The present invention relates to a product and method for providing high nutrient feed to ruminant animals. In particular, the present invention relates to pelletized high nutrient feed that will be readily consumed by ruminant animals, and particularly cattle, subjected to a feedlot cereal grain fed environment or other high grain usage environment, such as in drought supplementing, without causing digestive tract complications. BACKGROUND ART

Conventionally, cattle fed in a feedlot environment have had nutritional supplements added to their feed mix or ration in the form of a variety of powdered or crumbled pre-mixes. Such powdered or crumbled supplement pre-mixes, once mixed in with the feed ration, were generally unstable and inconsistent and, over time, settled to the bottom of the feed ration, particularly as the cattle sifted through the feed, thereby denying a full supplement intake by the cattle and the ratio of grain to supplement changed from the specified diet regime.

There is a need, therefore, for a carrier for the nutritional supplements that can be added to the feed ration and remain evenly distributed therein even during cattle feeding. The carrier should be stable and be able to preserve the nutritional characteristics of the supplements so that the cattle would receive an adequate periodic intake of the nutritional supplements in a ratio

that was consistent with their intake of the total feed ration.

Another common problem with conventional feedlot feed rations is based on the use of urea as a concentrated source of nitrogen. Urea is hydroscopic and so readily attracts moisture from the atmosphere and surrounding environment. This can cause the feed ration, as well as the urea itself, to harden by the components of the ration packing or binding together. This will adversely affect the quality of the feed in the ration.

Urea also has the disadvantage that it can cause corrosion of mixing machinery and other equipment that comes into prolonged contact with it.

The urea component of the feed ration should therefore be substituted by a nitrogen source replacement that will not be hydroscopic and cause hardening of the feed ration and corrosion of valuable equipment.

A further problem associated with conventional feedlot feed rations has centred on the difficulty with which cattle digest cereal grains and the digestive tract complications that occur as a result of the intake of this high starch food source. Traditionally, the cattle are gradually introduced to increasing levels of cereal grain in their feed ration so as not to trigger grain poisoning or acidosis brought about by a build up of lactic acid in the rumen and not to inhibit fibre digestion which may result with the sudden advent of grain feeding. Incorporating roughage into the feedlot ration has also

been used to control the effect of acidosis in cattle. However, the use of roughage is laborious and requires expensive capital equipment.

Furthermore, the time taken to gradually introduce the cattle to a grain based diet is costly and means that the cattle will not be in their most productive state until they have completely adjusted to the new feeding regime. It would be advantageous if a more immediate way was found to overcome the problems associated with adjustment to a cereal grain diet.

It is therefore an object of the present invention to provide a product that can be included into the feed mix or ration of ruminant animals subjected to a cereal grain based diet, such as in cattle feedlots or other grain feeding regimes, that will:-

(i) provide a high nutrient supplement to the feed ration, (ii) remain evenly dispersed throughout the ration, (iii) maintain its nutritional characteristics over a prolonged period,

(iv) serve as a concentrated source of nitrogen for protein synthesis and so replace urea, and (v) avoid the onset of acidosis and the requirement for roughage to be included in the diet regime. It has been found by the present inventor that these objects can be achieved with the use of a high nutrient pellet that provides a concentrated nitrogen source and

contains an antibiotic that targets bacteria that produce lactic acid in the rumen. SUMMARY OF THE INVENTION

According to the invention there is provided a high nutrient pellet for inclusion in the feed ration of ruminant animals fed on high cereal grain diets, the pellet including:-

(i) a carrier material that serves as a concentrated source of protein and other essential nutrients, and

(ii) an antibiotic that will inhibit lactic acid production in the rumens of the said animals. Preferably, the carrier material is cereal pollard and bran and the antibiotic is Virginiamycin. According to another aspect of the invention there is provided a method for feeding ruminant animals subjected to a high cereal grain diet, the method including adding to the diet a high nutrient pellet which includes:-

(i) a carrier material that serves as a concentrated source of protein and other essential nutrients, and (ii) an antibiotic that will inhibit lactic acid production in the rumens of the said animals. DESCRIPTION OF PREFERRED EMBODIMENT In order that the invention may be more readily understood and put into practical effect, reference will now be made to both conventional feedlot methods and to preferred embodiments of the invention.

