15 Feed and Industrial Uses for Cereals Introduction two categories: wheat, oats, rice and sorghum, of The worldwide usage of all the cereals, gathere which about 7% of the entire crop in each case ogether, as revealed in the FAO Food Balance used for industrial purposes, and barley, ch Sheets, is about 4% for seed, and the remainder maize and millet, of which nearly twice as mu almost equally shared between human food use (12-15%)is used industrially (49%)and animal feed plus 'processing and other (principally industrial) use(47%). The last cate- Raw materials used for feed and gory divides into about 37% for animal feed plus industrially 10%for industrial use. There is, however, con The raw materials used for these purposes fal siderable variation among the eight principal into three categories cereals, as shown in Table 15.1 1. The whole grain as harvested or perhaps with a minimum of World U 2. Certain components of the grain which pro- Cereals, 1984-86 average* vide the starting material for chemical process- Processing g These would include starch, for prod Food Feed and other Seed of ethanol, and pentosans, for manufacture of furfural 6.6 3. By-products of the milling process, which are not usually suitable for human food but which 5.378.3 33443.9 8.4 can be used for animal feed and for a wide 3.2 range of industrial uses, including fillers, adhe- 13.9 sives, abrasives. etc, besides the manufacture 11.8 2.7 of furfura Total 49.036.9 Source: FAo Food balance sheets 1984-86. Food and Animal feed Agriculture Organization, Rome, 1990 Apart from usage for human food, animal feed by far the largest use for cereals- both whole Thus, very little rice or millet is used for feed, grains and milling by-products hile over 70% of the entire crops of barley and Thus, in 1986/87, out of a total world produc- oats are so used, with the use of maize and tion of all cereals of 1, 830 million tonnes, 892 sorghum for animal feed not far behind million tonnes(48.7%)were used for animal feed For industrial use, the cereals seem to fall into (USDA, 1987b
15 Feed and Industrial Uses for Cereals Introduction two categories: wheat, oats, rice and sorghum, of which about 7% of the entire crop in each case is used for industrial purposes, and barley, rye, (12-15%) is used industrially. The wor1dwide usage Of all the cereds’ gathered Sheets, is about 4% for seed, and the remainder almost equally shared between human food use (49%) and animal feed plus ‘processing and other’ (principally industrial) use (47%). The last category divides into about 37% for animal feed plus siderable variation among the eight principal cereals, as shown in Table 15.1. together, as revea1ed in the FAo Food Ba1ance maize and millet, of which nearly twice as much Raw materials used for feed and industrially 10% for industrial use. There is, however, con- The raw materials used for these purposes fall into three categories: 1. The whole grain as harvested, or perhaps with a minimum of processing. 2. Certain components of the grain which provide the starting material for chemical processing. These would include starch, for production Cereal Food Feed and other Seed of ethanol, and pentosans, for manufacture of (Yo) (%) furfural. Wheat 66.5 20.2 6.7 6.6 3. By-products of the milling process, which are Barley 5.4 73.1 14.9 6.6 not usually suitable for human food, but which can be used for animal feed and for a wide Oats 5.3 78.3 7.3 9.1 33.4 43.9 14.3 8.4 range of industrial uses, including fillers, adhe- Rye Rice 88.0 1.8 7.0 3.2 Maize 20.7 63.9 13.9 1.5 sives, abrasives, etc., besides the manufacture of furfural. Sorghum 35.2 56.6 6.9 1.3 Millet 74.7 10.8 11.8 2.7 Total 49.0 36.9 9.8 4.3 Agriculture Organization, Rome, 1990. TABLE 15.1 World Usage of the Principal Cereals, 1984-86 average* Processing (Yo) (Oh) Animal feed Apart from usage for human food, animal feed is by far the largest use for cereals - both whole grains and milling by-products. Thus, in 1986/87, out of a total world production of all cereals of 1,830 million tonnes, 892 million tonnes (48.7%) were used for animal feed (USDA, 1987b). * Source: FA0 Food Balance Sheets 1984-86. Food and Thus, very little rice or millet is used for feed, while over 70% of the entire crops of barley and oats are so used, with the use of maize and sorghum for animal feed not far behind. For industrial use, the cereals seem to fall into 302
