NST I -Fur sENEGALAI s DE RECHER CHES ...
1 NST I -Fur sENEGALAI s DE RECHER CHES
DEPARTEMENT DE RECHERCHES
AGRICOLE (I.S.R.A.)
SUR LES PRODKTI ONS
-..-----e----------
ET LA SANTE ANIMALES
LABoRATO I RE’ NATIONAL DE L’ELEVAGE
ET DE RECHERCHES VETERI NA I RES
DAKAR-HANN
< *
.
CEREAL STRAWS IN THE FEEDIN6
SYSTEM OF RU+IINANTS IN SENEGAL
S . F A L L , H . G U E R I N , C . S A L L a n d N D . MBAYE
,-
t-
R E F , N“ 69/AL. N U T .
’
I
SEPTEMBRE 1987
1
i
l
PAPER PRESENTED AT THE qTH ARNAB WORKSHOP/ANNUAL
GENERAL MEETING 19-23m OCTOBER 1987, b’4MENDA
- CAMERQUN
INTRODUCTION
A moving back of drought has been recorded in African sahelian countries
durfng the two pas-t years. Thus, pastures are in better condition, however the
availabie biomass remains insufficient. Alimentation is still the major
constraint to the improvement of livestock productiv i ty in Senega .
The challenge for research workers Iivestock technicians an d fat-mers
is to imagine a highly efficient feeding system using the available feed
ressources in'each region of Senegal.
Within the framework of agriculture and livestock association, low
quality trop residues emerge as one of feed ressources wich would play an
important role in the attempt of meeting dry matter and emergy requirements of
ruminants in senegalese agricuitural.
In 1986, 887 820 tons of maize, millet, sorghun and rice grain have bean
harvested. The estimated straw out put is 4 800 000 tons (FALL et al. 1987). This
aval table quantity is expected to Increase soon with the development of irri-
gation in senegal river valley. The main areas of production are the groundnut
basin, senegal river valley, Tambacounda and Casamance.
Prevlous studfes carried ou-t in LNERV have emphasized the low concentrs-
tion In digestible nutrient bulkiness and low Ingestibility of cereal straws
(CALVET et al. 1973, CALVET et Al. 1974, SALL, 1985, FALL et Al. 19871.
. . /. .*,
TABLE 1 : CEREAL STRAW SUPPLEMENTATION
I
I
1RATlONS
SPECIES
N&lBER
LEVEL BF
OF TRIALS
'-"'TF#TE
?A
Rice straw + Cotton seed
Sheep
7
26
Rice straw + Peanutt cake
1 1
7
10
Il
1 1
Cattle
2
615
!I
11
11
8
10
11
3
15
Rice straw + Rice poiishing
11
12
22
17
?V
Sheep
2
45
Rice straw + Rice break
1t
4
28,5
Rice straw + molasse + urea
t1
2
21,5
Rice straw + P*
Cattle
6
20
PJC = mixture w/w of rice polishing and maize bran
-3-
TABLE 2 : CHEMICAL VALUE OF AGRO INDUSTRIAL B'f PRODUCTS USED AS SUPPLEMENT
-
-
-%.
AGRO-INDUSTRIAL
Cotton
Peanutt
Mixture w/w
Rice
Rice
cake
Rice poiishing
seed*
+ Maize bran
polishing
break
N = 13
N"z 1
N = 14
N=6
-L-
Ash
41
52 k 5
103
63 2 3
153 + 7
Protein
193
504 2 50
135
119 ?- 53
81 Is: 0
Crude flber
250
28 2 9
78
65 + 30
70 * 1
Ether extract
184
7co
76
44 k 32
16 -: C
Nitrogen free extract
256
408 + 24
608
568 + 242
683 + 10
Calcium
1,5
1 J
191
0,8 rk 1.2
1,2
Phosphorus
5,l
6,2
935
10,7 + 0,o
* mean value indlcated by MONGODIN et TACHER 1979
-4-
Offered alone,
cereal straws cannot meet the maintenance requirement of
cattle, sheep or goat. They need to be associated with concentrates in order
to support intensive or seml
intensive milk or meat production. Chemical treatment
cari also improve ingestibility and digestibility of I ow quality roughages.
Supplementation and alkali treatment of cereal straw have been carricd
out in LNERV and IEMVT. The objectives of this paper is to describe experimental
procedures, discuss availablc results in order i-o set up a best way of into
gratlng cereal straws in the senegalese feeding system of ruminant.
EXPERIMENTAL PROCEDURES
Supplementation of rice straw
The main objectives of rice straw supp tementa-t ,ion was to improve rumen
environnement and increase straw digestibility. Rations were intended to allow
either maintenance or milk or meat semi intensive or intensive production.
Thus rice straw has been associated to agro-industrial by produc-tsdescribed in
table 2. Composition of rations species and number of tri.aIs are specified in
table 1.
Alkali treatment of cereal straws
NaOH and urea treatments of cereal straw have been comparatively carried
out.
TO avoid unjustifiable excessive
loss of water a semi humid method (JACKSON 1979)
has been applied.
Different levels of urea (3,5 and 6 p0 100) and sodium hydroxide (3, 4, 5
and 6 p. 100) have been tested.
The effect of urea treatment in dffferent species of cereal straw, millet,
sorghun, maize and rice, has been reviewed,
. . . / .*.
-5-
Evaluation of rations nutritive value
The nutritive value of supplemented rice straw, and alkali treated cereal
straws has been evaiuated by chemlcai analysis and in vivo digestibi iity -i-riais.
Chemical analysis Involved, organic ma-t-ter, crude fiber, crude protein,
NDF, ADF, lignin, silica and minerals.
In vivo digestibilitles have been carried ou-t with a lot of six cattle
or sheep. This experiment was brcken down into tow phases. 15 days of adJustment
and 6 of measurment.
-6-
TABLE 3 : SUPPLEMENTED RICE STRAW : CHEMICAL VALUE AND DIGESTIBILITY OF RATICNS
-
-
-
-
Rice straw Rice straw Rico straw Rice stral
+ cotton
+ Peanutt
i. Peanutt
+ Peanut 1
Rice straw
seed
cake
cake
cake
i
500 g/dsy
1 kg/day
250 ç/day
ANALYSIS
i
CATTLE
. SHEEP
SHEEP
CATTLE
CATTLE
CATLLE I
ût-ganic matter
j827?19}
-
824 +- 25
833 f 9
836 t: 1
840
-
N=29
-
N=7
N =8
N=3
N ~2
1.
Crude protein
25$r13
_
89 f 12
67 + 8
105 iY 1
49
N = 29
N=7
N=8
N=3
N=i?.
3
_I---
Crude fiber
360 C 34
335 24
f.
334 f 10
320 rt 6
325
N=29
-
N=7
N - 8
N=3
N=L
--.
