INTERNATIONAL WORKSHOP ON “CROP RESIDUES IN...
INTERNATIONAL WORKSHOP ON
“CROP RESIDUES IN SUSTAINABLE MIXED CROP/LIVESTOCK
PARMING
SYSTEIUS
Organized by ICRISAT (INTERNATIONAL CROPS RESEARCH INSTITUTE FOR
THE SEMI-ARID TROPICS), and held from April22 to 26, 1996, in Patancheru,
Asia.
USE OF CROP-RESIDUES IN THE AGRICULTURAL SYSTEMS OF SENEGAL.
A Country Report
Invitatimal paper
bY
Cissé Maimouna
Institut S&x?galais de Recherches Agricoles, BP 2057, Dakar
ABSTRACT
This study involved a survey of animal production systems and an inventory of trop by-
products available in the farming sector in Senegal. Cattle are the dominant class of
livestock, followed by sheep and goats, although both contribute to the cash economy. The
major factor affecting livestock production is feed shortage during the dry season.
Overgrazing leading to degeneration of vegetal caver, and the recent drought conditions,
have made the situation worse. Several trop residues and agro-industrial by-products were
identified as alternative feeds and potential supplements. The constraints associated with
their efficient use are emphasized. More collaborative research between NARS within the
eco-region and strengthened partnerships with IARCs are needed to make better use of these
feed resources for increased animal production of benefit to the population, without adverse
effects on the environment.
INTRODUCTION
Senegal is situated in West Africa, on the atlantic toast, in the intertropical
zone between latitude 12’30’and 16O30’N and longitude 11’30’ and I7O30’ W. It has a
land area of 196, 722 km2 and a population estimated at 8 million inhabitants. Two
ecological zones cari be distinguished according to rainfall pattems, the Sahelian zone in the
North and the Sudano-Guinean zone in the South of the country. Rainfall is unimodal,
occuring betwen July and September, and ranges in average Erom 200 mm in the North to
1500 mm in the Sou& This short rainy season is followed by a long dry season from
October to June during which rain never occurs.
The basis of Senegal economy is agriculture. Agriculture employs more than
70% of the population, accounts for 13 % of the Cross Domestic Product @DP), and makes
an important contribution to export earnings (Etude sectorielle de l’elevage, 1982). The
livestock sector, although characterised by low productivity, contributes to about 6.5% of
The cattle population increased by only 6% from 1970-1977 to 1990-1994,
while the sheep and goat numbers increased by over 44.7% during the same period (cattle
2462,000 in 1970-1977 to 2,612,OtXI in 1990-1994; sheep and goats 2647,000 in 1970 to
3,831,OOO in 1990) (Direction de l’Elevage, 1970-1994). This trend is also a result of the
actual increased pressure on land for cropping.
2. Role of livestock in major agricultural systems
Animal production involves both non-ruminants and ruminants, and a variety
of systems more or less integrated with crops (Table 2). Three major agricultural systems
closely related to agro-ecological zones have been identified:
.the pastoral system in the sylvo-pastoral zone in the North and East,
.the agro-pastoral system in the Centre and in the South,
.the peri-urban system.
-The pastoral system
The livestock management consists of a transhumant pastoralism practiced by
the Peuhl ethnie group whose major means of livelihood is almost exclusively cattle
production on extensive grazing land area (Diop, 1989). Household income and food supply
depend mainly on livestock.
Cattle are reared on natural pastures with sheep and/or goats and have to trek
great distances in search of fodder and water (Diop, 1987; Diop 1991). Nutrition is a major
limiting factor in pastoral systems. Availability and adequacy of feeds fluctuate with
seasons. Pasture productivity varies from 100 to 2,000 kg of dry matter per hectare from
year to year, and from 500 to 1,800 kg dry matter according to the types of pastures
(Boudet, 1984; Richard et al., 1989). Nutritional value of natural forage has been
extensively investigated in Casamance, in the South of the country (Boudet, 1970) and in
3. Impact of mechanization on the use of livestock in agricultural systems
In the Senegalese peanut basin, population growth and the extensive use of
animal traction have favored the excessive expansion of cultivated land to the detriment of
the pastoral land area. Traditional practices of maintaining soi1 fertility have been disturbed
by pastoral land restrictions (Faye, 1993). Pressure on land and the encroachement of
cropping lands on pastures has caused a reduction in the cattle population in the groundnut
bassin and a shifi to the use of cows for draught purposes. The use of horses and donkeys
for cropping and transport bas increased.
Agricultural production in the country has been better organised over the past
two decades and more and more development plans give priority to food production for
domestic use, with resultant increase in the agriculture-based industries.
With the decline and degradation of grazing lands through overgrazing and
the expansion of arable cropping, agricultural by-products take on greater significance. For
example, cotton production increased from 1,000 tons in 1987 (Plan d’Action pour
l’Elevage, 1988) to 50,000 tons in 1991-1992 (Direction de l’Agriculture, 1992).
Consequently, the use of cotton seed, a major protein source, greatly increased for beef and
sheep fattening in the Center and in the South of the country. In 1986, 887,820 tons of
maize, millet, sorghum and rice grain were harvested. The estimated straw output is
4,800,000 tons (Fall et al., 1989). An increase in available quantities of straws could be
expected with the development of irrigated cropping in the Senegal river valley and
mechanisation.
II. USE OF CROP RESIDUES AS LIVESTOCK FEED RESSOURCES
1. Farmer’s current practices on utilizing trop residues as a source of
livestock feed in major agricultural systems.
Quantitative estimates of trop residues are not usually reported in national
statitics. Groundnut and millet are the major crops in Senegal. Groundnut haulms are
therefore the most abundant trop residue (Table 3). Millet straws are second in importance.
There are widely used as animais feed. The other trop residues and agro-industrial by-
products (Table 2) include cereal and legume straws, wheatbran, dried brewers’grains
(spent grains from the breweries), oilseed cakes, cottonseed cake and palmkernel) and
cereal bran. Without the availability of trop residues, ruminants could hardly survive the
long dry season.
In years where statistical data on agro-industrial by-products have been
reported, large quantities are found. High quantities of them (groundnut cake, cotton seed,
pahnkernel cake, molassis) are however exported (Etude sectorielle de 1’6levage au Senegal,
1982).
3. Current practices used in processing trop residues
Cereal straws and groundnut haulms are scattered on the farms after
harvesting the grains. Sorghum stalks retain a better quality if harvested early, dried and
stored off the ground on man made storage facilities. Bundles of rice straw, weighing 10-13
kg, and groundnut haulms are marketed as animal. The main customers are transport
businesses with draft animals, and the peri-urban milk and meat producers.
Most of the groundnut grown in the country is locally processed into oil. The
remaining cake is a valuable source of energy and protein. The industrial cake is exported.
The domestic cake and cereal bran are the major by-products useful as animal feed which
are produced at the village level. There is a certain import of wheat processed locally into
flour. However, the quantity of wheat bran appears to be limited.
Cereal trop residues are important feed resources in the mixed farming
systems. However these residues are high in lignocellulose compounds and are
characterized by low protein content, and low digestibility and voluntary intake (Sall, 1984;
Fall et al., 1989). When fed alone to ruminants, as practiced by several farmers, they cari
not support maintenance requirements.
A great deal of research on forages has been done in various research centres
and feeding recommandations were formulated for farmers. Improvement in the nutritional
value of straws with physical treatments and supplementation with other by-products (Table
S), and good animal performances were reported with on station-research. Chemical
treatment of straws (Blancou and Calvet, 1977) is restricted by COS, technical ability and
safety. However, urea seems promising (Fall et al., 1989; Cisse et al., 1995b, 1996a;
Gongnet et al., 1996), because it is cheap and easy to obtain at the village level. The
evaluation of its profitability at the farm level is going on in the Senegal valley river with
rice straw and in the peanut basin, in the Center, with natural pasture straw.
4. Current practices used to supplement trop residues
In the agropastoral system, farmers commonly use trop residues
supplemented with artisanal groundnut cake, and cotton seed, or they cari mix various trop
residues for animal feeding.
In the agricultural areas, farmers generally waste feed resources and
consequently animals are over or underfed. There is an often ineffective coliection of the
groundnut haulms which is by far the most important and the best quality feed for animals.
If they still contain many leaves, groundnut haulms cari support daily gains of 0.5 kg
liveweight for thin cattle afier a dearth period. Millet, maize and sorghum straws represent
30 to 50% of the cattle diet during the dry season and a smaller part of the small ruminant’s
diet, in agro-pastoral zones (Richard et al., 1989).
Many years of research on the nutritive value of every type of trop residue in
several combinations showed technical advantages of using these resources (Table 5) as
animal feed. The technologies generated (diets formulated with many agro-industrial by-
products) without economic analysis are beyond the reach of farmers. Research on both
pasture and agricultural by-products has had a very limited impact on livestock productivity
in the small-scale farming systems.
5. Major constraints on utilization of crops residues as livestock feed
The major constraints associated with the use of by-products are their
bulkiness, transportation, storage and processing.