FEED AND INDUSTRIAL USES FOR CEREALS Maize is easily the most widely used cereal, kind of cereal involved and the proportion of that with about 282 million tonnes being used for cereal in the feed; also on the species of animal animal feed (annually) worldwide in 1984-1986, for which the feed is intended, particularly whether followed by barley(about 127 million tonnes)and for ruminants or for monogastric animals and wheat(about 103 million tonnes)(FAo, 1990). probably also on the stage in the animals life A large proportion of the cereal grains fed to cycle, e. g. thinking of poultry, whether for young animals passes through the hands of animal feed chicks, for broilers, or for laying hens processors’. By way of( xample, of the 5.2 million Some of the treatments applied by animal feed tonnes of wheat used for animal feed in the uk processors to cereal grain, and the resulting 1988/89, 2.87 million tonnes(55%)were used benefits are described below. y animal feed processors (a figure based on returns from compounders only, in Great Britain) Grinding H-GCA, 1990). The remainder, still a consider- able quantity, would presumably have been fed This is the commonest treatment, and relatively directly from the farm to the animals, not via inexpensive. Roller mills or hammer mills may be used but hammer mills are favoured because In the same year, 1988/89, 5.1 million tonnes by choice of a screen of suitable size, the hammer of wheat were used by four millers in the Uk mill can yield ground material of any particular which, besides yielding 3. 954 million tonnes of size from cracked grain to a fine powder. The flour, also produced 1. 132 million tonnes of objective of grinding is to improve the digestibility milling by-products- bran and middlings(fine Coarsely-ground grain is preferred for ruminants offal), most of which would have been used for more finely-ground grain for swine and poultry animal feed. Thus, the total quantity of wheat plus wheat milling by-products used for feeding Soaking animals in the Uk in 1988/89 must have been about 6. 3 million tonnes(NABIM, 1991) Grain may be soaked in water for 12-24 h A similar state of affairs probably exists for followed by rolling, for livestock feeding. The wheat in other countries, and also, to varying soaking softens the grain and causes it to swell extents, for other cereal grains worldwide thereby improving palatability. Processing cereals for animal feed Reconstitution The treatments applied to cereals by animal a process in which grain is moistened to 25- feed processors are both expensive and time- 30%m c and then stored in an oxygen-limiting consuming, and obviously would not be under- silo for 14-21 days. This process is successful taken unless such treatments offered considerable with maize and sorghum, and improves the feed dvantages over the feeding of untreated whole growth ratio for beef cattle grain, and were cost-effective. Both cold and hot dry and wet, mechanical and chemical methods of treatment may be used, with the objectives of Steam-rolling and steam-flaking mproving palatability, avoiding wastage, and Grain is treated with steam for 3-5 min(for encouraging consumption, thus leading to a greater steam-rolled) or for 15-30 min( for steam-iaked) fficiency of food usage and perhaps faster growth. and then rolled between a pair of smooth rollers Other objectives would be to improve digestibility These processes improve the physical texture and and/or nutritive value, to prevent spoilage, soften the grain. Steam-flaking makes thinner and to detoxify poisons and to inactivate anti- flakes than steam-rolling. The heat treatment may nutritional factors improve protein utilization by ruminants. In the The actual treatment used will depend on the steam-flaking process there will be some rupturing
FEED AND INDUSTRIAL USES FOR CEREALS 303 Maize is easily the most widely used cereal, kind of cereal involved and the proportion of that with about 282 million tonnes being used for cereal in the feed; also on the species of animal animal feed (annually) worldwide in 1984-1986, for which the feed is intended, particularly whether followed by barley (about 127 million tonnes) and for ruminants or for monogastric animals and wheat (about 103 million tonnes) (FAO, 1990). probably also on the stage in the animal’s life A large proportion of the cereal grains fed to cycle, e.g. thinking of poultry, whether for young animals passes through the hands of ‘animal feed chicks, for broilers, or for laying hens. processors’. By way of example, of the 5.2 million Some of the treatments applied by animal feed tonnes of wheat