GB2131273A - Animal feed block - Google Patents

Abstract

A rigid high protein alkaline animal feed block comprising molasses, finely divided magnesium oxide and legume seed, preferably lupin seeds.

Description

SPECIFICATION High protein animal feed block This invention relates to a high protein animal feed block and in particular a substantially rigid high protein animal feed block comprising molasses, magnesium oxide and legume seeds and to a process for the manufacture thereof.

The term "rigid block" is used herein to mean a feed block which does not undergo any appreciable plastic flow under its own weight and retains its shape over long periods of time in the field exposed to climatic conditions.

It is known in the art that the condition of ruminant animals feeding on low protein content feedstuffs can be maintained by ensuring a supply of non-protein nitrogen. Non-protein nitrogen such as urea provides nutrition for bacteria in the rumen which in turn provide the animal with a source of bacterial protein. As a result, it has become common practice in areas where the natural feedstuffs have a low protein content and in drought areas, to supplement the diet of ruminants with a source of non-protein nitrogen. Feed blocks have proved particularly suitable for this purpose because they enable non-protein nitrogen to be readily incorporated into a palatable product which can be easily handled and which offers the advantage of enabling control of consumption through control of block hardness and palatability.

While animal conditions can be maintained through supply of non-protein nitrogen, in order to promote animal growth, meat production, milk produdtion and fertility, ruminant animals need a supply of protein which will reach the second stomach of the animal. One of the problems in supplying protein to ruminant animals is that much of the protein may be degraded to amino acids in the rumen and as a result is not used to the best advantage of the animal.

Therefore, it would be of considerable benefit to the rural industry to have available a high protein animal feed supplement which was easily handled, palatable, and which supplied natural protein in a form which could by-pass the rumen.

It has now been found that the combination of ingredients comprising molasses, magnesium oxide and legume seeds provides a high protein feed block which is highly palatable to ruminant animals and which provides them with a source of by-pass protein.

Accordingly, the invention provides a rigid, high protein alkaline animal feed block comprising molasses, finely divided magnesium oxide and legume seed.

Any of the sugar containing molasses may be used in the preparation of the compositions of the present invention. Examples of such molasses include cane or blackstrap molasses, sugar beet molasses, converted molasses, wood sugar molasses, hydrosyrup and citrus molasses.

Typically the amount of molasses used in the preparation of the compositions of the present invention ranges from 8 to 70% by weight by weight of the final feed block. Preferably the amount of molasses is in the range of from 20 to 50% by weight of the final feed block.

If the proportion of molasses in the lower part of the range is used from 0 - 50%, by weight of the final feed block, of water may be added to provide a suitable blend mobility when a substantial amount of powders are present. Powders include for example dicalcium phosphate and feed meals. The water may be replaced by any aqueous nutrient such as whey liquids.

The magnesium oxide used to prepare the compositions of the present invention is preferably of a sufficiently active grade that under the reaction conditions it reacts substantially completely with the molasses within a reasonable length of time, for example 6 hours. Whilst pure magnesium oxide may be used the cost of such material is comparatively high. The small amounts of impurities which are normally found in commercialty available grades of active magnesium oxide can be tolerated in the feed blocks prepared by the process of our invention and therefore commercially available grades of magnesium oxide are suitable for use in the process of the invention.

Typical of such commercial grades of magnesium oxide suitable for use in the compositions of the invention are those known as caustic-burned magnesias produced by calcining magnesite, dolomite or magnesium hydroxide at temperatures less than 900"C. Particularly suitable magnesium oxides are "Causmag" grades XLF, AL3 and AL4 ("Causmag" is a trade name of a proprietary brand of magnesium oxide available from Causmag Ore Co Pty Ltd of Young, N.S.W. Australia); standard magnesite MgO types 369, 469 and 569 from Martin Marietta Chemicals, Hung Valley, Marylands, U.S.A.; and "Magox" types 95, 90 and Feed Grade ("Magox" is a trade name of Basic Incorporated, Cleveland, Ohio, U.S.A.).The more active grades of magnesium oxide have a low bulk density but high specific gravity and are obtained by relatively low temperature (around 400"C) calcination of magnesium hydroxide or magnesium carbonate.

