forage and animal feed production in Sudan
1.0 Introduction
The potentially arable land of Sudan amounts to about 200 million acre, only 20 % of which is exploited. Sudan has three major crop production systems: irrigated, rain-fed semi-mechanized and rain-fed traditional systems. Historically, the irrigated system is the pillar of the Sudan’s strategy for agricultural development representing the largest irrigated area in sub-Saharan Africa (4.8 million acre). It composed of large-scale Nile-based irrigation schemes in the Gezira, Kasala, Sinnar, White Nile, River Nile, Khartoum and Northern States. The rain-fed semi mechanized farming system extends to about 14 million acre in El Gadaref, Blue Nile, Sinnar and Southern Kordofan. The rain-fed, traditional system (the main subsistence system) accounts for 22 million acre, mostly in Kordofan, Darfur, Blue and White Nile States. The area under forage crops is mostly confined to the irrigated sector amounting to about 773 thousand acre representing 16% and 2% of the area under irrigation and the total are cropped, respectively.
Sudan is endowed with huge animal wealth ranking first in the Arab World and second in Africa. Based on the statistics of the Ministry of Animal Wealth, the national herd amounted to about 110 million head in 2021 (= 45.7 tropical animal unit) requiring around 130 million tons of dry matter feed per year, 70% of which comes from the natural vegetation as major source of feed. The natural pasture, being largely affected by a long dry period, supports only reproduction and maintenance requirements with little or no impact on improving animal performance in terms of productivity and quality.
Despite the low contribution of cultivated forages in maintaining the national herd, its role is however, maximized by the high quality value of green forages as compared to natural pasture and crop residues. Cultivated forages play a unique role in upgrading and finishing animals for export.
The sharp increase in the demand for animal products in urbanized and semi-urbanized centers, in addition to the growing market of forage export to the Gulf States have boosted production of cultivated forages the Sudan.
2.0 Forage production in Sudan
Cultivated forage crops in Sudan are produced under irrigation in two distinct sectors, namely, the traditional and the mechanized modern sectors. The latter sector which is exclusively devoted to exports, started in 2001 when the Gulf States decided gradual stoppage of forage cultivation and importation of their needs from abroad. In 2020, Sudan exported 584,000 metric tons (= USD 113 million). Both traditional and the modern sectors equally shared the area under cultivated forages in Sudan. The salient features of the two sectors are illustrated in the below table:
|
Feature |
Traditional sector |
Mechanized modern sector |
|
Variety |
Local alfalfa, forage sorghums |
Exotic alfalfa, Rhodes grass |
|
Cultural practices |
Manual (labor-intensive) |
Fully mechanized |
|
Irrigation method |
Surface irrigation |
Center Pivot |
|
Water source |
Mostly from the Nile |
Mostly from artisan wells |
|
Soil |
Fertile soils along the Nile |
Mostly poor desert soils |
|
Costs of production |
Low |
Very high capital costs |
|
Market |
Local market |
Export |
Being mainly produced as low input-cash crops, forages in the traditional sector favor high yields at the expense of the nutritive value. Recently, with the increased attention given to dairy and fattening schemes, a tendency towards high quality forage types started to emerge to maximize productivity of milk and live-weight gain. Under such conditions, the crop is mostly produced rather than purchased from the market and the producer has a chance to appreciate the validity of high quality forage.
Forage crops are either grazed, produced as green chop, hay or silage. The green chop (cut-and-carry) system is dominating in Sudan. This system has been able in the past to fulfil the need for animal feed; nowadays, in view of the rapid pace towards urbanization, it is no longer capable of meeting the huge demand for feed as it doesn’t allow employing modern means of production that facilitate wide scale production, storage and marketing of quality forage. Hay making, which may partially mitigate the weaknesses of green chopping system is restricted to export. Apart from the export-rejected hay, no locally produced hay is marketed in Sudan. Grazing and silage systems are not widely adopted in Sudan. Driven by the high demand for silage in Gulf States (860, 000 tons), production of more than 30,000 tons of corn baled-silage have been attempted by some pioneer producers in the River Nile and Khartoum States, however, such attempts declined due to transportation and handling difficulties.
3.1 The major forage crops grown in Sudan
3.1.1 Forage sorghum (Sorghum bicolor L. Moench)
Forage sorghums are the most important irrigated forage types in the Sudan. A part from the natural vegetation, the sorghum stover constitutes the bulk of the animal feed in the country (Bacon, 1948). Area wise, the traditional forage sorghum cultivar ‘Abu Sab’in’ is most widely grown covering about 350000 acre. In 2004 an improved version of Abu Sab’in (under the name Kambal) has been released as the first locally developed cultivar in the Sudan (Maarouf et al 2008). Sudan-1 is another forage sorghum cultivar released in 2009 selected from land-race ‘Garawi’ (sudangrass) (Maarouf, 2010). The first locally developed forage sorghum hybrid was released in 2010 (Maarouf, 2010). A number of exotic forage sorghum hybrids were also released during the last 3 decades. Forage sorghums are mainly grown for green chopping under the traditional sector and rarely made into hay or silage. They tolerate water stress and thrive under harsh conditions
