CHAPTER X USING HAY AND DRY RESIDUES

Once hay or crop residues have been stored they should be used as carefully and economically as possible. Therefore proper care should be taken: during storage and handling to avoid spoilage and loss; in feeding techniques and livestock management to avoid wastage; and in ensuring that they are used in the context of a balanced feeding system.

If stock are to make the best use of feed, they must be healthy and correctly handled. Apart from routine control of epizootic diseases, internal and external parasites may also have to be dealt with. Such treatments are costly, however, and, unless they are part of local practice, advice should be sought before using them routinely. Housing and shelter are required in some climates to protect livestock against cold, rain or sunshine.

Where hay is grown for sale, there is a choice between selling immediately - even direct from the field - or storing in the hope of high prices later in the year. The choice will depend on local circumstances and farm cash-flow. The case studies from Turkey and India show that hay production for sale is not limited to large-scale farms: small-scale farms make hay, often from natural pasture, for sale to urban and peri-urban areas, even when their own stock have to subsist on straw. Straw is often sold, loose or baled, direct off the field. In India and Pakistan, it is bought for milch and draught stock in towns.

Storage of hay and residues is discussed in Chapters II and IX. Once in store, they must be kept dry and protected from stock, damp and fire. This may require further thatching or covering of stacks (where hay is stored loose) and keeping the storage area clear of loose material. In traditional systems, stacked hay is usually taken from the stack to a barn or store before distribution to stock. If the store cannot hold a whole stack, the remainder left outdoors must be protected from rain and wind by heavy plastic sheeting or a tarpaulin, otherwise the hay will be spoilt, weathered, and possibly blown away. Carting of loose hay and straw to livestock, housed or in the field, must also be done so as to avoid loss. Baled fodder is simpler to handle because the bales are practical units for distribution.

Hay and residues in feeding systems

Hay is a roughage, and is usually far from a complete feed. Even from high-potential crops with modern machinery, the resultant hay is often inadequate to provide a production diet for cattle. The poor nutritive quality of tropical grasses, and therefore of hay from them, was discussed earlier. High quality legume hays made in dry warm climates are usually of high feeding value, but grass hays in more humid climates and from tropical herbage are of lower quality. Straws and stovers are, of course, much poorer feeds than good hay. It follows, therefore, that these dried fodders should be part of a feeding system rather than used alone.

Some analyses of hays and residues are given in tables at the end of this chapter. These make it quite clear that most tropical, and many other, hays, and almost all residues, will always require supplementation when used in production rations. Many would also require it for maintenance. Only some legume hays can provide enough protein to supplement other roughages.

In stall-fed production systems, as in dairying and fattening, the role of hay and straw is relatively simple: they provide bulk in the ration and, according to quality, some energy and protein, but will usually be supplemented with concentrates and, in season, green fodder. Mature work oxen can subsist on very coarse roughages, although they may need some concentrates during hard work. Growing and milking animals are a very different case, as their needs for protein and minerals are high (and in proportion to growth or the milk yield). How the formulation of a ration should be arrived at will be found in the standard textbooks on livestock feeding; it is the overall composition of the ration that matters, and the components are complementary.

Feeding methods

Poor feeding techniques are a common source of wastage: hay is often fed in the field by simply distributing it on the ground, and this can lead to heavy wastage through trampling and contamination. In some situations, feeding on the ground may be unavoidable, but racks should be used wherever possible. Hard standings help avoid contamination, but are expensive. Hay and straw are often fed to overwintering stock for maintenance, so bales are distributed in the field, leading to waste and treading. When dry fodder has to be fed loose in the field, waste will be less if it is distributed little by little so that the stock eat it all and wait for more.

Figure 41. Urban dairy stock which are fed, year-round, on crop residues, green fodder from the hinterland, and concentrates (Lahore, Pakistan)

Long hay and straw should be fed from racks or mangers to reduce wastage and the racks should be designed for the type of animal to be fed. In arid areas, troughs are often built from mud; elsewhere wood, metal or masonry are used. Where buffalo are being fed, troughs must be particularly robust, otherwise the stock will smash them. A lot of wastage from racks and troughs can be avoided if they are lined or covered with weld-mesh to restrict the amount which animals can pull out at one time. The selective feeding habits of sheep are a problem, but mesh over the trough helps. Portable racks, on wheels, are used for field feeding, and should be sited either on hard standing or on a well-drained part of the field, and shifted regularly to reduce damage to the sward.

