AU2018102254A4

AU2018102254A4 - Emissions reducing feed supplement

Info

Publication number: AU2018102254A4
Application number: AU2018102254A
Authority: AU
Inventors: Charles Robert Olsson
Original assignee: Agcotech Ip Pty Ltd
Current assignee: Agcotech Ip Pty Ltd
Priority date: 2017-09-22
Filing date: 2018-09-12
Publication date: 2024-02-22
Anticipated expiration: 2026-09-12
Also published as: AU2018229465A1; WO2019056051A1

Abstract

A feed supplement for ruminants for reducing gas emissions and/or increasing the efficiency of feed utilization by ruminants. The feed supplement, preferably in the form of a feed or lick block, contains a rumen modifier, such as an ionophore, an antibacterial agent or bacteriocidal agent, preferably lasalocid or monensin.

Description

EMISSIONS REDUCING FEED SUPPLEMENT RELATED APPLICATION

[0001] This application claims priority of Australian Patent Application No. 2017903860, filed 22 September 2017 and PCT/AU2018/050958, filed 5 September 2018, the entire contents of which are incorporated herein by way of cross-reference.

TECHNICAL FIELD

[0002] This invention generally relates to a feed supplement for ruminants for reducing gas emissions and/or increasing the efficiency of feed utilization by ruminants. In particular, the invention concerns a feed supplement containing a rumen modifier, such as an ionophore, an antibacterial agent or bacteriocidal agent, preferably lasalocid or monensin.

BACKGROUND ART

[0003] Variable climate usually leads to ruminants changing their foraging/feeding habits throughout the seasons. The nature of the ingested forage/feed will typically affect the efficiency of the feed utilised by the animals. The nature of the ingested forage/feed will also dictate the intensity of greenhouse gas emissions (GHGE) produced by the animals. For example, a low-quality feed/forage diet (e.g. grass or leaves) will typically lead to poor feed utilisation as well as more intense production of GHGE.

[0004] There is, of course, a desire to reduce the intensity of GHGE and to increase the efficiency of feed utilised by ruminant livestock so that livestock production can become more profitable.

SUMMARY OF INVENTION

[0005] It would be advantageous to provide a feed supplement that has the potential to increase livestock production by way of more efficient feed utilisation by the animal and/or decrease the intensity of GHGE.

[0006] In one aspect, the present inventor has now developed a feed supplement that can be used to reduce gas emissions from ruminants and/or increase the efficiency of feed utilization by ruminants.

[0007] According to a first aspect of the present invention, there is provided a feed supplement for a ruminant comprising a rumen modifier capable of reducing gas emissions from the ruminant and/or increasing the efficiency of feed utilization by the ruminant.

[0008] According to a second aspect of the present invention, there is provided a method of reducing gas emissions from a ruminant and/or increasing the efficiency of feed utilization by the ruminant, said method comprising the step of feeding the ruminant a feed supplement according to the 1" aspect of the invention.

[0009] According to a third aspect of the present invention, there is provided a method of manufacturing a feed supplement of the 1" aspect of the invention, said method comprising the step of:

[0010] combining ingredients, including at least one type of rumen modifier, to form a feed supplement.

[0011] The supplement can be of any suitable form such as a liquid, semi-solid or solid e.g. solution, suspension, gelatinous, powder, granule, feed block or lick block. In a preferred embodiment the feed supplement is in the form of a block (feed block or lick block).

[0012] According to a preferred form of the present invention, there is provided a method of manufacturing a feed supplement, said method comprising the steps of:

[0013] combining ingredients, including at least one type of rumen modifier, to form a block mixture;

[0014] pouring the block mixture into a mould; and

[0015] allowing the block mixture to set to form a feed block comprising the at least one type of rumen modifier, preferably substantially uniformly dispersed throughout the block.

[0016] The feed supplement's ingredient content, size and shape can be tailored for the particular ruminant type for which it is provided, or even for the geographic location of the ruminant. For example, grain versus grass fed ruminants many require different ingredient contents, such as different mineral contents. The feed supplement can also be tailored for the palate of the ruminant (e.g. molasses and salt content).

[0017] In addition to containing at least one type of rumen modifier, the feed supplement can for example comprise one or more of the following types of ingredients: a nitrogen source; a protein source; a carbohydrate source; minerals; vitamins; a solidifying, binding or gelling agent; a pH adjuster; a filler; a flavouring agent (to increase palatability of the block); a biological active; and general types of excipients.

[0018] Again, preferably the feed supplement is in the form of a block.

[0019] The types of gases that are typically reduced by the rumen modifier are typically referred to as greenhouse gases and include methane and carbon dioxide. The percentage of gas production will typically be reduced by about 90, 89, 88, 87, 86, 85, 84, 83, 82, 81, 80, 79, 78, 76,75, 74,73,72, 71,70, 69, 68, 67, 66, 65, 64, 63, 62, 61, 60,59, 58, 57,56, 55,54, 53,52, 51,50, 49,48,47, 46,45, 84, 43,42, 41,40, 39, 38, 37, 36, 35, 34, 33, 32, 31, 30,29,28,27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4 or 3%. Preferably the percentage of gas production will typically be reduced between about 60% and 80%, and more preferably about 70% and 80% provided the ruminant is consuming the feed supplement.

[0020] The amount of methane produced per unit of feed dry matter (mL CH 4 / gram of feed dry matter) is preferably reduced by about 40% to 70% provided the ruminant is consuming the feed supplement.

[0021] "Increasing the efficiency of feed utilization by ruminants" as used herein preferably means that ingested feed/forage is more efficiently utilised by the ruminant (for increased body weight gain) by about 80, 79, 78, 76, 75, 74, 73, 72, 71, 70, 69, 68, 67, 66, 65, 64, 63, 62, 61, 60, 59,58,57, 56,55, 54,53,52, 51, 50,49, 48,47, 46, 45, 84, 43,42, 41,40, 39,38, 37,36,35, 34,33,32, 31,30,29,28,27,26,25,24,23,22,21,20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4 or 3%. Preferably, for dry feed, the ingested feed is more efficiently utilised by the ruminant by about a factor of 2.

