B.H. Ogwang
Faculty of Agriculture, University of Swaziland
P.O. Luyengo, Swaziland
Introduction
Pattern of pasture production in Swaziland
References
Swaziland has a total land area of 17,365 km² and is divided into four distinct topographical regions: the highveld, middleveld, lowveld and lumbombo, each running roughly north to south. Just over half of the country's area is vested in the King in trust for the Swazi nation and parts of it are allocated by chiefs to individual Swazi families. This sector is known as Swazi Nation Land (SNL). The agriculture in this sector is mainly subsistence in character.
The rest if the land is known as Individual Tenure Farms (ITF) and is owned on freehold or concessionary title. It includes commercial forests as well as farms, estates and ranches, and land owned by the Swaziland Government. The agriculture of the ITF is highly modernized and most of the country's cash production is derived from it.
Livestock have traditionally been an important component of the agricultural industry in Swaziland. Table 1 shows the population of ruminant livestock according to the most recent census.
Table 1. Ruminant livestock population in Swaziland
|
Class of livestock |
Total in country |
Number on SNL |
|
Cattle |
636,036 |
502,000 |
|
Goats |
320,398 |
286,000 |
|
Sheep |
40,138 |
26,000 |
|
Equines (mules, horses, donkeys) |
16,975 |
14,000 |
Source: CSO 1982
The majority of the herd is owned by the subsistence farmers in SNL (Table 2).
Table 2. Swaziland land-use figures for 1981/82 (hectares)
|
Land-use category |
Whole country |
SNL |
ITF |
|
Cropland |
135,974 |
97,260 |
52,341 |
|
Natural pastures |
1,046,620 |
861,895 |
184,725 |
|
Improved pastures |
96,259 |
0 |
98,259 |
|
Commercial forest |
100,916 |
0 |
100,916 |
|
Other |
341,846 |
5,925 |
320,294 |
|
Total |
1,721,615 |
965,080 |
756,535 |
Source: CSO 1982.
Several features of Swaziland's grazing resources may be discerned from Table 2. Firstly, improved or cultivated pastures contribute less than 10% of the total grazing resource. They are established exclusively on ITF. Secondly, native pastures or veld occupy some 90% of SNL while they form only a small proportion of title-deed land.
Under Swaziland's system of conversion, the total livestock population presented in Table 1 is equivalent to 617,000 livestock units which gives a crude stocking rate of 1.7 hectares per livestock unit on native veld, the major grazing resource. This value is undoubtedly well above the estimated carrying capacity of much of the veld and is reflected in the observed low animal productivity and degraded range condition, especially on SNL (Ions and Kidner 1967).
Another important feature of Swaziland's pastures, whether natural or planted, is their relatively low nutritive value for most of the year. Many forage species grow very rapidly as soon as the rains commence in early summer (October). At this time leaf production is high and crude protein content and digestibility are satisfactory (Ogwang 1985b). By the end of the wet season (March), the plants develop tall flowering stems which are low in protein and high in fibre. These conditions place severe restrictions on livestock production, particularly during the dry season which can be as long as seven months. The present paper discusses some of the strategies that could be used to minimize the winter-feed problem thereby improving overall livestock production throughout the year.
Pasture production is usually related to seasonal rainfall distribution which in Swaziland is restricted to only a few months of the year. Consequently stock owners who rely exclusively on pastures experience periods of excess forage in the wet months alternating with periods of scarcity in winter. In order to sustain uninterrupted livestock production, the stockowner should be able to adjust to this fluctuating feed supply. To some extent this could be achieved through seasonal disposal and purchase of livestock while the winter feed deficit could be improved by a number of measures, as described below.
Irrigation
Pasture production can be extended into the dry winter months through irrigation, subject to limitations of light and temperature. Cool-season grasses such as oats, rye grass and triticale have been grown successfully for dairy production in some parts of the country. It has also been shown that the yield and the feed value of the grasses can be considerably enhanced by the inclusion of temperate legumes such as vetch or red clover (Whitmarsh 1977). Approximately 37,000 hectares of land are currently irrigated in Swaziland of which 1,200 hectares are on SNL and the rest on individual farms and company estates. While the cotton, rice and sugarcane, opportunities for pasture establishment could be investigated.
