o
sug-
ges
ha
phenolic
compounds
in
slowly
d ied lea es
may
a ec
pala abili y
and
inhibi
he
diges ion
p ocess.
The
aim
o
he
p esen
pape
was
o
examine
he
e ec
o
a
ange
o
d ying
p ocesses,
di e ing
in
du a ion,
empe a u e
and
exposu e
o
mois u e,
on
nu i i e
alue
and
o
es ab-
lish
whe he
he
many
phenolic
com-
pounds
p esen
in
oli e
lea es
(see
able
I;
[ 12])
a e
implica ed
in
he
educed
o ganic
ma e
and
p o ein
diges ibili y
o
he
d ied
lea es
when
ed
o
sheep.
2.
MATERIALS
AND
METHODS
2.1.
Collec ion
and
s o age
o
oli e
lea es
Collec ions
o
ma u e
b anches
we e
made
du ing
ou ine
p uning
o Picual
and
Hojiblanca
cul i a s
o
oli e
ees
(Olea
eu opaea
L.)
in
Feb ua y
in
1987
and
again
in
1990 and
1991.
F esh
lea es
we e
collec ed
om
he
same
ees
in
Sep embe
1992.
B anches
acqui ed
in
1987
we e
ei he
immedia ely
d ied
in
a
o ced-ai
o en
a
60-65 °C
o
16
h
and
he
lea es
hen
sepa a ed
om
b anches
by
hand
(OD
sample)
o
hey
we e
le
o
ai
d y
in
a
shed
a
ambien
empe a u e
as
p e iously
desc ibed
by
G6mez-
Cab e a
e
al.
[8].
A e
3
mon hs
he
lea es
we e
emo ed
om
ai -d ied
b anches
by
c ushing
and
manual
sepa a ion.
Samples
o
he
lea es
we e
hen
s o ed
in
sealed con ain-
e s
un il
equi ed
(sample
AD3)
o
le
unde
ambien
condi ions
o
a
u he
21
(sample
AD24)
o
39
mon hs
(sample
AD42).
B anches
cu
om
ees
in
1990
we e
ei he
baled
(0.6
x
0.4
x
0.3
m)
and
le
o
d y
in
a
shed
a
ambi-
en
empe a u e
o
9
mon hs
a e
which
ime
he
lea es
we e
manually
emo ed
(BB
sam-
ple),
o
he
lea es
and
wigs,
emo ed
mechan-
ically
om
he
b anches
immedia ely
a e
p uning,
we e
le
unbaled
o
ai -d y
and
a e
24
mon hs
(BP24)
and
42
mon hs
(MP42)
he
lea es
mechanically
sepa a ed
om
he
wigs.
Finally,
a
sample
o b anches
ha es ed
in
1991
1
was
allowed
o
become
sa u a ed
wi h
ain
wa e
be o e
s o ing
unde
d y
condi ions
in
a
shed
o
a
pe iod
o
12
mon hs
ollowed
by
he
mechanical
emo al
o
he
lea es.
Occu -
ence
o
e men a ion
was
e iden
in
his
sam-
ple
(BF).
Sepa a ed
lea
ma e ial
om
all
sam-
ples
was
s o ed
wi hou
u he
ea men
o
diges ibili y
de e mina ions
o
g ound
o
pass
a
1
mm
sc een
in
p epa a ion
o
analysis.
Two
samples,
su icien
o
analysis
only,
we e
p epa ed
om
he
esh
lea es
collec ed
in
Sep embe
1992:
one
eeze-d ied
o
p o-
duce
minimum
change
on
d ying
(sample
FD)
and
he
second,
compa able
o
he
OD
sample
p epa ed
o
diges ibili y
expe imen s,
d ied
in
a
acuum
o en
a
he
lowe
empe a u e
o
40 °C
o
144
h
o
minimize
oxida i e
dam-
age
(sample
VO).
2.2.
Diges ibili y
de e mina ions
The
diges ibili y
o
he
eigh
samples
o
oli e
lea es
p epa ed
a e
a ious
condi ions
o
s o age
we e
measu ed
using
ou
adul
Segu ena
sheep
as
desc ibed
by
G6mez-Cab -
e a
e
al.