After harvesting the grains, cereal straws have to be bulked and transported
to the villages and stored. The fnst problem encountered is transport both on farm and on a
regional basis where by-products may be located in a different area to livestock.
The second problem is the amount of labour required to collect and store the
trop residues. People are busy harvesting crops and do not take time to collect and store the
trop residues (Fall, 1986). Another constraint is the actual manner of storage, whether on
platforms, in the field, fenced, etc...Moreover, there are no machines in the villages to
process these straws for incorporation in diets for ruminants. In the harvesting process,
development of simple machinery such as choppers or chaffcutters would be benefïcial in
reducing by-product particle size.
Inadequate and inefficient use of the available technology is also a major
limitation to increased animal production.
6. Nutritive value of trop residues
An important study was carried out to determine the nutritive value of (1)
native herbages of natural pastures in the Sahelo-sudanian zone, (2) fodder grasses
cultivated under irrigation and (3) some trop residues and agro-industrial by-products
(groundnut haulms and cake and cereals straws) encountered in Senegal. The determination
of their chemical composition (Table 3), digestibility and feeding triais results allowed the
establishment of Feed Tables (Richard et al., 1989). However, other studies are needed to
specify the feeding value of each by-product with high potential.
The feeding values of millet, maize and sorghum straws are very low. Their
dry matter digestibility ranged from 42.8 to 49% (Sall, 1984, Fall et al., 1989, Gongnet et
al., 1996) and their organic matter digestibility depends on the leaf/stem ratio (0.2-0.35),
and ranges from 40-45% for the entire straws and from 50-55% for the leaves. Rice straw
has a higher organic matter digestibility (56%) (Richard et al., 1989) than the other straws.
The energy content of groundnut haulms varies between 0.50 to 0.72 UFL/kg
DM and their digestible protein content between 40 to 74/kg DM, depending on the
leaflstem ratio (0.2 to 1.5 according to harvesting practices) (Richard et al., 1989). Rice
bran has a chemical and a nutritive value negatively affected by high levels of silica (12.2%
DM) and ADL (8.2% DM), as a consequence of a high proportion of hulls.
Most of the forages have insufficient mineral content (P, Ca, Na, CU and Zn) to
meet the requirements of livestock (Cissé, 1985; Guérin et al., 1989; Cisse et al., 1996b).
Some trace elements content such as CU and Zn are, in most of the forages, under the limit
of deficiency .
Studies on the toxicity of trop residues (gossipol content of cotton seed, and
other toxic constituer@ like alkaloïds, glucosides, polyphenols, hydrocyanic acid, oxalic
acid, etc...) are very scarce. However, detoxification of groundnut cake against aflatoxine
is required for EU exports.
7. Opportunities for collaborative research on strategies for using trop
residues as animaf feeds.
Feed is the principal constraint among the non genetic factors affecting
animal production, particularly during the dry season. Fodder is of poor nutritional value
for most of the year due to the rainfall pattern, and trop residues and other feed resources
are greatly underused. This situation Will be worsened if livestock productivity and
population increase. However, there is an immense potential for improving animal nutrition
and therefore production by using trop by-products. The use of farm-produced by-products
(stovers, straws, bean and groundnut haulms and household offals) and agro-industrial by-
products as animal feed is an efficient and ecologically sound use of feed resources.
Attention must be given to research on forage production and agricultural by-
products which are an important feed resource in animal production systems. Increased
intensification and efficiency in the use of feeds is most important and emphasis should be
given to feeds that do not compete with human food.
In the sylvo-pastoral area where the production system is pastoral, increased
fodder production Will be possible with the rehabilitation project to improve water
availability in fossiled valleys, as are corrections of minera1 deficiencies. Adapted forage
cari provide nutrients for ruminants. More productive and high yielding forage crops need
research. The agronomie characteristics of these forages need to be determined in order to
achieve maximum bene& from them. Fertiliser requirements, frequency of cutting, cutting
height, grassllegume mixtures and other factors affect the yield and nutritional value of
forages.
availability of support services and infrastructure that producers need in order to make best
uses of by-products.
Government policy should promote the optimal use of the local feed
resources in the animal industry and improve the capacity of the private sector capacity to
respond to the market environment. With the devaluation of the CFA franc by 50% in
February 1994, exports of agro-industrial by-products increased.
9. The institutions involved in research and development of livestock feed
based on trop residues: their spcciality and liukages with advanced institutions in
developed countries and with IARCs.
In the recent past, some international institutions such as FAO, CIRAD, ILRI
through AFRNET and IDRC have funded research projects on the use of by-products, in
Senegal .
Factors limiting the utilisation of technical packages at the small-holder level
include poor coordination between research institutions and development organisations.
Researchers do not get enough feedback information to enable them to plan their research
activities based on the needs of farmers. SO, projects are usually proposed on their own
perceived problems.
In order to facilitate the immediate diffusion of technologies generated by the
scientists into the farming systems, a well-organised extension system is required. It is also
important to improve linkages between researchers and extension workers to share
experiences (through joint research propos&), and the extension services have to be
strengthened through training extension staff.
It is also important to note that, in Senegal as in several developing countries,
the level of research fùnding and the infrastructure in terms of laboratories and facilities and
trained manpower are limited. Partnerships between NARs, IARCs and other regional
institutions on common research needs on the use of trop residues has to be strengthened.
This cari be done through a better exchange of information, training, participation in
workshops and other scientific meetings.
Acknowledgments
1 wish to thank Drs Tom Cusac, Head of NRBAR/ISRA (USAID), Abdou Fall, Head of
ISRA/URA Productions Animales, and my colleague Cheikh M’Baye Boye for critically
reading the manuscript.
References
Adegbola A.A., Smith O.B., 1982. Use of pasture and agro-industrial by-products for
ruminant production in West Africa. FAO Animal Production and Health Paper, n032, 115
126.
Ba-Diao M., 1991. Les systèmes d’&levage dans la zone des Niayes au sénégal. 1.
L’t?levage traditionnel. Etudes et Documents, ISRA, vol. 14, 29p.
Blancou J., Calvet H., 1977. Fermentation microbienne de produits végétaux destines à
l’alimentation du bétail au Senégal. Physio-Nutrition, LNERV, ISRA, 15~.
BO Kohl, 1982. Les aliments du b&ail sous les tropiques. Données sommaires et valeurs
nutritives. Collection FAO, Production et sante animales, no 12.
Boudergues R., Calvet H., 1970. Note sur la digestibilittc des coques d’arachide utilisees en
alimentation animale. Rev. Elev. Med. Vét., Pays trop., 23, 493-502.
Boudet G., 1970. Pâturages naturels de Haute et Moyenne Casamance (Republique du
sénegal) , Etude Agrostologique, n ’ 27, IEMVT .
Buldgen A., Detimmerman F., Piraux M., Compère R. 1992a. Les techniques d’embouche
de moutons en région soudano-sahelienne sénégalaise. Rev. Elev. Med. vet. Pays trop., 45,
321-328.
Buldgen A., Detimmerman F., Sa11 B., Comp&re R. 1992b. Etude des param&res
demographiques et zootechniques de la poule locale du bassin arachidier sénégalais. Rev.
Elev. Med. vét. Pays trop., 45, 341-347.
Buldgen A., Lemal D., Steyaert P., 1990a. Engraissement de taurillons et de mâles de race
Gobra à partir de sous-produits agro-industriels melasses au Seriegal. Tropicultura, 8, 107-
111.
Buldgen A., Piraux M., Deletre J.L. et Compkre R., 1990b. Embouche de taurillons de
race Gobra en milieu villageois du bassin arachidier sénégalais. Bull. Rech. Agron.
Gembloux, 25, 251-262.
Buldgen A., Piraux M., Dieng A., Comp&e R. 1993. Mise au point de techniques
d’embouche bovine villageoise dans le bassin arachidier. WAWRMZ, 76, 27-34.
Calvet H. et Denis J.P., 1974. Embouche intensive du mouton peulh-peulh senegalais,
Physio-alimentation, LNERV, ISRA, 33~.
Calvet H., 1977. La coque d’arachide en alimentation animale. Physio-Nutrition, LNERV,
ISRA, sp.
Calvet H., 1979. Les sous-produits agro-industriels disponibles au Sénégal et leur utilisation
en embouche intensive. Actes des IX Journées Mklicales, 15-20 janvier 1979, 51~.
Calvet H., Boudergues R., Friot D., Valenza J., Dia110 S., Chambon J., 1974a. La paille
de riz dans l’alimentation animale au Sénégal: 2-Biochimie du rumen - Embouche intensive
- Conclusion. Rev. Elev. Med. Vet. Pays trop., 27, 347-362.
Calvet H., Valenza J., 1973. Embouche intensive de ~&US peuhl sénégalais à base de paille
de riz. Rev. Elev. Med. Vét. Pays trop., 26, 105-l 16.
Calvet H., Valenza J., Boudergues R., Dia110 S., Friot D., Chambon J., 1974b. La paille
de riz dans l’alimentation animale au Sénegal: l-Analyses bromatologiques-Digestibilite
in
tivo et in vitro. bilans azotes et minéraux. Rev. Elev. Med. Vét. Pays trop., 27, 207-220.