Use of Fertilizers
In terms of quantity, by far the most important farm input used, particularly on SN, is fertilizer. An estimated 46,500 tonnes of fertilizer were used in Swaziland during the 1980/81 season (Anonymous 1983a). This represented an average application rate of 320 kg per cropped hectare. At present the bulk of the fertilizer used on SNL is reserved for maize and cotton and very little appears to be used for pasture establishment. While the cost of pasture fertilization may appear unattractive, possibilities for strategic application of small quantities just before the end of the growing season need to be investigated. Fertilizers could extend the period of pasture production into the dry season and any surplus will remain in the soil during the winter months to stimulate active growth with the new rains in spring.
Use of Drought-Tolerant Species
Pasture species capable of growing out of season can be planted to prolong the period of good-quality forage. Drought-tolerant legumes can be particularly useful in this regard. They can benefit ruminants through their high productivity, high protein content and high mineral status. That the use of legumes is not widespread in Swaziland probably reflects the limited knowledge of their agronomic characteristics and adaptability to the local environment. Some success has been recorded with a few legumes such as Desmodium and stylo (Whitmarsh 1975) and the need to explore more of them was recently emphasized by Ogwang (1985a).
Shrub legumes such as pigeon peas and Leucaena have been successfully established around homesteads and grass strips in other sub-tropical countries. They are not only drought resistant but also offer a variety of domestic uses besides being important dry-season feeds. Their potential for Swaziland needs to be investigated.
Conservation of Excess Forage as Silage
The production of silage is currently practiced on a limited scale in Swaziland. Small quantities of maize silage are produced on a number of dairy farms around the country. Both bane grass and Napier grass have been shown locally to have higher yields than maize (Whitmarsh 1977). If cut with a forage harvester before they become too mature these giant grasses are no more difficult to ensile than maize, although they do have a higher protein content necessitating the addition of a carbohydrate supplement such as molasses. There is a need to re-examine the potential limitations of silage making under Swaziland conditions.
Conservation of Excess Forage as Hay
In Swaziland, hay making is practiced on livestock breeding stations and in a number of ranches. The production of hay from natural as well as improved pastures can be an easy and cheap method of conserving forage. Its present lack of popularity emphasizes the need for more research on the quality of the various forage species available, appropriate techniques for cutting, drying and storing the hay, and the socio-economic viability of such technologies.
Conservation of Forage as Standing Hay
Where a decline in quality can be tolerated, forage can also be stored as standing hay. This is generally the cheapest way of conserving forage. On fenced grazing land, standing hay may be conserved by leaving one or two areas/paddocks ungrazed during the last part of the growing season. It can then be utilized during the dry season when forage from other areas is no longer available in adequate quantities. Even on communal grazing land, certain areas could be reserved during the growing season and grazed later.
Crop Residues
A wide variety of arable crops is grown both on SNL and ITF for subsistence. Many of these crops have residues which can form an important source of livestock feed. Yields of some of the common crops grown are presented in Tables 3 and 4 respectively.
Table 3. Area and production of major crops grown on SNL, 1981/82
|
Crop (tonnes) |
Area |
Production |
|
Maize |
58,936 |
52,267 |
|
Sorghum |
2,168 |
720 |
|
Cotton |
11,575 |
8,445 |
|
Beans |
2,071 |
404 |
|
Groundnuts |
1,665 |
481 |
|
Sweet potatoes |
910 |
1,192 |
Source: CSO 1982.
Tables 3 and 4 indicate the potential variety and abundance of crop residues that could be used for livestock feeding in Swaziland. The contribution of such residues to total available feed resources has been reported to vary from 6% in some regions to 2% in the Rural Development Areas (Anonymous 1983b).
Table 4. Area and production of major crops grown on ITF, 1981/82
|
Crop |
Area (ha) |
Production (tonnes) |
|
Sugarcane |
30,819 |
3,249,659 |
|
Cotton |
not available |
5,810 |
|
Pineapples |
1,552 |
33,150 |
|
Citrus |
not available |
58,492 |
|
Oranges |
not available |
33,249 |
Sources: Central Statistics Office; Sugar Association; Swaziland Citrus Board
Yields of cereal stover may be expected to vary depending on season, inputs and skill of the farmer. Maize stover, for example, has a digestible CP content of 2.3% on a dry-matter basis and a TDN of 57%. This compares with 2.5% pop and 52% TDN for very good quality veld or poor quality Eragrostis curvula hay. Opportunities for improving the quality of dry cereal crop residues through treatment with chemicals such as urea, NaOH nd NH3 could be investigated.
Whenever available, grain legumes such as groundnuts and beans should provide good-quality roughage after the crops have been harvested.
