CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Patent Application No. 63/366,348, filed June 14, 2022, which is incorporated by reference herein in its entirety.

TECHNICAL FIELD

[0002] This application relates to methods for feeding swine a feed that includes a nitrate compound for improving feed efficiency.

BACKGROUND

[0003] Feeding calcium nitrate and other ingredients to livestock is one way to mitigate methane production. For example, U.S. Patent No. 8,771,723 titled “Compositions For Reducing Gastro-Intestinal Methanogenesis In Ruminants” issued to Hindrik Bene Perdok et al. discloses one such method. Further, Van Den Bosch et al. (International Patent Application Publication No. WO 2016/090366, published June 9, 2016) describes animal feed compositions containing a nitrate compound and methods for using such a composition in an animal’s gestation phase and/or lactation phase to improve the health of offspring. Ascensao et al. (International Patent Application Publication No. WO 2018/237233) describes methods of improving meat quality (such as meat color and carcass yield (%)) in an animal by feeding an effective amount of nitrate to the animal.

[0004] In humans, dietary nitrate, as presented in beetroot juice, has been shown to reduce blood pressure and the risk of adverse cardiovascular events in healthy individuals after single dose of 500 ml of beetroot juice. It is hypothesized that nitrate might represent a source of vasoprotective nitric oxide (NO) via bioactivation (Webb et al. 2008). A non- enzymatic pathway for the generation of NO has been proposed (nitrate-nitrite-NO pathway) for humans. Dietary inorganic nitrate molecules may be reduced by facultative anaerobic bacteria on the dorsal surface of the tongue to nitrite which can be chemically and enzymatically be further reduced to NO (Lundberg et al. 2009). The endothelial isoform of the NO synthase uses arginine and molecular oxygen as precursors to tonically release NO in the endothelium, which is important for the control of vascular tone, smooth muscle growth, platelet aggregation and inflammation (Umans and Levi, 1995; Bruckdorfer 2005). This induces vasodilation and increased blood flow (Siervo et al. 2011; Keim 1999). SUMMARY

[0005] In one aspect, the present technology provides a method for improving feed efficiency (i.e., feed conversion ratio), the method includes feeding to swine about 70 mg/kg bodyweight (BW) per day or less of a nitrate compound, hydrates thereof, salts thereof, or combinations thereof; wherein the method improves feed conversion measured as feed to gain ratio (feed:gain) of the swine compared to a control swine not fed 70 mg/kg BW per day of the nitrate compound, hydrates thereof, salts thereof, or combinations thereof; and wherein the swine is in one or more of a post-weaning phase, growth phase, or finishing phase.

[0006] In another aspect, the present technology provides a method for feeding swine, the method comprising: feeding swine a swine feed comprising a nitrate compound, hydrates thereof, salts thereof, or combinations thereof; wherein: the swine is fed a daily feed intake comprising an amount of nitrate is in a range of about 0.02% by weight to less than about 0.10% by weight based on total weight of the swine feed; the method improves feed conversion measured as feed to gain ratio of the swine compared to a control swine not fed the nitrate compound, hydrates thereof, salts thereof, or combinations thereof; and the swine is in one or more of a post-weaning phase, growth phase, or finishing phase.

[0007] In another aspect, the present technology provides the use of a swine feed as described herein in any aspect for improving feed conversion measured as feed to gain ratio of the swine compared to a control swine not fed the swine feed, wherein the swine feed comprises a nitrate compound, hydrates thereof, salts thereof, or combinations thereof, and wherein the daily feed intake amount of the nitrate compound, hydrates thereof, salts thereof, or combinations thereof is about 0.02% by weight to less than about 0.1% by weight based on total weight of the swine feed.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] FIG. 1 A shows a plot of the overall feed (kg) to gain (kg) ratio for swine fed Treatments A-F.

[0009] FIG. IB shows a plot of the feed (kg) to gain (kg) ratio for gilts and borrows fed Treatments A-F.

[0010] FIG. 2 A shows a plot of the overall average daily gain (ADG, kg) for swine fed Treatments A-F. [0011] FIG. 2B shows a plot of the overall average daily feed intake (ADFI, kg) for swine fed Treatments A-F.

DETAILED DESCRIPTION

[0012] Reference will now be made in detail to certain aspects of the disclosed subject matter. While the disclosed subject matter will be described in conjunction with the enumerated claims, it will be understood that the exemplified subject matter is not intended to limit the claims to the disclosed subject matter. One aspect described in conjunction with a particular aspect is not necessarily limited to that aspect and can be practiced with any other aspect(s).

[0013] Throughout this document, values expressed in a range format should be interpreted in a flexible manner to include not only the numerical values explicitly recited as the limits of the range, but also to include all the individual numerical values or sub-ranges encompassed within that range as if each numerical value and sub-range is explicitly recited. For example, a range of “about 0.1% to about 5%” or “about 0.1% to 5%” should be interpreted to include not just about 0.1% to about 5%, but also the individual values (e.g., 1%, 2%, 3%, and 4%) and the sub-ranges (e.g., 0.1% to 0.5%, 1.1% to 2.2%, 3.3% to 4.4%) within the indicated range. The statement “about X to Y” has the same meaning as “about X to about Y,” unless indicated otherwise. Likewise, the statement “about X, Y, or about Z” has the same meaning as “about X, about Y, or about Z,” unless indicated otherwise.