[8].
The
amoun
o
oli e
lea o e ed
o
he
sheep
was
70
g
DM/kg
O.
75
and
150
g
o
dehulled
sun lowe
seed
meal
was
mixed
wi h
he
lea as
a
p o ein
supplemen .
The
adap a ion
pe iod
was
14
days
ollowed
by
10
days
o
collec ion
o eces.
D y
ma e ,
ash
and
c ude
p o ein
con en
o
lea es,
die s
and
collec ed
eces
we e
de e mined
ollowing
he
ecom-
mended
AOAC
me hods.
Acid
de e gen
ibe
(ADF)
and
acid
de e gen
lignin
(ADL)
we e
quan i ied
by
he
me hod
o
Robe son
and
Van
Soes
[22].
O ganic
d y
ma e
and
c ude
p o ein
diges ibili y
o
he
oli e
lea es
we e
calcula ed
by
di e ence,
aking
in o
accoun
he
measu ed
diges ibili y
o
he
sun lowe
componen
o
he
die .
2.3.
Ex ac ion
and
analysis
o
lea
samples
Samples
o
lea
ma e ial
(10
g)
we e
ex ac ed
wi h
pe oleum
e he
o
emo e
chlo ophyll
and
lipids,
ollowed
by
ex ac ion
ei he
wi h
wa e
o
1
h
a
40 °C
o
cold
ace-
one-wa e
(60:40
/ )
o e nigh .
Pe oleum-
e he
ex ac s
we e
disca ded
bu
he
ace one-
wa e
and
aqueous
ex ac s
we e
e ained,
eeze-d ied
(a e
emo al
o
any
ace one),
and
weighed.
F eeze-d ied
ex ac s
and
ex ac ed
esidues
we e
eeze -milled
unde
liquid
ni ogen
o
3
min
(Spex
6700
eeze -
mill,
Spex
Indus ies
Inc.,
Edison,
NJ,
USA)
p io
o
analysis.
To al
phenolics
we e
measu ed
using
he
ace yl
b omide
me hod
[ 17,
18]
and
exp essed
as
e ulic
acid
equi alen s
by
e e ence
o
a
s anda d
calib a ion
cu e.
Ex ac s
we e
exam-
ined
o
he
p esence
o
hyd olysable
annins
(gallo annins)
by
he
me hod
o
Inonue
and
Hage man
[ 10]
and
condensed
annins
using
he
me hod
desc ibed
o
p oan hocyanidins
by
Po e
e
al.
[21
]. Oleu opein
was
ex ac ed
om
oli e
lea es
(20
mg)
by
sonica ion
wi h
80%
e hanol
(I
mL)
con aining
0.01
mg
anisic
acid
as
in e nal
s anda d.
The
sample
was
cen-
i uged,
he
esidue
emo ed
and
wa e
(1
mL)
added
o
he
supe na an
p io
o
emo al
o
he
e hanol
unde
a
s eam
o
ni ogen.
The
sample
was
hen
applied
o
a
C18
solid
phase
ex ac ion
ca idge
(Accubond,
J.W.
Scien-
i ic,
Folsom,
USA),
which
had
been
p e-equi-
lib a ed
wi h
me hanol
(3
x
1
mL)
and
wa e
(3
x
I mL),
washed
wi h
wa e
(I
mL)
and
elu ed
wi h
50%
e hanol
(2
x
400
pL).
The
e hanol
was
pa ially
emo ed
unde
a
s eam
o
ni o-
gen
and
20
pL
o
he
p edomina ely
aqueous
sample
analyzed
by
HPLC
using
a
100
x
4.6
mm
5
p
Sphe iso b
ODS2
(Hich om
L d.,
UK)
column.
The
eluen
was
35%
me hanol
in
0.5%
ace ic
acid
a
a
low
a e
o
I mL
min-
I
and
de ec ion
was
by
UV
a
280
nm.