[0022] Any suitable type of rumen modifier can be used, provided that it can reduce gas emissions from the ruminant and/or increase the efficiency of feed/forage utilization by the ruminant. In some embodiments the rumen modifier is a compound/substance that alters rumen fermentation patterns, to increase feed efficiency and body weight gain. In some embodiments the rumen modifier can inhibit the growth of or kill methanogenic bacteria. In some embodiments the rumen modifier is a bacteriocidal agent. In some embodiments the rumen modifier is an antibacterial agent. In some embodiments, the rumen modifier is an antibiotic. In some embodiments the rumen modifier is a polyether antibiotic. In some embodiments the rumen modifier is an ionophore. In some embodiments the rumen modifier is a divalent polyether ionophore antibiotic. In some embodiments the rumen modifier is monensin, lasalocid, laidlomycin propionate or bambermycin. In preferred embodiments the rumen modifier is lasalocid or monensin. Lasalocid sodium is an antibacterial agent which is produced by strains of Streptomyces lasaliensis and is in the feed additive called BovatecTM. Monensin is a polyether antibiotic isolated from Streptomyces cinnamonensis. In some embodiments the rumen modifier is a yeast capable of killing methanogenic bacteria. In some embodiments the rumen modifier is at least one bacterial strain capable of outcompeting methanogenic bacteria.

[0023] Any suitable type or types and quantity or quantities of rumen modifier can be used. For example, the rumen modifier content can be about 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, 0.15%, 0.2%, 0.25%, 0.3%, 0.35%, 0.4%, 0.45%, 0.5%, 0. 5 5 %, 0.6%, 0.65%, 0.7%, 0.75%, 0.8%, 0.85%, 0.9%, 0.95%, 1%, 1. 5 %, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5. 5 %, 6%, 6.5%, 7%, 7 .5 %, 8%, 8.5%, 9%, 9.5% or 10% weight/weight.

[0024] In some embodiments, the rumen modifier could comprise between about 0.5 kg per tonne (metric ton) up to about 20 kg per tonne of total feed supplement.

[0025] Solidifying, binding or gelling agents help solidify the block/make the block a coherent mass. Suitable examples include calcium oxide, magnesium oxide, calcium hydroxide, di-ammonium phosphate, cement, bentonite and hydrated lime (quick lime). Any suitable solidifying, binding and/or gelling agent/s quantity can be used. For example, the solidifying, binding and/or gelling agent/s content can be about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,20,21,22,23,24,25,26,27,28,29, 30, 31,32,33, 34,35, 36, 37, 38, 39 or 40% weight/weight.

[0026] pH adjusters help adjust the final pH of the block. Examples of suitable pH adjusters include organic acids such as citric, tartaric, boric and phosphoric acid. Any suitable pH adjuster quantity can be used. For example, the pH adjuster content can be about 1, 2, 3, 4, , 6, 7, 8, 9 or 10% weight/weight.

[0027] Fillers help bulk up the block, to get it to the correct volume. The filler can be digestible or not. Examples of suitable fillers include bran (digestible) and earth (not digestible). Any suitable filler/s quantity can be used. For example, the filler/s content can be about 1,2,3,4,5,6,7, 8,9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,20,21,22,23,24,25,26,27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39 or 40% weight/weight.

[0028] Any suitable source or sources of nitrogen can be used. The nitrogen can derive from a source of protein or not. In an example, the source of nitrogen is urea (non-protein source). Any suitable quantity of nitrogen or nitrogen source can be used. For example, the nitrogen or nitrogen source content can be about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20% weight/weight.

[0029] Any suitable source or sources of protein can be used. Suitable sources of protein include cottonseed meal, fish meal, soybean meal and oilseed meal. Any suitable quantity of protein or protein source can be used. For example, the protein or protein source content can be about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20% weight/weight.

[0030] Any suitable source or sources of carbohydrate can be used. Suitable sources of carbohydrate include molasses. Any suitable quantity of carbohydrate or carbohydrate source can be used. For example, the carbohydrate or carbohydrate source content can be about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20% weight/weight.

[0031] The block can include any suitable type of mineral or minerals. Examples of suitable minerals include sodium, phosphorus, sulphur, calcium, sodium, iron, copper, manganese, zinc, iodine, selenium and cobalt. Any suitable mineral quantity can be used. For example, the mineral content can be about 0.5, 1.0, 1.5, 2, 2.5, 3, 3.5, 4, 4.5 and 5% weight/weight.

[0032] The block can include any suitable type of vitamin or vitamins. Examples of suitable vitamins include vitamin A, B, C, D and E. Any suitable vitamin quantity can be used. For example, the vitamin content can be about 0.5, 1.0, 1.5, 2, 2.5, 3, 3.5, 4, 4.5 and 5% weight/weight.

[0033] Any suitable type or types of flavouring agent can be used. Any suitable quantity of flavouring agent/s can be used. Examples of flavouring agents include molasses and salt.

[0034] Any suitable type of salt or salts can be used. Suitable types of salt include sea salt and sodium chloride. Any suitable quantity of salt can be used. For example, the salt content can be about 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20% weight/weight.

[0035] Any suitable type or types of biological actives can be used. Suitable types of biological actives include antibiotics, antimicrobials, rumen stimulants (to encourage the growth of particular rumen microbes), methane-reducing agents (e.g. 3-nitrooxypropanol), and digestion enhancers (eg. vegetable oil). Any suitable quantity of biological active/s can be used. For example, the biological active/s content can be about 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5% or 10% weight/weight.

[0036] In the case of feed supplements in the form of feed blocks, suitable general excipients include antioxidants, colourants, emulsifiers, preservatives, solvents, solubilisers, viscosity increasing agents, diluents, carriers and so forth. Any suitable quantity of water can be used. For example, the water content can be about 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20% weight/weight.

[0037] The molasses of the block provides the following: improves palatability (flavouring agent); provides minerals/trace elements such as sulphur; provides carbohydrates/fermentable sugars; and, functions as a binding agent. Molasses also makes the block easier to manufacture. Any suitable source and quantity of molasses can be used. For example, the molasses content canbe about 1,2,3,4,5,6,7, 8,9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,20,21,22,23,24,25, 26,27,28,29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39,40, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59 and 60% weight/weight. In other embodiments, molasses can be used to balance the ingredient content to 100%. The molasses can be produced from sugarcane, for example.

[0038] Preferably the block has a toffee-like consistency, able to withstanding wet weather as well as temperatures ranging from about -20°C to 50°C.