[0014] As used herein, the singular forms “a,” “an,” and “the” and similar referents in the context of describing the elements (especially in the context of the following claims) include plural referents unless the context clearly dictates otherwise. For example, reference to “a substituent” encompasses a single substituent as well as two or more substituents, and the like. It is understood that any term in the singular may include its plural counterpart and vice versa, unless otherwise indicated herein or clearly contradicted by context.

[0015] Nothing in the cited references teaches or suggests the claimed process. In addition, it is to be understood that the phraseology or terminology employed herein, and not otherwise defined, is for the purpose of description only and not of limitation. Any use of section headings is intended to aid reading of the document and is not to be interpreted as limiting; information that is relevant to a section heading may occur within or outside of that particular section.

[0016] As used herein, the terms “for example,” “for instance,” “such as,” or “including” are meant to introduce examples that further clarify more general subject matter. Unless otherwise specified, these examples are provided only as an aid for understanding the applications illustrated in the present disclosure, and are not meant to be limiting in any fashion.

[0017] In the methods described herein, the acts can be carried out in a specific order as recited herein. Alternatively, in any aspect(s) disclosed herein, specific acts may be carried out in any order without departing from the principles of the disclosure, except when a temporal or operational sequence is explicitly recited. Furthermore, specified acts can be carried out concurrently unless explicit claim language recites that they be carried out separately or the plain meaning of the claims would require it. For example, a claimed act of doing X and a claimed act of doing Y can be conducted simultaneously within a single operation, and the resulting process will fall within the literal scope of the claimed process.

[0018] The term “about” as used herein can allow for a degree of variability in a value or range, for example, plus or minus within 10%, within 5%, or within 1% of a stated value or of a stated limit of a range, and includes the exact stated value or range.

[0019] The term “substantially” as used herein refers to a majority of, or mostly, as in at least about 50%, 60%, 70%, 80%, 90%, 95%, 96%, 97%, 98%, 99%, 99.5%, 99.9%, 99.99%, or at least about 99.999% or more, or 100%.

[0020] As used herein, the following terms have the following meanings unless expressly stated to the contrary.

[0021] The term “animals” as used in this disclosure includes monogastric and ruminant animals. As used in this disclosure, the term “monogastric” means any organism having a simple single-chambered stomach. Such monogastric animals include, but are not limited to, porcine, equine, avian animals, seafood (aquaculture) animals.

[0022] Porcine monogastric animals refers to domesticated swine (or pigs) and wild boars. Swine include, but are not limited to, feeder pigs and breeder pigs, including piglets, sows, gilts, barrows, and boars. “Gilts” as used herein refers to female pigs intended for slaughter or breeding purposes that have not yet farrowed a litter. “Barrows” as used herein refers to castrated male pigs intended for slaughter, whereas “boars” as used herein refers to intact, sexually mature, male pigs intended for breeding purposes.

[0023] Swine production can be logically separated into a number of phases. Typically, the stages include, breeding and gestation, farrowing, weaning, growing or growth, and finishing or finisher phases. Generally, the stages described herein may vary across geographies as understood by persons skilled in the art, and the definitions provided herein provide exemplary descriptions, that include but are not limited to, weights, ages, and development stages in swine production.

[0024] Breeding and Gestation. The sow is bred during her estrous period. In the phase between weaning the sow and breeding, a special breeding feed can be fed to the sow. After breeding, the sow “gestates” her litter for 113 to 116 days before the piglets are born or “farrowed.” As used herein, the term “gestation” or gestation phase means the 113 to 116 day period when the sow is pregnant from breeding until farrowing.

[0025] Farrowing. The process of giving birth is called farrowing. Typically, sows are moved to a farrowing room a few days prior to farrowing and farrow about eight to fourteen piglets (as a group called a “litter”). The piglets are born weighing about 1.5 kg at birth. As used herein, the term “farrowing” means birth, and the term “farrowing phase” means the period from birth to weaning. The period of time called the transition period is typically seven days pre-farrowing until one to five days post farrowing. The piglets stay with the lactating sow for about 19-35 days after farrowing, during which time the piglets drink milk produced by the lactating sow.

[0026] Weaning. The piglets are weaned from the sow at anywhere from five days to five weeks, with most operations weaning pigs at two to four weeks after farrowing. As used herein, the term “weaning” means the process of separating the piglets from the sow. During a weaning or nursery phase, the piglets remain in the nursery — for example, until about four to eight weeks after farrowing (or in other instances, up to about 18 kg to about 30 kg). “Postweaning” as used herein means the period following the weaning or nursery phase — typically at about six to ten weeks of age where the pig is fed a transitioning diet and before being fed a suitable grower/finishing phase diet based on the pigs age and weight.

[0027] Growing and Finishing. Pigs are normally placed in a grow-fini shing building until they reach market weight, following the weaning (or nursery) phase. “Growing phase” or “growth phase” as used herein refers to the stage where pigs starting from about 35 pounds to 60 pounds (-16-27 kg) are fed to a body weight of about 120 to about 165 pounds (-54-75 kg). “Finishing phase” or “finisher phase” as used herein refers to the stage where pigs are fed from about 120 to 150 pounds (-54-68 kg) are fed to a market body weight — typically about 200 to about 309 pounds (-91-140 kg), and preferably about 243 pounds to about 309 pounds (-110-140 kg).