The
p o ein
con en
o
he
ex ac s
was
de e mined
by
he
p o ein-dye
binding
me hod
[11
using
bo ine
se um
albumin
as
s anda d,
o
as
c ude
p o ein
(N
x
6.25)
calcula ed
om
he
ni ogen
con en
de e mined
by
Kjeldahl
diges ion.
C ude
p o ein
in
he
insoluble
esidues
was
calcula ed
om
Kjeldahl
ni o-
gen
de e mina ions.
Wa e
o
wa e -ace one-
insoluble
esidues
we e
incuba ed
wi h
a
com-
me cial
cellulase
p epa a ion
(Fluka
ex
T ichode
l7
11£l
eseii)
o
24
h
a
40 °C
in
20
mM
ace a e
bu e
(pH
4.5),
and
he
d y
ma e
and
ni ogen
con en
o
non-diges ed
ma e ial
mea-
su ed
and
he
alues
ob ained
used
o
calcu-
la e
he
ex en
o cell
wall
b eakdown
and
p o-
ein
(ni ogen)
elease.
The
esul s
we e
subjec ed
o
s a is ical
ana-
lysis
using
he
PROC
MEANS
and
PROC
CORR
p ocedu es
o
he
SAS
so wa e
pack-
age
[23].
3. RESULTS
3.1.
In
i o
deg adabili y
o
s o ed
lea es
Inc easing
he
se e i y
o
du a ion
o
he
d ying
condi ions
had
a
ma ked
e ec
on
bo h
o ganic
ma e
(OMD)
and
c ude
p o ein
diges ibili y
(CPD)
in
sheep
( able
0.
Compa ison
o
he
OD
and
AD3
samples,
which
had
simila
OMD
alues
bu
di e en
CPD,
sugges ed
p o ein
diges ibili y
was
mo e
sensi i e
o
hea
han
o
du a ion
o
s o age
bu
compa i-
son
o
AD3,
AD24
and
AD42
showed
ha
bo h
ac ions
we e
a ec ed
by
s o age.
Since
he
p opo ion
o
ADF
and
ADL
p esen
in
he
lea
samples
inc eased
wi h
s o age
i
is
p obable
ha
any
dec ease
in
OMD
was
la gely
a
e lec ion
o
a
loss
ini ially
o
highly
deg adable
cell
con en s
and
la e ly
o
he
b eakdown
o
he
mo e
diges ible
cell
wall
ma e ial.
The
solubil-
i y
o
DM
in
ace one-wa e ,
shown
in
able
II,
was
consis en
wi h
his
iew
and
a
di ec
ela ionship
(
=
0.95)
was
ound
be ween
soluble
d y
ma e
and
he
OMD
de e mined
in
i o
igu e
I
Wa e
alone
was
uni e sally
less
e ec i e
han
ace-
one-wa e
in
solubilising
bo h
d y
ma -
e
and
p o ein
(da a
no
p esen ed)
al hough
he e
was
s ill
a
di ec
ela ion-
ship
be ween
OMD
and
soluble
d y
ma -
e
(
=
0.97).
The
amoun
o
p o ein
ex ac ed
by
wa e
alone
was
hal
o
less
han
he
amoun
ex ac ed
by
ace one-wa e
om
he
co esponding
sample
shown
in
able
11,
al hough
he
magni ude
o
he
di e -
ence
did
no
ob iously
ela e
o
ea men .
Di ec
measu emen
o
soluble
p o ein
by
a
dye-binding
me hod
and
es ima es
made
om
he
ni ogen
con en
(c ude
p o ein)
we e
in
good
ag eemen
o he
eeze-
d ied
and
acuum
o en
d ied
samples
bu
di e ed
in
hose
samples
exposed
o
head
o
p olonged
s o age.
In
hese
samples
he
dye-binding
me hod
ga e
lowe
alues
han
he
c ude
p o ein
de e mina ion,
pos-
sibly
implying
some
complexing
o
he
p o ein.
While
he
o al
c ude
p o ein
con-
en
a ied
depending
on
d y
ma e
con-
en
( able
0,
he
p opo ion
o
o al
p o ein
ep esen ed
by
he
ace one-wa e
insoluble
ac ion
emained
essen ially
cons an
(0.80-0.84)
in
all
bu
one
sample.