Standard bales must be opened for feeding. Those made by a slicing-ram baler come apart easily in slices, thus facilitating distribution. Particular care should be taken with wire-tied bales, now rare, to ensure that no pieces of wire (especially short bits) are left in the feed or around the feeding area since, if ingested, they may cause serious illness or death. Big bales are fed from frames made to hold one bale exactly - the bale is placed by front-end loader, the outer covering cut and it is ready to eat (See Figure 42).

Figure 42. Big bales being fed from special frames (Alford, Scotland)

For housed stock, the racks are often fitted above the trough or manger so that any feed which falls from the rack is held in the trough. All stall-fed stock, and here are included stock tethered at the homestead in the open where the climate does not necessitate housing, should receive their feed and fodder in troughs and racks. Feeding off the ground, apart from being wasteful, is a health hazard. Simple feeding systems can be made from locally available materials: wood, brick and stone - or even dried mud in arid places - and are associated with the improvement and intensification of animal production everywhere. Where straw is plentiful, it may be fed ad libitum so that the stock can feed selectively; the rejected straw in such cases is added to the litter or bedding, so less care is necessary in preventing losses from the racks.

Grazing of straw and stover is wasteful where there is an overall scarcity of roughage. When crop residues are in excess of the farm's needs, however, grazing does have the advantages that the stock can feed selectively and costs are low; the disadvantages are trampling and wastage. The leaves are more palatable and have a higher digestibility than the stems (except for rice, where they are similar); grazing stock will generally eat the more digestible leaves and leave the stems. With small cereals, sheep and goats are particularly adept at grazing selectively; large ruminants can graze coarse stovers and sugar cane tops selectively, but have difficulty with straws.

Where the residues are removed from the field at harvest, as in intensive irrigated systems to allow field preparation for the succeeding crop, residues can be fed to stock elsewhere, allowing about twice the amount they might require, permitting them to select (and reject); in this system the residues are not chaffed. Coarse, rejected, residues need not be wasted, for they can thereafter be collected, urea treated and then fed to stock. Selective feeding on straw does not necessarily assure an adequate diet, although it is a considerable improvement on non-selective feeding, so, for productive stock, supplementation should be done as necessary.

Seasonal planning

Fodder conservation should always be done as part of an overall feeding plan for the agricultural year: storing forage during the peak of the production season in order to supply roughage when grazing is scarce or inaccessible to stock. In the planning process, all available feed sources, including cereals and purchased concentrates must, of course be taken into account, as should fluctuations in stock numbers due to breeding, sale and slaughter. The aim should be to conserve a little more than may be required during the year (unless sale is the main objective); a small carry-over can be useful and may serve as a buffer in a bad year but hay and straw deteriorate with time and are not really suitable as medium-term emergency reserves.

Water is essential in all feeding systems and must be in regular supply at all seasons; its availability may dictate the movements of stock at certain times of the year and must be taken into account during planning.

Severe winters at high latitudes mean that livestock must be fed indoors for long periods. Traditionally, large areas of grass were cut for hay in the humid temperate zone, despite only moderate climatic conditions for drying, and this is still common in mountain areas of Europe, where yields are now boosted by chemical fertilizer. In lowland arable areas, silage from sown pasture or cereals has tended to replace hay. Winter feeding of concentrates is common.

In the colder and drier parts of central and northern Asia, both winters and long dry periods limit the availability of green grazing, so hay is traditional. Cultivated fodder, which originated in this region, is widely saved as hay. Concentrate feeding is not limited to the large-scale sector: feeding of cereals in winter, often barley and maize, is common in the traditional pastoral systems of the colder, semi-arid parts of Asia.

In a Mediterranean climate, the long, hot, dry, summer is a period of feed scarcity, but there may also be winter shortfalls in the colder areas. Late spring surpluses can be harvested as hay, which should be of higher quality than stand-over feed; oats and other sown fodders are grown for hay.