Calvet H., Valenza J., et Boudergues R., 1969. Coque d’arachide et alimentation du bétail.
Colloque sur l’élevage, Décembre 1969, Fort Lamy.
Calvet H., Valenza, Friot D., et Wane A.M., 1973. La graine de coton en embouche
intensive, Performances comparées des zébus, des taurins et des produits de leur
croisement. Rev. Elev. M&l. vét. Pays trop., 26, 349-362.
Cisd M., 1985. Etude des carences minérales au Sénégal: Exploitation des resultats acquis
pour l’ébauche d’une cartographie. Mémoire de confirmation. Réf. 75 Al.-Nutr.,
LNERV, ISRA, 12Op.
Cissé M., 1991. Situation actuelle de la production laitiere au Sertegal. LNERV, ISRA,
Dakar, 13~.
Ciss$ M., Awad M., Ahokpé B., 1993. Comportement alimentaire et performances laitières
des chèvres saheliennes exploitant des parcours naturels. In Proc. biennial Conf. African
Feed Res. Network, 6-10 Dec., Harare, Zimbabwe, in press.
Cisse M., Fall S.T., Ditaroh D., Korréa A., 1992. Changes in body condition of zebu
cattle according to the level of feeding. In Proc. Al1 Africa Conf. Anim. Agric., 23-27
Nov., Nairobi, Kenya.
Cisse M., Fall S.T., Korréa, 1995a. Une vue de l’évolution mensuelle de l’état corporel
des zébus Gobra au cours d’une op&ation d’embouche à base de sous-produits agro-
industriels. Fiches techniques ISRA, ~01.6, nOl, 18 p.
Cissé M., Fall A., Sow A.M., Gongnet P., Korrea A., 1995b. Effet du traitement de la
paille de brousse à l’urée et du niveau alimentaire sur les variations de poids vif et de notes
d’etat corporel des ovins saheliens en saison seche. Int. Symp. Nutr. Herbivores, Sept.95,
Montpellier, Ann. Zootech., in press.
Cissé M., Fall A., Sow A.M., Gongnet P., Korréa A., 1996a. Traitement de la paille de
brousse à l’urée 4% et utilisation pour l’entretien des animaux en saison Seche et pour
l’embouche. Fiches techniques ISRA, en cours d’edition.
Cissé M., Gu&in H., Prince E., 1996b. Les carences min&ales existent au Senegal.
Comment corriger ce deficit nutritionnel?. Notes et Document ISRA, ~01.6, n’3, 22~.
Cissé M. Ly I., Manga R., 1995~. Evaluation of body lipid change in the Sahel goat
according to the level of feeding by the condition scoring method. Int. Symp. Nutr.
Herbivores, Sept.95, Clermont-Ferrand, Ann. Zootech., 44, Suppl., 330.
Cissé M., Seck M., Ba-Diao M., Sane 1. 1996c. Effet de la somatotropine bovine sur les
quantites de lait recolte après tétee chez les vaches Djakore “Bos indicus x Bos taurus”, au
Senegal. An. Zootech., ~01.45, in press.
Denis J.P., Calvet H., Friot D., Vassiliades G., 1976. Embouche intensive du mouton
Touabire sénegalais. LNERV, ISRA, Dakar, 16~.
Denis J.P., et Valenza J., 1971. Exteriorisation des potentialités génétiques du zébu peuh1
senégalais (Gobra). Rev. Elev. Med. v& Pays trop., 24,409-418.
Denis J.P., Valenza J., et Thiongane P.I., 1972. Exteriorisation des potentialités du zébu
Gobra. Resultats des abattages pratiqués en 197 1. Rev. Elev. Med. vet. Pays trop., 25,
245-257.
Denis J-P., Valenza J., et Thiongane P.I., 1974. Extériorisation des potentialités du zébu
Gobra. Résultats des abattages pratiqués en 1972. Rev. Elev. Med. vét. Pays trop., 27,
109-l 14.
Dieng A., 1984. Utilisation des sous-produits agricoles et agro-industriels disponibles le
long du fleuve Sénegal. Th. Ingenieur Agronone, Fac. SC. Agr. Gembloux, Belgique.
Diop A.T., 1987. Les ressources de l’aire pastorale de Tatki. Inventaire et etude du mode
d’exploitation. Proposition de plan d’aménagement et de gestion rationnelle. Ref 17
Agrosto., LNERV, ISRA, 19Op.
Diop A.T., 199 1. La gestion des parcours de l’aire d’influente du forage de Tatki.
Relations entre données de vegetation, taux d’exploitation et transhumance. Réf. 5
Agrosto., LNERV, ISRA, 18~.
Diop M., 1989. Les systèmes d’elevage dans le Ferlo: &ude synthetique de la situation
actuelle. Séminaire FAPIS, 22-26 Mai 1989, Dakar.
Diop P. E. H., Cissé M., Sow A.M., 1992. Performances de reproduction et de production
laitière de la Jerseyaise au sénegal. In Proc. VII International Conference of Institutions
of Tropical Veterinary Medicine, Sept. 1992, Abidjan, Côte d’ivoire, 368-378.
Direction de 1’Elevage. Rapports annuels de 1970 à 1994. République du Sdnegal.
Direction de l’Agriculture, 1992. Rapport annuel des activités agricoles. Minist&re du
Développement Rural et de l’Hydraulique, République du Sénégal.
Direction de I’Elevage, 1992. Conseil Interminist&iel sur 1’Elevage. Minist&re du
Développement Rural et de I’Hydraulique, Republique du sénegal.
Etude sectorielle de l’élevage au Sénégal (Situation et perspectives), 1982. Etude Banque
Mondiale/FAO, Minist&re du Développement Rural, Dakar, S&régal, 3-46.
Fall A., 1986. Feasability evaluation for improved livestock sector for the agropastoral
production system of the Upper Casamance, Senegal. Th. Master of Science: Animal
Science, Michigan State University, USA.
Fall S.T., 1993. Valeur nutritive des fourrages ligneux, leur rôle dans la complementation
des fourrages pauvres des milieux tropicaux. Th. Doctorat Zootechnie, ENSA Montpellier,
139p.
Fall S.T., Cissé M., Richard D., Ditaroh., 1993. Production intensive de viande bovine au
Sénégal. Rapport de contrat ISRAKRDI, Res. Al/Nov. 1993, LNERV/ISRA, Dakar.
Fall S.T., G&in H., Sall C., et M’Baye N., 1989. Les pailles de c&?ales dans le systeme
d’alimentation des ruminants au Senegal. ISRA, vol 2, no 1, 38~.
Favre B., Calvet H., Valenza J., et Wane A.M., 1973. Nouvel essai d’embouche intensive
avec les sous-produits de l’industrie cotonnière. LNERV, ISRA, Dakar, 37~.
Faye A., 1993. Situation et perspectives de l’elevage bovin dans les systèmes agro-
pastoraux denses de la zone sahelo-soudanienne. Le cas du Sud du Bassin arachidier du
Seriegal. These doctorat en Sciences Agronomiques, ENSAM, Montpellier, France.
Faye A., Landais E., 1985. L’embouche bovine paysanne dans le Centre-Nord du bassin
arachidier au Sénegal. In: DSAKIRAD, Relations Agriculture-elevage, 304-311.
Faye M., 1981. Etude de la rentabilité de l’utilisation de rations à base de sous-produits
agricoles et agro-industriels en embouche bovine au Sénegal. Th. Doct. Med. Vét., n020,
EISMV, Dakar.
Gongnet G.P., Fadiga S., Cissé M., 1995. Amélioration de la valeur alimentaire de la
paille de riz par le traitement à l’ur& et la complémentation en cereales chez le mouton
Peulh skrégalais. Soumis pour publication.
Gu&in H., 1987. Alimentation des ruminants domestiques sur pâturages naturels sahéliens
et sahelo-soudaniens. Etude methodologique dans la région du fer10 au Sénégal. Th.
Doctorat Ingénieur, spkcialite Agronomique, ENSA, Montpellier, 21 lp.
Gu&in H., Cissé M., Heinis V., 1989. Composition minkale des fourrages. In Elevage et
potentialités
pastorales
saheliennes.
Syntheses
cartographiques:
Senégal,
CTA/IEMVT/ISRA, P 8.
G~&in H., Friot D., M’Baye Nd., Richard D., Dieng A., 1988. Régime alimentaire de
ruminants domestiques (bovins, ovins, caprins) exploitant des parcours naturels saheliens et
soudano-saheliens. II. Essai de description du régime par l’étude du comportement
alimentaire. Facteurs de variation des choix alimentaires et consequences nutritionnelles.
Rev. Elev. Med. vet. Pays trop., 41,427-440.
Gueye 1.S et N’Diaye A.L., 1979. L’utilisation des produits et sous-produits agroindustriels
en elevage. Aspects economiques. In Actes des IXbmes Joumees Médicales, 15-20 janvier
1979, 51p.
Kane B., et N’Diaye M., 1982. Utilisation des sous-produits agricoles et agro-industriels
dans l’alimentation du bétail au Sénégal. Production et Santé animales, Rome FAO, no 32,
136~.