[0039] Preferably the rumen modifier is substantially uniformly dispersed throughout the block.

[0040] The feed supplement can be fed to any suitable type of ruminant. Suitable ruminants include sheep, cattle, buffalo and goats.

[0041] Preferably, the method comprises the ruminant self-medicating. That is, the ruminant consumes as much of the feed supplement as it desires, as often as it desires. Generally, speaking, the lower the quality feed/forage diet (eg. grass or leaves), the more feed supplement the ruminant will consume to increase digestability/uptake of the feed and reduce the volume of gas expelled from the ruminant. Generally, speaking, for a high quality feed/forage diet (eg. oats), the ruminant should consume less feed supplement.

[0042] Any suitable ratio of feed supplement to feed/forage for ruminants can be used and may depend on whether it is a low quality feed/forage diet (eg. grass or leaves) or high quality feed/forage diet (eg. oats). Examples of suitable feed supplement:feed ratios include 1:10, 1:50, 1:60, 1:70, 1:80. 1:90, 1:100, 1:150, 1:200, 1:250, 1:300, 1:350, 1:400, 1:450, 1:500, 1:550, 1:600, 1:650, 1:700, 1:750, 1:800, 1:850, 1:900, 1:950 and 1:1000, but preferably from about 1:100 to 1:200.

[0043] If a feed block, preferably ruminants consume approximately 50 g to 500 g of block per day. For example, goats and sheep can consume approximately 10 g to 100 g of block per day, and buffalo and cattle can consume approximately 100 g to 400 g of block per day depending on the forage/feed quality.

[0044] The feed supplement can be fed to the ruminant for any required period of time months or years, for example.

[0045] If in the form of a feed block, the block can be manufactured using a hot process (requiring heating of one or more ingredients) or cold process. Preferably, the block is manufactured using a cold process. More preferably, the block is manufactured using a cold moulding process.

[0046] A body of the block can be of any suitable size and shape. The block body can comprise a top surface, a bottom surface and at least one side surface. Potential shapes for the block body include a rectangular, hexagonal or octagonal prism or cylinder/disc, for example.

[0047] The block body can be of any suitable weight but preferably has a weight of between about 5 and 1000 kg, and more preferably about 5, 10, 15, 20, 30, 40, 50, 60, 70, 80, , 100, 150,200, 250, 300, 350, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950 and 1000 kg.

[0048] Particularly preferred embodiments of feed block are described below.

[0049] Preferably, the feed block comprises at least about 50% weight/weight molasses.

[0050] Preferably, the feed block comprises about 5 to 10% weight/weight salt.

[0051] Preferably, the feed block comprises at least one type of phosphate. Any suitable type or types and quantity of phosphate can be used. For example, the phosphate content can be about 5-10% weight/weight. A suitable phosphate is di-calcium phosphate.

[0052] Preferably, the feed block comprises at least one type of hydrated lime. Any suitable type and quantity of hydrated lime can be used. For example, the hydrated lime content can be about 0-5% weight/weight.

[0053] Preferably, the feed block comprises magnesium oxide. Any suitable quantity of magnesium oxide can be used. For example, the magnesium oxide content can be about 10 % weight/weight.

[0054] Preferably, the feed block comprises minerals such as copper, cobalt, zinc and selenium. Any suitable mineral quantity can be used. For example, the mineral content can be about 1-2% weight/weight.

[0055] Preferably, the feed block comprises up to about 10% weight/weight water.

[0056] Preferably, the feed block comprises about 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, 0.15%, 0.2%, 0.25%, 0.3%, 0.35%, 0.4%, 0.45%, 0.5%, 0.55%, 0. 6 %, 0. 6 5%, 0. 7 %, 0. 7 5%, 0. 8 %, 0. 8 5%, 0. 9 %, 0. 9 5%, 1%, 1.5%, 2%, 2.5%, 3%

, 3 .5%, 4%, 4 .5%, 5%, 5.5%, 6%, 6 .5%, 7%, 7 .5%, 8%, 8 .5%, 9%, 9 .5% or 10% weight/weight of each type of rumen modifier. (Usually 0.5 kg to 20 kg for each type of rumen modifier per metric ton of block.) A preferred type of rumen modifier is the antibiotic ionophore lasalocid or monensin.

[0057] Optionally, the feed block comprises about 5-10% weight/weight of phosphoric acid.

[0058] Optionally, the feed block comprises at least one type of protein source/meal. Any suitable type or types and quantity or quantities of meal can be used. For example, the meal content can be up to about 2% weight/weight. Suitable meal is, for example, cottonseed meal, fish meal, soybean meal and oilseed meal.

[0059] A particularly preferred feed block comprises the following ingredients (all weight/weight):

[0060] 50% (or to balance) molasses

[0061] 5 to 10% salt

[0062] 5 to 10% phosphate (e.g. di-calcium phosphate)

[0063] Up to 5% hydrated lime

[0064] 10 to 20% magnesium oxide

[0065] 1 to 2% minerals (including copper, cobalt, zinc, selenium)

[0066] 10% water

[0067] Each type of rumen modifier (e.g. lasalocid or monensin) - Quantity to suit so as to provide adequate gas emission reduction and/or increased feed utilisation (E.g. approx. 0.01% %, more preferably about 0.5% to 2%. Usually 0.5 kg to 20 kg for each type of rumen modifier per metric ton of block.)

[0068] Any of the features described herein can be combined in any combination with any one or more of the other features described herein within the scope of the invention.

[0069] The reference to any prior art in this specification is not, and should not be taken as an acknowledgement or any form of suggestion that the prior art forms part of the common general knowledge.

[0070] Preferred features, embodiments and variations of the invention may be discerned from the following Detailed Description which provides sufficient information for those skilled in the art to perform the invention. The Detailed Description is not to be regarded as limiting the scope of the preceding Summary of the Invention in any way.

DETAILED DESCRIPTION

[0071] FIGURES

[0072] Figure 1. Organic matter digestibility, ammonia nitrogen, and gas production of blank (only rumen fluid), only supplement at an amount equivalent to 2.5% of feed (no feed added), Rhodes Grass (RG) only, RG plus 2.5% of supplement, and RG plus 5% of supplement.