[0028] As used herein, the term “nitrate compound” refers to any material including one or more nitrate-containing compounds suitable for use in swine feed. [0029] The nitrate compounds as described in any aspect herein may be any suitable nitrate-containing compound. As would be understood by a person of ordinary skill in the art, a suitable nitrate-containing compound may be defined as any physiologically acceptable or tolerated nitrate compound. For example, the nitrate compound may be well-soluble in water, /.<?., the compound has sufficient solubility for bioavailability after administration to the swine. In some aspects, the nitrate compound may be an ionic nitrate compound, preferably an inorganic nitrate salt. Typically, the ionic nitrate salts may include, but are not limited to, sodium nitrate, potassium nitrate, calcium nitrate, magnesium nitrate, ammonium nitrate, or mixtures thereof, all of which are readily soluble in water at standard temperature (e.g., 0°C (32°F)) and pressure (e.g., 1 bar). Preferably, the ionic nitrate salt may be calcium nitrate. The ionic nitrate salts may include different hydrated forms. For example, the ionic nitrate salts may also include double salts (e.g., calcium nitrate and ammonium nitrate). In any aspect described herein, a mixture of two or more different ionic nitrate salts or salt forms may be used in the method.

[0030] While not intending to be limited by any particular theory, it is believed that nitrate is a source for the biological messenger nitric oxide (NO) according to a non- enzymatic pathway for the generation of NO (nitrate-nitrite-NO pathway). Unlike arginine conversion to nitric oxide, nitrate conversion to nitric oxide via the nitrate-nitrite-NO pathway is not dependent upon oxygen levels. It is believed that the release of NO in the animal is important for the control of vascular tone, smooth muscle growth, platelet aggregation and inflammation. The release of NO in the animal is believed to induce vasodilation and increased blood flow and exchange of oxygen. While vasodilation is one biological pathway affected by nitrate supplementation, vasodilation does not account for all improvements observed following nitrate supplementation and can vary based on a number of factors (e.g., species, age, feed, etc.). Accordingly, outcomes can vary across species (or within a species) fed a feed containing nitrates.

[0031] In any aspect described herein, the nitrate compound may be provided as calcium nitrate having the formula Ca(NO3)2. Calcium nitrate is also referred to as calcium dinitrate, Kalksalpeter, nitrocalcite, Norwegian saltpeter, and lime nitrate. Calcium nitrate may be produced by treating limestone with nitric acid, according to the reaction: CaCCh + 2HNO3 Ca(NO 3)2 + CO2 + H2O. Additionally or alternatively, in some aspects, the one or more nitrates may be provided as an inorganic salt of magnesium nitrate hexahydrate having the formula (Mg(NO3)2*6H2O). This product contains 10.8% N from nitrate and 9.5% Mg. [0032] A variety of related complex inorganic salts of calcium nitrate include calcium ammonium nitrate decahydrate and calcium potassium nitrate decahydrate. Calcium ammonium nitrate is a double salt (calcium nitrate and ammonium nitrate) having the formula 5Ca(NO3)2*NH4NO3*10H2O. For example, the calcium ammonium nitrate may be pentacalcium ammonium nitrate decahydrate commercially available from Bri-Chem Supply Limited with the following specification: Ammonium-N (NH4-N): 1.1%; Nitrate-N (NO3-N): 14.4%; Total N: 15.5%; Calcium (Ca): 18.8%. In another example, the calcium nitrate may be BOLIFOR CNF calcium nitrate feed grade having the formula 5Ca(NO3)2*NH4NO3*10H2O commercially available from Yara Phosphates Oy of Helsingborg Sweden. In yet another example the calcium nitrate may have the following specification: Calcium (Ca): 18.9%; Nitrogen (N) 15.5%; pH (10% solution): 6; bulk density (kg/m ³ ): 1050; appearance: prilled; size: <1.0 mm: 2%; 1.0-2.0 mm: 78%; >2 mm: 20%. Exemplary formulations of calcium nitrate lacking ammonia include Ca(NO3)2*4H2O. An exemplary anhydrous air-stable derivative of calcium nitrate may include urea complex Ca(NO3)2’4[OC(NH ₂ ) ₂ ].

[0033] Antioxidants, when included in swine diets, are known to protect cells from damage caused by free radicals and peroxides. There are different types of antioxidants available for feeding swine, including natural dietary antioxidants. For example, natural antioxidants may include, but are not limited to, vitamins, minerals, carotenoids, and polyphenols.

