This study aimed to improve the information base on livestock production in sub-Saharan Africa by compiling and reviewing quantitative data on various aspects of ruminant production systems and estimating the offtake from these systems and their contribution to the supply of livestock products for human consumption. Emphasis was placed on quantitative information as this is a prerequisite for identifying opportunities for improvements and the likely effect of these improvements on the overall availability of animal food products. However, in sub-Saharan Africa such information is often fragmented and not easily accessible, although it is essential for effective livestock development planning.
Cattle and small ruminants comprise 72 percent and 16 percent of the total TLUs in sub-Saharan Africa. The study therefore focused on the region’s ruminant production systems, which were divided into two major categories: traditional and non-traditional, the main differences between the two being the production objectives, level of intensification and resulting productivity. In general, traditional systems are much more common than non-traditional systems. Within the traditional sector, ruminant livestock are kept in different production systems, which largely reflect differences in constraints, resource endowments and the potential for growth and development.
Four main criteria were used to further classify ruminant production systems: rainfall, LGP, cropping pattern and mean temperature during the growing period. These criteria have a particular advantage in that they convey information about the system’s resource endowment and hence its potential for improvement and growth:
Traditional systems were divided into pastoral/agropastoral systems and mixed systems. Mixed systems were further subdivided into tropical lowland (semi-arid, subhumid and humid) mixed systems and tropical highland mixed systems.
Cattle, sheep and goats are kept in varying proportions in all the systems identified, their relative distribution being determined by the comparative advantages of each species within the different zones.
In terms of total TLUs, 24 percent, 29 percent, 21 percent, 7 percent and 19 percent of the ruminant livestock are located in the arid, semi-arid, subhumid, humid and highland zones respectively.
For cattle, the study estimated that 21 percent, 30 percent, 22 percent, 4 percent, 20 percent and 4 percent of the population are contained in the pastoral, semi-arid, subhumid, humid and highland mixed and smallholder dairy systems respectively.
Non-traditional systems comprise ranching and dairy systems, the latter being subdivided into large-scale and smallholder dairy.
The criteria used to classify the systems also define the functions and the relative importance of livestock in each system:
Pastoral systems are defined as systems occurring in areas with an LGP of less than 180 days, where the grazing of ruminants is the predominant form of land use. Pastoral and agropastoral systems account for approximately 24 percent of the total ruminant TLUs in sub-Saharan Africa. Pastoralism (nomadic and transhumant) occurs where rainfall ranges from 0 to 400 mm per year and there is no cropping, whereas agropastoralism occurs where rainfall ranges from 400 to 600 mm per year. Livestock are the main source of subsistence and contribute between 49 percent and 100 percent to household income, with the contribution of crops being practically zero. The management of livestock in pastoral and agropastoral systems is aimed at ensuring subsistence, averting risk and adapting to the institutional environment, which consists mainly of communal grazing. Pastoral systems are characterized by relatively large herd or flock sizes, a high proportion of females (around 60 percent for cattle and around 70 percent for small ruminants) and, in the case of cattle, more steers than oxen.
Mixed systems in the semi-arid, subhumid and humid zones account for around 55 percent of the total ruminant TLUs in sub-Saharan Africa. Within the tropical lowlands, mixed systems can be differentiated on the basis of four criteria: agroclimatic conditions, human population density, tsetse challenge and livestock density. In general, tropical lowland mixed systems are characterized by varying degrees of interaction between the crop and livestock components, this being closely related to the input and output functions of livestock. Although livestock provide additional income (contributing between 5 and 20 percent to household income), rainfed agriculture is the main source of income and subsistence. Cattle-keeping for sale is usually less important than for draught power, security and the accumulation of assets. Herd sizes are usually smaller than in pastoral systems and the herd structure is characterized by a higher proportion of oxen (19 to 22 percent). Livestock are usually sedentary and, if movement is part of management, it is restricted to short distances.
Livestock in the highlands account for approximately 19 percent of the total ruminant TLUs in sub-Saharan Africa, and are principally located in East Africa. The largest area of highlands is in Ethiopia, where the system is largely a traditional one. This system has the highest level of crop-livestock integration found in sub-Saharan Africa. The contribution of livestock to household income lies between 82 percent and 96 percent when only farm sources of income are considered and is between 61 percent and 70 percent when non-farm sources are included. Cattle herd structures are characterized by a high proportion of oxen (20 to 30 percent), with an average household keeping two oxen, a clear indication of the importance of draught power. This system has the highest rate of utilization of draught oxen of any in sub-Saharan Africa. The various species kept by farmers are grazed on both private and communal pastures.
The non-traditional systems, comprising ranching and dairying, are found in almost every zone. Smallholder dairy systems occur mainly in the high-potential highland areas of Kenya and, to a lesser extent, in other East African highlands. Typically, the farmers grow crops and keep two or three dairy cows. In these systems milk for sale accounts for a higher proportion of income from livestock than in the traditional mixed highland systems, where the sale of cattle is the major source of livestock income. In general, land tenure is private rather than communal.