"Ether extract
14 2 4
53 $r 10
11 I!I 4
13 t 3
l--0---- -4
/
N =29
-
N =7
N=8
N=3
H=Z
(
Free nitrogen exi-ract
428 -e 19
-
381 & 29
422
397410
456
-
-
-%-?3
N=29
N=7
N=8
N=3
--'
1
N = 2
WV.-
-
-
NDF*
555
503 2 42
N=l
-
N =6
t
- - 3
ADF*
428
-
497 i: 46
.*
N=2
N=6
o--e
Lignin*
62
-
75 f 10
- -
N-2
N - 6
-“-
*/
.-- -.--
Silica*
Calcium*
la9
2,4t 0.8
1.8 1- 0.4
1.6 k 0.0
f3-37-/
N -2
N=7
N .= 13
N=3
N = 2
--.. .-. --..
Phosphorus*
0.7
1.9+ 0.6
1.1 + 0.1
1.6 c 0.0
0.9t 0.0
-N=2
N=7
_ N - 8
N=3
N=2
_._ ,_._ -. . ..-
-
-
-
Magnesium *
-.
_
/I
--.--
Potassium*
-.^--_
C0gdt ppm
0.5 =
-
t
N 1
Cuivre ppm
5 . 8
=_/
N=l
-
-
-
-
- - - -
Zinc ppm
.-
43.1
- - - -
N =l
-.
Manganèse ppm
623
-
N =l
.--... -..-. _.
? Iran ppm
1186
. .
mm
-.
N =l
_---- -
Sodïum ppm
_.
.
Dry mai-ter dibstibifi-
562 5
49 k 3
502 4
54 -r- 3
57
___-.-- 63
ty qp. 100)
N = 15
N = 15
N=7
N >e fj
N =3
N=2
Organic matter digesti-
642 4
58 +4
57-L 4
63 1- 3
64
-----.-- 69
2ili-ty (p. 100)
N = 15
N = i5
N=7
N
Digestible organic
39+ 7
2% 4
28+ 2
49 =8
-: 6
N =3
N=2
_--._-
y
:~~
-*
matter intake
N = 15
N = 15
N=7
Il N=8
Digestible crude
3-+ 4
ot 13
45+ 10
35 2 9
76
34-‘-
protein
N = 15
N = 15
N=7
N = 9
M - 3
N = 3
Voluntary Intake
7411 9
485 7
60+ 4
95 15
t
100
101
--
g/ky p 0 75
,N ,
=15 N
=15
,
N=7
,N=8
N=3.
Iv=2._---
4. - li.- fi..
-7-
TABLE 3 : SUPPLEMENTED RICE STRAW : CHEMICAL VALUE
AND DIGESTIBILITY OF RATIONS
RATIONS
Rica straw Rlce straw Rice straw Urea greatec Urea greated
+ Peanutt
+ Rlce
+ rice
Rice straw Rice straw
Rlce straw
cake
pollshing
break
+ Urea
+ Molasses
+ rlce polishing
10 p 100 + maize
+ Urea
bran
ANALYS l
S
CATTLE
SHEEP
SHEEP
CATTLE
SHEEP
SHEEP
SHEEP
Organic matter*
049 Y? 19
793
841 c 2
838 k 5
a03 818
N = 14
N - 2
N - b
N =6
N = 1
N - 2
Crude protein*
63’ 1 1
147
52r 2
47 Yk 2
141 73
N = 14
N=2
' N-b
N - 6
N = 1
N = 2'
"rude fiber
2 6 0 f 3 5
258
255 + 6
242 - 8
369
344
N = 14
N=2
N = b
N - b
N = 1
N = 2
1 Ether extractr
312 = 22
17
29' 2
12 i 0
17 10
N
14
N = 2
N = b
N=6
N =
1 N 2
fiitrogen free extract
495k 16
371
505+ 4
583 k 3
356
SOL
N = 14
N.2
N=6
N =b
N = 1
N:i
N D F”
413
499
N=2
N - 2
A D F*
229
324
N=Z
N=2
Lingnine*
4 6
4 9
N=2
N - 2
Silica*
100* 9
15
1.6' 0.1
3.3 2.1
N - 6
N=2
N -6
N =
1 N-2
CaIclum*
2.0+ 0.4
3
1.7' 0.1
0.5 2.3
N = 14
N=Z
N = b
N =l
N=2
Phosphore*
4.0' 1,7
2.5
2.4+ 0;4
N = b
N - 2
N.6
Magnesium*
3.2? 0,6
2.2
N - b
N - 2
Potassium*
11.72 4.1
14.9
N=6
N=2
;y--j
Cobalt ppm*
0.6
0.5
N = 2
N=2
Cuivre
9.1
7.5
----J----
ppm
N=2
N = 2
-I
Zinc
43.8
47.3
.- ------- ++
ppm
N = 2
N=2
Manganèse ppm
5880
5600
N=2
N = l
Fer ppm
9 6 7
1103
N = 2
N =l
Sodium ppm
1938
N = 1
59i b
47
47
c
Dry matter digestibility
75+ 2
501t 4
46 50
,oo 1
N - 1 3
N = 2
N = 2
N =b
N -6
N i 1
=
N 2
Or;ga;FoJmattnr
dlgestihility
7c' = +3
55
57 =
79+ 1
58 f 3
P
N 13
N = 2
N
2
N=6
=
/
N56
5g
N
6
,
=
N 2
v
Digestible organlc matter
6 4 k19
intake*
N =
95+ 15
33 te 4
13
N -6
N ): 6
,
;I
Digestible crude protein
42 '7
43
107
332 1
loi 3
N = 13
N - 2
N=2
N=6
N;b
Voluntary intake
102 ? 22
6 5
g/kg p 0,75
53
N = 13
N = 2
N=2
137 = + 21
69 = +5
N 6
N 6
* g/kg DM
TABLE 4 : DIGESTIBILITY OF RICE STRAW IN COMPOSED DIETS COMPARED TO RICE
STRAW OFFERED ALONE
l-
--
R A T I O N S
SPECIES
ORGANIC MATTER
DIGESTIBILITY p 100
Rice straw
N =15
Cat-tle
645
4
Rice straw
N =15
Sheep
58-
4
+ Peanutt cake 500 g/day
N=8
Ce-t-t-le
59.62
2,7
19
1 kg/day
N= 3
Il
59.3+
2.0
fi
250 g/day
N=2
Sl
68.4&
0.6
+ Rice polishing
+ maize bran
N =6
II
80.9+
1.5
II
+ Rice polishing
N =12
73.8t
4.4
II
+ Rice break
N=6
Sheep
37.12
5.7
i
J
-9-
RESULTS AND DISCUSSIONS
I - RI CE STRAW SUPPLEMENTAI ION
1 .l - Peanutt cake
-
Peanutt cake is avai lable in the whole groundnut basin and in the
south of LSenegal .
Rations based on rice straw plus peanutt cake have been wel I consumed
(sec t a b l e 3).
TO improve digestibi lity of straw, the levei of peannutt cake should be
restricted. Previous studies (CALVET et AI. 1980, MBAYE et AI. 1983) have
shown the depressive effect of peanutt cake on organic matter digesti bi lity
(@ID) of straw when used in a too high percentage. Table 4 shows a significant
(P 50,051 depression of rice straw OMD at the level of 500 peanutt cake per
day (10 per cent).