The
excep ion
was
sample
MF
which
had
been
delibe a ely
encou aged
o
e men
on
s o -
age.
In
his
sample,
he
amoun
o
solu-
ble
p o ein
was
subs an ially
highe
and
he
insoluble
p o ein
ac ion
was
(0.70)
co espondingly
educed.
The
obse ed
solubili y
o
p o ein
in
ace one-wa e
o
wa e
alone
sugges ed
ha ,
e en
i
none
o
he
insoluble
p o ein
was
po en ially
deg adable,
15-20%
o
he
o al
c ude
p o ein
should
be
a ailable
o
he
animal
and
ha
in
he
MF
ac ion
his
alue
would
be
close
o
30%.
How-
e e ,
his
was
no
suppo ed
by
he
ani-
mal
expe imen s
in
which
ew
o
he
in
i o
CPD
alues
app oached
his
igu e
and
in
he
case
o
he
MP24,
MP42
and
MF
samples,
none
o
he
p o ein
appa -
en ly
was
a ailable
( able
0,
In
appa en
con adic ion
o
he
in
i o
esul s,
in
i o
diges ion
o
he
wa e -
o
ace one-wa e -
insoluble
esidues
o
he
lea es
wi h
a
comme cial
cellulase
esul ed
in
subs an-

ial
solubilisa ion
o
bo h
d y
ma e
and
c ude
p o ein
( able
III,
esul s
o
wa e -
soluble
ex ac s
only
shown).
The
c ude
p o ein
eleased
om
s o ed
lea es
was
compa able
wi h
o
g ea e
in
amoun
han
ha
eleased
om
he
o en
(OD)
and
eeze-d ied
(FD)
samples
p epa ed
soon
a e
ha es
in
he
labo a o y.
Ex ended
s o age
(24
and
42
mon hs)
and
e men-
a ion
(MF
sample)
appea ed
o
bo h
con-
se e
and
p omo e
he
d y
ma e
and
c ude
p o ein
in
i o
deg ada ion
o
he
samples
in
ma ked
con as
o
he
esul s
obse ed
in
i o.
3.2.
An i-nu i ional
ac o s
in
oli e
lea es
Since
cell
wall
deg ading
enzymes
we e
able
o
diges
a
subs an ial
p opo ion
o
all
lea
samples
in
i o,
he
poo
diges ibili y
o
d y
ma e
and
p o ein
obse ed
o
some
samples
when
ed
o
animals
ela ed
ei he
o
he
biological
una ailabili y
o
he
eleased
ma e ial
o
o
he
di ec
inhi-
bi ion
o
he
umen
mic o lo a.
Hyd olysable
o
condensed
annins
we e
no
de ec ed
in
any
wa e
o
ace one-wa e
ex ac s
o
oli e
lea es
and
we e
dis-
coun ed
as
a
possible
an i-nu i ional
ac-
o .
The
seco-i idoid
glycoside
oleu opein
was
ound
in
subs an ial
amoun s
( able
li!
in
eeze-d ied
samples
bu
in
lowe
concen a ions
in
lea es
which
had
been
s o ed.
The
ex en
o
oleu opein
disap-
pea ance
was
ela ed
o
he
all
in
OMD
(
=
0.83)
and
o
he
educ ion
in
CPD
( = 0.80).
The
ace yl-b omide
me hod
p o ided
an
al e na i e
and
mo e
speci ic
measu e
o
lignin
con en
o
he
wa e
and
ace one-
wa e
insoluble
esidues
han
did
ADL
al hough
he e
was
a
clea
ela ionship
(
=
0.79)
be ween
he
wo
measu es.
As
would
be
expec ed,
he e
was
a
s ong
neg-
a i e
ela ionship
be ween
he
phenolic
con en
o
he
insoluble
esidues
and
amoun
o
d y
ma e
ex ac ed
by
wa e
(
=
-0.96)
o
ace one-wa e
(
=
-0.99),
mi o ing
he
ela ionship
wi h
ADL.
