1 Background

Introduction

The International Livestock Research Institute (ILRI) and the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) are undertaking a joint research project to identify ruminant quality traits of sorghum and millet crop residues to be included in crop improvement programmes. The final objective of this research is to be able, in collaboration with the national programmes, to offer farmers improved sorghum and millet varieties that have better quality and more digestible crop residues to feed to their livestock.

Sorghum and millet crop residues play a major role in meeting the feed requirements of cattle and buffalo in most of the smallholder mixed crop–livestock farming systems in India’s semi-arid tropics (SAT). Quantity and quality of feed heavily influence livestock productivity. This genetic research should result in greater quantities of and more digestible feed available to livestock, that will in turn convert the improved diet into more milk, meat, manure and draft power. While this investigation focuses on opportunities for improving livestock productivity through better quality feed, there are other constraints limiting productivity increases that are beyond the scope of this study, but will influence ultimate adoption rates of the new varieties developed as a result of this research.

This ex ante impact assessment measures the potential economic impact of and returns to investment in this area of research. The analysis does not capture all the potential benefits to the research, but focuses on those livestock products that are the easiest to value, namely milk and meat. This does not imply that other livestock products such as manure and traction are not as or more important to the smallholder farming families potentially interested in the new crop varieties. Similarly, while the primary focus is impact in India, potential impacts in other regions of the world may also be substantial, but are not quantified in this analysis.

Sorghum and millet crop residues research

Cereal crop residues, also called stover or straw, are the parts of the plant remaining after the grain crop has been harvested. They include the leaves and stems. Residues can be collected and removed from the field, then chopped and stored for feeding animals during periods when range grazing is unavailable (the most common practice followed in India).  Alternatively, the straw can be left standing and the livestock allowed to graze (a common practice in the SAT of Africa). Apart from being a source of animal feed, residues are used as building, roofing and fencing materials, as fuel and as fertiliser or surface mulch on crops.  The proportion of total crop residues allocated to feed depends on such factors as livestock density and rules of access, that are in turn influenced by land tenure, the relative importance of livestock in the farming system and access to markets for livestock products (de Leeuw 1997). The main agricultural systems where crop residues are produced and used in India are presented in Table 1.1.

The breeding programmes of ICRISAT and the Indian national agricultural research system (NARS) have traditionally focused on increasing grain yield potential through incorporation of resistance to major biotic and abiotic yield reducers and selection of genotypes responsive to good management (Kelley et al 1993). Straw quality and straw yields are beginning to receive attention since there is now evidence that in more marginal environments, there is low adoption of modern cultivars due to perceptions by farmers that, despite lower grain yields, their traditional varieties provide more, higher-quality straw (Kelley and Rao 1994). Traxler and Byerlee (1993) discussed the slow adoption of modern cereal varieties with high grain yields but lower straw yields in some developing countries where straw is an important source of animal fodder for smallholders. A farmer participatory approach to selection of improved sorghum varieties was taken by ICRISAT in the Indian State of Andhra Pradesh in an area where farmers were rejecting higher-yielding grain-type sorghums (Anders and Satyanarayana 1994). The researchers found that due to the farmers’ reliance on livestock for draft power, milk and income generation, they consistently selected a sorghum type that would not compromise fodder weight or quality but would produce more grain.  

Dual-purpose varieties of millet and sorghum that provide both grains for food and straw for animal fodder are very important to farmers who care as much about fodder yields as they do about grain yields. The importance of sorghum and millet residues varies by production system and by season across South Asia. Sorghum straw was found to contribute between 20% and 45% of the total dry weight fed to dairy animals by smallholders in western Maharashtra (Thole et al 1988). In south India, dry fodder was found to provide 13% of the dry matter fed by smallholder dairy owners from August to October (wet season), but more than 50% from January to April (dry season) (McDowell 1988). The increasing importance of sorghum straw is reflected in its market price, which in parts of India has been increasing relative to the price of the grain. In Solapur, Maharashtra, the grain/straw price ratio fell from around 6.0 in the early 1970s to 2.5 in the early 1990s (Kelley et al 1993).

There is an increasing demand for all types of livestock feed in India because there are:  1) significant increases in the number of indigenous and improved cattle and buffalo (from 246 million head in 1984 to 271 million head in 1993—a 10.2% increase); 2) an increase in the amount of milk produced (from 38.7 million tonnes in 1984 to 61 million tonnes in 1993—a 58% increase) (FAO 1987; FAO 1996);  3) the area and quality of grazing lands have been, and are expected to, continue to decline (Bhaskara Rao 1994); and 4) fallow phases in crop rotations are becoming less frequent (Anders and Satyanarayana 1994).

Approach

This ex ante assessment of the returns to research links three methodologies to measure how much impact, where and how to value it. A feed simulation model is used to measure the potential productivity gains from more, higher-quality crop residqes in terms of meat and milk output. Primary survey data and geographic information systems (GIS) analyses of secondary data are used to assess where these gains are likely to be made. An economic surplus model that links the results of the GIS analysis with the output from the feed model is used to value the potential benefits versus the costs of the research.

The results of this analysis are useful for several purposes. As resources for agricultural research and development become increasingly scarce world-wide (Anderson et al 1994), ex ante impact assessments of the potential benefits and costs of research investments are now being used by national and international research centres to aid in priority setting and resource allocation (see Kristjanson (1997), for a description of ILRI’s research priority-setting approach, and Kelley et al (1995) for ICRISAT’s). With a wide range of research and development approaches to choose from, donors are interested in seeing analyses of the potential impact of various types of investment. An ex ante analysis addresses issues that ensure the research is well targeted and the path from research station to the farmer is clear.