Cuviously the improvement of rice straw OMD has not been
significant at the level of 250 g of peanutt cake pet- day. The same for the
rice straw @ID depression at 1 kg peanutt cake/day.
In conclusion, peanutt cake raises the nitrogen, energy and phosphorus
levels of rations based on rice straw the limitation of this concentra-t-e to
10 per cent of the diet and use of urea for nitrogen deficiency could allow semi
intensive meat production (sec tables
5 and 6)
1.2 - Coi-ton seed
Cotton seed cari be associated wfth tice straw in l-h2 south Senegal
(Casamance and Tambacounda 1. This concentrate represented 26 p 100 of the
ration based on rice straw.
/
.,,
..e
-lO-
Table 6
suggests an addition of urea to reach the semi intensive beef production
al lowed by energy level of the ration
1.3 - Rice agro indus-triai by products
Rice break, polishing an bran represent great feed ressource potential
avai lable in the aeria of rice production.
Used atone or in association (w/w) with maize bran, rlce polishing gives
an adequate supplementatlon of rice straw and improvod significantly (P ZG 0,05)
its OMD (Table 41.
In both cases the ration has been rich in energy and could support intensive
fattening of cattleWltha nitrogen source such as urea were added (Table 61
Rice break is rich in starch. It represented 28 per cent of the ration. Thic,
level has been too high and could explain the significant (F < 0,051 dépression
of rice straw OMD. This by-product should be reserved toputtry ,.
1.4 - Urea and mol asses
It is wel I documented that urea is a cheap nitrogen source able to
improve intake and OMD of low qua1 ity roughage.
Wi thout a goad energetic source, ruminant use of urea is poor.
In Senegal, molasses and rice straw are avai lable in the same aeria
(Senegal r i v e v a l ley). Jhe arsociatlon of rice straw, molasses and urea (20 p 100)
gives a mixture wel I consumed by ruminants. An addition of peanutt cake and
minerais could allow intensive or semi intensive beef fattening.
. . /
. l . .
i
TAELt
5 f JjUTRITIVE VALUE OF P?TIOffS BASE0 ON RICE STRAW _
I
l- INGESTIBILITY
ENERGY
T-
1
PFXITEIN
T Ml NERALS
--
NUMBER
RAT 10 NS
SPEC'ES OF TRIALS
g/lOO kg 9/k9
DMA
DCP
Calcium
hosphor
BW
p 0,75
-jig-zT p 100
3/kg DM
g/kg DM
9h
-.
-
-
RS*
CATTLE
15
1872 +209
74 c9
64 k4
0.5+ 0.0
-19.0
324
1 l 9
0.7
te
SHEEP
15
2053 *253
48 7-7
58 +4
0.e 0.0
-11.5
0 1: 13
RS + Cotton seed
tt
7
2545 -162
60 +4
57 +4
0.5+ 0.0
50 26.1
45 -t 10
2.4 +O,ô
1.92
I
RS ) Peanutt cake 500 g/day
CATTLE
a
2365 2355
95 +15
63 $13
0.41t 0.0 53.8.117..7
35 t 9
1.8 +0.4
1.110
RS + Peanutt cake 1 kg/day
II
3
,504 +52
100
64
0.52 0.0 72.8 +1.2
76
1 .6
1.6
RS + Peanutt cake 250 g/day
If
2
3485 $16
101
69
0.6& 0.0 44.8
34
2.3
0.9
R; + Rice poiishing
13
2599 5435
lC2 fL2
74 ?3
0.72 0.0 66.6 k1O.C
42 '7
2.0 20.4
4.02
'iS + Rice polishing
SHEEP
2
2890 295
65
55
0.5+ 0.1
._
43
-.
RS + Peanutt cake 10 p 100
??
2
2290 2143
53
57
0.3' 0.1 73.2
107
3
2.5
R; + Rice polishing + maize
bran
I
CATTLE
3351 +373
137 s21
79 +1
0.8+- 0.0 64.3 k3.1
33 +1
1.7 +0.1
2.42
RS * Rice break
11
3007 -1157
69 5
58 f3
~
0,4+ 0.0 21.3 26.2
10 +3
/
SHEEP
1695
40
56
0.4
74-ç
106
0.5
I
FI
2626 +559
61
59
0.45 0.1 43.5
32
2.3
-
-
*RS = Rice straw
<I
c
c
1
N9
TABLE 6
: LEVEL OF PRODUCTION ALLOWEO FOR UBT BY RATIONS BASED ON RICE STRAW
T
LEVEL OF
PRODUCT I ON
R A T I O N S
SPECI ES
EN ERGY
DIGESTIBLE
M I N E R A L S
CRUDE PROTE I N
T CA LC I ‘UM I PHOS PHORUS
RS
CATTLE
qaintenance+lOOg/day
: mai ntenance
mai ntenance
< mai ntenance
Tic
SHEEP
: Mai ntenance
c m3 i ntenance
- -
RS + Cc-t-ton seed 26 p 100
?9
lai ntenance+300g/day
IÛ i ntenance+ 100 g/dal r Flaintenance+lOO g/day Mai ntenanco+lO
TIS + Peanutt cake 500 g/day
CATT LE
99
+250g/day
Maintenance
Maintenance
< mal ntenance
I
i.S
11
1 kg/day
!t
99
+300g/day
!l
+750g/day
< mai ntenance
Mai ntenance+ 101
iS
IY
250g/day
il
9;
+500g/day
Mai nt enance
F!a1 ntenance+ 1 OOg/day
( mai ntenance
RS + Rlce poiishing 22 p 100
”
S?
+l kg/day
4ai ntenance+ 90g/day
mai ntesance
1 mai ntenance
RS + Rice polishing 45 p 100 SHEEP
99
+500g/day
99
+250g/dsy
RS + Peanutt cake 16 p 100
l?
: maintenance
91
+ l kg/day
vlai ntenence+25Og/day
Mai ntenance+501
RS + Rice polishing+ maize
bran 20 p 100
CATT LE
>Mai n-tenance+l kg/day
tt
+1 OOg/day
vlai ntenance
Maintenance+501
RS + Rice break 28.5 p 100
Mai ntenance+300g/da
< mai Ttenante
‘Jrea processed rice straw
SHEEP
+ urea 1.5 p 100
: Maintenance
4ai ntenance+560g/day
< mai ntenance
RS t (molasses + Urea )2oploo SHEEp
4oi ntenance+l OOg/day
Mai ntenance
-
.
>
TABLE 7 : UREA TREATMENT OF CEREAL STRA\\Y’
COMPARISIGN OF RICE, MI LLET, MAIZE, AND SORGI-UM STRAWS
-
-
M S V I g sec/kg (p 0,7!