[0073] Figure 2. Organic matter digestibility, ammonia nitrogen, and gas production of blank (only rumen fluid), only supplement with an amount equivalent to 10% of feed, oats only, oats plus 5% of supplement, and oats plus 10% of supplement.

[0074] Figure 3. Organic matter digestibility, ammonia nitrogen, and gas production of blank (only rumen fluid), only 1 gr. of supplement (no feed added; supplement at an amount equivalent to a consumption of 300 g/d for a 400-kg steer), mulga leaves only, and mulga plus supplement.

[0075] Example 1 - Manufacture of a feed supplement in the form of a feed block

[0076] This example describes the manufacture of a feed block supplement containing a rumen modifier, manufactured using a cold moulding process.

[0077] Molasses and hydrated lime were mixed together in water using a high-speed mixer. Other ingredients, including salt, di-calcium phosphate, magnesium oxide, minerals and rumen modifier were added in turn, and the mixture was poured into a mould and allowed to set for about 48 hours.

[0078] The block supplement consisted of the following ingredients (all weight/weight):

[0079] 50% molasses

[0080] 5 to 10% salt

[0081] 5 to 10% di-calcium phosphate

[0082] Up to 5% hydrated lime

[0083] 10 to 20% magnesium oxide

[0084] 1 to 2% minerals (including copper, cobalt, zinc, selenium)

[0085] 10% water

[0086] Lasalocid sodium and/or monensin. Quantity to suit so as to provide adequate gas emission reduction and/or increased feed utilisation (e.g. approx. 0.01% - 10%, more preferably about 0.5% to 2%). Will depend on feed/forage type.

[0087] When set, the block had a toffee-like consistency.

[0088] The block had a weight of 20 kg. The rumen modifier was substantially uniformly dispersed throughout the supplement block. The consistency of the block was like toffee.

[0089] Some of the advantages of the supplement block as described in this Example are stated below:

[0090] 1. It is rain-resistant in that it will not readily dissolve in rain.

[0091] 2. It is stable within the following temperature range: -20 to 50°C. Therefore, the block is suitable for use in Australia as well as countries having similar climates/environmental conditions such as South-East Asia, including New Zealand, Indonesia, Laos, Vietnam, Malaysia, Cambodia, China, India and Myanmar.

[0092] 3. It is highly palatable, particularly to ruminants such as sheep and cattle.

[0093] 4. The rumen modifier (and other biological actives) can be substantially uniformly dispersed throughout the block.

[0094] 5. The block releases the rumen modifier/s in a uniform and controlled manner.

[0095] 6. The block enables controlled consumption - low daily dose of rumen modifier, thereby minimising the risk of overdosing.

[0096] 7. The rate of cold production of the block is high, being about 50 tonnes of block per day.

[0097] 8. The block need not require urea as an ingredient.

[0098] 9. Animals can self regulate consumption to gas emission and at the same time intake essential nutrients to increase productivity (body mass gain).

[0099] 10. The feed block saves farmers having to muster and handle animals, as well as delivering rumen modifiers.

[00100] Example 2 - In vitro fermentation trials using the feed supplement block of Example 1

[00101] Summary

[00102] Three in vitro fermentation trials using a 'year-round' feed block supplement ('supplement' of Example 1) for cattle were carried out. One fermentation trial used an amount of supplement to achieve similar concentration of the supplement to what is achieved in the rumen of animals consuming low quality mulga forage, i.e. 8 gr of supplement per litre of rumen fluid. The most relevant results are for the amount of gas produced per gram of digested feed organic matter (OMD). The amount of gas produced was increased by 73% when the supplement was not used in low quality mulga forage (285 vs. 495±7 mL / g OMD for mulga with and without supplement; P < 0.001). Another trial used an amount of supplement similar to what is achieved in the diet of animals consuming high quality oat forage, i.e. 10 g of supplement per 100 g of oats. Gas production increased by 5% when the supplement was not used in high quality oat forage (249 vs. 262 ±4.9 mL / g OMD for oats with and without supplement; P < 0.001). This reduction in gas production may be due to a change in the fermentation pattern towards less methane and C02 production, and more propionate. This mechanism should also increase the efficiency of feed utilization by the animal to produce and reduce the intensity of greenhouse gas emissions.

[00103] Results of in vitro fermentation trials

[00104] Experimental details

[00105] Three in vitro fermentation trials were conducted where 25 mL of rumen fluid from a fistulated cow were mixed with 100 mL of artificial saliva and 1 gram of feed. Treatment diets consisted of supplement added at different quantities. Incubations took place for 72 hours and the following was measured:

[00106] - Feed digestibility (organic matter (OMD) and dry matter digestibility (DMD)).

[00107] - Total gas produced which is an indicator of digestibility and the amount of gas produced for each gram of digested feed.

[00108] - Ammonia nitrogen (NH3 -N) which is an indicator of protein availability and degradation.

[00109] - Methane and C02 production under analysis at present (mitigation potential of greenhouse emissions from supplements).

[00110] Several other measures were also taken and analyzed but not presented herein for simplicity (e.g. final pH and volatile fatty acids profile).

[00111] It is important to note that the in vitro technique is not a good technique to assess the effects of mineral supplements (e.g. phosphorus) on digestion and nutrition because the artificial saliva used has a high mineral content. However, it is a good technique to assess the effect of supplement diet digestibility and greenhouse emissions.

[00112] Supplement was used at the following rates:

[00113] Trial 1: 2.5 or 5 gr of supplement per 100 gr of low quality dry Rhodes grass. This was calculated assuming that a 400 kg steer would consume 150 or 300 gr/d of supplement and 6 kg/ d of forage.

[00114] Trial 2: 5 or 10 gr of supplement per 100 gr of high quality oats forage. This amount was calculated assuming that a 400 kg steer would consume 400 or 800 gr/d of supplement with a feed intake of 8 kg DM/d of oats.

[00115] Trial 3: 100 gr of supplement per 100 gr of very low quality mulga leaves. This amount was calculated to simulate the final concentration of supplement in the rumen of a 400 kg steer with a rumen volume of 40 L consuming 300 g/d of supplement.

[00116] The above 3 trials were expected to ascertain which is more important:

[00117] - The concentration of the supplement in relation to the total rumen volume.

[00118] - The concentration of the supplement in relation to the amount of feed consumed per day.