Typically the amount of magnesium oxide use in the preparation of the compositions of the present invention ranges from 2 to 30% by weight of the final feed block. Preferably the amount of magnesium oxide ranges from 3 to 15% by weight of the final feed block.

The main source of natural protein used in the compositions of the present invention may be chosen from any of the legume seeds. Suitable legume seeds include lupin, bean and pea. Preferably the legume seeds should be varieties known to be palatable to animals, for example certain strains of lupins are bitter and less palatable than other strains which are sweet flavoured.

The use of legume seeds as the main source of protein in the compositions of the present invention has many advantages. The more obvious advantages include the high protein content of legume seeds, especially in comparison to cereal grains, and the availability of legume seeds at prices which allow the economic manufacture of high protein feed blocks.

In addition to the more obvious advantages, the use of legume seeds as the main source of protein in the feed block compositions of the present invention has some very important and unexpected advantages.

Surprisingly, it has been found that the use of legume seeds enables the preparation of palatable feed blocks containing a very high percentage of protein. For example, whereas only a relatively low proportion of feed meals can be blended into molasses to give a palatable feed block, for example a maximum of around 25% by weight of the composition, very high proportions of legume seeds, for example up to 50% by weight of the composition, may be blended into molasses to give a palatable, high protein content feed block.

Moreover, completely unexpectedly it has been found that the incorporation of high proportions of legume seeds into feed blocks provides a high protein feed block which is highly palatable to animals and which provides ruminants with protein in a form which substantially avoids degradation in the rumen thereby providing the animal with by-pass protein which significantly improves the growth rate and general well being of the animal.

Typically the amount of legume seed used in the preparation of the compositions of the present invention is in the range of from 10 to 50% by weight of the final feed block. Preferably the amount of legume seed ranges from 20 to 40% by weight of the final feed block.

To obtain a high bypass of the protein through the rumen the physical form of the legume seed is important. Finely ground legume seed such as legume flour is unsatisfactory as it is digested to a large extent by the rumen. We have found that if the seed is either whole or broken into relatively coarse fragments then the proportion bypassing the rumen is satisfactory. Crushed or chipped legumes seeds which substantially all pass through a 8 mm screen and which 85% by weight of which are retained by a 2 mm screen have proved satisfactory. Crushing or chipping the seed exposes the interior of the seed to the action of the rumen and increases digestion in the rumen. This may be overcome by treating the broken seed with a chemical capable of denaturing the surface of the seed. We have found a dilute solution of formaldehyde to be satisfactory.

A suitable treatment consists of treating broken seed with a dilute aqueous solution of formaldehyde (say a concentration of 15 - 25% by weight). The amount of formaldehyde added should be from 0.5 - 2.5% by weight of seed preferably from 1 - 1.5% by weight. Excess formaldehyde will prevent the seed from being absorbed efficiently by the animal and too little formaldehyde will allow a high proportion of absorption in the rumen.

The compositions of the present invention may comprise a wide range of additional components which may be of benefit to the animal consuming the feed block and/or aid in the preparation of the feed block. For example, the compositions of the invention may comprise animal medicaments, further animal nutrients and/or agents such as dicalcium phosphate, water, acids and surfactants.

Suitable animal medicaments include vitamins, trace elements, additional sources of magnesium, sources of phosphate, sources of calcium, sources of sodium, sources of sulphur and medicaments for treating animals diseases or killing or repelling animal pests.

Sources of vitamins, trace elements, sodium, sulphur, phosphate, calcium and additional sources of magnesium may be incorporated into the feed blocks of the invention where there is a deficiency of these materials in the available feed or where the animal's state of health would benefit from the ingestion of such therapeutic materials. Animal medicaments suitable for the treatment or prevention of animal diseases or to kill or repel animal pests also may be incorporated into the feed blocks of the invention where such medicaments are required.