Rice s t r a w
57.2 k 4.8
5 2 . 6 t 10.3
n - 6
Mai ze straw
. ..---
Cont ro 1
3 . 9
4 9 . 3
5 2”4
3 9 . 5 +
4 . 6
n = 1
n =6
n =6 - -
Processed
14.10
5 8 . 8
t 5.5
5 6 . 1 +-
3 . 4
n = 1
n = 4
n - 4
1
F?i I l e t s t r a w
Contro l
a.4
39.2
5 6.4
3 1 . 5 -
6 . 8
n = 1
n=5
n =4
e-e-
Processed
14.60
65.1
f 2.7
68 .4 i
3 . 4
n = 1
n =6
n =6
Sorghum stra#
;
ControI
1 4 . 2
n ~ ,
1
47.2
* n4z72
Iv 49.8 k
6 . 2
n
=
5
.
*
-14-
TABLE 8 : EFFECT OF UREA CONCENTRATION ON DRY MATTER DIGESTIBILITY AND
INTAKE OF PROCESSED CEREA4STRAWS .
I
UREA CONCENTRATION
DRY MATTER
DRY MATTER
CEREALS
p 100
DIGESTIBILITY
INTAKE
p 100
g/kg p. 0,75
L
w/w mixture
1
I
millet straw
3
42.4 4 1.1
N=4 3027
N=4
+ malze straw
5
56.0 k 8.4
N = 4 41 2 14
N =4
+ Sorghum straw
6
50.0 k 6.0
N=3 3425
N=3
TABLE 9 : DRY MATTER DIGESTIBILITY OF MILLET STRAW TREATED WITH Na OH
-
-
l
Na OH
CONCENTRATION
INCUBATION TiME'
30
40
50
60
24 hours
52.6
56.1
58.6
62.5
-"
48 hours
52.4
57.6
57,2
62.6
I
96 heurs
5202
56.4
57-9
62.8
1
Control = 36 p 100
From L.N.E.R.V. 1977 annual report
Q
Tl
-. - -.
0 OJ
L-l -l-i- 2iT- 3’
D Y
3 -l- 0’ -
N
%
. ul
PS ul
b CO
P m
-
$2
-.
P
-.
u3
P
-.
a
-
P
-.
0
w w
P
-.
r-3
.p
.s
-.
-
.b
-.
NNNN-NP
P
-*
-
CD
P
a.
o\\
-N-.lcl*--.lwEi:UI
0 0 N N
P 2
-.
w
P ‘&
~
N w N -4
a
$2.
S313S~ZXL~~~
d
------------
N
,w
-16-
I I - ALKALi TREATMENT OF CEREAL STRAW.
2.1 .- Urea treatment of cereal straw
Intake, digestibility and nitrogen concentration have been improved
by urea treatment of rice, millet , sorghum and maize straw (sec table 71,
Rice straw cannot be compared to otheîs roughages because it has been
sundried. Mai, e , millet and sorghun straw have been offerad humid. The nitrogen
levcl of rice straw has been under estimated.
Compared t-o maizo and sorghum straws, millet straw gave a superior improvi-
ment of intake and digcstibility whil e the first had a highcr capacity of nitt-e--
gen fixation.
Tho results in table 8 describe the effect of urea concentration on coreal
straw
mprovement . 5 p 100 has been the optimal lovel.
2 - Na OH troatment of millet straw
Avaflable results show a positive influence of Na OH concentration
on millet straw digestibility (table 9) whilc chemical value of straw didn't
undergo any change (Table 10).
As emphasized by JACKSON (1979) 6 p 100 has been a good concentration.
The incubation time had no maJor influence in the imprevement of millet
straw. The minimal time of 24 hout-s is sufficient.
C O N C L U S I O N
The ruminant ut ilisation of ava ilabie cerea I straw could be greatly
Improved in Senegal 0
Early harvesti ng and conservation should be adviced to farmer.
Cereal straws represent an important source of energy, Optimal recuperation
could hclp fat-mers to meet hlgh demand of dry matter and energy for milk and
meat production.
Howevor their low concentration in nitrogen, minerals and digestiblo
energy requires a good supplemontatlon.
Preference should be glven to
agro-industrial by product available in the acrlas of cereal production.
In the grounut basin and the south, cerealstraw cari be supplemsntcd by
peanutt cake, cotton seed, sorghum, millet and rice brans.
Rice agro-industrial by products (rice polishing, rice Ix-an) in association
with rice straw cari achleve higher production levels in the southern and
northern part of Senegal.
In senegalese river valley, tho intensification of animal production could
ba realized through t-ho combinaison of rice straw, molasses, urea an rice bran
Import of feed ressources is not necessary in i-ha-t area.
Treatment with urea is the most promising alternative so!ution in order
to enhance stra
utilisation by ruminant, Urea is already availûbie at low cost,
Moreover it is an important source of non protein nitrogen and fat-mer have a traditic
tradition -tG use it as a fertilizer.
On farm research should be geared towards comparing the economic feasibility
of two alternative solution : treatment and supplementation of cereal si-rab:
with urea.
-18-
S U M M A R Y
Within the framework of agriculture and livestock association, low
quality trop frgslduOsemerg6 as one of feed ressources wich would play an
important role in the attempt of meeting dry mat-ter and energy requirements
of ruminants in Senegal.
In 1986, 887 820 tons of millet, maize, sorghum and rice grains have
been harvested.
Estimated
straw output
is 4 800 000 tons.
In supplemcnting this availabie low quality roughags preference should
be given to available agro-industrial by produclspresent in the area of coreal
production in order l-o avoid transport cons-train-k Groundnutt rice by product
and cereal brars have given very performing ration for rnf ik and meat intensive
or semi intensive production,
Treatment with urea is the rnost promising alternative solution in ordcr
fo entrante straw utilisation by ruminant. Urea is already available ai- low
cost moreover It is a sourct3 of non protein nitrogen and fat-mers have a traditior
to use it as fer-tilizer.
On farm research should be geared tocards comparing the xonomic feasabi-
lity of two alternative solutlon : treatment and supplementation of cereal straw
with urea.
-1 g-
B I B L I O G R A P H I E
CALVET (H.1, VALENZA (J.1, BOUDERGUES (R.1, DIALLO (S.1, FRIOT (D.1,
CHAMBRON (J.1 (1974) - La paille de riz dans l'alimentation animale au
Sénégal. 1. Analyses bromatologiques. Digestibilité in vivo et in vitro.
Bilans azotés et minéraux.
Rev. Elev. Méd. Vét. Fays trop , 27 (2)
: 207-220.
i
JACKSON (M.G.1 (1979) - Le tra i tennent des pailles pour l'alimentation des
animaux.
Evaluation de la rentabilité technique et économique,
Revue FAO ed., 1979, 68 p;
ISRA - LNERV (1977 1 - Rapport sur le fonctionnement de l'année
ISRA - LNERV (1980) - Rapport sur le fonctionnement de l'année
982. pp : 7879.
FRESTON (T.R.1, LENG (R.P..) (1984) - Supplementation of diets,based on fibrous
residues and by products.
In : Straw and other fibrous by products as feed
F. Sundstol and E. owen eds. Eisvier Press. Amsterdam H 373-413.
-2O-
A C K N O W L E D G E M E N T S
Authors are grateful to Mahawa MBODJ, Adama FAYE and Didier RICHARD for -l-h;;
critical review of this paper.