[00119] Results

[00120] Overall results showed that the feed supplement has a potent effect to reduce the amount of gas produced per gram of digested feed (OM) with a positive (low quality diets) or null (high quality diet) effect on digestibility depending on the diet. Indicators of protein degradation and availability did not seem to give clear results.

[00121] The addition of 5 gr of supplement per 100 grams of Rhodes grass (RG) slightly increased feed OM digestibility (OMD) by 5%, ammonia-nitrogen by 18% and total gas production by 6%. However, the amount of gas produced per gram of OM digested was reduced by 2% (Figure 1). Therefore, the supplement seems to have a positive effect on feed digestibility, nitrogen availability and the amount of gas produced per unit of digested feed.

[00122] In contrast to trial 1, addition of the supplement in trial 2 did not seem to have a significant effect on OMD when incubated with high quality forage oats (Figure 2). However, similar results to trial 1 were found with an increase in ammonia nitrogen, total gas produced and a 5% reduction of the amount of gas produced per unit of digested feed (mL of gas / g of digested organic matter).

[00123] Trial 3 assessed the effect of the supplement of mulga leaves which is a tree of the Acacia family that occupy large areas of arid and semiarid Australia dedicated to animal production. This tree has very low digestibility because of its high fiber and low protein, and high concentration of tannins which reduce protein degradation, digestibility and methane emissions. The amount of supplement was increased to simulate the concentration that the supplement would reach in the rumen liquid of a live animal.

[00124] There were very large and significant effects of the supplement on OMD and gas production whereas ammonia nitrogen was not affected (Figure 3). Of particular importance is the 42% reduction in the amount of gas produced per unit of digested OM of the mulga leaves incubated with the supplement compared to only mulga leaves without supplement. Furthermore, there seems to be a synergistic effect between mulga leaves and supplement because gas production per gram of digested OM was even lower than the supplement only.

[00125] Example 3 - Modelling the changes in greenhouse emissions as a result of feed supplementation

[00126] Summary

[00127] Feed supplementation has the potential to increase beef production and decrease the intensity of greenhouse gas emissions (GHGE). The Example takes a prediction modelling approach to estimate potential productivity gains and reduction of GHGE from a breeding herd in northern Australia. These predictions were done for the following 5 scenarios: scenario 1) unsupplemented herd with 3,000 breeding cows and 55% weaning rate; scenario 2) same herd with supplementation resulting in 65% weaning rate, 15% higher weaning weight (from 165 to 190 kg/hd) and a reduction in mortality rates (by 2%); scenario 3) same as scenario 2 with joining of heifers at younger age as a result of achieving joining weight earlier; scenario 4) same as scenario 2 plus the effect of feed supplement to reduce methane emissions by 10% without impacting production or feed intake; and scenario 5) same as scenario 3 plus the effect of feed supplement to reduce methane emissions by 10%.

[00128] Results from predictions suggest that feed supplementation in scenario 2 could increase production of LW by 55% and reduce the intensity of GHGE (kg CO2e/kg live weight) by 24% equating to and abatement of 3,533 tonnes CO2e/yr compared to the same unsupplemented herd. Predictions from scenario 3 indicated that production of LW could be increased by 83% and the intensity of GHGE could be reduced by 34% equating to an abatement of 5,891 tonnes CO2e/yr compared to the unsupplemented herd. Scenario 4 and 5 produced the same amount of LW as scenario 2 and 3 however the reduction of intensity of GHGE was of 31 and 42% equating to an abatement of 4,568 and 6,954 tonnes CO2e/yr, respectively. Abatement of GHGE could generate an extra income above that of the unsupplemented herd of $42,435, $70,694, $54,812 and $83,449 for scenario 2, 3, 4 and 5, respectively (CO2 price = 12 $/tonne). Furthermore, the increase in live weight sales could generate an income above the unsupplemented herd of $589,725 for scenario 2 and 4, and of $820,227 for scenarios 3 and 5. Feed supplementation could have a large positive impact on greenhouse emissions, beef production and profitability of northern Australian properties if these levels of abatement and productivity are achievable on farm.

[00129] Predicting changes in greenhouse emissions and beef production using a modelling approach

[00130] Low fertility (calves weaned), high mortality rates and low growth rates threaten the viability of northern Australian beef production because it has a large impact on beef productivity, greenhouse gas emissions (GHGE) and profitability. The causes for these are various but one of the most important is the variable climate leading to changing feed characteristics throughout the seasons. During the long dry seasons, forage digestibility and crude protein can reach alarming levels in the rangelands (40% DMD and 4% CP). Feed supplementation could alleviate the negative impacts this has on animal growth, reproduction and mortality, and GHGE as well. As a result of the importance of GHGE from livestock, several initiatives have been taken to promote strategies that reduce the environmental footprint of livestock production such as the newly approved methodology within the Emissions Reduction Fund called Beef Herd Management Methodology. This methodology awards Australian Carbon Credit Units (1 ACCU = 1 ton CO2e) that are avoided from livestock, which can then be purchased or auctioned.

[00131] The aim of the present study was to estimate potential productivity gains and reduction of greenhouse emissions by using feed supplementation across all animal categories throughout the year in a beef breeding herd in northern Australia.

[00132] Experimental details

[00133] We used a modelling approach similar to that used by the Australian Government in the Beef Herd Management Methodology determination to estimate the abatement of greenhouse emissions as a result of improving productivity and efficiency (http://www.environment.gov.au/climate-change/emissions-reduction-fund/methods/beef cattle-herd-management). This is the approved methodology used by the Emissions Reduction Fund to estimate abatement from beef herds that participate in the scheme. It is also similar to the methodology used by the Australian Government in the National Inventory Report 2014 to the Intergovernmental Panel for Climate Change (http://www.environment.gov.au/climate change/greenhouse-gas-measurement/publications/national-inventory-report-2014-revised).

[00134] The case study was based on a hypothetical self-replacing beef breeding herd with 3,000 breeding cows selling all surplus calves at weaning. The assumptions in terms of animal numbers, herd fertility, mortality, growth rate and live weight sales for the 5 scenarios tested are shown in Table 1.

[00135] Table 1. Animal numbers, fertility, mortality, live weights and weight gain for each animal category used as assumptions in scenario 1 (control) and 2 (supplemented) for predicting productivity gains and greenhouse emissions of a breeding herd in northern Australia.