A conventional feedlot feed mix or ration for cattle or sheep typically consists of:- 16% hay or filler, 64% cereal grain, 20% high concentrate pre-mix of supplements, such as vitamins, minerals, proteins etc. which offer synergistic benefits with hay and grain for animals' health and weight gain. With specific reference to cattle, cattle gain about 1 kg liveweight for every 8 kgs of feed eaten on a good feed mix in a feedlot environment.

The range varies on each side of this ratio depending on the quality of the grain and the make up of the pre-mix, together with an effective veterinary control practice and a manager's general know how.

The economics are that a kg of total feed mix costs between 10.75c per kg to 17.5c per kg. Therefore a weight gain ratio on 8 kgs of feed to 1 kg of weight gain gives a cost per kg of weight gain of between 80c to $1.40, with finished cattle selling in a range of between $1.15 per live kg to $1.60 at the moment.

A cattle feedlot operation is very sensitive to the weight gain efficiency of feed eaten and the cost of that feed. It is an operation that works on high volume and low margins, with a mortality risk factor of between 0.5% to 1% being acceptable according to industry standards.

The benefits of supplements, such as vitamins, and anti-bacterials are also assisting the health regime of a

feedlot and are keeping the mortality rate low, as well as giving greater conversion efficiency of feed eaten to weight gained.

These benefits may be enhanced and a greater efficiency may result with the use of a pellet that retains all the nutritional supplements that are required to make up a good total feed mix and which can be present in the feed mix in even suspension so as to be optimally available to animals. The economic benefits of having a high nutrient pellet are:-

(i) increased feed conversion efficiency, thereby decreasing the cost per weight gained, (ii) it allows a higher cereal grain diet to be fed, so increasing weight gain and decreasing time in feedlots,

(iii) it increases the total cost effectiveness of feeding cattle (and sheep) in a feedlot environment, and (iv) it controls mortality rate. Pollard and bran, when the admixture of supplements is added, readily serves as a carrier for the supplements in the pellet. Carried in the pellet form, the supplements are therefore evenly distributed with the bulk grain and/or hay of the total feed mix. The supplements are easily added and mixed through a revolving agitation process similar to a cement mixing apparatus.

The pollard and bran has a high protein level of about

16% and so is able to replace urea. Pollard and bran is the skin of wheat or the fibrous part left over after extraction of flour etc. and is approximately 25% of the volume of wheat. Millrun, as it is commonly called in the industry, contains approximately 33% bran and approximately 66% of pollard. The pellet of the invention preferably contains between 50% and 90% w/w of bran and pollard. It has been trialled at various ratios of total feed mix and it has been found that from approximately 7% to 15% w/w of total feed mix it is particularly effective. It is also effective from about 4% to 33% w/w of the total feed mix. The pellet may include the following components:- (i) cereal pollard, and pollard and bran (from wheat, barley, oats, lupin, rice, triticale, rye, ryecorn and the like) ,

(ii) offal that remains as a by-product from the primary and secondary processing of all oilseeds and legumes, including but not limited to: oilseed, canola, rapeseed, linseed, sunflower, cotton seed, soybean, legumes, lupins, chick peas, field peas, lentils, faba beans and the like, (iii) by-products or waste remaining from the processing of fruit and vegetables such as citrus peel, apple pulp, pineapple pulp, pea pulp, tomatoes and the like, (iv) waste from horticultural production such as graded out or undersized or oversized produce

such as potatoes or tomatoes, (v) waste or by-products from sugar cane processing or sugar refining products such as molasses and bagasse, (vi) mineral products such as bentonite, salt, lime and crushed lime, (vii) the lignocellulosic sources such as cereal straw residue left after grain harvest, timber legume or sap from plants and trees. Other products not listed above could be used as a suitable carrier in pellet form of the supplement pre-mix and/or combined pre-mix and anti- bacterial products for the purpose of cereal grain feeding of ruminant animals.

The pellet does not break up, dust off, or move through the total feed mix to the bottom of the feed trough, and one can be sure the additives in the pellet are stable and properly rationed to the animals in the whole diet as prescribed for a nutritional total feed.

The functional benefits of using a pellet such as that described above as the carrier form for the nutritional supplements for a feedlot ration are as follows:-

(a) it provides an even distribution of high value supplements in the initial feed mix,

(b) it includes a source of nitrogen to replace the corrosive substance urea, where urea might otherwise be used,

(c) the pellet is an ideal carrier form for the

nutritional supplements, and it is easy and effective to use, (d) it negates the requirement of feeders to have on hand a plethora of nutritional admixtures, and (e) it is time and labour saving.