Lemal A., Faye J-C., Buldgen A., Compkre R., 1989. Influence de la proportion de
melasse liquide sur la valeur alimentaire des rations pour ruminants composées des sous-
produits disponibles dans la val& du fleuve Sénegal. Bull. Rech. Agron. Gembloux, 24,
315-328.
Lhoste P., 1987. L’association agriculture-elevage. Evolution du système agropastoral au
Sine-saloum (S&égal). Maisons-Alfort, IEMVT, 1987, 314~. (Etudes et syntheses de
I’IEMVT n”21).
Ly C., 1989. La politique de développement de l’dlevage au Senegal: Repères sur
l’evolution, les réalit& et les perspectives de l’elevage des bovins et petits ruminants, 1960-
1986, n’l, ISRA/CRDI, 62~.
M’Baye M., 1988. Les productions bovines au Sertegal. In Actes de l’atelier du CIPEA sur
les Recherches en Productions bovines associees lait-viande en Afrique de I’Guest, Ibadan,
24-27 Octobre 1988, Nigeria.
Plan d’Action pour l’élevage,
1988. Ministère du Développement Rural et de
l’Hydraulique, République du Senegal, 76~.
Richard D., Guérin H., Fall S., 1989. Feeds of tbe dry tropics (Sénégal). In: Ruminant
Nutrition, R. Jarrige Ed., Paris, France, INRA and John Libbey Eurotext, p.325342.
Sall B., 1987. Comparaison de l’utilisation par les bovins et par les ovins d’aliments
fabriques à partir de sous-produits disponibles au Senegal. Th. Doctorat v&%inaire, no 1,
EISMV, Dakar.
Sali C., 1984. Complémentation de la paille de riz en fonction des objectifs de production:
choix d’une complémentation azotée, choix d’une complementation énergetique.
LNERWSRA, Dakar, 14~.
Seck P.A., 199 1. Progres techniques et satisfaction des besoins légumiers dakarois.
Réflexions et Perspectives, ISRA, vol. 2, no 1, 33~.
Sow A., 1991. Contribution à l’&ude des performances de reproduction et de production
laitière de la jersiaise importe% au Sénégal: Exp&ience de la SGCA. These de Doctorat
v&%naire, no 13-, EISMV, Dakar.
Steyaert P., Buldgen A., Compere R., 1989. Embouche intensive des taurillons de race
Gobra à l’aide de sous-produits agricoles en provenance de la val& du fleuve Sénégal ou
d’ensilage de mil complément& Bull. Rech. Agron. Gembloux, 24,297-313.
Table 1: Trends in livestock species in the last two decades (Direction de
l'élevage, rapports annuels 1970-1994)
____________-_-----_------------------------------------------------------
Livestock
Population (,OOO)
B change
species
_------------_---------~-
over the period
1970/77
1983/89
(1970-1989)
____-_------~_------~-~~~---~-~~~~~~~~~~~~-~~~~-~----~~-~-~~~~~~~~~~~~~~~~
Cattle
2462
2397
-3
Sheep & goat
2647
4471
+69
Pigs
256
204
-26
Horse
209
289
i-38
Came1
7
9
+43
Poultry
10500
____________-__-_-_-------------------------------------------------------
Table 2: Major agricultural systems in different agro-ecological zones in
Senegal
_ _ ________________---_------------------------------------------------
Agro-ecological
Major agricultural
Main Livestock Predominant Feeding
Zone
sys tems
Products
System
_________----__-----------------------------------------------------------
Sahelian
Goats/cattle/sheep
meat
Pasture grazing
(ZOO-5OOmm)
Rice, sugar-cane
milk
By-products
vegetables:tomatoes,
onions, beans, cassava
fruit: water melons
Sahelo-soudanian
Cattle/sheep/goats
meat
Pasture grazing
(500-7OOmm)
groundnut, millet
milk
Groundnut haulms
sorghum, maize
Cereal straws
Vegetables: tomatoes,
Commercial concen-
potatoes, beans carrot,
trate
cassava and fruits: mangoes,
oranges
Soudano-sahelian
Cattle/sheep/goats
meat
Pasture grazing
(700-9OOmm)
Groundnut, millet
milk
Groundnut haulms
sorghum, maize, cotton
Cereal straws
Cotton seed
Soudanian
(900-12OOmm)
Cattle/sheep/goats
Meat
Pasture grazing
Cotton, Groundnut
Groundnut haulms
millet,sorghum, maize,
Cotton seed
Cereal straws
Soudano-guinean
Cattle/goat/sheep
Meat
Pasture grazing
(1200-18OOmm)
Rice, groundnut
trop residues
millet, sorghum, palm-
Browsing tree-
trees, vegetables: beans,
foliages
cassava, fruits: banana
mangoes, oranges
----_-----------
________-_-----_-__---~-----~--~-~--------------------~
Table 3:
Agricultural
and
agro-industrial
by-product feed resources
available in Senegal
Feeds
Quantities (tons)
References"
Rice straw
170,000
Maize straw
102,633
Millet straw
592,505
Sorgho straw
78,094
Groundnut haulms
1,500,000
Bean haulms
Wheat bran
20,000
Rice bran
10,000
Millet bran
Wet brewers'grain
1,000
4
Groundnut husk
Cotton seed
50,000
3
Tomato industrial
dehydrated residues
Groundnut cake
100 à 300,000
Cotton seed cake
5,000
Cotton seed husk
8,800
Palmkernel oil cake
4,000
Molassis
30,000
Bagasse
300,000
*l.Etude sectorielle de l'élevage au Sénégal, 1982
2.Plan d'Action pour l'élevage, 1988
3.Direction de l'Agriculture, 1992
4.Direction de lIElevage, 1992.
Table 4: Nutritive value of some agro-industrial by-products available in
Senegal
Constituents*
_________--_----- ___________-_- ---_--_-_-_-_-----
Crop residues
DM%
CP% CF%
DMD Ca
P
CU Zn
-_--w-m -______-_- ---
-__----
-___________
(on a dry matter basis) %
g/kg DM
(mg/@' DM)
Rice straw
92.3
23
34.5 42.8
1.7
5.8 44
(Oryza sativa)
Millet straw
85
56
41.4
39.2
1.6 2.3
4.0 14.7
(Pennisetum americanum)
Sorghum straw
77.4
39
40.3
47.2
-41
.43
17.9 76.5
(Sorghum bicolor)
Maize straw
86
38
38.6 49.3
2.0 1.5
(Zea mays)
Bean haulms
89.3
13 29
1.35 0.29
(Phaseolus sp.)
Groundnut haulms
87.2
10.7
34.2
54.8
9.2 1.2
5.6 19
(Arachis hypogea)
Natural pasture straw
Groundnut husks
98.6
61
34.8
18.4
0.6 0.4
Millet bran
83.9
13.9 20
1.1 5.1
Rice bran
93.3
51
76
0.8 3.4
Cottonseed
86.6
20.6 33.0
Cottonseed husk
93.2
70
48.9
1.3
1.4
Cottonseed cake
92.3
10.3
30.6
1.5 12.7
Molassis
10
56
0
7.3
0.7
Maize bran
90.4
9.8 8.9
;.2 04
4.6
.14
Groundnut cake
97.8
48.5 50
Wet brewers'grain
22.9
5.0 4.6
Tomato industrial
96
9.4
43.4
dehydrated residues
-~
*dry
matter (DM),
crude protein
(CPI,
crude
fiber (CF), dry matter
digestibility (DMD), calcium (Ca), phosphore
(P)I
cuivre
(CU) et zinc
W-0 .
Source: Blancou et Calvet, 1977; Fall et al., 1987; Cissé et al., 1995a;
Cissé et al.,
1996b;
Gongnet et al., 1995; Richard, unpublished data;
Cissé, unpublished data.
Table 5: Inventory of main agricultural by-products research undertaken in
Senegal during the period 1969-1995.
Main agricultural
by-product
References
Rice straw
Calvet et Valenza, 1973
Calvet et al., 1974ab
Sali, 1984
Fall et al., 1989
Lemal et al., 1989
Richard et al., 1989
Steyaert et al., 1989a
Gongnet et al., 1996
Millet straw
Richard et al., 1989
Cissé et al., 1995a
Sorgho straw
Richard et al., 1989
Steyaert et al., 1989
Cissé et al., 1995a
Natural pasture straw
Buldgen et al., 1992
Buldgen et al., 1993
Cissé et al., 1995a
Groundnut husk
Calvet et al., 1969
Boudergues et Calvet, 1970
Calvet et Denis, 1974
Calvet, 1977
Sali, 1987
Steyaert et al., 1989a
Cissé et al., 1994
Groundnut haulms
Richard et al., 1989
Cotton seed
Calvet et al., 1973
Fabre et al., 1973
Faye, 1993
______-___-__-___--_----------------- ---___--_---_.----------~--------~-~-
a
: - .y., ‘.., ; .j
.I..‘..‘. :.
., \\,y ,. <::::. . ..‘.r.