3.1.2 Alfalfa / Lucerne (Medicago sativa L.)
Alfalfa is the most important leguminous forage crop in Sudan covering an area of 130,000 acre, most of which is confined to Khartoum, River Nile and Northern States. More than half of this area is grown by exotic varieties under mechanized farming for hay export. On the other hand the local variety Higazi represents the core of the traditional system. Unlike the exotic varieties, Hegazi has vigorous growth and erect-tall stature that allow for hand chopping. Our research results showed beyond doubt the superiority of the local variety Hegazi in forage yield over the exotic varieties. The outstanding performance of Higazi in the Sudan was reported to cause envy in Britain and the United States (Bacon, 1948) as yields greater by 5 to 6 folds were attainable. This is largely attributable to the adaptability of Higazi to the environment of production, specifically, the traditional green chopping system where the exotic materials failed to compete. Quality wise, the variety Hegazi performed very well in crude protein (approaching 27%) with satisfactory level for crude fiber (34%). A proposal for the release of the variety Higazi and 3 exotic alfalfa varieties has been submitted to the Variety Release Committee in October 2022 (Maarouf and Suad 2022). If accepted, this will be the first release of alfalfa varieties in Sudan
3.1.3 Rhodes grass (Chloris gayana Kunth)
The year 2012 marked the real takeoff for commercial Rhodes grass production in Sudan. The area covered with Rhodes grass in Sudan estimated to approach 80000 acre, placing it second to Alfalfa as perennial fodder crop. Rhodes grass is grown under the fully mechanized pivot irrigation utilizing water pumped from artesian wells. The crop is exclusively grown for export to the Gulf States where it can fetch high prices justifying the huge initial costs of the pivot system. Recently, a less expensive production system employing surface (border) irrigation has been attempted using Nile water. However, Rhodes cultivation under the small-scale traditional system is not feasible due to difficulties involved in manual harvesting. Compared to alfalfa, Rhodes grass is inferior in protein content but gives 3 times greater yield with lower water requirement. In September 2022 the Variety Release Committee released Finecut and Reclaimer as the first Rhodes grass varieties released for commercial production in Sudan (Maarouf et al. 2022).
3.1.4 Maize (Zea mays L)
In the Sudan, maize is grown mainly as feed crop (both forage and grain) and rarely as food crop. The area cropped to maize in the Sudan in 2014 was 126 thousand acre representing around 82% above that grown in 2013. This area is expected to increase considerably since the crop has recently received great attention as maize for silage and/or as grain feed for poultry industry. Unlike sorghum, maize is less tolerant to drought, salinity and water logging stresses, yet in Sudan, forage maize perform better than sorghum in winter sowings and has good reputation for milk production when fed as green forage. Many maize hybrids have been released in Sudan all of which are exotic varieties. Only two locally developed open pollinated varieties (Hudieba 2 and Hudieba1) have been released.
4.0 Other forages
These comprises: Clitoria (Clitoria ternatea), Lablab bean (Lablab purpureus L. Sweet), Cowpea (Vigna unguiculata L. Walp) and Phillipesara (Phaseolus trilobus Ait). Newly emerging promising forage crops include Panicum (Megathyrsus maximus (Jacq.) B.K. Simon & S.W.L. Jacobs) and Soybean (Glycine max. L). Clitoria is highly palatable and nutritious perennial forage legume that can last for many years. The other crops, apart from Panicum, are annual summer legumes rich in protein and can be grown for both forage and grain. Panicum is a high yielding perennial forage crop valued for milk production. Apart from soybean, no varieties have been released for these crops. For Soybean, 4 varieties from IITA (Institute of Tropical Agriculture, Nigeria) have been released, namely: TGx 1945-1F (Soy-Sudan-1), TGx 1954-1F (Soy-Sudan-2), TGx 1835-10E and Soya04.
5.0 Crop residues
Crop residues is one of the major source for inexpensive feed roughages in Sudan. About 75% of crop residues in Sudan comes from stovers of sorghum grown for grain production. Other important crop residues include maize stovers, wheat straw and legume haulms (mainly groundnuts). The crop residues in Sudan accounts to about 10 to 15 million tons depending on the area cultivated. Quality wise crop residues has low contribution to the feed value, however, their nutritive value could be enhanced by developing dual purpose (grain/forage) varieties. Presently, our efforts to develop dual sorghum varieties are at the national testing for release. Such varieties are having the potential of combining, to the maximum possible, improved feed and food attributes. Simultaneous improvement of sorghum for both fodder and grain attributes will help meeting the demand for both fodder and grain and allow maximum utilization of the limited farmer’s resources.
6.0 Concentrates
Industrial by-products of plant origin resulting from oil and milling industries are important source of animal feed rich in protein and energy i.e. cakes and meals of oil crops (groundnuts, sesame, sunflower, cottonseed) and bran of wheat and sorghum. Feed industry in Sudan could benefit from all of the above resource to process concentrates and other feed stuffs necessary for intensive production systems. Presently, the contribution of oil and milling industry to the animal feed is very low (1.6 million tons) considering the huge areas grown by oil and cereal crops in Sudan. Sudan imports its requirements from soybean meals (protein source) and maize (energy source) from abroad. Meals and cakes from locally produced oil crops could largely replace soybean imports, also, sorghum grain could replace that of maize. Feeds from by-products industry should be free from anti-nutritional factors (mycotoxines, pesticides residues etc..).
7.0 Forage industry in Sudan
More than half a century elapsed since the establishment of the first forage factory in Sudan (Abu Rannat) in the early 1960s. Forage industry has never witnessed significant development since that time. The contribution of the forage factories to the animal feed in Sudan is meagre not exceeding 215 thousand tons produced by 16 factories having production capacity of 345 thousand ton for all factories. This amount accounts for 0.2% of the total feed produced in Sudan.