The most important vegetables grown in Swaziland include sweet potatoes, pumpkins, cabbages, tomatoes and onions. The non-marketable parts of sweet potatoes and cabbages can provide feed of high value compared to dry-crop residues. They are difficult to store and would therefore be more suitable for daily feedings.
It has been shown in other countries that sugarcane can be used as the basis of intensive animal production systems. In the Philippines, for example, a number of sugarcane producers experimented with fattening cattle using sugarcane tops as basal diets. Their results showed average daily weight gains per cow of 0.5-0.7 kg (Guzman and Lee 1978). Sugarcane is the most important export crop in Swaziland and the tops could form an important feed source for animals raised around sugarcane growing areas. Molasses is another feed which is being used very extensively in other countries.
Pineapple and citrus wastes may be regarded as high-energy feed for livestock. They are high in sugar, low in protein and fairly high in fibre. Swazican produces a large quantity of these wastes at Malkerns but they are largely thrown away due to the lack of appropriate technology and economic methods of utilization. Suitable methods of conservation could be devised. The addition of formic acid and urea to ensiled pineapple waste has been shown to significantly improve the digestibility of the nutrients (Lebbie, personal communication).
Agro-industrial By-Products
Potential agro-industrial by products for livestock feeding include molasses, bagasse and cotton-seed cake. About 138,000 tonnes of molasses were produced in 1982 in Swaziland (CSO 1982). This could be used to supply energy in conjunction with poor-quality forage in the dry season. Bagasse, another sugar-processing by-product, is generally of low quality due to high content of fibre and Lignin. However, the quality can be significantly improved through heat or alkali treatment.
At present no oilseeds are produced as a primary commodity in Swaziland. Cotton seed is exported mainly to South Africa where oil is expressed from it for domestic use. There is some potential for making good-quality animal feed if the seeds could be processed locally.
Concentrate Supplementation
Cereal grains such as maize and sorghum hay-e a high feed value. They can contribute significantly to animal output. However, most of the grains grown in Swaziland are primarily for human consumption. This, together with the high cost of concentrates, renders them inappropriate as livestock feed unless very high yielding animals are used.
In conclusion, it should be pointed out that there is considerable opportunity for increasing pasture production and the availability of non-conventional feedstuffs in Swaziland. Veld improvement can be effected through bold policies such as destocking, fencing and bush clearing. Planted pastures need considerable inputs such as fertilizers and, although the economics of such undertakings have often been questioned, the possibility of strategic application of small quantities could be explored. The inclusion of both herbaceous and shrub legumes in the cropping systems can significantly cut such production costs. Considerable opportunities also exist for the use of crop residues and agro-industrial by-products. What is needed is a comprehensive inventory of the feed sources coupled with appropriate technologies for improving their nutritional values.
Anonymous. (1983a). Livestock industry development study. Report by Hunting Technical-Services to the Swaziland Government. Department of Economic Planning and Statistics, Mbabane.
Anonymous. (1983b). Review of the Rural Development Areas Programme. Final Report (Annexes). Report by Hunting Technical Services to the Swaziland Government. Ministry of Agriculture and Cooperatives, Mbabane.
CSO (Central Statistical Office). (1982). Annual Statistical Bulletin, Central Statistics Office, Mbabane.
Guzman, M.R. and Lee, N.S. (1978). Integration of backyard dairy-beef farming with cropping systems and feed grain substitutes for cattle. Food and Fertilizer Technology Bulletin No. 110. Taiwan, Republic of China.
Ions, J.H. and Kidner, E.M. (1967). Veld and pasture management in Swaziland. Bulletin No. 17, Ministry of Agriculture and Cooperatives, Mbabane.
Ogwang, B.H. (1985a). Research on forage legumes in Swaziland. Paper presented at a workshop on potentials of forage legumes in farming systems in Sub-Saharan Africa. Addis Ababa, Ethiopia, 16-19 September 1985.
Ogwang, B.H. (1985b). Chemical composition of native pastures in the middleveld of Swaziland. Unpublished report, University of Swaziland.
Whitmarsh, A.R.T. (1975). Guide to pasture field trials 1975/76. University of Botswana, Lesotho and Swaziland. Faculty of Agriculture, Research Division, Miscellaneous Report No. 111.
Whitmarsh, A.R.T. (1977). Improved pasture production in the middleveld of Swaziland: Some tentative recommendations based on results of recent trials at Malkerns, 1974-1977. Advisory Bulletin No. 12, Malkerns Research Station.