They are also endebted to Abdou FALL for holp In translating the text,
DEPARTEMENT DE RECHERCHES
AGRICOLE (I.S.R.A.)
SUR LES PRODKTI ONS
-..-----e----------
ET LA SANTE ANIMALES
LABoRATO I RE’ NATIONAL DE L’ELEVAGE
ET DE RECHERCHES VETERI NA I RES
DAKAR-HANN
< *
.
CEREAL STRAWS IN THE FEEDIN6
SYSTEM OF RU+IINANTS IN SENEGAL
S . F A L L , H . G U E R I N , C . S A L L a n d N D . MBAYE
,-
t-
R E F , N“ 69/AL. N U T .
’
I
SEPTEMBRE 1987
1
i
l
PAPER PRESENTED AT THE qTH ARNAB WORKSHOP/ANNUAL
GENERAL MEETING 19-23m OCTOBER 1987, b’4MENDA
- CAMERQUN
INTRODUCTION
A moving back of drought has been recorded in African sahelian countries
durfng the two pas-t years. Thus, pastures are in better condition, however the
availabie biomass remains insufficient. Alimentation is still the major
constraint to the improvement of livestock productiv i ty in Senega .
The challenge for research workers Iivestock technicians an d fat-mers
is to imagine a highly efficient feeding system using the available feed
ressources in'each region of Senegal.
Within the framework of agriculture and livestock association, low
quality trop residues emerge as one of feed ressources wich would play an
important role in the attempt of meeting dry matter and emergy requirements of
ruminants in senegalese agricuitural.
In 1986, 887 820 tons of maize, millet, sorghun and rice grain have bean
harvested. The estimated straw out put is 4 800 000 tons (FALL et al. 1987). This
aval table quantity is expected to Increase soon with the development of irri-
gation in senegal river valley. The main areas of production are the groundnut
basin, senegal river valley, Tambacounda and Casamance.
Prevlous studfes carried ou-t in LNERV have emphasized the low concentrs-
tion In digestible nutrient bulkiness and low Ingestibility of cereal straws
(CALVET et al. 1973, CALVET et Al. 1974, SALL, 1985, FALL et Al. 19871.
. . /. .*,
TABLE 1 : CEREAL STRAW SUPPLEMENTATION
I
I
1RATlONS
SPECIES
N&lBER
LEVEL BF
OF TRIALS
'-"'TF#TE
?A
Rice straw + Cotton seed
Sheep
7
26
Rice straw + Peanutt cake
1 1
7
10
Il
1 1
Cattle
2
615
!I
11
11
8
10
11
3
15
Rice straw + Rice poiishing
11
12
22
17
?V
Sheep
2
45
Rice straw + Rice break
1t
4
28,5
Rice straw + molasse + urea
t1
2
21,5
Rice straw + P*
Cattle
6
20
PJC = mixture w/w of rice polishing and maize bran
-3-
TABLE 2 : CHEMICAL VALUE OF AGRO INDUSTRIAL B'f PRODUCTS USED AS SUPPLEMENT
-
-
-%.
AGRO-INDUSTRIAL
Cotton
Peanutt
Mixture w/w
Rice
Rice
cake
Rice poiishing
seed*
+ Maize bran
polishing
break
N = 13
N"z 1
N = 14
N=6
-L-
Ash
41
52 k 5
103
63 2 3
153 + 7
Protein
193
504 2 50
135
119 ?- 53
81 Is: 0
Crude flber
250
28 2 9
78
65 + 30
70 * 1
Ether extract
184
7co
76
44 k 32
16 -: C
Nitrogen free extract
256
408 + 24
608
568 + 242
683 + 10
Calcium
1,5
1 J
191
0,8 rk 1.2
1,2
Phosphorus
5,l
6,2
935
10,7 + 0,o
* mean value indlcated by MONGODIN et TACHER 1979
-4-
Offered alone,
cereal straws cannot meet the maintenance requirement of
cattle, sheep or goat. They need to be associated with concentrates in order
to support intensive or seml
intensive milk or meat production. Chemical treatment
cari also improve ingestibility and digestibility of I ow quality roughages.
Supplementation and alkali treatment of cereal straw have been carricd
out in LNERV and IEMVT. The objectives of this paper is to describe experimental
procedures, discuss availablc results in order i-o set up a best way of into
gratlng cereal straws in the senegalese feeding system of ruminant.
EXPERIMENTAL PROCEDURES
Supplementation of rice straw
The main objectives of rice straw supp tementa-t ,ion was to improve rumen
environnement and increase straw digestibility. Rations were intended to allow
either maintenance or milk or meat semi intensive or intensive production.
Thus rice straw has been associated to agro-industrial by produc-tsdescribed in
table 2. Composition of rations species and number of tri.aIs are specified in
table 1.
Alkali treatment of cereal straws
NaOH and urea treatments of cereal straw have been comparatively carried
out.
TO avoid unjustifiable excessive
loss of water a semi humid method (JACKSON 1979)
has been applied.
Different levels of urea (3,5 and 6 p0 100) and sodium hydroxide (3, 4, 5
and 6 p. 100) have been tested.
The effect of urea treatment in dffferent species of cereal straw, millet,
sorghun, maize and rice, has been reviewed,
. . . / .*.
-5-
Evaluation of rations nutritive value
The nutritive value of supplemented rice straw, and alkali treated cereal
straws has been evaiuated by chemlcai analysis and in vivo digestibi iity -i-riais.
Chemical analysis Involved, organic ma-t-ter, crude fiber, crude protein,
NDF, ADF, lignin, silica and minerals.
In vivo digestibilitles have been carried ou-t with a lot of six cattle
or sheep. This experiment was brcken down into tow phases. 15 days of adJustment
and 6 of measurment.
-6-
TABLE 3 : SUPPLEMENTED RICE STRAW : CHEMICAL VALUE AND DIGESTIBILITY OF RATICNS
-
-
-
-
Rice straw Rice straw Rico straw Rice stral
+ cotton
+ Peanutt
i. Peanutt
+ Peanut 1
Rice straw
seed
cake
cake
cake
i
500 g/dsy
1 kg/day
250 ç/day
ANALYSIS
i
CATTLE
. SHEEP
SHEEP
CATTLE
CATTLE
CATLLE I
ût-ganic matter
j827?19}
-
824 +- 25
833 f 9
836 t: 1
840
-
N=29
-
N=7
N =8
N=3
N ~2
1.
Crude protein
25$r13
_
89 f 12
67 + 8
105 iY 1
49
N = 29
N=7
N=8
N=3
N=i?.
3
_I---
Crude fiber
360 C 34
335 24
f.
334 f 10
320 rt 6
325
N=29
-
N=7
N - 8
N=3
N=L
--.