Vitamins which may be incorporated into the feed blocks include Vitamin A, preferably in the stabilized acetate form, Vitamin E and Vitamin C. Preferably vitamins are added to the reaction mixture as a slurry with a small amount of water towards the end of the blending operation.

Trace elements which may be incorporated into the feed blocks include trace minerals such as iron, cobalt, copper, zinc and manganese which are preferably added in the form of the sulphate salts.

Iodine as stabilized potassium iodide or ethylene diamine dihydroiodate may also be incorporated into the feed blocks. Preferably trace elements are added to the reaction mixture towards the end of the blending operation.

Other animal medicaments which may be incorporated into the animal feed blocks of the invention include: suitable anthelmintic preparations useful in the prevention or treatment of infestation of animals by parasites including, for example, gastrointestinal parasites, liver fluke and lungworm; suitable preparations which act systemically to kill or repel pests including insect pests such as nuisance flies and endoparasites such as ixodes; suitable growth promoting agents; and other animal medicaments suitable for oral administration.

Suitable animal nutrients include tallow, additional protein and/or carbohydrate sources such as the feed meals including barley meal, blood meal, dried buttermilk, cotton seed meal, linseed meal, meat and bone meal, wheat middlings, soya bean meal, dried whey, liquid whey, peanut meal, rice meal and sunflower meal, carbohydrate sources such as maize germ, roughage, crushed grain, millet seed, molasses cane, wheat dust, sucrose, glucose, fructose and sorbitol and non-protein nitrogen sources such as urea, biuret, methylene diurea, urea phosphate, urea sulphate, crotonylidene diurea and isobutylidene diurea.

To ensure that the block is alkaline, calcium oxide may be used in place of some of the magnesium oxide in the preparation of the compositions of the present invention. However, the use of calcium oxide may lead to difficulties in the control of the reaction temperature and to inferior physical properties in the blocks produced.

Feed blocks wherein the magnesium oxide has been replaced completely by calcium oxide are unsatisfactory as the blocks remain soft even though the pH is above 7.

It has been found that the use of dicalcium phosphate in addition to magnesium oxide and optionally calcium oxide as a hardening agents results in the promotion of block hardening and in increase in the block hardness. It has also been found that the use of dicalcium phosphate in addition to magnesium oxide as a hardening agent allows the minimum amount of magnesium oxide necessary for block hardening to be reduced. Therefore, it is preferred that dicalcium phosphate be used in the preparation of the feed blocks of the present invention.

The nature of the dicalcium phosphate, also known as dicalcium orthophophate, used in the preparation of the preferred feed blocks of the present invention is not narrowly critical. Commercially available grades of dicalcium phosphate are suitable, but preferably finely divided, defluorinated calcium phosphate is used.

Typically the amount of dicalcium phosphate used in the compositions of the present invention is less than 20% by weight of the final feed block. Preferably the amount of dicalcium phosphate used in the preparation of the compositions of the present invention ranges from 2 to 10% by weight of the final feed block.

We have found that in the presence of from 2 to 10% by weight dicalcium phosphate and/or from 2 to 10% by weight calcium oxide,the minimum amount of magnesium oxide required to produce a block of satisfactory physical properties may be reduced to 2% by weight.

Depending upon the end use of the block and thus the required rate of consumption of the block it may be desirable to vary block hardness and palatability. For example, it may be desirable to have a low consumption rate of a therapeutic feed block whereas it is usual to require a high consumption rate of a feed supplement block.

Block hardness may be controlled by varying the block ingredients. For example, by varying the molasses and magnesium oxide content of the block. Block hardness may also be varied by the addition of water to the composition and by the addition of acids, for example organic acids such as acetic acid, propionic acid and butyric acid and inorganic acids such as sulfuric acid and phosphoric acid, to promote block hardening. We have found that the presence of butyric acid in the animal feed blocks of the present invention greatly enhances their acceptance by animals. The reason for the improved palatability of the animal feed blocks of the present invention is not understood but the greatly enhanced acceptance of the feed blocks by animals, and particularly ruminant animals such as sheep and cattle, can be readily demonstrated in the field.

