There are many ways in which the farmers may improve the value of their low quality forages and crop residues. These range from a minimum supplement (multinutrient blocks), to relatively delicate treatment methods using anhydrous ammonia or to urea treatment, a method which is easy to propose to the small farmer.
The objective of this Chapter is to make a rapid appraisal of the socio-economic factors which should be taken into account during any extension programme concerning these techniques so as to highlight the constraints to overcome and the advantages to take so as to ensure their development with particular emphasis on treatment.
The justification for using treatment techniques and/or feed supplements consists in linking, on the one hand, the nutritional requirements which depend on the nature and the functional production system of the animal and, on the other hand, with the geographic and seasonal availability of forage resources and of their quality. It is therefore important to distinguish between production systems according to the availability and the importance which forages and crop residues represent as forage resources (BOUTONNET, 1994).
The other question which often presents itself is whether it is more advantageous to treat the low quality forages or to add supplements. From a strictly technical point of view there is no doubt about the answer: one may make the animal produce just as much with treated straw as with supplemented natural forage, provided the nutritional restrictions described in Chapter 6 are observed so as to optimize the fibre fraction of the ration. From a socio-economic standpoint, the answer is much less clear and an in depth analysis of the local context must be taken into account concerning on the one hand, the market of inputs and products and, on the other, the nature and function of the production systems.
If one first rules out consideration of extensive systems consisting of large herds feeding off open pasture land (rangelands), either on the move (nomads or transhumants) or fixed (ranching) which do not use crop residues (BOUTONNET, 1994), we may bring together schematically the various combinations of forage resources/animal production systems which are very diverse, into four general situations for which the approach and considerations will be totally different. These are outlined in the following table:
|Coarse forage resources (the offer)||Animals (the demand)|
|Low production||High production|
|Abundant||Case 1||Case 3|
This is the situation in many developing countries with abundant but seasonally available forage where one finds more or less juxtaposed:
intensive cropping systems producing large amounts of vegetal biomass of which the crop residues of “poor” quality are not subjected to optimum usage,
livestock systems of low productivity. The animals in this case are potential users of the byproducts. Integrating the livestock production with agriculture constitutes a means to intensify the system.
Examples of such systems are to be found in the irrigated perimeters along the Niger and Senegal rivers, the Nile delta and valley in Egypt, South East Asia and Central China.
Straw might only be available in limited quantities and seasonally but it might constitute the only resource additional to the classic forages, either pastured or cut and harvested. As such, it constitutes an asset for which, in principal, any technique which can improve its nutritional value is beneficial.
The strictly economic aspects weigh less heavily on the decision making process of the farmer than firstly, availability of funds and forage resources and secondly, the urgent need to improve production (milk, meat, work efficiency). The decision will depend upon the results of balancing the inputs/outputs (the “forecast budget”) for each of the two hypotheses, supplementation or treatment.
Simplified cost/benefit calculation of the economics of treatment. Example taken from the High Plateau Region, Madagascar (Chenost, 1993)
|For a pit measuring 2 m × 1 m × 1 m = 2 m3||which will allow treating 200 kg of dry straw|
|- plastic (a strip 1.5 m wide @ 650 FMG(2)/ m2)|
|12 m(1) × 1.5 m = 18 m2|
|ie. 18 m2 × 650 FMG = 11,700 FMG|
|Cost||per treatment||per kg of treated straw|
|-(1) two treatments per year over 1 year: 11,700 / 2||=5,850 FMG||5,850/200 = 29 FMG|
|-(2) two treatments per year over 4 years: 11,700 / (2 × 4)||=1,460 FMG||1,460/200 =7 FMG|
|- urea (700 FMG / kg)|
|dosage of 6 kg per 100 kg of dry straw|
|i.e. 12 kg for 200 kg of dry straw to be treated|
|12 kg × 700 FMG = 8,400 FMG|
|Cost||per kg of treated straw|
|8,400 / 200 =||42 FMG|
|- cost of plastic + urea|
|-hypothesis (1), reused twice||42 + 29 = 71 FMG|
|-hypothesis (2), reused 8 times||42 + 7 = 49 FMG|
A realistic hypothesis will be made(3) by which 5 kg/day of treated straw can provoke an increased milk production by the cow of 1.5 kg/day, compared to feeding non-treated straw.