"Ether extract
14 2 4
53 $r 10
11 I!I 4
13 t 3
l--0---- -4
/
N =29
-
N =7
N=8
N=3
H=Z
(
Free nitrogen exi-ract
428 -e 19
-
381 & 29
422
397410
456
-
-
-%-?3
N=29
N=7
N=8
N=3
--'
1
N = 2
WV.-
-
-
NDF*
555
503 2 42
N=l
-
N =6
t
- - 3
ADF*
428
-
497 i: 46
.*
N=2
N=6
o--e
Lignin*
62
-
75 f 10
- -
N-2
N - 6
-“-
*/
.-- -.--
Silica*
Calcium*
la9
2,4t 0.8
1.8 1- 0.4
1.6 k 0.0
f3-37-/
N -2
N=7
N .= 13
N=3
N = 2
--.. .-. --..
Phosphorus*
0.7
1.9+ 0.6
1.1 + 0.1
1.6 c 0.0
0.9t 0.0
-N=2
N=7
_ N - 8
N=3
N=2
_._ ,_._ -. . ..-
-
-
-
Magnesium *
-.
_
/I
--.--
Potassium*
-.^--_
C0gdt ppm
0.5 =
-
t
N 1
Cuivre ppm
5 . 8
=_/
N=l
-
-
-
-
- - - -
Zinc ppm
.-
43.1
- - - -
N =l
-.
Manganèse ppm
623
-
N =l
.--... -..-. _.
? Iran ppm
1186
. .
mm
-.
N =l
_---- -
Sodïum ppm
_.
.
Dry mai-ter dibstibifi-
562 5
49 k 3
502 4
54 -r- 3
57
___-.-- 63
ty qp. 100)
N = 15
N = 15
N=7
N >e fj
N =3
N=2
Organic matter digesti-
642 4
58 +4
57-L 4
63 1- 3
64
-----.-- 69
2ili-ty (p. 100)
N = 15
N = i5
N=7
N
Digestible organic
39+ 7
2% 4
28+ 2
49 =8
-: 6
N =3
N=2
_--._-
y
:~~
-*
matter intake
N = 15
N = 15
N=7
Il N=8
Digestible crude
3-+ 4
ot 13
45+ 10
35 2 9
76
34-‘-
protein
N = 15
N = 15
N=7
N = 9
M - 3
N = 3
Voluntary Intake
7411 9
485 7
60+ 4
95 15
t
100
101
--
g/ky p 0 75
,N ,
=15 N
=15
,
N=7
,N=8
N=3.
Iv=2._---
4. - li.- fi..
-7-
TABLE 3 : SUPPLEMENTED RICE STRAW : CHEMICAL VALUE
AND DIGESTIBILITY OF RATIONS
RATIONS
Rica straw Rlce straw Rice straw Urea greatec Urea greated
+ Peanutt
+ Rlce
+ rice
Rice straw Rice straw
Rlce straw
cake
pollshing
break
+ Urea
+ Molasses
+ rlce polishing
10 p 100 + maize
+ Urea
bran
ANALYS l
S
CATTLE
SHEEP
SHEEP
CATTLE
SHEEP
SHEEP
SHEEP
Organic matter*
049 Y? 19
793
841 c 2
838 k 5
a03 818
N = 14
N - 2
N - b
N =6
N = 1
N - 2
Crude protein*
63’ 1 1
147
52r 2
47 Yk 2
141 73
N = 14
N=2
' N-b
N - 6
N = 1
N = 2'
"rude fiber
2 6 0 f 3 5
258
255 + 6
242 - 8
369
344
N = 14
N=2
N = b
N - b
N = 1
N = 2
1 Ether extractr
312 = 22
17
29' 2
12 i 0
17 10
N
14
N = 2
N = b
N=6
N =
1 N 2
fiitrogen free extract
495k 16
371
505+ 4
583 k 3
356
SOL
N = 14
N.2
N=6
N =b
N = 1
N:i
N D F”
413
499
N=2
N - 2
A D F*
229
324
N=Z
N=2
Lingnine*
4 6
4 9
N=2
N - 2
Silica*
100* 9
15
1.6' 0.1
3.3 2.1
N - 6
N=2
N -6
N =
1 N-2
CaIclum*
2.0+ 0.4
3
1.7' 0.1
0.5 2.3
N = 14
N=Z
N = b
N =l
N=2
Phosphore*
4.0' 1,7
2.5
2.4+ 0;4
N = b
N - 2
N.6
Magnesium*
3.2? 0,6
2.2
N - b
N - 2
Potassium*
11.72 4.1
14.9
N=6
N=2
;y--j
Cobalt ppm*
0.6
0.5
N = 2
N=2
Cuivre
9.1
7.5
----J----
ppm
N=2
N = 2
-I
Zinc
43.8
47.3
.- ------- ++
ppm
N = 2
N=2
Manganèse ppm
5880
5600
N=2
N = l
Fer ppm
9 6 7
1103
N = 2
N =l
Sodium ppm
1938
N = 1
59i b
47
47
c
Dry matter digestibility
75+ 2
501t 4
46 50
,oo 1
N - 1 3
N = 2
N = 2
N =b
N -6
N i 1
=
N 2
Or;ga;FoJmattnr
dlgestihility
7c' = +3
55
57 =
79+ 1
58 f 3
P
N 13
N = 2
N
2
N=6
=
/
N56
5g
N
6
,
=
N 2
v
Digestible organlc matter
6 4 k19
intake*
N =
95+ 15
33 te 4
13
N -6
N ): 6
,
;I
Digestible crude protein
42 '7
43
107
332 1
loi 3
N = 13
N - 2
N=2
N=6
N;b
Voluntary intake
102 ? 22
6 5
g/kg p 0,75
53
N = 13
N = 2
N=2
137 = + 21
69 = +5
N 6
N 6
* g/kg DM
TABLE 4 : DIGESTIBILITY OF RICE STRAW IN COMPOSED DIETS COMPARED TO RICE
STRAW OFFERED ALONE
l-
--
R A T I O N S
SPECIES
ORGANIC MATTER
DIGESTIBILITY p 100
Rice straw
N =15
Cat-tle
645
4
Rice straw
N =15
Sheep
58-
4
+ Peanutt cake 500 g/day
N=8
Ce-t-t-le
59.62
2,7
19
1 kg/day
N= 3
Il
59.3+
2.0
fi
250 g/day
N=2
Sl
68.4&
0.6
+ Rice polishing
+ maize bran
N =6
II
80.9+
1.5
II
+ Rice polishing
N =12
73.8t
4.4
II
+ Rice break
N=6
Sheep
37.12
5.7
i
J
-9-
RESULTS AND DISCUSSIONS
I - RI CE STRAW SUPPLEMENTAI ION
1 .l - Peanutt cake
-
Peanutt cake is avai lable in the whole groundnut basin and in the
south of LSenegal .
Rations based on rice straw plus peanutt cake have been wel I consumed
(sec t a b l e 3).
TO improve digestibi lity of straw, the levei of peannutt cake should be
restricted. Previous studies (CALVET et AI. 1980, MBAYE et AI. 1983) have
shown the depressive effect of peanutt cake on organic matter digesti bi lity
(@ID) of straw when used in a too high percentage. Table 4 shows a significant
(P 50,051 depression of rice straw OMD at the level of 500 peanutt cake per
day (10 per cent).