.:...: ST
, 0, ,‘i - “.-.i;
K
Figure 1 - J.Ir:.I:-ibution of main crops 2nd brenA’
..,mg systems in Senegal (Richrd et as 1989)
“CROP RESIDUES IN SUSTAINABLE MIXED CROP/LIVESTOCK
PARMING
SYSTEIUS
Organized by ICRISAT (INTERNATIONAL CROPS RESEARCH INSTITUTE FOR
THE SEMI-ARID TROPICS), and held from April22 to 26, 1996, in Patancheru,
Asia.
USE OF CROP-RESIDUES IN THE AGRICULTURAL SYSTEMS OF SENEGAL.
A Country Report
Invitatimal paper
bY
Cissé Maimouna
Institut S&x?galais de Recherches Agricoles, BP 2057, Dakar
ABSTRACT
This study involved a survey of animal production systems and an inventory of trop by-
products available in the farming sector in Senegal. Cattle are the dominant class of
livestock, followed by sheep and goats, although both contribute to the cash economy. The
major factor affecting livestock production is feed shortage during the dry season.
Overgrazing leading to degeneration of vegetal caver, and the recent drought conditions,
have made the situation worse. Several trop residues and agro-industrial by-products were
identified as alternative feeds and potential supplements. The constraints associated with
their efficient use are emphasized. More collaborative research between NARS within the
eco-region and strengthened partnerships with IARCs are needed to make better use of these
feed resources for increased animal production of benefit to the population, without adverse
effects on the environment.
INTRODUCTION
Senegal is situated in West Africa, on the atlantic toast, in the intertropical
zone between latitude 12’30’and 16O30’N and longitude 11’30’ and I7O30’ W. It has a
land area of 196, 722 km2 and a population estimated at 8 million inhabitants. Two
ecological zones cari be distinguished according to rainfall pattems, the Sahelian zone in the
North and the Sudano-Guinean zone in the South of the country. Rainfall is unimodal,
occuring betwen July and September, and ranges in average Erom 200 mm in the North to
1500 mm in the Sou& This short rainy season is followed by a long dry season from
October to June during which rain never occurs.
The basis of Senegal economy is agriculture. Agriculture employs more than
70% of the population, accounts for 13 % of the Cross Domestic Product @DP), and makes
an important contribution to export earnings (Etude sectorielle de l’elevage, 1982). The
livestock sector, although characterised by low productivity, contributes to about 6.5% of
The cattle population increased by only 6% from 1970-1977 to 1990-1994,
while the sheep and goat numbers increased by over 44.7% during the same period (cattle
2462,000 in 1970-1977 to 2,612,OtXI in 1990-1994; sheep and goats 2647,000 in 1970 to
3,831,OOO in 1990) (Direction de l’Elevage, 1970-1994). This trend is also a result of the
actual increased pressure on land for cropping.
2. Role of livestock in major agricultural systems
Animal production involves both non-ruminants and ruminants, and a variety
of systems more or less integrated with crops (Table 2). Three major agricultural systems
closely related to agro-ecological zones have been identified:
.the pastoral system in the sylvo-pastoral zone in the North and East,
.the agro-pastoral system in the Centre and in the South,
.the peri-urban system.
-The pastoral system
The livestock management consists of a transhumant pastoralism practiced by
the Peuhl ethnie group whose major means of livelihood is almost exclusively cattle
production on extensive grazing land area (Diop, 1989). Household income and food supply
depend mainly on livestock.
Cattle are reared on natural pastures with sheep and/or goats and have to trek
great distances in search of fodder and water (Diop, 1987; Diop 1991). Nutrition is a major
limiting factor in pastoral systems. Availability and adequacy of feeds fluctuate with
seasons. Pasture productivity varies from 100 to 2,000 kg of dry matter per hectare from
year to year, and from 500 to 1,800 kg dry matter according to the types of pastures
(Boudet, 1984; Richard et al., 1989). Nutritional value of natural forage has been
extensively investigated in Casamance, in the South of the country (Boudet, 1970) and in
3. Impact of mechanization on the use of livestock in agricultural systems
In the Senegalese peanut basin, population growth and the extensive use of
animal traction have favored the excessive expansion of cultivated land to the detriment of
the pastoral land area. Traditional practices of maintaining soi1 fertility have been disturbed
by pastoral land restrictions (Faye, 1993). Pressure on land and the encroachement of
cropping lands on pastures has caused a reduction in the cattle population in the groundnut
bassin and a shifi to the use of cows for draught purposes. The use of horses and donkeys
for cropping and transport bas increased.
Agricultural production in the country has been better organised over the past
two decades and more and more development plans give priority to food production for
domestic use, with resultant increase in the agriculture-based industries.
With the decline and degradation of grazing lands through overgrazing and
the expansion of arable cropping, agricultural by-products take on greater significance. For
example, cotton production increased from 1,000 tons in 1987 (Plan d’Action pour
l’Elevage, 1988) to 50,000 tons in 1991-1992 (Direction de l’Agriculture, 1992).
Consequently, the use of cotton seed, a major protein source, greatly increased for beef and
sheep fattening in the Center and in the South of the country. In 1986, 887,820 tons of
maize, millet, sorghum and rice grain were harvested. The estimated straw output is
4,800,000 tons (Fall et al., 1989). An increase in available quantities of straws could be
expected with the development of irrigated cropping in the Senegal river valley and
mechanisation.
II. USE OF CROP RESIDUES AS LIVESTOCK FEED RESSOURCES
1. Farmer’s current practices on utilizing trop residues as a source of
livestock feed in major agricultural systems.
Quantitative estimates of trop residues are not usually reported in national
statitics. Groundnut and millet are the major crops in Senegal. Groundnut haulms are
therefore the most abundant trop residue (Table 3). Millet straws are second in importance.
There are widely used as animais feed. The other trop residues and agro-industrial by-
products (Table 2) include cereal and legume straws, wheatbran, dried brewers’grains
(spent grains from the breweries), oilseed cakes, cottonseed cake and palmkernel) and
cereal bran. Without the availability of trop residues, ruminants could hardly survive the
long dry season.
In years where statistical data on agro-industrial by-products have been
reported, large quantities are found. High quantities of them (groundnut cake, cotton seed,
pahnkernel cake, molassis) are however exported (Etude sectorielle de 1’6levage au Senegal,
1982).
3. Current practices used in processing trop residues
Cereal straws and groundnut haulms are scattered on the farms after
harvesting the grains. Sorghum stalks retain a better quality if harvested early, dried and
stored off the ground on man made storage facilities. Bundles of rice straw, weighing 10-13
kg, and groundnut haulms are marketed as animal. The main customers are transport
businesses with draft animals, and the peri-urban milk and meat producers.
Most of the groundnut grown in the country is locally processed into oil. The
remaining cake is a valuable source of energy and protein. The industrial cake is exported.
The domestic cake and cereal bran are the major by-products useful as animal feed which
are produced at the village level. There is a certain import of wheat processed locally into
flour. However, the quantity of wheat bran appears to be limited.
Cereal trop residues are important feed resources in the mixed farming
systems. However these residues are high in lignocellulose compounds and are
characterized by low protein content, and low digestibility and voluntary intake (Sall, 1984;
Fall et al., 1989). When fed alone to ruminants, as practiced by several farmers, they cari
not support maintenance requirements.
A great deal of research on forages has been done in various research centres
and feeding recommandations were formulated for farmers. Improvement in the nutritional
value of straws with physical treatments and supplementation with other by-products (Table
S), and good animal performances were reported with on station-research. Chemical
treatment of straws (Blancou and Calvet, 1977) is restricted by COS, technical ability and
safety. However, urea seems promising (Fall et al., 1989; Cisse et al., 1995b, 1996a;
Gongnet et al., 1996), because it is cheap and easy to obtain at the village level. The
evaluation of its profitability at the farm level is going on in the Senegal valley river with
rice straw and in the peanut basin, in the Center, with natural pasture straw.
4. Current practices used to supplement trop residues
In the agropastoral system, farmers commonly use trop residues
supplemented with artisanal groundnut cake, and cotton seed, or they cari mix various trop
residues for animal feeding.
In the agricultural areas, farmers generally waste feed resources and
consequently animals are over or underfed. There is an often ineffective coliection of the
groundnut haulms which is by far the most important and the best quality feed for animals.
If they still contain many leaves, groundnut haulms cari support daily gains of 0.5 kg
liveweight for thin cattle afier a dearth period. Millet, maize and sorghum straws represent
30 to 50% of the cattle diet during the dry season and a smaller part of the small ruminant’s
diet, in agro-pastoral zones (Richard et al., 1989).
Many years of research on the nutritive value of every type of trop residue in
several combinations showed technical advantages of using these resources (Table 5) as
animal feed. The technologies generated (diets formulated with many agro-industrial by-
products) without economic analysis are beyond the reach of farmers. Research on both
pasture and agricultural by-products has had a very limited impact on livestock productivity
in the small-scale farming systems.
5. Major constraints on utilization of crops residues as livestock feed
The major constraints associated with the use of by-products are their
bulkiness, transportation, storage and processing.
After harvesting the grains, cereal straws have to be bulked and transported
to the villages and stored. The fnst problem encountered is transport both on farm and on a
regional basis where by-products may be located in a different area to livestock.