|Cash receipts will increase as follows:|
|1.5 kg @ 500 FMG/kg = 750 FMG, for 5 kg of treated straw, which is: per kg of treated straw||per kg of treated straw|
|750 / 15 = 150 FMG|
|Hence the benefit per kg of treated straw is:|
|hypothesis (1)||150 - 71 FMG, rounded to:||80 FMG|
|hypothesis (2)||150 - 49 FMG, rounded to:||100 FMG|
(1) - une bande de 0,5 + 1,0 + 2,0 + 1,0 + 0,5 m pour tapisser la fosse dans le sens de la of 0.5 m for sealing …………………………………………………………………………………5.0 m
- two double strips of 0.5 + 1.0 + 0.25 m to cover the pit across its width, leaving alength of 0.5 m for sealing and a length of 0.25 m for the footing on each strip ………………………………7.0 m
(2) - FMG = Malgache Francs (1 French Franc = 317 FMG) on 1/1/93
(3) - Observed during a survey of livestock farmers (see Table 27).
The example from Madagascar well illustrates these situations and shows that the simple calculation of cost/benefit is an important element for decision making and sufficient in itself.
The decision between treating and supplementing is closely related to the availability of inputs and to their cost (urea, cereal byproducts). Table 30 illustrates an example of a ration for draft animals in moderate condition for work which shows that the decision depends upon a comparison of the following costs, sufficient to cover the same requirements of the animal over a 4 month period:
the cost of 360 kg of bran which is needed to supplement 600 kg of non-treated straw
the cost of 42 kg of urea, needed to treat 840 kg of straw, plus 60 kg of bran supplement.
And finally the decision will be made easier by the fact that in these countries, the supplements must never enter into competition with domestic food or, in some cases, with exports (a source of foreign exchange at national level).
This represents the systems practised in the arid steppe zones with basins of dryland or irrigated cereal production such as in North Africa and the Near east. The range of different systems can be quite large passing from an extensive grazing system to intensive landless systems, with all the intermediate possibilities according to the importance of the forages and byproducts (grown or purchased) in the ration.
Vegetal matter is scarce in comparison with the needs of the animals. Straw, although used by tradition, might not only be scarce but be found in competition with other cheaper feed resources such as barley, either locally grown or imported. It is important in these situations to reflect upon the economic opportunity afforded by improved methods before diffusing them unconditionally. Arguments other than those which are purely economic (eg. animal production and health) can hold the interest of the livestock farmers in these techniques. In effect, the coarse forages are considered as the essential fibrous element in the ruminant's diet.
Nutritional and production aspects:
It should be recalled (see Chapters 6 and 7) that treated forages are only nutritionally beneficial when they make up the major proportion of the ration (roughly, at least half). Lower proportions involve symptoms of negative associative digestibility which effectively “erase” the effects due to treatment.
Furthermore, even if treated, low quality forages will still have insufficient nutritional value for making up the major portion of a ration designed for highly productive and exigent animals.
It is convenient to give this type of ration to animals from the herd which have only moderate requirements due to their physiological condition (heifers at the end of their growth, cows or ewes at the end of lactation) which will become the “target animals”, the more productive animals receiving, where possible, the best quality forages.
It is essential to use survey methods to allow identification of operational aspects of the system and in order to gauge the chances of success for the proposed techniques. This is particularly important in these regions as concentrates are often imported or their price subsidized and can become cheaper than straw which can attain a high price when forage is out of season.
For these reasons, a “Guide” has recently been published by Boutonnet and Mercier (1994). This proposes a methodology for decision makers in the form of a list of questions which should be made before extension of treatment techniques.
The objective is to arrive at a rapid appraisal of the interests for a livestock farmer to treat. The guide places the reader as the farmer, in other words, the forage producer who is enquiring as to the best economic use for his resources.
The proposed study consists of two stages:
1/ Market study: surveying and understanding the forage market; characteristics of the product under study (treated straw) and products which can be substituted, study of the product market (trading conditions for these products), comparison of nutritional values.