A
s ong
nega i e
ela ionship
( =-0.96)
was
ound
be ween
he
phenolic
con en
o
ex ac ed
lea
esidues
and
OMD
( igu e
2)
bu
he
ela ionship
wi h
CPD
was
con-
side ably
weake
and
no
signi ican
( = -0.75).
4.
DISCUSSION
T ee
lea es
used
as
an
addi ional
o
al e na i e
sou ce
o
nu ien s
in
many
opical
coun ies
o en
con ain
subs an-
ial
amoun s
o
condensed
annins.
These
ha e
been
shown
o
dep ess
pe o mance
when
ed
as
a
high
p opo ion
o
he
o al
die
o
uminan
animals.
D ying
o
such
lea es,
whe he
in
he
ield
o
in
he
labo-
a o y
does
no
appea
o
g ea ly
change
hei
annin
con en
o
nu i ional
alue
[4,
13,
14-16].
Whe e
he e
is
an
e ec
o conse a ion,
he
endency
is
o
imp o e
a he
han
dec ease
nu i i e
alue
o an-
nin- ich
lea es [ 16,
19].
The
oli e
lea es
used
in
his
s udy
we e
shown
o
be
ee
o
hyd olysable
and
con-
densed
annins.
Thei
esponse
o
d ying
mo e
closely
esembled
he
o age
sam-
ples
s udied
by
Mahyuddin
e
al.
[13].
In
pa icula ,
c ude
p o ein
diges ibili y
was
ound
o
be
ze o
in
h ee
o
he
conse ed
samples
and
much
educed
in
o he s,
implying
he
o ma ion
o
a
mo e
s able
complex
han
is
ypical
o
annin-p o ein
in e ac ions
[20]
wi h
no
pos - uminal
elease
o
p o ein.
Co ey
e
a]. 13]
wo k-
ing
wi h
escue,
Sceho ic
[24]
wi h
a
ange
o
o ages
and
G6mez-Cab e a
e
al.
[8]
wi h
oli e
lea es
ha e
all
epo ed
ha
o age
d ying
causes
a
g ea e
binding
o
ni ogen
o
he
ibe
ac ion.
Much
o
he
ni ogen
p esen
in
wa e -
and
sol en -ex ac ed
oli e
lea es
could
be
eleased
by
he
ac ion
o
a
comme cial
p epa a ion
o
cell
wall
deg ading
enzymes.
Since
a
simila elease
o
p o-
ein
would
be
expec ed
wi hin
he
umen,
he
esul ing
lack
o
a ailabili y
o
he
animal
indica es
ha
he
ni ogen,
al hough
pa ially
solubilised,
emains
complexed
in
a
o m
esis an
o
hos
o
mic obial
p o-
eoly ic
a ack.
In
he
absence
o
con-
densed
annins,
he
mos
likely
candida es
o
complex
o ma ion
wi h
p o ein
a e
o he
phenolic
compounds.
I
has
long
been
ecognized
ha
i ually
all
com-
pounds
wi h
a
phenolic
unc ionali y
can
co alen ly
link
o
sulphu -con aining
and
o he
amino
acids,
a
p ocess
aided
by
mois u e,
hea
and
ime
[25].
The
abili y
o
ace one-wa e
o
ex ac
mo e
ni ogen
om
s o ed
samples
han
wa e
alone
and
he
lowe
soluble
p o ein
es ima es
p o-
ided
by
he
dye-binding
also
a e
consis-
en
wi h
some
complexing
wi h
a
pheno-
lic
ac ion.
In
addi ion
o
lignin
in
he
cell
wall
ac ion,
oli e
lea es
and
ui
a e
cha -
ac e ized
by
a
high
concen a ion
o
oleu-
opein,
a
seco-i idoid
glycoside
which
impa s
he
bi e
as e o
he
ui
I I 11.
The
concen a ion
ound
in
he
FD
lea es
(70
g
kg-
I
d y
ma e )
ell
wi hin
he
ange
no mally
encoun e ed,
which
is
highly
a iable
and
can
each
90
g
kg-
I
d y
ma -
e
[26].