used for animal feed in the UK processors to cereal grain, and the resulting in 1988/89, 2.87 million tonnes (55%) were used benefits are described below. by animal feed processors (a figure based on returns from compounders only, in Great Britain) Grinding (H-GCA, 1990). The remainder, still a considerable quantity, would presumably have been fed This is the commonest treatment, and relatively directly from the farm to the animals, not via inexpensive. Roller mills or hammer mills may processors. be used, but hammer mills are favoured because, In the same year, 1988/89, 5.1 million tonnes by choice of a screen of suitable size, the hammer of wheat were used by flour millers in the UK mill can yield ground material of any particular which, besides yielding 3.954 million tonnes of size from cracked grain to a fine powder. The flour, also produced 1.132 million tonnes of objective of grinding is to improve the digestibility. milling by-products - bran and middlings (fine Coarsely-ground grain is preferred for ruminants; offal), most of which would have been used for more finely-ground grain for swine and poultry. animal feed. Thus, the total quantity of wheat plus wheat milling by-products used for feeding Soaking animals in the UK in 1988/89 must have been about 6.3 million tonnes (NABIM, 1991). Grain may be soaked in water for 12-24 h, A similar state of affairs probably exists for followed by rolling, for livestock feeding. The wheat in other countries, and also, to varying soaking softens the grain and causes it to swell, extents, for other cereal grains worldwide. thereby improving palatability. Processing cereals for animal feed Reconstitution The treatments applied to cereals by animal A process in which grain is moistened to 25- feed processors are both expensive and time- 30% m.c. and then stored in an oxygen-limiting consuming, and obviously would not be under- silo for 14-21 days. This process is successful taken unless such treatments offered considerable with maize and sorghum, and improves the feed/ advantages over the feeding of untreated whole growth ratio for beef cattle. grain, and were cost-effective. Both cold and hot, dry and wet, mechanical and chemical methods Steam-rolling and steam-f,aking of treatment may be used, with the objectives of improving palatability, avoiding wastage, and Grain is treated with steam for 3-5 min (for encouraging consumption, thus leading to a greater steam-rolled) or for 15-30 min (for steam-flaked) efficiency of food usage and perhaps faster growth. and then rolled between a pair of smooth rollers. Other objectives would be to improve digestibility These processes improve the physical texture and and/or nutritive value, to prevent spoilage, soften the grain. Steam-flaking makes thinner and to detoxify poisons and to inactivate anti- flakes than steam-rolling. The heat treatment may nutritional factors. improve protein utilization by ruminants. In the The actual treatment used will depend on the steam-flaking process there will be some rupturing
Y OF CEREALS of the starch granules, and partial gelatinization beef cattle, maize is generally fed with another of the starch, resulting in more efficient use of cereal: the greatest benefit comes from combining the feed by slowly digested grains (maize, sorghum) with rapidly digested grains(wheat, barley, high Pelleting moisture maize). A combination of 67% of wheat through a die to make pellets -a form whi q plus 33% of dry-rolled maize gave a 6% comple- Steamed grain is ground and the mass is forced mentary effect as compared with feeding 100% all domestic animals seem to prefer to meal. 75% of high-moisture maize plus 25% of dry- However, pelleted cereals are not recommended rolled grain sorghum or dry maize gained more for ruminants because a decrease in food intake rapidly and used the feed more efficiently than ay ensue. On the other hand, pelleting leads to those fed either grain alone (Sindt et al., 1987) increased consumption by swine and poultry, For cows, a typical diet would contain 41% of possibly because pelleting masks the flavour of high-moisture maize(along with alfalfa and soya- unpalatable ingredients in the diet. Pelleting also bean meal, etc. )(Schingoethe, 1991). grinding improves the utilization of amino acids by swine. cracking or rolling the grains, or steam-flaking The heat used in pelleting may be effective in may improve the digestibility. A calf-grower feed inactivating heat-labile toxins might contain 65% of maize, sorghum or