[0034] In any aspect described herein, the antioxidant preferably includes polyphenols. Suitable polyphenol sources may include, but are not limited to, fruits (such as apples, apricots, currants, blackberries, blueberries, cherries, chokeberries, cranberries, dates, elderberries, gooseberries, grapes, kiwis, lemons, lingonberries, limes, mangoes, marionberries, nectarines, olives, oranges, peaches, pears, plums, pomegranates, quinces, raspberries, rhubarb, strawberries, tomatoes, or mixtures thereof), vegetables (such as artichokes, broccoli, celery, com, eggplant, fennel, garlic, greens, kohlrabi, leeks, lovage, onions, parsnips, peppers, spinach, red cabbage, rutabagas, scallions, shallots, sweet potatoes, watercress, or mixtures thereof), legumes (such as chick peas, beans, lentils, snap beans, English peas, green peas, fava beans, or mixtures thereof), nuts (such as almonds, cashews, hazelnuts, pecans, peanuts, pistachios, walnuts, or mixtures thereof), seeds (such as fruit seeds, flax seeds, pumpkin seeds, sunflower seeds, or mixtures thereof), teas (such as green tea, black tea, oolong tea, Earl Gray tea, Ceylon tea, Darjeeling tea, or mixtures thereof), herbs and spices (such as basil, chives, capers, cinnamon, curry, dill weed, horseradish, oregano, parsley, rosemary, sage, tarragon, thyme, or mixtures thereof), tree barks (such as arjuna bark, aspen bark, birch bark, conifer bark, eucalyptus bark, maple bark, or mixtures thereof), or mixtures thereof. Preferably, the antioxidant may include polyphenols from polyphenol sources including onion extract, grape seed extract, rosemary extract, or mixtures thereof.

[0035] A polyphenol source suitable for use in any aspect of the present technology may include commercially available sources. For example, a polyphenol source is commercially available under the trade name PROVIOX 50, available from Cargill, Incorporated, Wayzata, MN, USA. The formulation of PROVIOX 50 includes a blend of polyphenol grape seed and skin extracts, onion extracts, and rosemary extracts. PROVIOX 50 is a standardized product for its total polyphenol content. PROVIOX 50 contains sources of polyphenols with antioxidant properties. In any aspect, the antioxidant that includes polyphenols is PROVIOX 50.

[0036] In any aspect described herein, the term “swine feed” refers to a feed ration produced for consumption by swine. The term “compound feed” as used in any aspect described herein refers to a swine feed blended to include two or more ingredients which assist in meeting certain daily nutritional requirements of swine, preferably swine in one or more of a post-weaning, growth, or finishing phase. The swine feed may be a complete swine feed according to any aspect described herein. The term “complete feed” as used in any aspect described herein refers to a swine feed having a nutritionally balanced blend of ingredients designed as the sole ration to provide all the daily nutritional requirements of a swine to maintain life and promote production without any additional substances being consumed except for water. The swine feed may also be a concentrate swine feed according to any aspect described herein. The term “concentrate feed” or “concentrate swine feed” as used herein in any aspect described herein refers to a swine feed that typically includes a protein source blended with supplements or additives or vitamins, trace minerals, other micro ingredients, macro minerals, etc. to provide a part of the ration for the swine. The concentrate feed may be fed along with other ingredients. The swine feed may include a premix according to any aspect described herein. The term “premix” as used in any aspect described herein refers to a blend of primarily vitamins and/or minerals along with appropriate carriers. The swine feed may also include a base mix according to any aspect described herein. The term “base mix” as used in any aspect described herein refers to a blend containing vitamins, trace minerals and/or other micro ingredients plus macro minerals such as calcium, phosphorus, sodium, magnesium, and potassium, vitamins, or combinations thereof. The swine feed may be a feed “supplement.” As used herein in any aspect, the terms “feed supplement” or “swine feed supplement” refers to a concentrated additive premix that includes the active ingredients, which premix or supplement may be added to a swine’s feed or ration to form a supplemented feed in accordance with the present technology. As used herein in any aspect, the term “additive” or “feed additive” refers to an ingredient such as a protein source, salt, mineral, additive, or buffer that is added to a swine feed. For example, an additive may include, but is not limited to, calcium, zinc, manganese, copper, iodine, cobalt, selenium, other trace ingredients, or mixtures thereof.

[0037] Swine production efficiency may be defined in different ways. One indicator is feed conversion ratio (FCR), or the ratio between feed intake (kg) and body weight gain (kg) (feed:gain ratio). Alternatively, FCR may be interchangeably represented as the ratio between body weight gain (kg) of a pig and feed intake (kg) (gaimfeed ratio). For pigs in one or more of a post-weaning, growth, or finishing phase, feed conversion is adversely impacted when the supply of nutrients is below levels generally required for growth. Improvements in feed conversion (/.< ., feed efficiency) are also cost effective, as less feed is needed per animal to achieve market weights.

[0038] Evidence from humans suggest that consumption of nitrate may reduce resting metabolic rate, which suggests there is a potential for more efficient energy utilization (e.g., growth, exercise). (Larsen et al., Am. J. Clin. Nutr., 2014, 99:843-50). However, a metaanalysis found that dietary nitrate supplementation did not significantly decrease resting metabolic rate. (Pawlak-Chaouch et al., Nitric Oxide, 2016, 53:65-67). While there is not clarity in differences in outcome of the two studies, it is believed that the amount of nitrate supplementation or nitrate content of individuals daily diet may have contributed to the differences observed. Based upon a review by Ghasemi (EXCLI Journal, 2022, 21 :470-486), up to 10% of nitric oxide produced in human bodies come from an exogenous source (e.g., diet, environment).