2/ Study of the role of the product (straw) in the livestock production systems: knowledge of the animal species concerned, animal production levels reached (in meat, milk, animal fibre, …), importance of non-treated straw in the ration so as to appreciate conditions for its use and specially, the nature and amount of supplement given, survey of the livestock production systems and their production levels.
The study follows the following sequence of events:
description of the product under study,
description of products which might be substituted,
market study for these products,
conclusion as to the competitive level of the product,
description of the livestock farming systems in the region under study,
choice of the livestock categories to be surveyed, selected from amongst the different livestock production systems,
survey interviews with 2 or 3 farmers from each category,
calculation of characteristic proportions making up each livestock production system (the importance of each type of forage in the ration),
conclusion concerning the livestock farming systems,
conclusion concerning the market and the livestock production systems.
Both of the following nutritional and economic aspects should be incorporated into the conclusions, at least in spirit (for a positive report):
there is nutritional interest when the proportion of straw in the ration is over 50 % DM.
there is economic interest when (I) the cost of energy purchased in the form of concentrates is more than the supplementary energy procured by treating the straw; and/or (ii) when the value (at market prices) of straw or of the hay which has been saved (because of reduction of left-overs due to treatment) is higher than the treatment cost (in this case, the farmer can sell any which is surplus to his requirements on the market).
This method of analysis has recently been successfully tested in Morocco, Jordan and Syria, countries practising both livestock and cereal production but with differing constraints concerning straw availability: Morocco and Jordan have only limited supplies, Syria has straw in abundance.
This represents the typical mixed farming system. The animals mainly consume agricultural or domestic byproducts, topped up by pasturing and/or forage crops either grown on the farm or purchased (BOUTONNET, 1994). Also to be included in this group is the specialised stable for intensive animal production (milk, for example) which, in the limit, becomes landless when all feed is purchased (Case 4).
The animals which are intensively managed, often have high performance rates (being prolific, producing milk and meat) and the economic approach preceding any decision to treat forage must be more precise.
This requires a fuller calculation allowing determination of the limiting treatment cost above which treatment will no longer be profitable (the maximum allowable cost). This cost may be calculated on the basis of the following relational equality:
cost of a treated straw ration = cost of a non-treated straw ration with supplements
whereby the two rations ensure the same production levels.
This equality may be expressed in the form of an equation (LIENARD and DULPHY, 1987):
T(Pnt + Tr) + Ct × ct = NT × Pnt + Cnt × cnt
T = intake of treated straw (kg)
NT = intake of non-treated straw (kg)
Pnt = cost / kg of non-treated straw
Tr = cost / kg of treated straw
Ct = quantity of concentrate ingested with the treated straw (kg)
ct = cost / kg of the concentrate for the treated straw
Cnt = quantity of concentrate ingested with the non-treated straw (kg)
cnt = cost / kg of the concentrate for the non-treated straw
The maximum cost of treatment which should not be exceeded may be calculated from this formula:
Tr = [(Cnt × cnt) - (Ct × ct) - (T - NT) × Pnt] / T
= (reduction in concentrate - increase in straw) / intake treated straw consumed consumed
This simple formula shows, amongst other things, that the maximum allowable cost and hence potential interest in treating, are higher when:
a greatly reduced need for concentrates can be achieved
the cost of the concentrates is high
and interest in treating is low and hence difficult to justify economically when:
the cost of straw is high
the cost of concentrates is low
The formula also allows the calculation of a whole family of curves showing the limiting costs for treating according to the straw and supplement costs, the respective amounts of straw and supplements, hence, according to the initial straw quality and the treatment efficiency and also, for different types of animal receiving the ration (intake amounts and thus, production levels).
Nutritional aspects (target animals):
Apart from the economic considerations, it is important, particularly for this category of production systems and for the reasons already given above, to reserve here also the treated roughage for those animals of the herd with only moderate requirements.
Whichever is the type of agro-economic situation, the treatment to be undertaken implies a certain cost made up of the following components:
the cost and quantity of the treatment agent (ammonia, urea),
the cost incurred to ensure an airtight seal of the treatment environment: the fixed enclosure (depreciation cost as this can be used again) or temporary enclosure (with walls made from local materials, canvas covers or plastic sheeting, …), the cover for the forage.
the labour costs involved with undertaking the treatment.