The second problem is the amount of labour required to collect and store the
trop residues. People are busy harvesting crops and do not take time to collect and store the
trop residues (Fall, 1986). Another constraint is the actual manner of storage, whether on
platforms, in the field, fenced, etc...Moreover, there are no machines in the villages to
process these straws for incorporation in diets for ruminants. In the harvesting process,
development of simple machinery such as choppers or chaffcutters would be benefïcial in
reducing by-product particle size.
Inadequate and inefficient use of the available technology is also a major
limitation to increased animal production.
6. Nutritive value of trop residues
An important study was carried out to determine the nutritive value of (1)
native herbages of natural pastures in the Sahelo-sudanian zone, (2) fodder grasses
cultivated under irrigation and (3) some trop residues and agro-industrial by-products
(groundnut haulms and cake and cereals straws) encountered in Senegal. The determination
of their chemical composition (Table 3), digestibility and feeding triais results allowed the
establishment of Feed Tables (Richard et al., 1989). However, other studies are needed to
specify the feeding value of each by-product with high potential.
The feeding values of millet, maize and sorghum straws are very low. Their
dry matter digestibility ranged from 42.8 to 49% (Sall, 1984, Fall et al., 1989, Gongnet et
al., 1996) and their organic matter digestibility depends on the leaf/stem ratio (0.2-0.35),
and ranges from 40-45% for the entire straws and from 50-55% for the leaves. Rice straw
has a higher organic matter digestibility (56%) (Richard et al., 1989) than the other straws.
The energy content of groundnut haulms varies between 0.50 to 0.72 UFL/kg
DM and their digestible protein content between 40 to 74/kg DM, depending on the
leaflstem ratio (0.2 to 1.5 according to harvesting practices) (Richard et al., 1989). Rice
bran has a chemical and a nutritive value negatively affected by high levels of silica (12.2%
DM) and ADL (8.2% DM), as a consequence of a high proportion of hulls.
Most of the forages have insufficient mineral content (P, Ca, Na, CU and Zn) to
meet the requirements of livestock (Cissé, 1985; Guérin et al., 1989; Cisse et al., 1996b).
Some trace elements content such as CU and Zn are, in most of the forages, under the limit
of deficiency .
Studies on the toxicity of trop residues (gossipol content of cotton seed, and
other toxic constituer@ like alkaloïds, glucosides, polyphenols, hydrocyanic acid, oxalic
acid, etc...) are very scarce. However, detoxification of groundnut cake against aflatoxine
is required for EU exports.
7. Opportunities for collaborative research on strategies for using trop
residues as animaf feeds.
Feed is the principal constraint among the non genetic factors affecting
animal production, particularly during the dry season. Fodder is of poor nutritional value
for most of the year due to the rainfall pattern, and trop residues and other feed resources
are greatly underused. This situation Will be worsened if livestock productivity and
population increase. However, there is an immense potential for improving animal nutrition
and therefore production by using trop by-products. The use of farm-produced by-products
(stovers, straws, bean and groundnut haulms and household offals) and agro-industrial by-
products as animal feed is an efficient and ecologically sound use of feed resources.
Attention must be given to research on forage production and agricultural by-
products which are an important feed resource in animal production systems. Increased
intensification and efficiency in the use of feeds is most important and emphasis should be
given to feeds that do not compete with human food.
In the sylvo-pastoral area where the production system is pastoral, increased
fodder production Will be possible with the rehabilitation project to improve water
availability in fossiled valleys, as are corrections of minera1 deficiencies. Adapted forage
cari provide nutrients for ruminants. More productive and high yielding forage crops need
research. The agronomie characteristics of these forages need to be determined in order to
achieve maximum bene& from them. Fertiliser requirements, frequency of cutting, cutting
height, grassllegume mixtures and other factors affect the yield and nutritional value of
forages.
availability of support services and infrastructure that producers need in order to make best
uses of by-products.
Government policy should promote the optimal use of the local feed
resources in the animal industry and improve the capacity of the private sector capacity to
respond to the market environment. With the devaluation of the CFA franc by 50% in
February 1994, exports of agro-industrial by-products increased.
9. The institutions involved in research and development of livestock feed
based on trop residues: their spcciality and liukages with advanced institutions in
developed countries and with IARCs.
In the recent past, some international institutions such as FAO, CIRAD, ILRI
through AFRNET and IDRC have funded research projects on the use of by-products, in
Senegal .
Factors limiting the utilisation of technical packages at the small-holder level
include poor coordination between research institutions and development organisations.
Researchers do not get enough feedback information to enable them to plan their research
activities based on the needs of farmers. SO, projects are usually proposed on their own
perceived problems.
In order to facilitate the immediate diffusion of technologies generated by the
scientists into the farming systems, a well-organised extension system is required. It is also
important to improve linkages between researchers and extension workers to share
experiences (through joint research propos&), and the extension services have to be
strengthened through training extension staff.
It is also important to note that, in Senegal as in several developing countries,
the level of research fùnding and the infrastructure in terms of laboratories and facilities and
trained manpower are limited. Partnerships between NARs, IARCs and other regional
institutions on common research needs on the use of trop residues has to be strengthened.
This cari be done through a better exchange of information, training, participation in
workshops and other scientific meetings.
Acknowledgments
1 wish to thank Drs Tom Cusac, Head of NRBAR/ISRA (USAID), Abdou Fall, Head of
ISRA/URA Productions Animales, and my colleague Cheikh M’Baye Boye for critically
reading the manuscript.
References
Adegbola A.A., Smith O.B., 1982. Use of pasture and agro-industrial by-products for
ruminant production in West Africa. FAO Animal Production and Health Paper, n032, 115
126.
Ba-Diao M., 1991. Les systèmes d’&levage dans la zone des Niayes au sénégal. 1.
L’t?levage traditionnel. Etudes et Documents, ISRA, vol. 14, 29p.
Blancou J., Calvet H., 1977. Fermentation microbienne de produits végétaux destines à
l’alimentation du bétail au Senégal. Physio-Nutrition, LNERV, ISRA, 15~.
BO Kohl, 1982. Les aliments du b&ail sous les tropiques. Données sommaires et valeurs
nutritives. Collection FAO, Production et sante animales, no 12.
Boudergues R., Calvet H., 1970. Note sur la digestibilittc des coques d’arachide utilisees en
alimentation animale. Rev. Elev. Med. Vét., Pays trop., 23, 493-502.
Boudet G., 1970. Pâturages naturels de Haute et Moyenne Casamance (Republique du
sénegal) , Etude Agrostologique, n ’ 27, IEMVT .
Buldgen A., Detimmerman F., Piraux M., Compère R. 1992a. Les techniques d’embouche
de moutons en région soudano-sahelienne sénégalaise. Rev. Elev. Med. vet. Pays trop., 45,
321-328.
Buldgen A., Detimmerman F., Sa11 B., Comp&re R. 1992b. Etude des param&res
demographiques et zootechniques de la poule locale du bassin arachidier sénégalais. Rev.
Elev. Med. vét. Pays trop., 45, 341-347.
Buldgen A., Lemal D., Steyaert P., 1990a. Engraissement de taurillons et de mâles de race
Gobra à partir de sous-produits agro-industriels melasses au Seriegal. Tropicultura, 8, 107-
111.
Buldgen A., Piraux M., Deletre J.L. et Compkre R., 1990b. Embouche de taurillons de
race Gobra en milieu villageois du bassin arachidier sénégalais. Bull. Rech. Agron.
Gembloux, 25, 251-262.
Buldgen A., Piraux M., Dieng A., Comp&e R. 1993. Mise au point de techniques
d’embouche bovine villageoise dans le bassin arachidier. WAWRMZ, 76, 27-34.
Calvet H. et Denis J.P., 1974. Embouche intensive du mouton peulh-peulh senegalais,
Physio-alimentation, LNERV, ISRA, 33~.
Calvet H., 1977. La coque d’arachide en alimentation animale. Physio-Nutrition, LNERV,
ISRA, sp.
Calvet H., 1979. Les sous-produits agro-industriels disponibles au Sénégal et leur utilisation
en embouche intensive. Actes des IX Journées Mklicales, 15-20 janvier 1979, 51~.
Calvet H., Boudergues R., Friot D., Valenza J., Dia110 S., Chambon J., 1974a. La paille
de riz dans l’alimentation animale au Sénégal: 2-Biochimie du rumen - Embouche intensive
- Conclusion. Rev. Elev. Med. Vet. Pays trop., 27, 347-362.
Calvet H., Valenza J., 1973. Embouche intensive de ~&US peuhl sénégalais à base de paille
de riz. Rev. Elev. Med. Vét. Pays trop., 26, 105-l 16.
Calvet H., Valenza J., Boudergues R., Dia110 S., Friot D., Chambon J., 1974b. La paille
de riz dans l’alimentation animale au Sénegal: l-Analyses bromatologiques-Digestibilite
in
tivo et in vitro. bilans azotes et minéraux. Rev. Elev. Med. Vét. Pays trop., 27, 207-220.
Calvet H., Valenza J., et Boudergues R., 1969. Coque d’arachide et alimentation du bétail.