[0039] While the above studies provide limited, yet inconclusive, insight on the potential effects of nitrate consumption in humans, much is unknown with respect to the effect of exogenous nitrate consumption on the growth of pigs, including appropriate intake levels of exogenous nitrate. Although pigs are omnivores like humans, most domestic pigs (i.e., pigs in swine production) are fed grain and oilseed diets devoid of leafy -green vegetables that may serve as nitrate sources, which suggests that overall nitrate intake is lower than historic values in both feral pigs and humans.

[0040] The present inventors discovered inclusion of nitrate in the daily feed intake of swine during one or more of a post-weaning, growth, or finishing phase significantly improved feed efficiency, measured as feed:gain (or gaimfeed) ratio, of the swine compared to swine fed a conventional feed. Surprisingly, the inventors discovered feed efficiency is quadratically effected in relation to the daily amount of nitrate fed to swine during postweaning, growth, and/or finishing phases. Described herein are methods for improving the feed efficiency of swine by feeding swine a feed that includes a nitrate compound.

[0041] In one aspect, the present technology provides a method for improving feed efficiency (i.e., feed conversion ratio), the method includes feeding to swine about 70 mg/kg bodyweight (BW) per day or less of a nitrate compound, hydrates thereof, salts thereof, or combinations thereof; wherein the method improves feed conversion measured as feed to gain ratio (feed:gain) of the swine compared to a control swine not fed the nitrate compound, hydrates thereof, salts thereof, or combinations thereof; and wherein the swine is in one or more of a post-weaning phase, growth phase, or finishing phase.

[0042] Generally, swine may be in one or more of a post-weaning, growth, or finishing phase encompasses gilts, barrows, boars, or combinations thereof. During swine production, gilts may be housed separately from barrows and/or boars during post-weaning, growth, and/or finishing phases. In any aspect, the swine may include gilts, barrows, boars, or combinations thereof. In any aspect, the swine may be gilts. In any aspect, the swine may be barrows. In any aspect, the swine may be boars.

[0043] In any aspect, the swine may be fed the nitrate compound, hydrates thereof, salts thereof, or combinations thereof during a growth phase, finishing phase, or combination thereof. In any aspect, the swine may be fed the nitrate compound, hydrates thereof, salts thereof, or combinations thereof during a growth phase. In any aspect, the swine may be fed the nitrate compound, hydrates thereof, salts thereof, or combinations thereof during a finishing phase.

[0044] The method includes feeding about 70 mg/kg BW per day or less of the nitrate compound to the swine. In any aspect, the amount of nitrate compound fed to the swine may be about 5 mg/kg BW per day to about 70 mg/kg BW per day, about 5 mg/kg BW per day to about 55 mg/kg BW per day, about 10 mg/kg BW per day to about 45 mg/kg BW per day, about 12 mg/kg BW per day to about 40 rng/kg BW per day, or any range including and/or in between any two of the preceding values. For example, suitable amounts of the nitrate compound fed to the swine may include about 5 mg/kg BW per day, about 10 mg/kg BW per day, about 15 mg/kg BW per day, about 20 mg/kg BW per day, about 25 mg/kg BW per day, about 30 mg/kg BW per day, about 35 mg/kg BW per day, about 40 mg/kg BW per day, about 45 mg/kg BW per day, about 50 mg/kg BW per day, about 55 mg/kg BW per day, about 60 mg/kg BW per day, about 65 mg/kg BW per day, about 70 mg/kg BW per day, or any range including and/or in between any two of the preceding values.

[0045] In any aspect, the swine may be fed a daily feed intake comprising an amount of nitrate in a range of about 0.02% by weight to less than about 0.10% by weight based on total weight of a swine feed. In any aspect, the daily feed intake amount of nitrate fed to the swine may be in a range of about 0.02% by weight to about 0.09% by weight based on total weight of the swine feed. In any aspect, the daily feed intake amount of nitrate fed to the swine may be about 0.03% by weight to about 0.09% by weight based on total weight of the swine feed. In any aspect, the daily feed intake amount of nitrate fed to the swine may be about 0.03% by weight to about 0.08% by weight based on total weight of the swine feed. For example, suitable amounts of nitrate compound present in the swine’s daily feed intake may be about 0.02% by weight (“wt%”), about 0.025 wt%, about 0.03 wt%, about 0.035 wt%, about 0.04 wt%, about 0.045 wt%, about 0.05 wt%, about 0.055 wt%, about 0.06 wt%, about 0.065 wt%, about 0.07 wt%, about 0.075 wt%, about 0.08 wt%, about 0.085 wt%, about 0.09 wt%, or any range including and/or in between any two of the preceding values.

[0046] In any aspect, the nitrate compound may include an ionic nitrate salt as described herein. For example, the nitrate compound may include an ionic nitrate salt selected from sodium nitrate, potassium nitrate, calcium nitrate, magnesium nitrate ammonium nitrate, or mixtures thereof. In any aspect, the nitrate compound may be calcium nitrate, complex inorganic salts of calcium nitrate, hydrates thereof (e.g., calcium nitrate dihydrate, calcium nitrate tetrahydrate, calcium nitrate decahydrate), or mixtures thereof. Preferably, the nitrate compound may be calcium ammonium nitrates, or hydrates thereof (e.g. , 5Ca(NO ₃ )2«NH4NO3«10H2O).