Cuviously the improvement of rice straw OMD has not been
significant at the level of 250 g of peanutt cake pet- day. The same for the
rice straw @ID depression at 1 kg peanutt cake/day.
In conclusion, peanutt cake raises the nitrogen, energy and phosphorus
levels of rations based on rice straw the limitation of this concentra-t-e to
10 per cent of the diet and use of urea for nitrogen deficiency could allow semi
intensive meat production (sec tables
5 and 6)
1.2 - Coi-ton seed
Cotton seed cari be associated wfth tice straw in l-h2 south Senegal
(Casamance and Tambacounda 1. This concentrate represented 26 p 100 of the
ration based on rice straw.
/
.,,
..e
-lO-
Table 6
suggests an addition of urea to reach the semi intensive beef production
al lowed by energy level of the ration
1.3 - Rice agro indus-triai by products
Rice break, polishing an bran represent great feed ressource potential
avai lable in the aeria of rice production.
Used atone or in association (w/w) with maize bran, rlce polishing gives
an adequate supplementatlon of rice straw and improvod significantly (P ZG 0,05)
its OMD (Table 41.
In both cases the ration has been rich in energy and could support intensive
fattening of cattleWltha nitrogen source such as urea were added (Table 61
Rice break is rich in starch. It represented 28 per cent of the ration. Thic,
level has been too high and could explain the significant (F < 0,051 dépression
of rice straw OMD. This by-product should be reserved toputtry ,.
1.4 - Urea and mol asses
It is wel I documented that urea is a cheap nitrogen source able to
improve intake and OMD of low qua1 ity roughage.
Wi thout a goad energetic source, ruminant use of urea is poor.
In Senegal, molasses and rice straw are avai lable in the same aeria
(Senegal r i v e v a l ley). Jhe arsociatlon of rice straw, molasses and urea (20 p 100)
gives a mixture wel I consumed by ruminants. An addition of peanutt cake and
minerais could allow intensive or semi intensive beef fattening.
. . /
. l . .
i
TAELt
5 f JjUTRITIVE VALUE OF P?TIOffS BASE0 ON RICE STRAW _
I
l- INGESTIBILITY
ENERGY
T-
1
PFXITEIN
T Ml NERALS
--
NUMBER
RAT 10 NS
SPEC'ES OF TRIALS
g/lOO kg 9/k9
DMA
DCP
Calcium
hosphor
BW
p 0,75
-jig-zT p 100
3/kg DM
g/kg DM
9h
-.
-
-
RS*
CATTLE
15
1872 +209
74 c9
64 k4
0.5+ 0.0
-19.0
324
1 l 9
0.7
te
SHEEP
15
2053 *253
48 7-7
58 +4
0.e 0.0
-11.5
0 1: 13
RS + Cotton seed
tt
7
2545 -162
60 +4
57 +4
0.5+ 0.0
50 26.1
45 -t 10
2.4 +O,ô
1.92
I
RS ) Peanutt cake 500 g/day
CATTLE
a
2365 2355
95 +15
63 $13
0.41t 0.0 53.8.117..7
35 t 9
1.8 +0.4
1.110
RS + Peanutt cake 1 kg/day
II
3
,504 +52
100
64
0.52 0.0 72.8 +1.2
76
1 .6
1.6
RS + Peanutt cake 250 g/day
If
2
3485 $16
101
69
0.6& 0.0 44.8
34
2.3
0.9
R; + Rice poiishing
13
2599 5435
lC2 fL2
74 ?3
0.72 0.0 66.6 k1O.C
42 '7
2.0 20.4
4.02
'iS + Rice polishing
SHEEP
2
2890 295
65
55
0.5+ 0.1
._
43
-.
RS + Peanutt cake 10 p 100
??
2
2290 2143
53
57
0.3' 0.1 73.2
107
3
2.5
R; + Rice polishing + maize
bran
I
CATTLE
3351 +373
137 s21
79 +1
0.8+- 0.0 64.3 k3.1
33 +1
1.7 +0.1
2.42
RS * Rice break
11
3007 -1157
69 5
58 f3
~
0,4+ 0.0 21.3 26.2
10 +3
/
SHEEP
1695
40
56
0.4
74-ç
106
0.5
I
FI
2626 +559
61
59
0.45 0.1 43.5
32
2.3
-
-
*RS = Rice straw
<I
c
c
1
N9
TABLE 6
: LEVEL OF PRODUCTION ALLOWEO FOR UBT BY RATIONS BASED ON RICE STRAW
T
LEVEL OF
PRODUCT I ON
R A T I O N S
SPECI ES
EN ERGY
DIGESTIBLE
M I N E R A L S
CRUDE PROTE I N
T CA LC I ‘UM I PHOS PHORUS
RS
CATTLE
qaintenance+lOOg/day
: mai ntenance
mai ntenance
< mai ntenance
Tic
SHEEP
: Mai ntenance
c m3 i ntenance
- -
RS + Cc-t-ton seed 26 p 100
?9
lai ntenance+300g/day
IÛ i ntenance+ 100 g/dal r Flaintenance+lOO g/day Mai ntenanco+lO
TIS + Peanutt cake 500 g/day
CATT LE
99
+250g/day
Maintenance
Maintenance
< mal ntenance
I
i.S
11
1 kg/day
!t
99
+300g/day
!l
+750g/day
< mai ntenance
Mai ntenance+ 101
iS
IY
250g/day
il
9;
+500g/day
Mai nt enance
F!a1 ntenance+ 1 OOg/day
( mai ntenance
RS + Rlce poiishing 22 p 100
”
S?
+l kg/day
4ai ntenance+ 90g/day
mai ntesance
1 mai ntenance
RS + Rice polishing 45 p 100 SHEEP
99
+500g/day
99
+250g/dsy
RS + Peanutt cake 16 p 100
l?
: maintenance
91
+ l kg/day
vlai ntenence+25Og/day
Mai ntenance+501
RS + Rice polishing+ maize
bran 20 p 100
CATT LE
>Mai n-tenance+l kg/day
tt
+1 OOg/day
vlai ntenance
Maintenance+501
RS + Rice break 28.5 p 100
Mai ntenance+300g/da
< mai Ttenante
‘Jrea processed rice straw
SHEEP
+ urea 1.5 p 100
: Maintenance
4ai ntenance+560g/day
< mai ntenance
RS t (molasses + Urea )2oploo SHEEp
4oi ntenance+l OOg/day
Mai ntenance
-
.
>
TABLE 7 : UREA TREATMENT OF CEREAL STRA\\Y’
COMPARISIGN OF RICE, MI LLET, MAIZE, AND SORGI-UM STRAWS
-
-
M S V I g sec/kg (p 0,7!