In the great irrigated zones of the subtropics, where mainly-stall-fed cattle and buffaloes are very important, there are two marked periods of scarcity: the winter, mid-December to mid-February, and the very hot period of summer, usually late May to mid-July. At those seasons the stock have to rely mainly on straw and stover as roughage, without the usual admixture of green feed. Hay is a minor product despite the great quantity of sown fodder grown, although with the increased urbanization of the dairy industry, the production of dried fodder is increasing. In areas of severe feed scarcity, such as parts of the Himalayan foothills,the very poor hay made after the monsoon is highly sought after for want of other feed, and crop residues may be fed to stock which spend part of the day at "pasture," gleaning what herbage they can from degraded land. The effort put into hay collection and transport, often by porterage, shows that the dried grass is valued, but whether primarily for production or for dung as fuel and manure is unclear.

Figure 43. Buffalo tethered beside loose rice straw; heifer at trough for feeding of other fodders; more valuable fodder is given in the wheeled trough (Punjab, Pakistan)

Chaffing of fodder

Chaff-cutters of the flywheel type are widely used in Pakistan and India for both green feed and stover, and contribute greatly to economy in fodder use by reducing selectivity and permitting thick-stemmed material to be easily eaten. Flywheel cutters consist of a metal frame in which a flywheel with two knives mounted on it spins at speed, the forage is pushed through the wheel by a force feed; the knives, which are easily replaced, are adjustable for angle and must be regularly sharpened with a file or stone. These are sturdy machines, manufactured in large numbers, and simple to maintain and repair by local technicians. Chaffers can be powered by hand, by draught animals (often using the drives of old Persian wheels), by tractor or by electricity. They are used throughout the northern irrigated tracts and are also common in urban areas if cattle are kept. In towns, fodder-chaffing may be a specialized occupation or associated with the local fodder market. Straw in these areas is chaffed during threshing. Stovers are coarse and usually thick-stemmed; where mechanical collection is used, they will usually have been chopped by the pick-up mechanism.

Figure 44. A hand-operated press for baling natural hay (Gujarat, India)

Photo: Ian Lane/C.S. Pandey

Figure 45. A Farmer with lucerne hay in an area of extreme winter feed scarcity

Photo: Dost Mohammad

Hand-harvested material, however, is collected and stored long. In most situations it should be chopped or chaffed before feeding. In India and Pakistan, chaffed stover and straw are mixed with green feed and usually fed in troughs. Uneaten, coarse bits of chopped fodder may be added to dung cakes and so are used as fuel.

Hinged-knife choppers, worked by hand, are very simple machines which are still used in parts of China to chaff fodder and stover, as well as to reduce material for composting. However, although cheap and easy to manufacture, they are slow to use and require a lot of hand labour. Loose, partly chopped hay is ideal for mixing with other ration components and is much less prone to wastage.

Supplementation at pasture

In grazing and pastoral systems, the situation is less clear than for stall-fed production. Supplementary feeding is not additive to grazing. When hay, straw or concentrates fed to grazing stock replace part of the diet formerly grazed, because of substitution, the objective of utilizing pasture to its maximum and supplementing the animals with additional feed cannot be attained. The greater the supplementation, the less forage grazed. Where intake is limited by low availability of forage, the supplementation must take the place of forage.

Figure 46. Cattle being fed hay ad libitum while grazing rich pasture (Dunecht, Scotland)

Where, however, intake or absorption are adversely affected by a deficiency despite a surplus of forage, then a supplement acts as an additive to the diet (e.g., micronutrients, or protein in a deficient diet).

Supplementation may be at several levels and for different reasons: to assure survival, to assure maintenance, or to assure production and reproduction. It can be by providing complete feed or, at pasture, by giving specific nutrients to enable the livestock to consume more of a forage or to digest the same quantity of forage more efficiently, or to overcome a nutrient deficiency per se. Supplementation at pasture with hay or straw need not be because the pasture is poor: hay or straw are sometimes offered to grazing stock when the pasture is very lush, of high moisture or protein content or where there is a danger of bloat in legume-rich swards (Figure 46).

Where the climate allows stock to be outside throughout the year, survival strategies in the traditional sector are often based on allowing stock to lose some weight during the dry or cold season while foraging on what herbage is available, without supplementation. There is often a rapid regain of weight once herbage again becomes available. This gives an uneven or "stepped" weight gain pattern, and stock reach mature weights after several years, but costs and inputs are minimized. In cold climates, some hay may be fed to weak stock to help them survive. In tropical areas, hay is not traditional, but herds may have access to stovers. In some developing countries, especially in Africa, cattle may spend more energy on walking to feed and water than in commercial agriculture. Their grazing time is often restricted by being enclosed at night, since the grazing lands are unenclosed and there is danger of theft or of attack by wild animals. It may sometimes, therefore, be advantageous to offer straw and stover in the night-pen (boma, kraal).