Weight Weight Losses, start, and, Weight Opening# Losses, % Nro Closing# kg/hd kg/hd gain,kg

Nosupplemmntatton

Total Breeders > 3 yrs 3,000 &0 240 2,760 550 550 0

Breeders>4yrs 2,304 &i0 185 2,120 550 550 0 Calvingheifers3-4yrs 696 8,0 55 641 550 550 a Pregnancy rate, % 70 2,100 CaMn g rate, % 65 15.4 1,950 Brandingrate,% 61 7.7 150 1300 Weaning rate,3% 55 K.3 150 1,50 80 165 85 Heifers 2-3 yrs 732 5,0 36 696 380 510 130 H eifers 1-2 yrs 770 5) 38 732 250 380 130 Heifers<Iyrs (27% replacement) 810 50 770 80 250 170 Bulls 120 5.0 6 114 700 700 0 Total animals >1 yr 5,432 11.4 620 5,073 Sales Cullcows 456 550 550 0 Male calves 825 80 165 85 Fernale calves 15 80 165 85

SupphainuntatIon Total Breeders > 3yrs 3,000 5 150 2,850 625 625 0 Beeders>4yrs 2,259 5.0 112 2,147 625 625 0 Calving heifers 3-4 yrs 741 50 38 704 625 625 a Pregnancy rate, % s0 2,400 Calvng rate, % 75 133 2,250 Branding rate, % 70 6.7 150 2,100 Weaning rate, % 65 7.1 150 1,950 Heifers 2-3 yrs 763 3.0 22 741 450 600 150 Hefers 1-2 yrs 786 3.D 23 763 300 450 150 Heifers <1 yrs (27% replacement) 810 310 785 100 300 200 Bulls 120 3.0 3 117 800 800 0 Total animIals 1 yr 5,479 9.1 498 5,258 Sales Cull Cows 591 625 625 0 Male calves 975 90 190 100 Female calves 165 90 190 100

[00136] The 5 scenarios that were simulated to estimate outcomes in terms of GGHE and productivity are:

[00137] [) A business-as-usual (control) beef breeding herd with no supplementation (55% weaning rate).

[00138] 2) The same herd assumed to be supplemented throughout the year across all animal categories which increased female fertility (65% weaning rate), growth rate and live weight.

Joining age of heifers was same as in scenario 1 (2 years) with calving at 3 years-old.

[00139] 3) The same as scenario 2 but with heifers joined at approximately 15 months and calving at 2 years of age as a result of heavier weight reaching joining weight and maturity at younger age.

[00140] 4) Same as scenario 2 but assuming a 10% reduction in the amount of methane produced per kg of feed dry matter consumed in addition to increased productivity. Our in vitro fermentation trials in Example 2 with feed supplements indicated that the amount of methane produced per unit of feed dry matter (mL CH 4 / gram of feed dry matter) could be reduced by 8 to 25%. A conservative approach was assumed at 10% reduction when using the supplement.

[00141] 5) Same as scenario 3 but assuming a 10% reduction in the amount of methane produced per kg of feed dry matter consumed in addition to increased productivity.

[00142] Briefly, scenario 1 is a typical beef breeding herd with 3,000 breeding cows, 5% mortality for younger stock and 8% for older stock. Weaners are sold at 6 months with 165 kg/hd live weight (LW) and 15% mortality of calves between birth and weaning. Almost all the female calves are kept for replacements (27% of the breeding cows) and joining occurs at 2 years of age for calving at 3 years (Table 1). Scenario 2 is very similar to the controls and assumes higher fertility (65% weaning rate), lower mortality rate (3, 5 and 13% for young stock, adult and calves), and higher growth rate and weights of all animals as a result of feed supplementation. However, the total number of animals on the farm is very similar to scenario 1 (Table 1). Finally, scenario 3 is similar to scenario 2 but it assumes an earlier joining at approximately 15 months of age as a result of faster growth rate (Table 2). These heifers calve at 2 years of age and were assumed to have lower fertility compared to the main breeding herd (53% weaning rate).

[00143] Table 2. Animal numbers, fertility, mortality, live weights and weight gain for each animal category used as assumptions in scenario 3 for predicting productivity gains and greenhouse emissions of a breeding herd in northern Australia.

Weight Weight Losses, start, end, Weight Opening# Losses,% Nro Closing# kg/lid kg/hd gain,kg

Supplmentation and earlier cahvng Total Breeders > 3yrs 3,000 5.0 150 2,850 625 625 0 Breeders > 4 yrs 2,259 5.0 112 2,147 625 625 0 Calving heifers 3-4 yrs 741 5.0 38 704 Pregnancy rate,% 80 2,934 Calving rate, % 75 13.8 2,731 Branding rate, % 70 **63 173 2,558 Weaning rate, % 65 **tO 203 2,354 Heifers2-3yrs 763 3.0 22 741 450 600 150 Pregnancy rate: 70% Claving rate: 63% Branding rate 60% Weaning rate: 53% Helfers 1 2 yrs 786 3.0 23 763 300 450 150 Hefers<1yrs(27%replacement) 810 3,0 786 100 300 200 Bulls 120 3.0 3 117 SW Sao 0 Total animals > 1 yr 5,479 10.5 574 5,304 Sales CUll cows 591 625 625 0 Male calves 1,177 90 190 100 Female carves 367 90 190 100

Yelow ca mortality from birth to weaning. Blue: calf mortality from birth to branding. ***Purple calf mortality from branding to weaning.

[00144] Scenario 2 and 3 are presently recognized by the ERF Herd Management Methodology to claim carbon credits as a result of increased productivity and / or reduced time on earth of the animals. However, there are no methodologies approved for beef cattle which allow claiming carbon credits as a result of rumen modification other than nitrates (e.g. monensin is not an accepted methodology), Therefore, the additive effect of improving productivity and reducing the amount of methane produced daily was simulated in scenarios 4 and 5 where a 10% reduction in methane emissions per kg of feed dry matter consumed was assumed based on our in vitro fermentation trials.

[00145] The number of animals and the weight of each animal category were calculated for each scenario according to the assumed fertility and mortality rates. The number of animals sold (surplus weaners and cull cows) was also estimated according to these assumptions and then the weight at sale allowed the calculation of total sales of live weight per year.