[0047] In any aspect, the nitrate compound may also be provided by a variety of plant ingredients according to alternative aspects. For example, such plant ingredients may include, but are not limited to, leafy greens such as spinach, arugula, beetroot, or mixtures thereof. Preferably, the plant ingredient is beetroot. Beetroot has an inorganic nitrate content typically ranging from 110 to 3670 mg nitrate/kg.

[0048] The method of the present technology improves feed conversion measured as feed to gain ratio compared to a control swine not fed nitrate compounds in amounts of 70 mg/kg BW or less per day. The feed to gain ratio is a ratio of the amount of feed consumed by the swine per body weight (kg) gained.

[0049] In any aspect, the method improves the feed to gain ratio (feed:gain) of the swine by at least about 0.5% compared to a control swine not fed nitrate compounds in amounts of 70 mg/kg BW or less per day. In any aspect, the method improves the feed to gain ratio (feed:gain) of the swine by at least about 1% compared to a control swine not fed nitrate compounds in amounts of 70 mg/kg BW or less per day. In any aspect, the method improves the feed:gain of the swine by about 1% to about 4% compared to a control swine not fed nitrate compounds in amounts of 70 mg/kg BW or less per day. In any aspect, the method improves feed:gain by about 0.5%. In any aspect, the method improves feed:gain by about 1%. In any aspect, the method improves feed:gain by about 1.5%. In any aspect, the method improves feed:gain by about 2%. In any aspect, the method improves feed:gain by about 2.5%. In any aspect, the method improves feed:gain by about 3%. In any aspect, the method improves feed:gain by about 4%.

[0050] The improvement in feed conversion observed in the present technology may also be expressed in terms of the percentage of feed intake reduction. In any aspect, the swine may have a feed intake reduction of about 0.5% to about 4% less feed (kg) per kg of body weight gained compared to a control swine not fed the nitrate compound, hydrates thereof, salts thereof, or combinations thereof. For example, the feed intake reduction may be about 0.5%, about 0.6%, about 0.7%, about 0.8%, about 0.9%, about 1.0%, about 1.2%, about 1.4%, about 1.6%, about 1.8%, about 2.0%, about 2.2%, about 2.4%, about 2.6%, about 2.8%, about 3.0%, about 3.2%, about 3.4%, about 3.6%, about 3.8%, about 4.0%, or any range including and/or in between any two of the preceding values.

[0051] The method may further include feeding the swine antioxidants that include polyphenols (e.g., quercetin). Polyphenols are known to those of skill in the art for their free radical scavenging function. Without being bound by any particular theory, it is believed that dietary polyphenols at gastric pH may enhance the formation of nitric oxide. (Rocha et al., Food Funct., 2014, 5: 1646-1652). For example, it has been reported that dietary polyphenols activate the endothelial nitric oxide synthase pathway, which may contribute to the formation of nitric oxide. (Vilahur et al., Rev. Esp. Cardiol., 2015, 68[3] :216-225).

[0052] Suitable sources of polyphenols, as described herein, may include polyphenols extracted from fruits, vegetables, legumes, nuts, seeds, tea, herbs, spices, tree barks, or mixtures thereof. In any aspect, the polyphenols may be from polyphenol sources including onion extract, grape seed extract, grape skin extract, rosemary extract, or mixtures thereof. For example, the polyphenols may be PROVIOX 50 (Cargill, Incorporated).

[0053] The polyphenols as described herein may be fed to the swine in an amount of about 1 ppm to about 500 ppm per day. Suitable amounts of the polyphenols may include about 1 ppm to about 500 ppm, about 5 ppm to about 500 ppm, about 10 ppm to about 500 ppm, about 50 ppm to about 300 ppm, about 75 ppm to about 250 ppm, about 90 ppm to about 150 ppm, or any range including and/or in between any two of the preceding values.

[0054] In any aspect, the antioxidants may further include natural antioxidants, other than polyphenols. For example, the antioxidants may include vitamins, minerals, carotenoids, or mixtures thereof.

[0055] Vitamins may include, but are not limited to, vitamin A (including vitamin A sources such as vitamin A supplement, vitamin A oil, etc.) vitamin Bl, vitamin B2, vitamin B3, vitamin B4, vitamin B5, vitamin B6, vitamin B7, vitamin B8, vitamin B9, vitamin B 12, vitamin C, Vitamin D, (including vitamin D sources such as vitamin D supplement, etc.), vitamin E (including vitamin E sources such as Vitamin E supplement), vitamin K, and other vitamin product ingredients (including riboflavin, vitamin D3 supplement, niacin, betaine, choline chloride, tocopherol, inositol, etc.). In any aspect, the vitamins may preferably be vitamins E, vitamins C, or combinations thereof.

[0056] Minerals may include, for example and without limitation, calcium, chlorine (as chloride ions), magnesium, phosphorus, potassium, sodium, sulfur, cobalt, copper, chromium, iodine, manganese, molybdenum, nickel, selenium vanadium, zinc, or mixtures thereof. In any aspect, the minerals may preferably be selenium, zinc, manganese, copper, or mixtures thereof.