Colloque sur l’élevage, Décembre 1969, Fort Lamy.
Calvet H., Valenza, Friot D., et Wane A.M., 1973. La graine de coton en embouche
intensive, Performances comparées des zébus, des taurins et des produits de leur
croisement. Rev. Elev. M&l. vét. Pays trop., 26, 349-362.
Cisd M., 1985. Etude des carences minérales au Sénégal: Exploitation des resultats acquis
pour l’ébauche d’une cartographie. Mémoire de confirmation. Réf. 75 Al.-Nutr.,
LNERV, ISRA, 12Op.
Cissé M., 1991. Situation actuelle de la production laitiere au Sertegal. LNERV, ISRA,
Dakar, 13~.
Ciss$ M., Awad M., Ahokpé B., 1993. Comportement alimentaire et performances laitières
des chèvres saheliennes exploitant des parcours naturels. In Proc. biennial Conf. African
Feed Res. Network, 6-10 Dec., Harare, Zimbabwe, in press.
Cisse M., Fall S.T., Ditaroh D., Korréa A., 1992. Changes in body condition of zebu
cattle according to the level of feeding. In Proc. Al1 Africa Conf. Anim. Agric., 23-27
Nov., Nairobi, Kenya.
Cisse M., Fall S.T., Korréa, 1995a. Une vue de l’évolution mensuelle de l’état corporel
des zébus Gobra au cours d’une op&ation d’embouche à base de sous-produits agro-
industriels. Fiches techniques ISRA, ~01.6, nOl, 18 p.
Cissé M., Fall A., Sow A.M., Gongnet P., Korrea A., 1995b. Effet du traitement de la
paille de brousse à l’urée et du niveau alimentaire sur les variations de poids vif et de notes
d’etat corporel des ovins saheliens en saison seche. Int. Symp. Nutr. Herbivores, Sept.95,
Montpellier, Ann. Zootech., in press.
Cissé M., Fall A., Sow A.M., Gongnet P., Korréa A., 1996a. Traitement de la paille de
brousse à l’urée 4% et utilisation pour l’entretien des animaux en saison Seche et pour
l’embouche. Fiches techniques ISRA, en cours d’edition.
Cissé M., Gu&in H., Prince E., 1996b. Les carences min&ales existent au Senegal.
Comment corriger ce deficit nutritionnel?. Notes et Document ISRA, ~01.6, n’3, 22~.
Cissé M. Ly I., Manga R., 1995~. Evaluation of body lipid change in the Sahel goat
according to the level of feeding by the condition scoring method. Int. Symp. Nutr.
Herbivores, Sept.95, Clermont-Ferrand, Ann. Zootech., 44, Suppl., 330.
Cissé M., Seck M., Ba-Diao M., Sane 1. 1996c. Effet de la somatotropine bovine sur les
quantites de lait recolte après tétee chez les vaches Djakore “Bos indicus x Bos taurus”, au
Senegal. An. Zootech., ~01.45, in press.
Denis J.P., Calvet H., Friot D., Vassiliades G., 1976. Embouche intensive du mouton
Touabire sénegalais. LNERV, ISRA, Dakar, 16~.
Denis J.P., et Valenza J., 1971. Exteriorisation des potentialités génétiques du zébu peuh1
senégalais (Gobra). Rev. Elev. Med. v& Pays trop., 24,409-418.
Denis J.P., Valenza J., et Thiongane P.I., 1972. Exteriorisation des potentialités du zébu
Gobra. Resultats des abattages pratiqués en 197 1. Rev. Elev. Med. vet. Pays trop., 25,
245-257.
Denis J-P., Valenza J., et Thiongane P.I., 1974. Extériorisation des potentialités du zébu
Gobra. Résultats des abattages pratiqués en 1972. Rev. Elev. Med. vét. Pays trop., 27,
109-l 14.
Dieng A., 1984. Utilisation des sous-produits agricoles et agro-industriels disponibles le
long du fleuve Sénegal. Th. Ingenieur Agronone, Fac. SC. Agr. Gembloux, Belgique.
Diop A.T., 1987. Les ressources de l’aire pastorale de Tatki. Inventaire et etude du mode
d’exploitation. Proposition de plan d’aménagement et de gestion rationnelle. Ref 17
Agrosto., LNERV, ISRA, 19Op.
Diop A.T., 199 1. La gestion des parcours de l’aire d’influente du forage de Tatki.
Relations entre données de vegetation, taux d’exploitation et transhumance. Réf. 5
Agrosto., LNERV, ISRA, 18~.
Diop M., 1989. Les systèmes d’elevage dans le Ferlo: &ude synthetique de la situation
actuelle. Séminaire FAPIS, 22-26 Mai 1989, Dakar.
Diop P. E. H., Cissé M., Sow A.M., 1992. Performances de reproduction et de production
laitière de la Jerseyaise au sénegal. In Proc. VII International Conference of Institutions
of Tropical Veterinary Medicine, Sept. 1992, Abidjan, Côte d’ivoire, 368-378.
Direction de 1’Elevage. Rapports annuels de 1970 à 1994. République du Sdnegal.
Direction de l’Agriculture, 1992. Rapport annuel des activités agricoles. Minist&re du
Développement Rural et de l’Hydraulique, République du Sénégal.
Direction de I’Elevage, 1992. Conseil Interminist&iel sur 1’Elevage. Minist&re du
Développement Rural et de I’Hydraulique, Republique du sénegal.
Etude sectorielle de l’élevage au Sénégal (Situation et perspectives), 1982. Etude Banque
Mondiale/FAO, Minist&re du Développement Rural, Dakar, S&régal, 3-46.
Fall A., 1986. Feasability evaluation for improved livestock sector for the agropastoral
production system of the Upper Casamance, Senegal. Th. Master of Science: Animal
Science, Michigan State University, USA.
Fall S.T., 1993. Valeur nutritive des fourrages ligneux, leur rôle dans la complementation
des fourrages pauvres des milieux tropicaux. Th. Doctorat Zootechnie, ENSA Montpellier,
139p.
Fall S.T., Cissé M., Richard D., Ditaroh., 1993. Production intensive de viande bovine au
Sénégal. Rapport de contrat ISRAKRDI, Res. Al/Nov. 1993, LNERV/ISRA, Dakar.
Fall S.T., G&in H., Sall C., et M’Baye N., 1989. Les pailles de c&?ales dans le systeme
d’alimentation des ruminants au Senegal. ISRA, vol 2, no 1, 38~.
Favre B., Calvet H., Valenza J., et Wane A.M., 1973. Nouvel essai d’embouche intensive
avec les sous-produits de l’industrie cotonnière. LNERV, ISRA, Dakar, 37~.
Faye A., 1993. Situation et perspectives de l’elevage bovin dans les systèmes agro-
pastoraux denses de la zone sahelo-soudanienne. Le cas du Sud du Bassin arachidier du
Seriegal. These doctorat en Sciences Agronomiques, ENSAM, Montpellier, France.
Faye A., Landais E., 1985. L’embouche bovine paysanne dans le Centre-Nord du bassin
arachidier au Sénegal. In: DSAKIRAD, Relations Agriculture-elevage, 304-311.
Faye M., 1981. Etude de la rentabilité de l’utilisation de rations à base de sous-produits
agricoles et agro-industriels en embouche bovine au Sénegal. Th. Doct. Med. Vét., n020,
EISMV, Dakar.
Gongnet G.P., Fadiga S., Cissé M., 1995. Amélioration de la valeur alimentaire de la
paille de riz par le traitement à l’ur& et la complémentation en cereales chez le mouton
Peulh skrégalais. Soumis pour publication.
Gu&in H., 1987. Alimentation des ruminants domestiques sur pâturages naturels sahéliens
et sahelo-soudaniens. Etude methodologique dans la région du fer10 au Sénégal. Th.
Doctorat Ingénieur, spkcialite Agronomique, ENSA, Montpellier, 21 lp.
Gu&in H., Cissé M., Heinis V., 1989. Composition minkale des fourrages. In Elevage et
potentialités
pastorales
saheliennes.
Syntheses
cartographiques:
Senégal,
CTA/IEMVT/ISRA, P 8.
G~&in H., Friot D., M’Baye Nd., Richard D., Dieng A., 1988. Régime alimentaire de
ruminants domestiques (bovins, ovins, caprins) exploitant des parcours naturels saheliens et
soudano-saheliens. II. Essai de description du régime par l’étude du comportement
alimentaire. Facteurs de variation des choix alimentaires et consequences nutritionnelles.
Rev. Elev. Med. vet. Pays trop., 41,427-440.
Gueye 1.S et N’Diaye A.L., 1979. L’utilisation des produits et sous-produits agroindustriels
en elevage. Aspects economiques. In Actes des IXbmes Joumees Médicales, 15-20 janvier
1979, 51p.
Kane B., et N’Diaye M., 1982. Utilisation des sous-produits agricoles et agro-industriels
dans l’alimentation du bétail au Sénégal. Production et Santé animales, Rome FAO, no 32,
136~.