Accordingly, in a further embodiment, the invention provides a process for improving the palatability of animal feed blocks which process comprises incorporating in the said feed block butyric acid or a salt thereof.

The pH of the reaction mixture of our blocks must be greater than 7 and preferably in the range 8 - 11.

Hence the amount of acid added is limited by this constraint. Acid salts may be added, for example sodium sulphate.

Block palatability may be improved by the inclusion of: humectants such as glycerol in order to soften the block surface; surfactants such as alcohol ethoxylates; sweetening agents such as sorbitol and fruit juices; and other additives which are attractive to animals.

While the use of legume seeds as the main source of protein in the compositions of the present invention offers the unique advantages of the preparation of a highly palatable feed block containing a very high percentage of protein, the preparation of such blocks presents certain technical difficulties.

In the past it has been common to utilize finely divided materials in the preparation of molasses feed blocks. Blending such finely divided materials into molasses to form a uniform mixture has presented little if any difficulty and the mixtures so obtained set to give a feed block having uniform composition.

In the compositions of the present invention it has been found that the use of whole or broken legume seeds enables a significantly higher percentage of protein to be incorporated into molasses feed blocks and the protein thus incorporated is a good source of by-pass protein. However, whole or broken legume seeds, for example lupin seeds, bean seeds, pea seeds, are comparatively large in size and they are difficult to blend into the reaction mixture to give a uniform composition and the large seeds tend to separate out when the reaction mixture is transferred to a mould to complete the reaction to give a rigid molasses feed block.

It has now been found that the problem of separation of the legume seeds, which gives rise to a non-uniform molasses feed block, can be overcome by first blending together the legume seeds and the majority of the molasses and then adding and blending in the hardening agents and any other optional ingredients.

Accordingly in a further embodiment the invention provides a process for the manufacture of a rigid, high protein, animal feed block comprising, molasses, finely divided magnesium oxide and legume seed, which process comprises: forming a uniform mixture comprising the legume seeds and at least a major proportion of the molasses at a temperature in the range of from 20"C to 90"C, adding to said mixture a hardening agent comprising finely divided magnesium oxide, and blending the mixture at a temperature in the range 45"C to 95"C for a sufficient length of time to obtain a substantially uniform reaction mixture; optionally blending into the mixture any additional solid or liquid components; blending into the mixture the remainder of the molasses if any transferring said reaction mixture to a mould; and maintaining said reaction mixture in said mould at a temperature in the range 45 - 90"C until the reaction is substantially complete and the reaction mixture becomes rigid.

A preferred feed block composition of the present invention comprises from 20 to 50% by weight of molasses from 2 to 5% by weight of magnesium oxide, from 2 to 10% by weight of dicalcium phosphate, from 0 - 5% by weight of calcium oxide, from 20 to 40% by weight of legume seeds and from 5 to 15% by weight of urea.

In a preferred process a feed block composition of the present invention, the legume seeds and a major portion (51 - 100%) of the molasses are blended together at a temperature in the range of from 20"C to 95"C, preferably 50"C to 540C, to form a thick paste. The hardening agent comprising finely divided magnesium oxide and finely divided dicalcium phosphate is blended into the mixture. Any other insoluble components, for example feed meals, are blended into the reaction mixture. Then the viscosity of the mixture is lowered by blending in any remaining molasses, any water, and any soluble components such as urea, sodium chloride, sodium sulfate, trace elements, vitamins, surfactants and organic or inorganic acids. The mixture is then transferred into a mould.

The temperature must be maintained between 45 and 90"C preferably 75 - 95"C during the setting process until the block is reasonable hard. The presence of urea enables a high level of seed to be included by its effect of reducing the viscosity of the molasses slurry.