The objective here is not to undertake detailed calculations of all these items, rather it is to emphasise, in the author's experience, where savings may be made. Reference will be made to the practical aspects of treatment already described above in Chapter 3.
Treating with anhydrous ammonia
Many economic studies have been made concerning the treatment costs per kg of straw. Amongst these, it has been shown that the unit treatment costs depends on the technique used and the amount of forage treated (ZWAENEPOEL and LIENARD, 1987). Treating a stack proves always to be the most economic method to adopt. However under European conditions, treating by injecting round bales becomes similar in cost to batch treatment when annual tonnages exceed 300 tons. The main saving which can be made by treating a stack is that the lower layer of plastic is not required, an airtight seal being achieved by carefully burying the sides of the plastic cover into the soil all around the stack.
It is also well understood that the heavy investments (tanks, …) are very high and can only be envisaged on a scale for farmer groups or cooperatives. This technique can rarely be justified in developing countries.
Only few savings may be made in urea treatment regarding the amount of urea used. However this aspect might be reviewed in the future if the efficiency in treating with a urea/lime mix is confirmed. It has been shown above (§ 422) that the amount of urea should not fall below 5 kg per 100 kg of straw if good treatment is to be guaranteed.
In contrast, it is mainly concerning the type of enclosure and of the covering material where one may consider alternatives, as mentioned above in § 431. The study mentioned above concerning Morocco shows that the cost of the plastic represents 70 % of the total treatment cost.
The use of locally available raw materials for small volumes to be treated and forming the airtight seal with mud (Morocco, Tunisia, …) or a mixture of mud and manure, or even self coverage by a layer of straw “sacrificed” for the purpose of treating large volumes, represent the main means for saving on the unit treatment costs.
Urea treatment is particularly adapted to the needs of small farms and producers. Its simplicity allows it to be undertaken without calling in help from external paid labour teams. It is usually undertaken by the family members, assisted by the neighbours (reciprocal exchange of services).
The example from China is interesting from two main points of view (FINLAYSON, 1993; DOLBERG and FINLAYSON, 1995):
This shows that with regard to supplements, those such as cotton cake prove to be perfectly appropriate from a nutritional aspect for obtaining maximum benefits from the treated straw. It shows that it is certainly not necessary to insist on the use of commercial concentrates which are often poorly balanced and costly.
Concerning quantities, the response curves of growth rate, considered together with the economic analysis, show that the optimum animal production achieved with 2 to 3 kg/day/animal of cake, does not necessarily coincide with the optimum quantity calculated by the economic analysis. This optimum quantity changes again (FINLAYSON, 1993) if one considers profit per head of cattle fattened (the figure in this case is 1 kg) or alternatively, profit per day of fattening (this comes to 2 kg). The optimum profit per head applies to a farmer who only fattens one group of animals during the year whereas the optimum profit per day is of interest to the farmer fattening several groups of animals throughout the year.
The importance of practical trials and the selection of target farmers
Apart from being a valuable source of technical and economic references, demonstration trials and, even more so, controlled trials conducted alongside the farmers have enormous value for the extension services as they bear witness to the farmer's experiences. Above all they are interesting for verification of whether the technique proposed is well adapted to the farming system for which it will be diffused. It is most important to plan these types of trials in development programmes.
Another aspect of equal importance consists in the selection of the farmers where the trials and demonstrations will be undertaken. In order that the message will not be forgotten after departure of the extension agent, one must select “target” farmers who are sufficiently motivated and persuasive before their neighbours. They will then form the veritable “chain of transmission” (training in cascade) for wider diffusion of the technique.
The target regions might be isolated and far from agricultural zones and so not benefit from a urea distribution network. This is the case of some pastoral villages in the Sahel region or the mountainous areas of Africa and Madagascar. They might however be interested in urea treatment or in making the multinutrient blocks. It is most important that the public authorities, both national and regional, take appropriate measures to allow livestock production groups or local cooperatives to benefit from the necessary supply of urea and other inputs so that they may become self-sufficient.