barley, plus 10%of rolled oats and 20% of soyabean meal Popping and micronizing (Morrill, 1991) Typical feeds for early-weaned lambs would In grain that has been popped and then rolled, include 67% of ground shelled maize plus rupture of the endosperm improves utilization of 10% of cottonseed hulls, or 74% of ground ear the starch in the digestive tract. micronizing is a maize plus soyabean meal and supplements ( ely similar process to popping, but uses infrared 1991) radiation for heating the grain For pigs of all ages, maize might provide 85% of the grain in the rations. Use of high-lysine Treatment of high-moisture grain soyabean meal needed The feed grains must be Grain harvested at a relatively high moisture ground, e. g. through a hammer mill with /168 content, e.g. 20-35% m.c., can be chemically in. screen. Finely-ground maize is used more treated to prevent the development of moulds efficiently than coarsely-ground, but very fine during storage, to produce excellent feed grinding, making a dusty meal, is to be avoided Recommended treatment of high-moisture grain The proportion of ground maize in the feed for is with acids, used at a rate of 1.0-1.5%. Such swine at various stages of growth could be 80% acids could be propionic alone, or with acetic or for pregnant sows and gilts, 76% for lactation formic acids. Maize and barley, thus treated, can diets for sows and gilts, 63-71% for young pigs be fed to swine, maize and sorghum to beef cattle 78% for growing pigs, and 84% for finishing pigs (Church, 1991) For feeding poultry, maize, sorghum, wheat Feeding maize to animals and barley are the most important cereals and should be ground and perhaps pelleted Maize(corr n)provided 85% of the cereals fed Pelleting prevents the sorting out of constituents to broilers in the U.S.A. in 1984, with sorghum of the diet, and is recommended for chicks providing 11% and wheat 4%(USDA, 1987a). In and broilers. Pelleting minimizes wastage and 1986, the cereals contributing to the feed for improves palatability. Maize could provide 57% livestock in the U.S. A. were: maize 75%, sorghum of the feed for broiler starters, 62% for broiler 9%, oats 6%, barley 4%, wheat plus rye 6%. For finishers, 45% for chickS, 57% for growers (7-12
304 TECHNOLOGY OF CEREALS of the starch granules, and partial gelatinization of the starch, resulting in more efficient use of the feed by ruminants. Pelleting Steamed grain is ground and the mass is forced through a die to make pellets - a form which all domestic animals seem to prefer to meal. However, pelleted cereals are not recommended for ruminants because a decrease in food intake may ensue. On the other hand, pelleting leads to increased consumption by swine and poultry, possibly because pelleting masks the flavour of unpalatable ingredients in the diet. Pelleting also improves the utilization of amino acids by swine. The heat used in pelleting may be effective in inactivating heat-labile toxins. Popping and micronizing rupture of the endosperm improves utilization of the starch in the digestive tract. Micronizing is a similar process to popping, but uses infrared radiation for heating the grain. Treatment of high-moisture grain Grain harvested at a relatively high moisture content, e.g. 20-35% m.c., can be chemically treated to prevent the development of moulds during storage, to produce excellent feed. Recommended treatment of high-moisture grain is with acids, used at a rate of 1.0-1.5%. Such acids could be propionic alone, or with acetic or formic acids. Maize and barley, thus treated, can be fed to swine, maize and sorghum to beef cattle (Church, 1991). (Cromwell, 1991). Feeding maize to animals Maize (corn) provided 85% of the cereals fed to broilers in the U.S.A. in 1984, with sorghum providing 11% and wheat 4% (USDA, 1987a). In 1986, the cereals contributing to the feed for livestock in the U.S.A. were: maize 75%, sorghum 9%, oats 6%, barley 4%, wheat plus rye 6%. For beef cattle, maize is generally fed with another cereal: the greatest benefit comes from combining slowly digested grains (maize, sorghum) with rapidly digested grains (wheat, barley, highmoisture maize). A combination of 67% of wheat plus 33% of dry-rolled maize gave a 6% complementary effect as compared with feeding 100°/~ dry-rolled maize (Kreikmeier, 1987). Cattle fed 75% of high-moisture maize plus 25% of dryrolled grain sorghum or dry maize gained more rapidly and used the feed more efficiently than those fed either grain alone (Sindt et al., 1987). For cows, a