Stock owners are well aware that distribution of hay (and other feeds) reduces foraging by stock, especially when herbage quality is low. When supplementation is fed while the stock are at pasture, it should, generally, be given once they have returned in the evening. An exception is where legume-based pastures are lush and there is danger of bloat; then dry fodder - be it hay or straw - should be given before they go out or, in the case of continuous grazing, be on offer in the field.

In cold semi-arid areas, cattle and yak herders prefer to let their stock graze frozen herbage rather than to feed hay, except to weak stock in order to save their lives and help them reach the following spring. A field visit to Arkhanghai Aimak in Mongolia (see case study) showed that herders are loath to give supplementary feed except to special classes of stock (milking and pregnant animals, saddle and pack horses) because fed animals tend to graze less and come home early to wait for feed. On the Qinghai-Tibet Plateau in China, Cai Li and Weiner report "A little hay is usually made but it is only given to sick or very weak animals (yaks) towards the end of winter" (FAO, 1995b).

Emergency feeding

In feeding for survival during severe drought or food scarcity, the principles are similar to those of stall feeding. Conserved fodder or silage can be used if available, but grain is usually more economical. Hay is usually made in the context of the normal feeding year (and production can rarely be increased ahead of a drought, even if the emergency can be foreseen). Hay reserves are difficult to store for long periods and the cost of transport of hay is high compared to that of more concentrated feeds. Therefore, while a hay bank may be prudent on a farm, when a real drought or emergency happens it is usually more economical to sell as many non-breeding stock as possible and use cereals and other concentrates to help the breeding stock to survive.

Figure 47. Herders prefer to keep supplementary feeding of yaks to a minimum to encourage them to forage (Ikh Tamir, Mongolia)

Even good hay is relatively low in protein; tropical hay and crop residues will usually require additional protein if they are to be useful feeds. Protein supplementation may be in true form from concentrates (plant and animal) or from legumes in fodder banks. It can also be non-protein nitrogen, which can be used by rumen microflora; urea or ammonium bicarbonate are common commercial sources. Both forms of supplementation are most effective when the nitrogen content of the pasture is below that required for satisfactory microbial activity in the rumen and where a source of digestible energy is available. Less soluble "by-pass" proteins can increase intake of feed by ruminants - protein acts as a source of nitrogen and sulphur for rumen microflora, alters the flow rate of digesta and may supply an extra source of amino acids to the tissues. Its net effect is to increase intake of the green feed or concentrate.

Urea-molasses blocks are a source of both non-protein nitrogen and readily available energy: they were originally used to stop weight loss on poor pasture but are now much more widely used to supplement coarse roughages and in integrated feeding systems. The blocks can be made easily with simple hand tools if a cheap source of molasses is available locally, and should be considered wherever protein deficiency is a problem.

While protein is a major consideration at pasture, minerals, especially phosphorus, can be limiting and phosphorus is frequently below maintenance levels in poor hay and dry pasture. Mature, non milking stock in non-deficient areas may be able to pass the lean season on the reserves in their skeleton, but growing stock cannot. The phosphorus content of herbage (and the yield) can be raised by manuring, but phosphorus supplementation of the feed is usually the cheapest approach; sterile bone meal and some inorganic forms, such as di-ammonium phosphate and bi-calcium phosphate, can be used in concentrates or licks.

Feeding for production

Hay rarely provides a production ration on its own; straw and treated straw never do. In order to make full use of them, therefore, supplementation is needed. For moderate to high levels of milk production, oil-cakes, brans and cereal offals will be required. Growing cattle over a year old and work bullocks require only small quantities of supplements if the hay is reasonable or the straw treated. Bos indicus is probably more efficient in maintaining liveweight on low rations in time of shortage than B. taurus, and tropical work oxen (and buffaloes) often grow and work with little or no supplementation. In dry areas with open winters there is usually enough forage for stock to survive, but they lose weight over the dry season. In Australia, some supplement is desirable for stock grazing Mediterranean pastures in summer, tropical winter pasture or cereal stubbles. Grain can be used to maintain weight, or for production if desired.