Heat is evolved during the the setting process and hence external heating is not required to maintain the desired temperature range. However to avoid the risk of overheating we prefer to use a hot air circulating oven to maintain temperature during the setting process.

The hot air does not have to provide heat to the blocks but has an insulating affect to stop the exposed surfaces of the blocks from cooling and to allow the exotherm to increase the mixture temperature. It also prevents excessive temperatures which can cause swelling, over hardening and ammonia formation due to degradation of the urea.

All blocks can be produced by using partial insulation. The degree of insulation depends on the mixing temperature, the quantity and activity of the magnesium oxide and the conductivity of the mixture. Perfect insulation is not desired since the block will increase quickly in temperature due to the exothermic reaction and require close monitoring to provide a suitable block if the texture is important for a required animal intake. If it is necessary to vary the position of blocks during the insulating period due to a mixture being sensitive to high temperatures for extended periods then the insulating method may prove more costly.

Some heat losses occur with the insulating methods used to maintain the mixture temperature in the range 75 to 950C. The amount of insulation required depends on the ambient temperatures and the proximity of the boxes to air draughts.

The boxes used as moulds may be made from carboard in which case the block may be fed to animals without removal of the box as the animals will eat cardboard without ill effect.

A further preferred feed block composition of the present invention comprises, by weight, from 8 to 15% molasses, from 2 to 5% magnesium oxide, from 2 to 10% dicalcium phosphate, from 0 - 5% of calcium oxide, from 20 to 40% legume seeds and from 30 to 40% liquid whey.

The invention is now illustrated by, but in no way limited to, the following Examples in which all parts are expressed as parts by weight unless otherwise stated.

Example 1 Molasses (2300 parts) and lupin seed (3200 parts) were charged into a jacketed vessel and heated to a temperature of 60"C with stirring to give a uniform mixture in the form of a thick paste. Magnesium oxide (750 parts of "Causmag" AL4), dicalcium phosphate (400 parts) and cotton seed meal (400 parts) were blended into the mixture. Agitation was continued and sodium chloride (300 parts), anhydrous sodium sulfate (200 parts) and trace elements (130 parts) were blended into the reaction mixture.The viscosity of the mixture was then lowered by blending into the reaction mixture urea 700 parts), water (400 parts), "Teric" 12A23 (25 parts; "Teric" is a Registered Trade Mark and "Teric" 12A23 is a nonionic surface active agent prepared by condensing one mole of a linear aliphatic monohydric alcohol of average chain length of 12 carbon atoms with approximately 23 moles of ethylene oxide) and the remaining molasses (1195 parts). The mixture was then run off into moulds in the form of polyethylene film lined cardboard boxes or edible gussetted carboard boxes which were then placed in an oven at a temperature of 70"C. After a period of two hours the reaction was essentially complete, the reaction mixture having become rigid, and the moulds were removed from the oven and stacked to allow them to cool to room temperature. Upon cooling the reaction product was released from the polyethylene film lined moulds in the form of rigid block of uniform consistency. The product in the edible gussetted carbon boxes was used for animal feeding without demoulding.

Example 2 The above procedure was repeated using the following proportions of ingredients: Molasses 3395 parts Lupin Seed 3500 parts Magnesium Oxide 750 parts Dicalcium Phosphate 500 parts Cotton Seed Meal 200 parts Sodium Chloride 300 parts Anhydrous Sodium Sulfate 200 parts Trace Elements 130 parts Urea 700 parts Water 300 parts "Teric" 12A23 25 parts Upon cooling the reaction product was released from the moulds in the form of a rigid block of uniform consistency.