The addition of the antibiotic Virginiamycin to the pellet allows cereal grain to be fed safely to ruminants as Virginiamycin stops the bacteria that make lactic acid and cause acidosis, brought about by the high starch levels in cereal grains.

Virginiamycin is an antibiotic with specific activity in the digestive tract of animals against rumen bacteria. In cattle and sheep, the antibiotic specifically targets rumen bacteria that produce lactic acid and thus affords protection against acidosis or grain poisoning in cattle and sheep that have not adjusted/or have been introduced to eating cereal grain. Lactic acid production is also a problem in cereal grain fed cattle because it inhibits fibre digestion. Virginiamycin therefore reduces production of lactic acid making the cereals safer to eat and reducing the need to gradually introduce stock to grain. Another feature of Virginiamycin is that it works in the digestive tract and very little is absorbed into the animal's bloodstream. The pellet of the invention provides producers with a simple means of delivering the antibiotic evenly in a ration, and even distribution is a large factor in determining its effectiveness.

In regard to "opportunity feedlots", which are those feedlots set up for temporary periods only when conditions are appropriate, such as in drought or when cost of cattle or grain is low, the Virginiamycin incorporated pellet will allow these types of feedlots to operate more effectively and will reduce some capital costs. Traditionally, acidosis is controlled by incorporating roughage in the diet and by gradually adapting cattle to increased levels of grain. The incorporation of roughage is laborious and requires expensive capital equipment. The use of

Virginiamycin in the pellet means roughage does not need to be incorporated in the ration and in fact does not need to be fed at all. One hundred percent cereal grain may, therefore, be fed with safety, given no abnormal factors exist.

In regard to "professional feedlots", which are those feedlots set up for continuous, long term operation, there exists the problem of non-productive introductory periods where cattle are introduced to increasing levels of cereal grain. Performance is always reduced during this period.

The use of Virginiamycin in the pellet will allow cattle to be introduced directly to high cereal grain diets thereby eliminating the relatively unproductive introductory period. The period of the feeding regime needed for "finishing" the cattle can therefore be reduced resulting in substantial savings, particularly on short feeding regimes (for example, for domestic specification product). The pellet of the invention may reduce an 80 day feeding

program to, for example, a 70 day feeding program, saving some ten days of feed and associated costs.

Supplementary feeding with cereal grain has always been a problem as the grain, once consumed, produces lactic acid which inhibits the digestion of fibre which is another important component of the diet. Eliminating lactic acid production through the use of the pellet of the invention will result in supplementary feeding with grain being more beneficial, and easier. It will mean that grain can be fed less often (once a week instead of every two days or so) .

The pellet of the invention may be formed by extrusion, pressing and cube forming or by similar methods. Pressure and heat conditions for forming the pellet will depend on the composition of the pellet and the desired physical characteristics for the pellet. When a pellet press is used, the components are introduced as a powder, mixed in a mixing tank, forced through a dye with the addition of steam and are released as pellets. Such pellets may be of cylindrical shape, approximately 5 to 10 ml in diameter, and approximately 10 ml to 20 ml in length.

A particularly preferred method of manufacturing the pellet of the invention is as follows.

All ingredients are placed in a mixing tank and thoroughly mixed for approximately 10 to 20 minutes to guarantee thorough and even distribution of all ingredients. The mixture consists of a pre-mix of supplements and additives, with bran and pollard being the medium or carrier for Virginiamycin and concentrated source

of nitrogen in the form of protein. When mixed, the ingredients then pass by way of augers from the mixing tank to the pellet press. The mixture then passes through a set of rollers before steam is added and the mixture is extruded through a dye base plate with many holes in it (dyes can have holes of varying sizes) . The dye used in these trials had 5 ml holes in it. After the extruded mixture passes through the dye at between 80°C and 120°C (heat caused from steam and pressure) it is then cooled by way of an air cooler to prevent sticking together of the formed pellets that might occur during drying. Pellets are then augured or blown into a holding tank to be either bagged or bulk loaded onto trucks and the like.