Feeding values of some dried forages

Some analyses of hays and residues follow, but it should be kept in mind that while mature residues vary a little, the composition of forage that is mown green varies greatly according to the stage of growth of the plant, and the resulting hay will vary according to the climatic conditions at the time of its making and the skill with which it was cured.

Table 9. Analysis of grass hays (values expressed as a percentage of dry matter)

Key to columns: CP = crude protein; CF = crude fibre; NFE = nitrogen-free extract; Ref. = reference source. Reference sources: (1) Topps and Oliver, 1993. (2) Tropical Feeds (FAO, 1993)

Table 10. Feeding value of teff hay in South Africa (as % of DM, except DOM and ME)

Key to columns: (1) = crude protein (CP); (2) = ether extract (EE); (3) = crude fibre (CF); (4) = nitrogen-free extract (NFE); (5) = digestible crude protein (DCP); (6) = digestible organic matter % (DOM); (7) = metabolizable energy (ME; Mj/Kg); (8) = total digestible nitrogen (TDN); (9) = Calcium (Ca); (10) = Phosphorus (P); (11) = potassium (K).

Sources: (12) Bredon, Stewart and Dugmore, 1987. (13) Department of Agriculture, 1995.

Table 11. Analysis of legume and other residues, expressed as percentage of dry matter

Key to columns: CP = Crude Protein; CF = Crude Fibre; NFE = nitrogen-free extract; Ref = reference source. Reference sources: (1) Topps and Oliver, 1993. (2) Tropical Feeds (FAO, 1993).

Table 12. Analysis of legume hays, expressed as a percentage of dry matter

Key to columns: CP = Crude Protein; CF = Crude Fibre; NFE = nitrogen-free extract; Ref. = reference source.

Reference sources: (1) Topps and Oliver, 1993. (2) Tropical Feeds (FAO, 1993). (3) Case studies in this publication.

Table 13. Analysis of some straws and stovers, expressed as a percentage of dry matter

Key to columns: CP = Crude Protein; CF = Crude Fibre; NFE = nitrogen-free extract; Ref = reference source.

Reference sources: (1) Topps and Oliver, 1993. (2) Tropical Feeds (FAO, 1993). (3) Case studies in this publication.

Treatment of crop residues (and poor hay)

The use of ammonia or urea to improve the digestibility of straw and supply some nitrogen has been mentioned in Chapter IX, as has its capacity to act as a conserving agent where proper drying is difficult. The same process can be used with low-quality bush hay. The type of treatment will depend on local circumstances. Ammonia treatment is suitable for large operations in areas where there is a supply of anhydrous ammonia and the necessary infrastructure of tankers to distribute it; it is also suitable for use in cool climates where the enzymatic breakdown of urea would be too slow.

Ammonia treatment is suitable for cooperative and village organization, especially where baled straw is used; this was clearly demonstrated with rice straw at village level in Egypt in the early 1980s (Creek, Barker and Hargus, 1984; Barker et al., 1987). After testing and demonstration, a group straw treatment system was set up. Rice straw is the basis of ruminant feeding in many areas, wheat straw being scarce and very expensive. Farmers pooled their baled straw into large stacks, which were then treated with ammonia. Once treatment was complete the covers were removed and each participant could take his number of bales. Anhydrous ammonia is cheap and readily available locally, as are transport facilities; the climate is such that the treatment is rapid and so dry that, once treated, the straw does not need protection.

Animals should be introduced to eating treated straw over a week or ten days by introducing it gradually, mixed in more and more into the fodder that they are used to. Adaptation is quicker when animals are used to eating straw, and if the treated straw has been aired for some hours before being fed. As soon as the animals eat treated straw readily, it should be fed directly from the stack, not aired beforehand. Treated straw is more palatable and more digestible than untreated, so treatment automatically raises intake. This is, of course, the purpose of the process, but in situations where total dry matter supply is a constraint (which is unfortunately common in some areas), there is no point in treating if all that it will do is cause the supply to run out more quickly. This is debatable: replace because of the improved nutritional value of the straw, but the treated product would have to be carefully rationed.

Dolberg (in FAO, 1995c) indicates that animals can be expected to consume one-third more treated than untreated straw, and recommends the following quantities:

Table 14. Untreated and treated straw feed quantities according to liveweight

Treatment is recommended where straw constitutes over half the diet because better feeds are scarce, or where higher levels of production are aimed at. Farmers are often more interested in treating straw for stock which will give an immediate return, such as for milk or fattening.