Example 3 Molasses (2300 parts) and lupin seed (3200 parts) were charged into a jacketed vessel and heated to a temperature of 60"C with stirring to give a uniform mixture in the form of a thick paste. Magnesium oxide (750 parts of "Causmag" AL4), dicalcium phosphate (400 parts) and cotton seed meal (400 parts) were blended into the mixture. Agitation was continued and sodium chloride (300 parts), an hydros sodium sulfate (200 parts) and trace elements (130 parts) were blended into the reaction mixture. The viscosity of the mixture was then lowered by blending into the reaction mixture urea (700 parts), water (400 parts), butyric acid (50 parts), "Teric" 12A23 (25 parts) and the remaining molasses (1145 parts).The mixture was then run off into moulds in the form of polyethylene film lined cardboard boxes which were then placed in an oven at a temperature of 70"C.

After a period of two hours the reaction was essentially complete, the reaction mixture having become rigid, and the moulds were removed from the oven and stacked to allow them to cool to room temperature.

Upon cooling the reaction product was released from the moulds in the form of rigid block of uniform consistency.

Example 4 The procedure of Example 3 was repeated using the following proportions of ingredients: Molasses 3345 parts Lupin Seed 3500 parts Magnesium Oxide 750 parts Dicalcium Phosphate 500 parts Cotton Seed Meal 200 parts Sodium Chloride 300 parts An hydrous Sodium Sulfate 200 parts Trace Elements 130 parts Urea 700 parts Water 300 parts Butyric Acid 50 parts "Teric" 12A23 25 parts Upon cooling the reaction product was released from the moulds in the form of a rigid block of uniform consistency.

Examples 5- 11 The procedure of Example 1 was repeated using the proportions by weight shown in Table 1.

TABLE 1 Example Composition f /OJ 5 6 7 8 9 10 11 Molasses 42 32 54 42.5 40 54.5 39.95 Chipped Lupin seeds 33 30 33 30 30 33 33 Magnesium oxide 3 3.5 - 2 - - 6.5 Calcium oxide 3 3.5 3.5 - 6 3.5 Urea 7 11 - 7 7 - 7 Salt 3 5 - 4 6 3 3 Anhydrous sodium sulphate 3 5 - 5 5 - Dicalcium phosphate 3 6 - - - - 6 Phosphoric acid - - 6 6 6 6 "Teric" 12A23 - - - - - - 0.25 Trace Elements - - - - - - 1.3 Water 3 4 - - - - 3 pH of block 8 8 6 6 8 6 7 The chipped lupin seeds had been passed through a 8 mm screen and were 85% retained on a 2mm screen. The chipped seeds were treated with 1.2% by weight of formaldehyde sprayed onto the seed as a 20% aqueous solution and kept in contact with the seed for 24 hours. Excess formaldehyde was removed by an air current prior to use.

Examples 7,8, 10 were acid blocks and gave a soft unsatisfactory block not of our invention. The blocks of Examples 5,6 and 11 were alkaline and were hard and had good physical properties. Example 9 was an alkaline block but was soft and unsatisfactory and not of our invention.

Example 12 The procedures of Examples 1, 2, 5 and 6 were repeated except that the blocks were not placed in an air circulated oven during the setting process.

The blocks were put onto masonite sheets (6 per sheet) on a roller table in single and double stacks. The top stack rested either on another masonite sheet or an open wooden separator. The whole batch was covered by a sheet of bubble plastic (packaging type) which was prevented by canite, wooden or masonite boards from touching the liquid in the open boxes. The plastic was cut to hang down the sides of the stack.

The insulation was removed when the blocks were of a similar hardness to when an oven was used. The blocks were then placed under cooling fans.

In each case satisfactory blocks were obtained.

Example 13 Example 5 was repeated using chipped field peas treated with formaldehyde in place of the lupin seed. The chipped peas were of a similar size range to the chipped lupin seed.

The block was satisfactory.

Examples 1415 The procedure of Example 1 was repeated using the ingredients and proportions shown in Table 2. The blocks in both cases were satisfactory.