typical diet would contain 41% of high-moisture maize (along with alfalfa and soyabean meal, etc.) (Schingoethe, 1991). Grinding, cracking or rolling the grains, or steam-flaking, may improve the digestibility. A calf-grower feed might contain 65% of maize, sorghum or barley, plus 10% of rolled oats and 20% of soyabean meal (Morrill, 1991). Typical feeds for early-weaned lambs would In grain that has been popped and then rolled, include 67% of ground shelled maize plus 10% of cottonseed hulls, or 74% of ground ear maize plus soyabean meal and supplements (Ely, 1991). For pigs of all ages, maize might provide 85% of the grain in the rations. Use of high-lysine maize would allow a reduction in the amount of soyabean meal needed. The feed grains must be ground, e.g. through a hammer mill with %ti% in. screen. Finely-ground maize is used more efficiently than coarsely-ground, but very fine grinding, making a dusty meal, is to be avoided. The proportion of ground maize in the feed for swine at various stages of growth could be 80% for pregnant sows and gilts, 76% for lactation diets for sows and gilts, 63-71% for young pigs, 78% for growing pigs, and 84% for finishing pigs For feeding poultry, maize, sorghum, wheat and barley are the most important cereals and should be ground and perhaps pelleted. Pelleting prevents the sorting out of constituents of the diet, and is recommended for chicks and broilers. Pelleting minimizes wastage and improves palatability. Maize could provide 57% of the feed for broiler starters, 62% for broiler finishers, 45% for chicks, 57% for growers (7-12
FEED AND INDUSTRIAL USES FOR CEREALS 305 weeks)and developers(13-18 weeks),48% for preferred to one in which ground maize is the laying hens(Nakaue and Arscott, 1991) sole cereal because it results in better plumage For horses 25-39% of the feed could less feather-picking, and less cannibalism. On the cracked maize, along with 45-30% of rolled and other hand the corncob plus maize feed gives a 7-10% of wheat bran(Ott, 1991) reduced egg production and less body-weight By-products of the milling of maize are also gain(Clark and Lathrop, 1953) used for animal feeding. A product known as hominy feed comprises the entire by-product streams from the dry milling of maize. It is a Barley for animal feed relatively inexpensive high-fibre, high-calorie Apart from its use in malting, brewing and material which is high in carotenoids (yellow distilling(c f. Ch. 9), the next most important pigments desirable for chicken feed) and vitamins use for barley is as food for animals, particularly A and D. Hominy feed is an excellent source pigs, in the form of barley meal of energy for both ruminants and monogastric As whole barley contains about 34% of crude animals, in this respect being equal or superior fibre, and is relatively indigestible, the preferred to whole maize. Hominy feed competes with type of barley for animal feeding is one with a other maize by-products-corn gluten feed and low husk content. Low protein barleys are favoured spent brewers' grains as an animal feed. for malting and brewing, but barley of high Hominy feed may partially replace grain in diets protein content is more desirable for animal feed for horses, provided the feed is pelleted(Ott The total digestible nutrients in barley are 991). Gluten feed is recovered from the steeping given as 79%. Digestible coefficients for consti water in which maize is steeped as a stage in w tuents of ground barley are 76% for protein, 80% milling(q v ) After the separation of the germ, for fat, 92% for carbohydrate and 56%for fibre in the wet-milling of maize, and extraction of the(Morrison, 1947) oil, the residue- germ cake-is used for cattle The feeding value of barley is said to be equal feed to that of maize for ruminants(Hockett, 1991) and 85-90% of that of maize for swine( cromwell 1991). For swine, barley can replace all the maize in the feed; indeed barley is preferred to maize The maize cob(corn cob in the U.S. A. is the for certain animals, e. g. pigs. The feeding value central rachis of the female inflorescence of the of barley fo is improved by grinding plant to which the grains are attached, and which pelleting, cubing, rolling or micronizing(Hockett remains as agricultural waste after threshing. As 1991). It is also used extensively in compound about 180 kg of cobs(d b ) are obtained from feeds each tonne of maize shelled, the annual produc For poultry, a feed containing barley and tion of cobs in the U.S. A alone is of