Lemal A., Faye J-C., Buldgen A., Compkre R., 1989. Influence de la proportion de
melasse liquide sur la valeur alimentaire des rations pour ruminants composées des sous-
produits disponibles dans la val& du fleuve Sénegal. Bull. Rech. Agron. Gembloux, 24,
315-328.
Lhoste P., 1987. L’association agriculture-elevage. Evolution du système agropastoral au
Sine-saloum (S&égal). Maisons-Alfort, IEMVT, 1987, 314~. (Etudes et syntheses de
I’IEMVT n”21).
Ly C., 1989. La politique de développement de l’dlevage au Senegal: Repères sur
l’evolution, les réalit& et les perspectives de l’elevage des bovins et petits ruminants, 1960-
1986, n’l, ISRA/CRDI, 62~.
M’Baye M., 1988. Les productions bovines au Sertegal. In Actes de l’atelier du CIPEA sur
les Recherches en Productions bovines associees lait-viande en Afrique de I’Guest, Ibadan,
24-27 Octobre 1988, Nigeria.
Plan d’Action pour l’élevage,
1988. Ministère du Développement Rural et de
l’Hydraulique, République du Senegal, 76~.
Richard D., Guérin H., Fall S., 1989. Feeds of tbe dry tropics (Sénégal). In: Ruminant
Nutrition, R. Jarrige Ed., Paris, France, INRA and John Libbey Eurotext, p.325342.
Sall B., 1987. Comparaison de l’utilisation par les bovins et par les ovins d’aliments
fabriques à partir de sous-produits disponibles au Senegal. Th. Doctorat v&%inaire, no 1,
EISMV, Dakar.
Sali C., 1984. Complémentation de la paille de riz en fonction des objectifs de production:
choix d’une complémentation azotée, choix d’une complementation énergetique.
LNERWSRA, Dakar, 14~.
Seck P.A., 199 1. Progres techniques et satisfaction des besoins légumiers dakarois.
Réflexions et Perspectives, ISRA, vol. 2, no 1, 33~.
Sow A., 1991. Contribution à l’&ude des performances de reproduction et de production
laitière de la jersiaise importe% au Sénégal: Exp&ience de la SGCA. These de Doctorat
v&%naire, no 13-, EISMV, Dakar.
Steyaert P., Buldgen A., Compere R., 1989. Embouche intensive des taurillons de race
Gobra à l’aide de sous-produits agricoles en provenance de la val& du fleuve Sénégal ou
d’ensilage de mil complément& Bull. Rech. Agron. Gembloux, 24,297-313.
Table 1: Trends in livestock species in the last two decades (Direction de
l'élevage, rapports annuels 1970-1994)
____________-_-----_------------------------------------------------------
Livestock
Population (,OOO)
B change
species
_------------_---------~-
over the period
1970/77
1983/89
(1970-1989)
____-_------~_------~-~~~---~-~~~~~~~~~~~~-~~~~-~----~~-~-~~~~~~~~~~~~~~~~
Cattle
2462
2397
-3
Sheep & goat
2647
4471
+69
Pigs
256
204
-26
Horse
209
289
i-38
Came1
7
9
+43
Poultry
10500
____________-__-_-_-------------------------------------------------------
Table 2: Major agricultural systems in different agro-ecological zones in
Senegal
_ _ ________________---_------------------------------------------------
Agro-ecological
Major agricultural
Main Livestock Predominant Feeding
Zone
sys tems
Products
System
_________----__-----------------------------------------------------------
Sahelian
Goats/cattle/sheep
meat
Pasture grazing
(ZOO-5OOmm)
Rice, sugar-cane
milk
By-products
vegetables:tomatoes,
onions, beans, cassava
fruit: water melons
Sahelo-soudanian
Cattle/sheep/goats
meat
Pasture grazing
(500-7OOmm)
groundnut, millet
milk
Groundnut haulms
sorghum, maize
Cereal straws
Vegetables: tomatoes,
Commercial concen-
potatoes, beans carrot,
trate
cassava and fruits: mangoes,
oranges
Soudano-sahelian
Cattle/sheep/goats
meat
Pasture grazing
(700-9OOmm)
Groundnut, millet
milk
Groundnut haulms
sorghum, maize, cotton
Cereal straws
Cotton seed
Soudanian
(900-12OOmm)
Cattle/sheep/goats
Meat
Pasture grazing
Cotton, Groundnut
Groundnut haulms
millet,sorghum, maize,
Cotton seed
Cereal straws
Soudano-guinean
Cattle/goat/sheep
Meat
Pasture grazing
(1200-18OOmm)
Rice, groundnut
trop residues
millet, sorghum, palm-
Browsing tree-
trees, vegetables: beans,
foliages
cassava, fruits: banana
mangoes, oranges
----_-----------
________-_-----_-__---~-----~--~-~--------------------~
Table 3:
Agricultural
and
agro-industrial
by-product feed resources
available in Senegal
Feeds
Quantities (tons)
References"
Rice straw
170,000
Maize straw
102,633
Millet straw
592,505
Sorgho straw
78,094
Groundnut haulms
1,500,000
Bean haulms
Wheat bran
20,000
Rice bran
10,000
Millet bran
Wet brewers'grain
1,000
4
Groundnut husk
Cotton seed
50,000
3
Tomato industrial
dehydrated residues
Groundnut cake
100 à 300,000
Cotton seed cake
5,000
Cotton seed husk
8,800
Palmkernel oil cake
4,000
Molassis
30,000
Bagasse
300,000
*l.Etude sectorielle de l'élevage au Sénégal, 1982
2.Plan d'Action pour l'élevage, 1988
3.Direction de l'Agriculture, 1992
4.Direction de lIElevage, 1992.
Table 4: Nutritive value of some agro-industrial by-products available in
Senegal
Constituents*
_________--_----- ___________-_- ---_--_-_-_-_-----
Crop residues
DM%
CP% CF%
DMD Ca
P
CU Zn
-_--w-m -______-_- ---
-__----
-___________
(on a dry matter basis) %
g/kg DM
(mg/@' DM)
Rice straw
92.3
23
34.5 42.8
1.7
5.8 44
(Oryza sativa)
Millet straw
85
56
41.4
39.2
1.6 2.3
4.0 14.7
(Pennisetum americanum)
Sorghum straw
77.4
39
40.3
47.2
-41
.43
17.9 76.5
(Sorghum bicolor)
Maize straw
86
38
38.6 49.3
2.0 1.5
(Zea mays)
Bean haulms
89.3
13 29
1.35 0.29
(Phaseolus sp.)
Groundnut haulms
87.2
10.7
34.2
54.8
9.2 1.2
5.6 19
(Arachis hypogea)
Natural pasture straw
Groundnut husks
98.6
61
34.8
18.4
0.6 0.4
Millet bran
83.9
13.9 20
1.1 5.1
Rice bran
93.3
51
76
0.8 3.4
Cottonseed
86.6
20.6 33.0
Cottonseed husk
93.2
70
48.9
1.3
1.4
Cottonseed cake
92.3
10.3
30.6
1.5 12.7
Molassis
10
56
0
7.3
0.7
Maize bran
90.4
9.8 8.9
;.2 04
4.6
.14
Groundnut cake
97.8
48.5 50
Wet brewers'grain
22.9
5.0 4.6
Tomato industrial
96
9.4
43.4
dehydrated residues
-~
*dry
matter (DM),
crude protein
(CPI,
crude
fiber (CF), dry matter
digestibility (DMD), calcium (Ca), phosphore
(P)I
cuivre
(CU) et zinc
W-0 .
Source: Blancou et Calvet, 1977; Fall et al., 1987; Cissé et al., 1995a;
Cissé et al.,
1996b;
Gongnet et al., 1995; Richard, unpublished data;
Cissé, unpublished data.
Table 5: Inventory of main agricultural by-products research undertaken in
Senegal during the period 1969-1995.
Main agricultural
by-product
References
Rice straw
Calvet et Valenza, 1973
Calvet et al., 1974ab
Sali, 1984
Fall et al., 1989
Lemal et al., 1989
Richard et al., 1989
Steyaert et al., 1989a
Gongnet et al., 1996
Millet straw
Richard et al., 1989
Cissé et al., 1995a
Sorgho straw
Richard et al., 1989
Steyaert et al., 1989
Cissé et al., 1995a
Natural pasture straw
Buldgen et al., 1992
Buldgen et al., 1993
Cissé et al., 1995a
Groundnut husk
Calvet et al., 1969
Boudergues et Calvet, 1970
Calvet et Denis, 1974
Calvet, 1977
Sali, 1987
Steyaert et al., 1989a
Cissé et al., 1994
Groundnut haulms
Richard et al., 1989
Cotton seed
Calvet et al., 1973
Fabre et al., 1973
Faye, 1993
______-___-__-___--_----------------- ---___--_---_.----------~--------~-~-
a
: - .y., ‘.., ; .j
.I..‘..‘. :.
., \\,y ,. <::::. . ..‘.r.
.:...: ST
, 0, ,‘i - “.-.i;
K
Figure 1 - J.Ir:.I:-ibution of main crops 2nd brenA’
..,mg systems in Senegal (Richrd et as 1989)