Short term credit for purchase of the inputs
Due to lack of ready cash, farmers are often unable to purchase even the minimum amount of urea needed to start and follow through the treatment operations. However, they realise that their profits will eventually be greater than before. Simple measures consisting of short term credit schemes will be essential to start up and carry on the pilot activities.
Speed and perception of the animal production response to treatment and supplements: the chances for adoption of the technique by the farmers
It is generally the effect on milk production which constitutes the greatest advantage and that which will govern the speed and perception of the new feeding technique by the farmers. The farmer experiences in Cambodia and Niger (see Chapter 7) who noticed the much better working efficiency of their draft animals after having been fed treated straw, also serves as confirmation of the efficiency of the technique for these animals.
In contrast, whilst growing animals also respond to these techniques, they do so more slowly. It is therefore important in this case, that in addition to offering credit facilities (see above) that the extension agents are themselves sufficiently convinced as to be sufficiently persuasive in front of the farmer, encouraging him to persevere with the technique even though he might not notice immediate results.
Variability in the nutritional value of the straw types
Straw is often considered as a crop residue whereas in most production systems, the Mediterranean, the Sahel, Madagascar, Asia, … it is truly a forage resource. Western systems have “biased” too much the thinking in terms of grain production and it is urgent to take greater interest than before in the differences in quality of the stalks and straw in terms of their nutritional value for animals.
It has already been shown that the nutritional value of different straw types varies considerably. But there is still a lack of the necessary instruments (estimators) to quickly evaluate (in the field) or precisely (in the laboratory) the nutritional value of the straw. This point has already been highlighted for follow-up by research workers and development agents. As it is already known that straw responds less well to treatment when its nutritional value is high, it is most important to be able rapidly to perfect these evaluation techniques.
One of the authors' hopes is that this present document, in its own way, will encourage those readers having any power of decision to assist as follows:
on the one hand, to encourage the nutritionists to undertake further research concerning these “estimators”
and on the other, to encourage the crop genetists to use these instruments more than previously in programmes designed to improve straw quality of cereals, an aspect which for too long has been relegated to only secondary consideration after concentrating the main efforts on grain productivity.
Programmes for improvement of species and forage production are long term operations which can be rather dissuasive. However they should not be underestimated. Their final objective is not only to improve the feed for the ruminants but also to improve the overall agricultural system.
Establishing simple techniques which allow improving the value of crop residues is attractive as it is quick. However, it only represents improvement to one aspect of the existing system.
It is important that those decision makers responsible for agricultural development respect the precise roles of these two groups of techniques and that one is not privileged at the expense of the other.
The example from North Africa demonstrates very well how easy it is in the cereal/livestock systems of this region, to adopt unconditionally straw treatment with either urea or anhydrous ammonia, substituting the classic forages such as vetch/oats which are more exigent and for which it is more difficult to achieve sucess and for which areas under cultivation are in regression, in contrast to those under cereals.
The example of Madagascar is different and the utilisation of treated rice straw in the cattle feed on the high plateaux represents a supplementary solution to the more long term and important programme for introducing forage to these regions.
The extension of a technical theme such as improving the value of crop residues for animal feed, particularly through urea treatment, is accompanied by both positive and negative effects, some of which might not have been foreseen and all of which should be duly considered.
Straw treatment with urea encourages the farmers to burn it less than before. Management of the forage resources is thus improved. The livestock farmers can better commercialise the straw, but at prices which are relatively high for those who do not have their own supplies and who must generally buy in feed for their animals. Moreover, the positive effect of treatment consists in improving management of the forage resources.
Treatment develops a spirit of solidarity amongst the villagers or the community through the organisation of work groups for the operation and through the mutual interchange of services.
It also contributes towards better integration of livestock production within the agricultural system: improvement of soil fertility (by supplying manure of better quality) but above all improving the efficiency of animal traction which is added to the possibilities of fattening.
This technique has become a type of focal point around which many other actions for improving animal production techniques may be attached: construction of feeding troughs and stalls, the more rational use of forage and feed supplements, the collection and distribution of manure, health care (essentially treatment of parasites), etc…
It also constitutes for the extension agent, an occasion to become much more interested in the true problems at field level than through routine campaigns for vaccination.