the order improved egg production and feed efficiency as of 30 million tonnes compared with either cereal fed alone lorenz Cobs consist principally of cellulose 35%, pen- and Kulp, 1991 tosans 40% and lignin 15%. Agricultural uses for Swine fed barley grew faster and had a more maize cobs, listed by Clark and Lathrop(1953), efficient feed/gain ratio if the barley was pelleted include litter for poultry and other animals; than if fed as meal. Feed for pregnant sows and mulch and soil conditioner; animal and poultry gilts can contain up to 85% of ground barley, up feeds. The feeding value of corncobs is about 62% to 65% for lactating sows, 80% for growing pigs of that of grains. Up to 67% of ground corncobs, and 86% for finishing pigs( Cromwell, 1991) ith 14%of ground shelled maize and some The barley is normally fed either crushed or soyabean meal and molasses-urea provided a as a coarse meal, thereby avoiding wastage that suitable feed for cattle. For poultry, a feed could result from the passage of undigested grains containing corncob meal plus ground maize is through the alimentary tract. The widespread use
FEED AND INDUSTRIAL USES FOR CEREALS 305 weeks) and developers (13-18 weeks), 48% for preferred to one in which ground maize is the laying hens (Nakaue and Arscott, 1991). sole cereal because it results in better plumage, For horses, 25-39% of the feed could be less feather-picking, and less cannibalism. On the cracked maize, along with 45-30% of rolled and other hand, the corncob plus maize feed gives a 7-10% of wheat bran (Ott, 1991). reduced egg production and less body-weight By-products of the milling of maize are also gain (Clark and Lathrop, 1953). used for animal feeding. A product known as hominy feed comprises the entire by-product Barley for animal feed streams from the dry milling of maize. It is a relatively inexpensive high-fibre, high-calorie Apart from its use in malting, brewing and material which is high in carotenoids (yellow distilling (c.f. Ch. 9), the next most important pigments desirable for chicken feed) and vitamins use for barley is as food for animals, particularly A and D. Hominy feed is an excellent source pigs, in the form of barley meal. of energy for both ruminants and monogastric As whole barley contains about 34% of crude animals, in this respect being equal or superior fibre, and is relatively indigestible, the preferred to whole maize. Hominy feed competes with type of barley for animal feeding is one with a other maize by-products - corn gluten feed and low husk content. Low protein barleys are favoured spent brewers’ grains - as an animal feed. for malting and brewing, but barley of high Hominy feed may partially replace grain in diets protein content is more desirable for animal feed. for horses, provided the feed is pelleted (Ott, The total digestible nutrients in barley are 1991). Gluten feed is recovered from the steeping given as 79%. Digestible coefficients for constiwater in which maize is steeped as a stage in wet- tuents of ground barley are 76% for protein, 80% milling (q.v.). After the separation of the germ, for fat, 92% for carbohydrate and 56% for fibre in the wet-milling of maize, and extraction of the (Morrison, 1947). oil, the residue - germ cake - is used for cattle The feeding value of barley is said to be equal feed. to that of maize for ruminants (Hockett, 1991) and 85-90% of that of maize for swine (Cromwell, 1991). For swine, barley can replace all the maize in the feed; indeed, barley is preferred to maize Maize cobs The maize cob (corn cob in the U.S.A.) is the for certain animals, e.g. pigs. The feeding value central rachis of the female inflorescence of the of barley for pigs is improved by grinding, plant to which the grains are attached, and which pelleting, cubing, rolling or micronizing (Hockett, remains as agricultural waste after threshing. As 1991). It is also used extensively in compound about 180 kg of cobs (d.b.) are obtained from feeds. each tonne of maize shelled, the annual produc- For poultry, a feed containing barley and maize tion of cobs in the U.S.A. alone is of the order improved egg production and feed efficiency as of 30 million tomes. compared with either cereal fed alone (Lorenz Cobs consist principally of cellulose 35%, pen- and Kulp, 1991). tosans 40% and lignin 15%. Agricultural uses for Swine fed barley grew faster and had a more maize cobs, listed by Clark and Lathrop (1953), efficient feed/gain ratio if the barley was pelleted include litter for poultry