Rice s t r a w
57.2 k 4.8
5 2 . 6 t 10.3
n - 6
Mai ze straw
. ..---
Cont ro 1
3 . 9
4 9 . 3
5 2”4
3 9 . 5 +
4 . 6
n = 1
n =6
n =6 - -
Processed
14.10
5 8 . 8
t 5.5
5 6 . 1 +-
3 . 4
n = 1
n = 4
n - 4
1
F?i I l e t s t r a w
Contro l
a.4
39.2
5 6.4
3 1 . 5 -
6 . 8
n = 1
n=5
n =4
e-e-
Processed
14.60
65.1
f 2.7
68 .4 i
3 . 4
n = 1
n =6
n =6
Sorghum stra#
;
ControI
1 4 . 2
n ~ ,
1
47.2
* n4z72
Iv 49.8 k
6 . 2
n
=
5
.
*
-14-
TABLE 8 : EFFECT OF UREA CONCENTRATION ON DRY MATTER DIGESTIBILITY AND
INTAKE OF PROCESSED CEREA4STRAWS .
I
UREA CONCENTRATION
DRY MATTER
DRY MATTER
CEREALS
p 100
DIGESTIBILITY
INTAKE
p 100
g/kg p. 0,75
L
w/w mixture
1
I
millet straw
3
42.4 4 1.1
N=4 3027
N=4
+ malze straw
5
56.0 k 8.4
N = 4 41 2 14
N =4
+ Sorghum straw
6
50.0 k 6.0
N=3 3425
N=3
TABLE 9 : DRY MATTER DIGESTIBILITY OF MILLET STRAW TREATED WITH Na OH
-
-
l
Na OH
CONCENTRATION
INCUBATION TiME'
30
40
50
60
24 hours
52.6
56.1
58.6
62.5
-"
48 hours
52.4
57.6
57,2
62.6
I
96 heurs
5202
56.4
57-9
62.8
1
Control = 36 p 100
From L.N.E.R.V. 1977 annual report
Q
Tl
-. - -.
0 OJ
L-l -l-i- 2iT- 3’
D Y
3 -l- 0’ -
N
%
. ul
PS ul
b CO
P m
-
$2
-.
P
-.
u3
P
-.
a
-
P
-.
0
w w
P
-.
r-3
.p
.s
-.
-
.b
-.
NNNN-NP
P
-*
-
CD
P
a.
o\\
-N-.lcl*--.lwEi:UI
0 0 N N
P 2
-.
w
P ‘&
~
N w N -4
a
$2.
S313S~ZXL~~~
d
------------
N
,w
-16-
I I - ALKALi TREATMENT OF CEREAL STRAW.
2.1 .- Urea treatment of cereal straw
Intake, digestibility and nitrogen concentration have been improved
by urea treatment of rice, millet , sorghum and maize straw (sec table 71,
Rice straw cannot be compared to otheîs roughages because it has been
sundried. Mai, e , millet and sorghun straw have been offerad humid. The nitrogen
levcl of rice straw has been under estimated.
Compared t-o maizo and sorghum straws, millet straw gave a superior improvi-
ment of intake and digcstibility whil e the first had a highcr capacity of nitt-e--
gen fixation.
Tho results in table 8 describe the effect of urea concentration on coreal
straw
mprovement . 5 p 100 has been the optimal lovel.
2 - Na OH troatment of millet straw
Avaflable results show a positive influence of Na OH concentration
on millet straw digestibility (table 9) whilc chemical value of straw didn't
undergo any change (Table 10).
As emphasized by JACKSON (1979) 6 p 100 has been a good concentration.
The incubation time had no maJor influence in the imprevement of millet
straw. The minimal time of 24 hout-s is sufficient.
C O N C L U S I O N
The ruminant ut ilisation of ava ilabie cerea I straw could be greatly
Improved in Senegal 0
Early harvesti ng and conservation should be adviced to farmer.
Cereal straws represent an important source of energy, Optimal recuperation
could hclp fat-mers to meet hlgh demand of dry matter and energy for milk and
meat production.
Howevor their low concentration in nitrogen, minerals and digestiblo
energy requires a good supplemontatlon.
Preference should be glven to
agro-industrial by product available in the acrlas of cereal production.
In the grounut basin and the south, cerealstraw cari be supplemsntcd by
peanutt cake, cotton seed, sorghum, millet and rice brans.
Rice agro-industrial by products (rice polishing, rice Ix-an) in association
with rice straw cari achleve higher production levels in the southern and
northern part of Senegal.
In senegalese river valley, tho intensification of animal production could
ba realized through t-ho combinaison of rice straw, molasses, urea an rice bran
Import of feed ressources is not necessary in i-ha-t area.
Treatment with urea is the most promising alternative so!ution in order
to enhance stra
utilisation by ruminant, Urea is already availûbie at low cost,
Moreover it is an important source of non protein nitrogen and fat-mer have a traditic
tradition -tG use it as a fertilizer.
On farm research should be geared towards comparing the economic feasibility
of two alternative solution : treatment and supplementation of cereal si-rab:
with urea.
-18-
S U M M A R Y
Within the framework of agriculture and livestock association, low
quality trop frgslduOsemerg6 as one of feed ressources wich would play an
important role in the attempt of meeting dry mat-ter and energy requirements
of ruminants in Senegal.
In 1986, 887 820 tons of millet, maize, sorghum and rice grains have
been harvested.
Estimated
straw output
is 4 800 000 tons.
In supplemcnting this availabie low quality roughags preference should
be given to available agro-industrial by produclspresent in the area of coreal
production in order l-o avoid transport cons-train-k Groundnutt rice by product
and cereal brars have given very performing ration for rnf ik and meat intensive
or semi intensive production,
Treatment with urea is the rnost promising alternative solution in ordcr
fo entrante straw utilisation by ruminant. Urea is already available ai- low
cost moreover It is a sourct3 of non protein nitrogen and fat-mers have a traditior
to use it as fer-tilizer.
On farm research should be geared tocards comparing the xonomic feasabi-
lity of two alternative solutlon : treatment and supplementation of cereal straw
with urea.
-1 g-
B I B L I O G R A P H I E
CALVET (H.1, VALENZA (J.1, BOUDERGUES (R.1, DIALLO (S.1, FRIOT (D.1,
CHAMBRON (J.1 (1974) - La paille de riz dans l'alimentation animale au
Sénégal. 1. Analyses bromatologiques. Digestibilité in vivo et in vitro.
Bilans azotés et minéraux.
Rev. Elev. Méd. Vét. Fays trop , 27 (2)
: 207-220.
i
JACKSON (M.G.1 (1979) - Le tra i tennent des pailles pour l'alimentation des
animaux.
Evaluation de la rentabilité technique et économique,
Revue FAO ed., 1979, 68 p;
ISRA - LNERV (1977 1 - Rapport sur le fonctionnement de l'année
ISRA - LNERV (1980) - Rapport sur le fonctionnement de l'année
982. pp : 7879.
FRESTON (T.R.1, LENG (R.P..) (1984) - Supplementation of diets,based on fibrous
residues and by products.
In : Straw and other fibrous by products as feed
F. Sundstol and E. owen eds. Eisvier Press. Amsterdam H 373-413.
-2O-
A C K N O W L E D G E M E N T S
Authors are grateful to Mahawa MBODJ, Adama FAYE and Didier RICHARD for -l-h;;
critical review of this paper.
They are also endebted to Abdou FALL for holp In translating the text,