Urea treatment of crop residues implies that they must be harvested and stored. Before introducing this innovation, it is convenient to know how these residues are used and managed both within the farm and through exchange systems with other farmers. It is essential to learn the consequences which could result from diffusing the technique. The following points illustrate a few of these worries:
maintenance of soil fertility: it is not unusual to find cases where farmers who harvest the stalks from their millet, sorghum and maize by pulling up the roots, rendering the soil more fragile;
the agricultural and livestock activities, will they become integrated or sources of conflict? It is necessary to take into account the agreements amongst farmers and shepherds in the agro-pastoral systems of the Sahel (a contract for manure against one for staying on the land) by which the farmers leave the shepherds their crop residues for grazing. The farmer benefits in return from the organic manure left by the animals. In these traditional systems, the shepherds and agro-shepherds have become much more sedentary and their flocks can cause conflicts concerning the crop residues which constitute the main feed source for the flock and even, a source of domestic fuel and a raw material for construction (banco).
Improving the nutritional value of low quality forages through urea treatment is becoming more and more popular in developing countries. Furthermore, most of the farmers who have practised the technique are unanimous in their comments:
the simplicity and low cost of the method (often only the urea has to be purchased) and the fact that it may be undertaken by the farmers themselves with locally available materials,
the efficiency of the method which improves the quality of their straw, the basic ingredient of the feed ration for their animals.
In addition, for many of these countries the technique of urea treatment now forms part of the development strategy for their animal production system. The technique is also now widely used by development and training projects for livestock production, both bilateral (Sri Lanka, …) and multilateral (see Appendix 7). In this respect, the World Bank has now inscribed it in its arsenal of interventions at field level. Its diffusion has mainly been initiated by the Animal Production and Health Division of FAO with support from the Technical Cooperation Programme (TCP) or in collaboration with other donors (the case, for example, of the development project in Tanzania for small scale milk production). The list of countries having already started up urea treatment has already been given. China represents the choice example as regards the impact of the technique on development.
From the economic point of view, any technique for improving the value of low quality forages (multinutrient blocks, treatment) is better justified when these are readily available (geographically and seasonally) and as the importance of their role as feed within the agricultural production system increases.
In addition, from a nutritional and animal production point of view, the use of feed supplements and treated low quality forages give better performance improvement to those animals which are the weakest from the start.
In the case of most developing countries where supplies of low quality forages are not limited and where animal production levels are only modest (Case 1), the prime objective of the farmer is to improve the productivity of his animals in terms of milk production, meat production and work efficiency of the draft animals. Thus the decision as to whether the technique should be adopted depends essentially upon the cost/benefit relationship which will result.
Where forage supplies are limited and the level of animal production is modest (Case 2), a more in-depth analysis concerning the local context should be made (the market values of inputs and animal products, the nature and operation of the production systems). A methodology has recently been proposed in North Africa for analyzing such situations which are typical in this region.
And finally, in countries with a developed economy (Case 3) where stocks are abundant and animal production is intensive, the analysis must be very precise, identifying the cost of treatment above which this will no longer prove profitable, before any decision is made.
For Cases 2 and 3 it is particularly important to only feed the treated forage to those animals with modest needs, saving the best quality forages for the productive animals.
The development of techniques for fabrication of blocks and for urea treatment should be accompanied by practical demonstrations and trials which allow the collection of field data. These will then effectively serve as solid and complementary data to those originating from experiment stations and will constitute an invalulable tool for the extension officers and decision makers for their efforts in diffusion of the technique at farm level. Support measures, such as building up stocks of necessary inputs (urea, minerals, …) and establishing short term credit schemes allowing their purchase will be essential in order to assure continuity of activities. These measures must in all cases be reinforced by a whole process of training and extension, in cascade, within which the farmer should play a catalytic role for diffusion and adoption of the technique.
The best assurance for farmer adoption of the treatment techniques and for fabrication of the multinutrient blocks will finally depend upon the speed and the perception of the response in terms of definite improvement to animal health and to increases in their productivity.
The introduction of techniques for improving the value of low quality forages constitutes a driving force behind efforts for improving forage production systems. From a more general point of view, it constitutes a focal point for development concerning the rural livestock farmer. It should remain complementary to regional agricultural development programmes aimed at forage improvement and as such, cannot act as a substitute.