The study reviewed and analysed the production parameters of ruminant production systems in sub-Saharan Africa, as recorded in the literature. The following points concerning the measurement and study of production parameters in sub-Saharan Africa should be made:
There is inconsistency in the number and type of the production parameters recorded in the literature. This may be attributed to the differing objectives of the studies reviewed. The most commonly reported production parameters are mortality risks in young stock, milk offtake, calving/lambing/kidding rates and prolificacy. The length of productive life is hardly ever reported, although this parameter is very important in determining herd dynamics.
The literature survey also revealed inconsistencies in the measurement, definition and reporting of production parameters - for example, whether a parameter is a true rate, a risk rate or simply a proportion.
Various research protocols have been used to obtain information on production parameters. These range from longitudinal studies with follow-up, through cross-sectional studies, to retrospective cross-sectional surveys based on the recall of events by farmers. The periods covered also vary.
There are also variations in the criteria used to select study areas.
To improve the study of livestock production parameters, research protocols should be standardized. They should also take into account the dynamic nature of livestock systems, paying special attention to the parameters that affect herd dynamics, such as years animals are kept in the herd, age at first calving and mortality in different age groups.
In general, the production parameters reported in the literature show that:
Non-traditional grassland-based systems (i.e. ranching) achieve superior production parameters to traditional grassland-based (pastoral) systems, while smallholder dairy systems have higher productivity than traditional mixed systems. The production parameters of traditional ruminant production systems in sub-Saharan Africa are not only poor, but also show no marked differences between the different zones, systems and subregions. Mortality risks are high, especially among young stock (22 percent mean calf mortality risks, 27 percent mean lamb mortality risks and 28 percent mean kid mortality risks), calving rates are low, with a mean of 59 percent, while median milk offtake per lactation ranges between 200 kg and 300 kg.
The reasonably high reproductive performance of small ruminants is often countered by the extremely high young mortality risk. Nonetheless, estimated population growth rates are between 0.7 percent and 5.7 percent for sheep and between 2.3 percent and 12.5 percent for goats.
Cattle offtake rates are around 10 percent and appear to be slightly higher in pastoral systems than in mixed systems. Offtake rates of small ruminants are twice that of cattle, being 20.4 percent for sheep and 21.4 percent for goats, reflecting the higher reproductive capacity of these species and their importance as sources of income.
The clear difference in production parameters between traditional and non-traditional systems demonstrates the benefits to be gained by improving nutrition, management and health in the traditional sector. Contrary to expectation, differences within the traditional systems, where they exist, are not marked even though feed resources and other factors may be quite different. This may partly be explained by the fact that traditional systems are generally low-input and low-output systems, in which producers adapt to changes in the availability of feed resources by reducing or raising their stocking rates.
Modelling with LDPS2 and subsequent use of GIS have provided the following insights into the quantitative aspects of ruminant production systems in sub-Saharan Africa:
Livestock populations in pastoral systems are growing at a slower rate than in any other traditional system, with the semi-arid, subhumid and humid mixed systems showing the highest growth potential. In cattle, the extremely low growth rates noted in highland mixed systems may be partly due to the very low fertility rates reported for these systems.
Beef and milk offtake per animal per year are extremely low in traditional systems when compared with non-traditional systems. For example, beef and milk offtake per animal in traditional highland mixed systems is 6.8 kg and 24.8 kg per year, compared with 18.3 kg and 599.8 kg per year in smallholder dairy systems found in the same zone.
In terms of the distribution of beef and milk offtake, pastoral, semi-arid and subhumid systems together account for 77 percent of the beef offtake in sub-Saharan Africa, while 43 percent of the region’s milk offtake is produced in smallholder dairy systems, which account for only 4 percent or so of the cattle population.
The use of spatial analysis to depict the regional availability of meat and milk per person shows that per capita beef and milk supply are highest in subregions with smallholder dairy systems and lowest in the humid zones of Central and West Africa.
The combined use of livestock production modelling and GIS has potential as a tool in the quantitative characterization of livestock production and in subsequent planning for livestock development. However, the accuracy of the estimates of production and offtake used in such applications hinge on that of the underlying livestock density maps and of the classification of production systems.
The availability of more accurate livestock density maps covering the different species, together with the more accurate measurement of livestock production parameters, would greatly enhance the potential applications of the approach presented in this study. These applications include:
estimation of offtake of livestock products from the various livestock systems at regional, national or subnational level, allowing quantification of the contribution of each system to the availability of food of animal origin;
study of the development of the livestock sector (how livestock numbers and products from different systems change over time) and identification of constraints to the expansion and development of various production systems; and
quantitative ex ante impact assessment which would show how livestock development interventions, such as improved disease control or reproductive management, could improve productivity and farmer income, leading to identification of the institutions required to realize the potential for development.