and other animals; than if fed as meal. Feed for pregnant sows and mulch and soil conditioner; animal and poultry gilts can contain up to 85% of ground barley, up feeds. The feeding value of corncobs is about 62% to 65% for lactating sows, 80% for growing pigs of that of grains. Up to 67% of ground corncobs, and 86% for finishing pigs (Cromwell, 1991). with 14% of ground shelled maize and some The barley is normally fed either crushed or soyabean meal and molasses-urea provided a as a coarse meal, thereby avoiding wastage that suitable feed for cattle. For poultry, a feed could result from the passage of undigested grains containing corncob meal plus ground maize is through the alimentary tract. The widespread use
TECHNOLOGY OF CEREALS of barley by pig feeders is related to its effect on to animals, viz. not via a feed processor, could the body fat, which becomes firm and white if include parcels that did not meet these standards the ration contains a large amount of barley meal and also wheat that was unfit for milling 1953) When wheat was fed to cattle, the efficiency of chiproly'(i. e. hi-pro-ly) barley is a mutant two- feed usage was greater for dry-rolled wheat than row barley from Ethiopia containing the 'lys,' for wholewheat. Dry milling increased grain gene, which confers high lysine content(cf. p. digestibility from 63 to 88%. Further processing, 71). Hiproly barley contains 20-30% more lysine e.g. steam-flaking or extruding, gave no further than is found in normal barley High-lysine barley improvement(Church, 1991). For beef cattle has been shown to improve the growth rate of wheat is best used in combination with other feed pigs(Hockett, 1991). A recent high-lysine barley grains, e.g. maize or grain sorghum. a blend of mutant originating in Denmark is Riso 1508, with 67% wheat plus 33% dry-milled maize improved 50% more lysine than in Hiproly barley. Risg feed efficiency as compared with either wheat or 1508 is intended to provide a feedstuff with an maize alone (Ward and Klopfenstein, 1991) improved amino acid balance for the pig and dairy When fed to finishing lambs for market, wheat industries, one objective being to avoid the neces- had 105% of the feeding value of shelled maize sity of feeding fishmeal, which gives a taint to when the wheat comprised up to 50% of the total he product grain(Ely, 1991).For By-products from the dry milling of barley to food, but is often too expensive. Wheat is similar make pearl barley are used for animal feed, to maize on an energy basis, but has a higher con particularly for ruminants and horses, as con- tent of protein, lysine, and available phosphorus, tituents of compound feeds. brewers'grains and and wheat can replace all or part of the maize in distillers'dried grains are by-products from the the diet for pigs. Non-millable wheat, damaged brewing and distilling industries that can be moderately by insects, disease, or containing incorporated in feeds for ruminants; they are too garlic, can be fed to swine( Cromwell, 1991) fibrous for pigs and poultry For feeding poultry, wheat should be ground and preferably pelleted, to avoid sorting out of Wheat for animal feeding feed constituents by the birds. For poultry, the feed efficiency of wheat is 93-95% of that of maize The animal-feed use of wheat 1980-1984, (Nakaue and Arscott 1991) world-wide, averaged 19.8 million tonnes per Wheat milling by-products- bran and midd- annum. In the U.S. A. alone in 1988/89, 270 lings provide palatable food for animals. million bu(about 7. 35 million tonnes)were used Wheat middlings can replace grain in the feed for livestock feed. The use of wheat for animal provided the diets are pelleted -otherwise they feed is influenced by price, location and nutrient are too dusty. The energy of wheat middlings value(Mattern, 1991) utilized better by ruminants than by monogastric The importance of wheat as an animal feedstuff animals. Cows fed rations containing 60% of is further illustrated by the establishment, by the concentrate did well if 40% of the concentrate Home-Grown Cereals Authority, in the U. K, of was wheat middlings; sv% of the maize in the quality specifications for 'standard feed wheat,, middlings replaced up in association with the National Farmers'Union rations. Middlings are also fed to poultry. Wheat and the U. K. Agricultural Supply Trade Associa- bran is the favoured feedstuff for horses and for tion,in 1978, and subsequently updated. These all ruminants( Church, 1991) quality specifications, which apply to grain destined for the feed compounder, mention moisture con- tent(max. 16%)and content of impurities Oats for feeding animals ergot, max0.05%; other cereals 5%; non-grain The usage of oats for livestock feeding in the impurities 3%(H-GCA, 1990). Wheat fed directly U.S.A. in 1986 was 9.6 million tonnes, exceeding