TABLE 2 Example Composition (%) 14 15 Molasses 10.2 9 Chipped lupin seed 30 35 Cotton seed meal - 7 Magnesium oxide 7.5 8 Urea 7 Salt 3 3 Anhydrous sodium sulphate 3 3 Dicalcium phosphate 3 4 Whey (40% solids) 36.2 Whey (20% solids) - 30.7 pH of block > 8 > 8 Feeding Trial A The objective of this trial was to compare molasses blocks containing either urea or urea plus protein as a supplement to sheep fed a low quality roughage diet. The level of protein (6.6%) in the roughage diet was sufficient to maintain bodyweig ht of mature sheep and also the protein level was likely to be sufficient to meet the nitrogen needs of the rumen microflora without the need for urea. These dietary levels of protein simulate the levels found in dry summer pastures in Southern Australia.

Eighteen mature wethers housed in metabolism cages were fed a low protein roughage diet of oaten chaff/lucerne chaff (6.4 ME, MJ/kg DM, 1.06 N DM basis) adlibitum. The animals were provided with nil supplement, or with continuous access to a molasses block containing either: (i) urea (7.0%), or (ii) cottonseed meal (20%) + urea (7%), or (iii) lupin seed + urea. (block of example 5) The animals were fed the supplement during a preliminary period of three weeks followed by a three week collection period. Measurement of feed intake, and faecal and urine output were made and samples were obtained daily, then bulked for subsequent nitrogen and dry matter determination.

The results are shown in Table 3.

A significant increase in nitrogen retention (p < 0.05) was observed with sheep fed the lupin block. Slight but non-significant increases in nitrogen retention were recorded for the urea and the cottonseed meal block.

TABLE 3 Urea + Urea + None Cottonseed lupin (control) Urea meal seeds No of animals 6 3 4 5 Mean chaff consumption (g.DM/h/day) 1604 1424 1477 1698 Mean feedblock consumption (g.DM/h/day) - 43.1 52.5 88.3 Dry matter digestibility (%) 58.7 59.6 59.2 60.4 Mean N intake from feed block (NI) (g.N/h/day) - 2.0 3.02 6.35 Mean N retention (NR) (g.N/h/day) 4.21 4.85 5.13 7.78 Efficiency of retention of supplemental N (E) (%) - 32.0 30.5 56.2 E = NR (treatment) - NR (control) x 100 NI (treatment) The slight increases in chaff consumption and dry matter digestibility observed with the lupin seed blocks was non-significant. However the supplemental nitrogen retention efficiency shows that the lupin seed block supplement was utilised with almost double the efficiency of the other two supplements.

Feeding Trial B Feeding trial A provided evidence that lupin seed blocks were utilized efficiently by mature sheep fed a low quality roughage diet. The objective of trial B was to determine the effect of block supplementation on growth rate of weaner sheep fed the same poor quality roughage diet.

Seventy-six crossbred weaner lambs initially weighing 24 kg were allocated treatment on a weight basis.

The animals were housed individually in pens and were fed adlibitum a low quality diet of the oaten chaff and lucerne chaff (90:10) (1.05% N on DM basis) mixture used in Trial A. The animals were fed either a nil supplement or molasses blocks continuously containing either urea (7%) or urea (7%) + cottonseed meal, or urea (7%) + lupin seeds) as used in trial A. Feed intake was recorded daily, block consumption twice weekly and liveweights were obtained weekly over the six week period of the trial.

The results are shown in Table 4.

Supplementation with lupin seed blocks significantly increased liveweight gains. However the increases in liveweight gains given by urea, and urea + cottonseed meal, blocks over the control were non-significant.

Lu pin seed blocks and urea blocks increased chaff intake, and wool growth, slightly but the effects were non-significant.

While the increase in block consumption between the urea + lupin seed blocks and the urea blocks, and between the urea blocks and the urea + cottonseed meal blocks, was non-significant, the increase between the urea + lupin seed blocks and the urea + cottonseed meal blocks was significant.