[0057] In another aspect, the present technology provides a method for feeding swine, the method comprising: feeding swine a swine feed comprising a nitrate compound, hydrates thereof, salts thereof, or combinations thereof; wherein: the swine is fed a daily feed intake comprising an amount of nitrate is in a range of about 0.02% by weight to less than about 0.10% by weight based on total weight of the swine feed; the method improves feed conversion measured as feed to gain ratio of the swine compared to a control swine not fed the nitrate compound, hydrates thereof, salts thereof, or combinations thereof; and the swine is in one or more of a post-weaning phase, growth phase, or finishing phase.

[0058] In any aspect, the swine may be fed a daily feed intake comprising an amount of nitrate in a range of about 0.02% by weight to less than about 0.10% by weight based on total weight of a swine feed. In any aspect, the daily feed intake amount of nitrate fed to the swine may be in a range of about 0.02% by weight to about 0.09% by weight based on total weight of the swine feed. In any aspect, the daily feed intake amount of nitrate fed to the swine may be about 0.03% by weight to about 0.09% by weight based on total weight of the swine feed. In any aspect, the daily feed intake amount of nitrate fed to the swine may be about 0.03% by weight to about 0.08% by weight based on total weight of the swine feed. For example, suitable amounts of nitrate compound present in the swine’s daily feed intake may be about 0.02% by weight (“wt%”), about 0.025 wt%, about 0.03 wt%, about 0.035 wt%, about 0.04 wt%, about 0.045 wt%, about 0.05 wt%, about 0.055 wt%, about 0.06 wt%, about 0.065 wt%, about 0.07 wt%, about 0.075 wt%, about 0.08 wt%, about 0.085 wt%, about 0.09 wt%, or any range including and/or in between any two of the preceding values.

[0059] In any aspect, the nitrate compound may include an ionic nitrate salt as described herein. For example, the nitrate compound may include an ionic nitrate salt selected from sodium nitrate, potassium nitrate, calcium nitrate, magnesium nitrate ammonium nitrate, or mixtures thereof. In any aspect, the nitrate compound may be calcium nitrate, complex inorganic salts of calcium nitrate, hydrates thereof (e.g., calcium nitrate dihydrate, calcium nitrate tetrahydrate, calcium nitrate decahydrate), or mixtures thereof. Preferably, the nitrate compound may be calcium ammonium nitrates, or hydrates thereof (e.g. , 5Ca(NO ₃ )2«NH4NO3«10H2O). [0060] In any aspect, the nitrate compound may also be provided by a variety of plant ingredients according to alternative aspects. For example, such plant ingredients may include, but are not limited to, leafy greens such as spinach, arugula, beetroot, or mixtures thereof. Preferably, the plant ingredient is beetroot. Beetroot has an inorganic nitrate content typically ranging from 110 to 3670 mg nitrate/kg.

[0061] The method of the present technology improves feed conversion measured as feed to gain ratio compared to a control swine not fed nitrate compounds in amounts of 70 mg/kg BW or less per day. The feed to gain ratio is a ratio of the amount of feed consumed by the swine per body weight (kg) gained.

[0062] In any aspect, the method improves the feed to gain ratio (feed:gain) of the swine by at least about 0.5% compared to a control swine not fed the swine feed. In any aspect, the method improves the feed to gain ratio (feed:gain) of the swine by at least about 1% compared to a control swine not fed the swine feed. In any aspect, the method improves the feed:gain of the swine by about 1% to about 4% compared to a control swine not fed the swine feed. In any aspect, the method improves feed:gain by about 0.5%. In any aspect, the method improves feed:gain by about 1%. In any aspect, the method improves feed:gain by about 1.5%. In any aspect, the method improves feed:gain by about 2%. In any aspect, the method improves feed:gain by about 2.5%. In any aspect, the method improves feed:gain by about 3%. In any aspect, the method improves feed:gain by about 4%.

[0063] The improvement in feed conversion observed in the present technology may also be expressed in terms of the percentage of feed intake reduction. In any aspect, the swine may have a feed intake reduction of about 0.5% to about 4% less feed (kg) per kg of body weight gained compared to a control swine not fed the swine feed. For example, the feed intake reduction may be about 0.5%, about 0.6%, about 0.7%, about 0.8%, about 0.9%, about 1.0%, about 1.2%, about 1.4%, about 1.6%, about 1.8%, about 2.0%, about 2.2%, about 2.4%, about 2.6%, about 2.8%, about 3.0%, about 3.2%, about 3.4%, about 3.6%, about 3.8%, about 4.0%, or any range including and/or in between any two of the preceding values.

[0064] In any aspect, the swine feed may be a premix, a feed additive, a feed supplement, a compound feed, or a complete feed as described herein. In any aspect, the swine feed may be a composition that includes an amount of the nitrate compound, hydrates thereof, salts thereof, or combinations thereof fed to the swine before, during, or after providing the swine a feed that does not include nitrate. For example, the swine feed comprising the nitrate compound, hydrates thereof, salts thereof, or combinations thereof may be provided in a supplement separately from the feed or is provided in a supplement that is mixed with the feed. As would be understood by a person skilled in the art, the amount of the nitrate compound, hydrates thereof, salts thereof, or combinations thereof would typically be different from the final swine feed, /.< ., the supplement may include a higher concentration of the nitrate compound compared to the final swine feed itself such that the daily feed intake of the swine fed the final swine feed is from about 0.02% by weight to less than about 0.1% by weight based on total weight of the swine feed.