[00146] Feed intake is calculated from live weight and growth rate, which is then multiplied by a factor to estimate daily methane emissions. Digestibility of feed dry matter (DMD) and crude protein are also used to calculate methane emissions and N excretion as nitrous oxide which is another potent greenhouse gas from manure particularly. These values of DMD and

CP are assumed as in the methodology for each season.

[00147] Methane and nitrous oxide are then converted to CO2e and total emissions from the herd are estimated. Beef production is calculated as the difference between live weight at the end and the start of the year for each animal class. Live weight sold per year is calculated as the number of animals sold by the average weight per animal for each animal class.

[00148] The intensity of GHGE is then calculated as total emissions from the herd (ton CO2e) divided by live weight produced. The potential economic income generated by each scenario is calculated assuming a price of 3 $/kg LW and 12 $/ton CO2e being both conservative values.

[00149] Results

[00150] Scenario 2 and 3 resulted in more cull cows being sold compared to the control herd as a result of lower mortality and higher fertility. All animals are heavier in all scenarios compared to the control herd because all animals maintained better body condition from feed supplementation. Scenario 3 assumed to sell the same number of cull cows but greater number of calves compared to scenario 2, as a result of heifers calving at a younger age. However, the weight of all animals was assumed the same for both scenario 2 and 3 albeit the number of animals in the main herd were similar across all 3 scenarios. The higher fertility and lower mortality of calves in supplemented herds compared to control herd resulted in 18.2% more weaned calves in scenario 2 compared to the control herd. However, this translated into 36.2% more calves sold with 15% heavier weight in scenario 2 compared to the control herd because a higher number of female calves have to be kept as replacement due to lower fertility (Table 1). Similarly, 29.6% more cull cows with 13.6% heavier weight were sold in the supplemented herd of both scenarios compared to the control herd. The additive effect of lower mortality, higher fertility and earlier joining of heifers in scenario 3 resulted in 42.7% more calves weaned compared to the control unsupplemented herd whereas the number of calves sold was 83.9% higher in Scenario 3 (Table 2) compared to the unsupplemented herd (Table 1).

[00151] The total live weight produced by the herd per annum was 55 and 84% higher in scenario 2 and 3 with feed supplementation, respectively, compared to the control unsupplemented herd (Table 3).

[00152] Table 3. Annual live weight produced and sold from a beef breeding herd with no feed supplementation, with feed supplementation, and with feed supplementation plus early joining in northern Australia.

Annual Annual Herd Herd Changein Liveweight Liveweight Incomefrom income from Gain (t lyr) Sold (tlyr) beef,S/yr control, Slyr Not supplemented (Scenario 1) 481 389 1,168,200 Supplemented (scenario 2) 746 586 1,757,926 589,725 Supplemented and early joining 883 663 1,988,427 820,227

[00153] However, part of this live weight produced stays on farm as replacement heifers and less is sold. The total live weight sold per year as cull cows and weaners was predicted to be 50 and 70% higher for scenario 2 and 3, respectively, compared to the control unsupplemented herd. This could generate extra income of $590,000 and $820,227 per year for scenario 2 and 3, respectively, compared to the control herd (Table 3). Beef production for scenarios 4 and 5 were the same as for scenarios 2 and 3 and therefore are not shown.

[00154] Total greenhouse emissions (GHGE) in tonnes per year were higher in the supplemented herds 2 and 3 compared to the control unsupplemented herds (Table 4) because more feed is consumed by heavier animals with faster growth rates.

[00155] Table 4. Abatement of greenhouse emissions (GHGE) from a beef breeding herd with no feed supplementation, with feed supplementation, with feed supplementation plus early joining, in northern Australia.

Enteric Nitrous Total Emissions intensity Emissions Oxide emissions of herd liveweight Total baseline Net (t CO2e/ Emissions t(t CO2e I gain (t CO2e it emissions(t Abatement Incomefrom yr) CO2e I yr) year) live weight) CO2eyr {t CO2elyr) GHGE, 5/yr Not supplemented (Scenario 1) 9,125 704 9,830 20.4 9,830

Supplemented (Scenario 2) 10,315 783 11,097 14.9 14, 34 3,536 42,435 Supplemented and early joining (Scenario 3) 10,630 808 11,438 12-9 17,329 5,891 70,694 Supplemented plus reduction from supplement (scenario 4) 9,283 783 10,066 135 14, 34 4,568 54,812 Supplemented, early joining and reduction from supplement (scenario 5) 9,567 808 10,375 11.7 17,329 6,954 83,449

[00156] However, total GHGE per year is less relevant than the intensity of GHGE, i.e. amount of GHGE per unit of liveweight produced. The intensity of GHGE is what the ERF methodologies recognise and reward rather than total GHGE. The intensities of GHGE were 27% and 36% lower in supplemented scenarios 2 and 3 compared to the control unsupplemented herd (Table 4). These GHGE intensity values are then used to estimate total baseline emissions for scenario 2 and 3, which is the total amount of GHG that would have been emitted to produce the liveweight obtained in these alternative scenarios would these have shown the emissions intensity of the unsupplemented herd (20.4 kg CO2e / kg of LW). Thus, baseline emissions show a reduction in GHGE of 24 and 34% for scenarios 2 and 3 compared to the control herd (Table 4) which result in a net abatement of 3,536 and 5,891 tonnes CO2e /yr, respectively. At 12 $/tonne of CO2e, such abatement could produce an income of $42,435 and $70,694 per annum (Table 4).

[00157] Further abatement of GGHE in scenarios 4 and 5 are estimated compared to scenario 2 and 3 (Table 4) when the estimation of GHGE account for the ability of certain supplements containing rumen modifiers (such as monensin) to reduce the amount of methane produced per gram of feed consumed and digested. These scenarios have reduced the total amount of emissions from enteric fermentation and therefore the emissions intensity per unit of live weight. As a result, emissions intensity is reduced by 34 and 43% in scenarios 4 and 5 compared to the control unsupplemented herd, resulting in a net abatement of 4,568 and 6,954 tonne CO2e / yr (Table 4), respectively. The extra income from abatement generated by scenario 5 is nearly doubled if a reduction of GHGE as a result of using rumen modifiers was recognised and earlier joining possible in practice compared to scenario 2.