306 TECHNOLOGY OF CEREALS of barley by pig feeders is related to its effect on the body fat, which becomes firm and white if the ration contains a large amount of barley meal (Watson, 1953). ‘Hiproly’ (i.e. hi-pro-ly) barley is a mutant tworow barley from Ethiopia containing the ‘Zys’ gene, which confers high lysine content (cf. p. 71). Hiproly barley contains 2630% more lysine than is found in normal barley. High-lysine barley has been shown to improve the growth rate of pigs (Hockett, 1991). A recent high-lysine barley mutant originating in Denmark is Riso 1508, with 50% more lysine than in Hiproly barley. Riso 1508 is intended to provide a feedstuff with an improved amino acid balance for the pig and dairy industries, one objective being to avoid the necessity of feeding fishmeal, which gives a taint to the product. By-products from the dry milling of barley to make pearl barley are used for animal feed, particularly for ruminants and horses, as constituents of compound feeds. Brewers’ grains and distillers’ dried grains are by-products from the brewing and distilling industries that can be incorporated in feeds for ruminants; they are too fibrous for pigs and poultry. Wheat for animal feeding world-wide, averaged 19.8 million tonnes per annum. In the U.S.A. alone, in 1988/89, 270 million bu (about 7.35 million tonnes) were used for livestock feed. The use of wheat for animal feed is influenced by price, location and nutrient value (Mattern, 1991). The importance of wheat as an animal feedstuff is further illustrated by the establishment, by the Home-Grown Cereals Authority, in the U.K., of quality specifications for ‘standard feed wheat’, in association with the National Farmers’ Union and the U.K. Agricultural Supply Trade Association, in 1978, and subsequently updated. These quality specifications, which apply to pain destined for the feed compounder, mention moisture content (max. 16%) and content of impurities - ergot, max. 0.05%; other cereals 5%; non-grain impurities 3% (H-GCA, 1990). Wheat fed directly to animals, viz. not via a feed processor, could include parcels that did not meet these standards and also wheat that was unfit for milling. When wheat was fed to cattle, the efficiency of feed usage was greater for dry-rolled wheat than for wholewheat. Dry milling increased grain digestibility from 63 to 88%. Further processing, e.g. steam-flaking or extruding, gave no further improvement (Church, 1991). For beef cattle, wheat is best used in combination with other feed grains, e.g. maize or grain sorghum. A blend of 67% wheat plus 33% dry-milled maize improved feed efficiency as compared with either wheat or maize alone (Ward and Klopfenstein, 1991). When fed to finishing lambs for market, wheat had 105% of the feeding value of shelled maize when the wheat comprised up to 50% of the total grain (Ely, 1991). For pigs, wheat is an excellent food, but is often too expensive. Wheat is similar to maize on an energy basis, but has a higher content of protein, lysine, and available phosphorus, and wheat can replace all or part of the maize in the diet for pigs. Non-millable wheat, damaged moderately by insects, disease, or containing garlic, can be fed to swine (Cromwell, 1991). For feeding poultry, wheat should be ground, and preferably pelleted, to avoid sorting out of feed constituents by the birds. For poultry, the feed efficiency of wheat is 93-95% of that of maize Wheat milling by-products - bran and middlings - provide palatable food for animals. Wheat middlings can replace grain in the feed, provided the diets are pelleted - otherwise they are too dusty. The energy of wheat middlings is utilized better by ruminants than by monogastric animals. Cows fed rations containing 60% of concentrate did well if 40% of the concentrate was wheat middlings; swine did well when wheat middlings replaced up to 30% of the maize in the rations. Middlings are also fed to poultry. Wheat bran is the favoured feedstuff for horses and for all ruminants (Church, 1991). Oats for feeding animals The usage of oats for livestock feeding in the U.S.A. in 1986 was 9.6 million tonnes, exceeding The animal-feed use of wheat 1980-1984, (Nakaue and Arscott, 1991)