The oil content of the pellet will be typically between 7% to 29% and the pellet may contain an oil diluting substance to facilitate the free movement of the components of the pellet through the extruding process or similar means.

There may be included in the composition of the pellet a thermal bonding agent that ensures that the compressed and formed pellets retain their shape after extrusion. The pellets may be in the shape of cubes, wafers, crumble or granules.

The pellet may also include release agents that ensure no sticking of the compressed pellet to the manufacturing machinery.

A typical composition of a pellet of the invention may be as follows:-

EXAMPLE 1

COMPONENT WEIGHT FOR WEIGHT %(W/W)

Bran/Pollard (Mill run) 88.25

Pre-mix supplement 0.5 Virginiamycin 0.001

Lime 5.0

Bentonite 2.5

Salt 1.25

Canola meal 2.499 The above pellet was used incorporated in a total feed mix at a rate of 200 kg per 1 tonne of total feed mix, so that the pellet is present at 20% w/w of the total feed mix.

The above pellet may also include rumen modifiers to facilitate feed utilization in the rumen and augment the activity of the vitamin and mineral pre-mix supplement.

These modifiers may be included in the pre-mix supplement.

A preferred rumen modifier is MONENSIN, commonly known as

RUMENSIN (trade mark). The pre-mix supplement is as supplied by Rhone Poulenc.

Canola meal is preferably used in the pellet as a protein supplement although other protein meals, such as cotton seed meal, may also be used. Canola meal provides approximately 36% protein and contains approximately 12% oil.

The pellet of the invention may be fed at levels varying from about 4% w/w to about 33% w/w of the total feed mix or ration.

It is recommended that the pellet of the invention contain an amount of Virginiamycin that, when mixed with the total feed, will be present at a concentration of about 20 grams per tonne of feed.

Aside from the pellet, the remainder of the feed ration may include about 95% grain and 5% roughage, with additional roughage being at all times available in racks.

The following are additional examples of pellet compositions suitable for administration in a total feed at varying w/w % ranges. The amount of Virginiamycin (Vn) is not shown separately, but is included in the pre-mix supplement in an amount so that, when the pellet is mixed with total feed, the Virginiamycin will be present at the recommended concentration of about 20 grams per tonne of feed.

EXAMPLE 2

COMPONENT WEIGHT FOR WEIGHT %(W/W)

Bran/Pollard 41.25

Pre-mix (Vn) 2.5

Lime 25

Salt 6.25

Cotton seed/Canola meal 25

The pellet preparation of above Example 2 was used in an amount of 40 kg to 1 tonne of total feed mix, so that the pellet is present at 4% w/w of the total feed mix.

EXAMPLE 3

COMPONENT WEIGHT FOR WEIGHT %(W/W)

Bran/Pollard 53

Pre-mix (Vn) 2.0

Lime 20

Salt 5.0

Cotton seed/Canola meal 20

The pellet preparation of above Example 3 was used in an amount of 50 kg to 1 tonne of total feed mix, so that the pellet is present at 5% w/w of the total feed mix.

EXAMPLE 4

COMPONENT WEIGHT FOR WEIGHT %(W/W)

Bran/Pollard 76.5

Pre-mix (Vn) 1.0

Lime 10

Salt 2.5

Cotton seed/Canola meal 10

The pellet preparation of above Example 4 was used in an amount of 100 kg to 1 tonne of total feed mix, so that the pellet is present at 10% w/w of the total feed mix.

EXAMPLE 5

COMPONENT WEIGHT FOR WEIGHT %(W/W) Bran/Pollard 92.95 Pre-mix (Vn) 0.3

Lime 3.0

Salt 0.75

Cotton seed/Canola meal 3.0

The pellet preparation of above Example 5 was used in an amount of 330 kg to 1 tonne of total feed mix, so that the pellet is present at 33% w/w of the total feed mix.

The use of the pellet of the invention to supply high grain levels to cattle has proved successful and economical. It has been found that the cattle "finish" or are ready for market more quickly when their feed ration includes the pellet of the invention. Some of these cattle have adjusted to a 92% grain diet within eight days of introduction on a 70% to 80% grain diet. Normally, it would be expected that cattle fed conventional high grain diets would take about 25 days, weather permitting, to reach a level of only 80% grain diet.

Various modifications may be made in details of pellet composition and methods for forming same without departing from the scope or ambit of the invention.