[00158] Conclusion

[00159] The use of feed supplementation in beef cattle of northern Australia has positive additive effects on all productivity indicators such as reproduction, mortality, growth rate and sale of live weight. This increase of productivity results in large reduction of greenhouse emissions when expressed as intensity of emissions (kg GHG / kg LW). Furthermore, feed supplements containing rumen modifiers such as monensin can further reduce the amount of greenhouse gasses as these reduce the amount of methane per unit of feed consumed.

[00160] In the present specification and claims (if any), the word 'comprising' and its derivatives including 'comprises' and 'comprise' include each of the stated integers but does not exclude the inclusion of one or more further integers.

[00161] Reference throughout this specification to 'one embodiment' or 'an embodiment' means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearance of the phrases 'in one embodiment' or 'in an embodiment' in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more combinations.

[00162] In compliance with the statute, the invention has been described in language more or less specific to structural or methodical features. It is to be understood that the invention is not limited to specific features shown or described since the means herein described comprises preferred forms of putting the invention into effect. The invention is, therefore, claimed in any of its forms or modifications within the proper scope of the appended claims (if any) appropriately interpreted by those skilled in the art.

Claims

1. A feed supplement for a ruminant comprising a rumen modifier capable of reducing gas emissions from the ruminant and/or increasing the efficiency of feed utilization by the ruminant.

2. The feed supplement of claim 1, wherein the feed supplement is in the form of a liquid, semi solid or solid.

3. The feed supplement of claim 1 or claim 2, further comprising one or more of the following types of ingredients: a nitrogen source; a protein source; a carbohydrate source; minerals; vitamins; a solidifying, binding or gelling agent; a pH adjuster; a filler; a flavouring agent; a biological active; and excipient.

4. The feed supplement of any one of the preceding claims, wherein said feed supplement is capable of reducing gas emissions by between about 60% and 80%.

5. The feed supplement of any one of the preceding claims, wherein said feed supplement is capable of reducing gas emissions by between about 70% and 80%.

6. The feed supplement of claim 4 or claim 5, wherein with regard to reducing gas emissions, the amount of methane produced per unit of feed dry matter (mL CH4 / gram of feed dry matter) is reduced by about 40% to 70%.

7. The feed supplement of any one of the preceding claims, wherein ingested dry feed is more efficiently utilised by the ruminant by about a factor of 2.

8. The feed supplement of any one of the preceding claims, wherein the rumen modifier is capable of altering rumen fermentation patterns, to increase feed efficiency and body weight gain.

9. The feed supplement of any one of the preceding claims, wherein the rumen modifier inhibits the growth of, or kills, methanogenic bacteria.

10. The feed supplement of any one of the preceding claims, wherein the rumen modifier is a bacteriocidal agent, an antibacterial agent, an antibiotic, a polyether antibiotic or an ionophore.

11. The feed supplement of claim 10, wherein the rumen modifier is a polyether ionophore antibiotic.

12. The feed supplement of claim 11, wherein the rumen modifier is monensin.

13. The feed supplement of claim 11, wherein the rumen modifier is lasalocid.

14. The feed supplement of claim 11, wherein the rumen modifier is laidlomycin propionate.

15. The feed supplement of claim 11, wherein the rumen modifier is bambermycin.

16. The feed supplement of any one of the preceding claims, wherein the rumen modifier comprises between about 0.5 kg per metric tonne up to about 20 kg per metric tonne of total feed supplement.

17. The feed supplement of any one of the preceding claims, wherein the rumen modifier is substantially uniformly dispersed throughout the feed supplement.

18. The feed supplement of any one of the preceding claims, wherein the feed supplement is in the form of a feed block or lick block.

19. The feed supplement of claim 18, wherein the feed block or lick block comprises the following ingredients (weight/weight): 50% (or to balance) molasses; 5 to 10% salt; 5 to 10% phosphate (e.g. di-calcium phosphate); up to 5% hydrated lime; 10 to 20% magnesium oxide; 1 to 2% minerals (including copper, cobalt, zinc, selenium); 10% water; and 0.01% - 10% each type of rumen modifier.

20. A method of manufacturing a feed supplement, said method comprising the step of combining ingredients, including at least one type of rumen modifier, to form the feed supplement of any one of claims I to 19.

21. A method of reducing gas emissions from a ruminant and/or increasing the efficiency of feed utilization by the ruminant, said method comprising the step of feeding the ruminant a feed supplement according to any one of claims 1 to 19.

22. The method of claim 21, comprising the step of the ruminant self-medicating.

23. The method of claim 21 or claim 22, wherein the ruminant is fed a feed supplement:feed ratio of about 1:10 to 1:1000.

24. The method of claim 23, wherein the ruminant is fed a feed supplement:feed ratio of about 1:100 to 1:200.

25. The method of any one of claims 21 to 24, wherein if the feed supplement is in the form of a feed block, then the ruminant consumes approximately 10 g to 500 g of feed block per day, preferably a goat or sheep consumes approximately 10 g to 100 g of feed block per day, or a buffalo or bovine animal consumes approximately 100 g to 400 g of block per day.

26. The method of any one of claims 21 to 25, wherein said gas emissions are reduced by between about 60% and 80%.

27. The method of any one of claims 21 to 26, wherein said gas emissions are reduced by between about 70% and 80%.

28. The method of any one of claims 21 to 27, wherein the amount of methane produced per unit of feed dry matter (mL CH 4 / gram of feed dry matter) is reduced by about 40% to 70%.

29. The method of any one of claims 21 to 28, wherein ingested dry feed is more efficiently utilised by the ruminant by about a factor of 2.

30. A method of manufacturing a feed supplement, said method comprising the steps of:

combining ingredients, including at least one type of rumen modifier, to form a block mixture;

pouring the block mixture into a mould; and

allowing the block mixture to set to form a feed block comprising the at least one type of rumen modifier, preferably substantially uniformly dispersed throughout the block.

31. The method of claim 30, wherein the rumen modifier is a bacteriocidal agent, an antibacterial agent, an antibiotic, a polyether antibiotic or an ionophore.

32. The method of claim 30, wherein the rumen modifier is a polyether ionophore antibiotic.

33. The method of claim 30, wherein the rumen modifier is monensin.

34. The method of claim 30, wherein the rumen modifier is lasalocid.