TABLE 4 Treatment blocks Urea + None Cottonseed Urea + (control) Urea meal lupin seeds No of animals 19 19 19 19 Mean liveweight (kg) Initial 24.5 24.7 24.1 23.7 Final 27.3 28.5 27.9 28.5 increase 2.8 3.8 3.8 4.8 Mean block consumption (g/h/day) - 35.1 28.1 51.0 Mean chaff consumption (g/h/day) 872 900 858 892 Mean wool growth (mg/cm2/day) 0.53 0.57 0.50 0.56

Claims (20)

CLAIMS The claims defining the invention are as follows:

1. A rigid, high protein alkaline animal feed block comprising molasses, finely divided magnesium oxide and legume seed.

2. A block according to claim 1 wherein the amount of molasses ranges from 10 to 70% by weight of the final feed block.

3. A block according to claim 2 wherein amount of molasses is in the range of from 20 to 50% by weight of the final feed block.

4. A block according to anyone of claim 1 to 3 inclusive wherein the amount of magnesium oxide ranges from 2 to 30% by weight of the final feed block.

5. A block according to claim 4 wherein the amount of magnesium oxide ranges from 3 to 15% by weight of the final feed block.

6. A block according to anyone of claims 1 to 5 inclusive where the legume seeds are broken and substantially all pass through an 8mm screen and 85% by weight are retained in a 2 mm screen.

7. A block according to Claims 1 to 6 inclusive wherein the legume seeds are lupin seeds.

8. A block according to anyone of claims 1 to 7 inclusive wherein the amount of legume seed is in the range of from 10 to 50% by weight of the final feed block.

9. A block according to claim 8 wherein the amount of legume seed ranges from 20 to 40% by weight of the final feed block.

10. A block according to claim 8 or 9 wherein the legume seed has been denatured.

11. A block according to anyone of claims 1 to 10 inclusive wherein the block comprises from 20 to 50% by weight of molasses from 2 to 5% by weight of magnesium oxide, from 2 to 10% by weight of dicalcium phosphate, from 0 - 5% calcium oxide, from 20 to 40% by weight of legume seeds and from 5 to 15% by weight of urea.

12. A block according to anyone of claims 1 to 10 inclusive wherein the block comprises 8 - 15% by weight molasses, 2 to 5% by weight of magnesium oxide, 2 to 10% by weight dicalcium phosphate, 0 to 5% by weight calcium oxide, 20 to 40% by weight legume seeds and from 30 to 40% by weight of liquid whey.

13. A process of making a block according to anyone of claims 1 to 12 inclusive which process comprises: forming a uniform mixture comprising the legume seeds and at least a major proportion of the molasses at a temperature in the range of from 20'Cto 90"C, adding to said mixture a hardening agent comprising the finely divided magnesium oxide and blending the mixture at a temperature in the range 45"C to for a sufficient length of time to obtain a substantially uniform reaction mixture; optionally blending into the mixture any additional solid or liquid components; blending into the mixture the remainder of the molasses if any; transferring said reaction mixture to a mould; and maintaining said reaction mixture in said mould at a temperature in the range 45 - 50"C until the reaction is substantially complete and the reaction mixture becomes rigid.

14. A process according to claim 13 wherein the legume seeds and a major portion (51 - 100%) of the molasses are blended together at a temperature in the range of from 20"Cto 95"C, to form a thick paste, the hardening agent comprising the finely divided magnesium oxide and finely divided dicalcium phosphate is blended into the mixture, any other insoluble components, are blended into the reaction mixture, then the viscosity of the mixture is lowered by blending in any remaining molasses, any water, and any soluble components.

15. A process according to anyone of claims 13 or 14 wherein the temperature of the reaction mixture in the mould is maintained in hot air circulated oven.

16. A process according to claims 13 or 14 wherein the temperature of the reaction mixture in the mould is maintained by insulation.

17. A process according to anyone of claims 13 to 16 inclusive wherein a temperature in the setting process is maintained between 75 - 95"C.

18. A block according to claim 1 substantially as described the reference to the example.

19. A process according to claim 13 substantially as described with reference to the examples.

20. A block according to any one of claims 1 to 12 inclusive wherein the block comprises butyric acid or a salt thereof.