The e
was
a
conside able
all
in
oleu opein
con en
o
lea es
wi h
s o age,
he
ex en
o
which
could
be
co ela ed
wi h
he
loss
o
d y
ma e
and
CPD.
How-
e e ,
he
wo
may
no
be
causally
ela ed.
Loss
o
ex ac able
oleu opein
can
occu
because
o
hyd oly ic
b eakdown
[2,
28]
o
slow
oxida i e
polyme iza ion
[9]
wi h-
ou
any
in e ac ion
wi h
p o ein.
Poly-
me iza ion
o
oleu opein
o
i s
b eakdown
p oduc s
would
dec ease
solubili y
and
make
i
di icul
o
dis inguish
om
he
lignin
ac ion
in
any
g a ime ic
assays.
Fu he
wo k would
be
needed
o
es ablish
whe he
he
p o ein
which
appa en ly
becomes
complexed
wi h
phenolic
ma e-
ial
is
associa ed
p ima ily
wi h
lignin,
oleu opein,
o
bo h.
Howe e ,
any
sug-
ges ion
ha
oleu opein
migh
be
oxic
o
he
umen
mic o lo a
can
be
discoun ed.
The
highes
diges ibili ies
we e
eco ded
o
he
samples
wi h
he
g ea es
oleu-
opein
con en .
OMD
was
e iden ly
mo e
sensi i e
o
he
du a ion
o
s o age
han
o
hea .
Wa e
and
sol en -soluble
d y
ma e
dec eased
wi h
s o age
and
he
amoun
o
educ ion
was
s ongly
ela ed
o
he
dec ease
in
OMD.
The e
was
a
concomi an
ise
in
cell
wall
con en ,
pa icula ly
o
he
mo e
ligni ied
cell
ypes,
as
shown
by
he
inc ease
in
lignin,
whe he
measu ed
as
ADL
o
by
he
ace yl
b omide
me hod.
Howe e ,
as
indica ed
p e iously,
no
all
o
he
p opo ional
inc ease
in
lignin
may
be
due
o
he
loss
o
cell
con en s.
Com-
plexa ion
wi h
phenolics
may
also
ha e
con ibu ed
ma e ial
which
was
de ec ed
as
ADL.
O e all,
his
pa e n
o
e en s
is
consis en
wi h
he
dec ease
in
OMD
due
p incipally
o
loss
o cell
con en s
h ough
leaching
o
mic obial
ac ion
du ing
he
d ying
o
no mal
senescence
p ocesses
and
possible
wi h
he
loss
o
mo e
eadily
deg adable
cell
wall
ma e ial.
Thus
OMD
was
p incipally
de e mined
by
he
amoun
o
ma e ial
which
was
insoluble
in
wa e
o
sol en
and
i s
appa en
lignin
con en .
I
was
sugges ed
p e iously
ha
emo al
o
lea es
om
wigs
and
b anches
had
a
nega i e
e ec
on
bo h
OMD
and
CPD
[8].
Al hough
emo al
o
lea es
migh ,
in
he
sho
e m,
p omo e
au oly-
sis
and
loss
o cell
con en ,
he e
is
li le
o
sugges
ha
his
is
signi ican
in
he
longe
e m.
The
p ime
ac o
in
educing
nu i-
i e
alue
appea s
o
be
du a ion
o
s o -
age,
ollowed
by
hea ing
o
e men a ion
when
lea es
we e
exposed
o
ain all.
This
a gues
o
lea es
o
be
collec ed
d y,
s o ed
unde
co e
and
consumed
wi hin
a
3-4
mon h
pe iod.
ACKNOWLEDGMENTS
The
au ho s
acknowledge
he
awa d
o
an
EC
sho - e m
aining
and
mobili y
g an
o
M.
Delgado-Pe iez
and
he
p o ision
o
acil-
i ies
a
he
Rowe
Resea ch
Ins i u e
by
he
Sco ish
O ice
Depa men
o
Ag icul u e,
En i onmen
and
Fishe ies.
REFERENCES
[
I
]
B ad o d
M.M.,
A
apid
and
sensi i e
me hod
o
he
quan i a ion
o
mic og am
quan i ies
o