[0065] The method may further include feeding the swine antioxidants that include polyphenols (e.g., quercetin). Polyphenols are known to those of skill in the art for their free radical scavenging function. Suitable sources of polyphenols, as described herein, may include polyphenols extracted from fruits, vegetables, legumes, nuts, seeds, tea, herbs, spices, tree barks, or mixtures thereof. In any aspect, the polyphenols may be from polyphenol sources including onion extract, grape seed extract, grape skin extract, rosemary extract, or mixtures thereof. For example, the polyphenols may be PROVIOX 50 (Cargill, Incorporated).

[0066] The polyphenols as described herein may be fed to the swine as part of the swine feed in an amount of about 1 ppm to about 500 ppm per day. Suitable amounts of the polyphenols may include about 1 ppm to about 500 ppm, about 5 ppm to about 500 ppm, about 10 ppm to about 500 ppm, about 50 ppm to about 300 ppm, about 75 ppm to about 250 ppm, about 90 ppm to about 150 ppm, or any range including and/or in between any two of the preceding values.

[0067] In any aspect, the antioxidants may further include natural antioxidants, other than polyphenols. For example, the antioxidants may include vitamins, minerals, carotenoids, or mixtures thereof.

[0068] Vitamins may include, but are not limited to, vitamin A (including vitamin A sources such as vitamin A supplement, vitamin A oil, etc.) vitamin Bl, vitamin B2, vitamin B3, vitamin B4, vitamin B5, vitamin B6, vitamin B7, vitamin B8, vitamin B9, vitamin B 12, vitamin C, Vitamin D, (including vitamin D sources such as vitamin D supplement, etc.), vitamin E (including vitamin E sources such as Vitamin E supplement), vitamin K, and other vitamin product ingredients (including riboflavin, vitamin D3 supplement, niacin, betaine, choline chloride, tocopherol, inositol, etc.). In any aspect, the vitamins may preferably be vitamins E, vitamins C, or combinations thereof.

[0069] Minerals may include, for example and without limitation, calcium, chlorine (as chloride ions), magnesium, phosphorus, potassium, sodium, sulfur, cobalt, copper, chromium, iodine, manganese, molybdenum, nickel, selenium vanadium, zinc, or mixtures thereof. In any aspect, the minerals may preferably be selenium, zinc, manganese, copper, or mixtures thereof.

[0070] In any aspect, the swine may include gilts, barrows, boars, or combinations thereof. In any aspect, the swine may be gilts. In any aspect, the swine may be barrows. In any aspect, the swine may be boars.

[0071] In any aspect, the swine may be fed the feed during a growth phase, finishing phase, or combination thereof. In any aspect, the swine may be fed the feed during a growth phase. In any aspect, the swine may be fed the feed during a finishing phase.

[0072] In another aspect, the present technology provides the use of a swine feed as described herein in any aspect for improving feed conversion measured as feed to gain ratio of the swine compared to a control swine not fed the swine feed, wherein the swine feed comprises a nitrate compound, hydrates thereof, salts thereof, or combinations thereof, and wherein the daily feed intake amount of the nitrate compound, hydrates thereof, salts thereof, or combinations thereof is about 0.02% by weight to less than about 0.1% by weight based on total weight of the swine feed.

[0073] In any aspect, use of the swine feed improves feed to gain ratio (feed:gain) of the swine by at least about 0.5% compared to a control swine not fed the swine feed. In any aspect, use of the swine feed as described herein improves the feed to gain ratio (feed:gain) of the swine by at least about 1% compared to a control swine not fed the swine feed. In any aspect, use of the swine feed improves the feed:gain of the swine by about 1% to about 4% compared to a control swine not fed the swine feed. In any aspect, use of the swine feed improves feed:gain by about 0.5%. In any aspect, the method improves feed:gain by about 1%. In any aspect, the method improves feed:gain by about 1.5%. In any aspect, use of the swine feed improves feed:gain by about 2%. In any aspect, use of the swine feed improves feed:gain by about 2.5%. In any aspect, use of the swine feed improves feed:gain by about 3%. In any aspect, the method improves feed:gain by about 4%. [0074] Use of the swine feed as described herein in any aspect provides improvement in feed conversion expressed in terms of the percentage of feed intake reduction. In any aspect, the swine may have a feed intake reduction of about 0.5% to about 4% less feed (kg) per kg of body weight gained compared to a control swine not fed the swine feed. For example, the feed intake reduction may be about 0.5%, about 0.6%, about 0.7%, about 0.8%, about 0.9%, about 1.0%, about 1.2%, about 1.4%, about 1.6%, about 1.8%, about 2.0%, about 2.2%, about 2.4%, about 2.6%, about 2.8%, about 3.0%, about 3.2%, about 3.4%, about 3.6%, about 3.8%, about 4.0%, or any range including and/or in between any two of the preceding values.

[0075] In any aspect, the use of the swine feed includes feeding the swine feed to swine in one or more of a post-weaning phase, growth phase, finishing phase, or combination thereof. In any aspect, the swine may be fed the feed during a growth phase. In any aspect, the swine may be fed the feed during a finishing phase.

[0076] In any aspect, the swine may include gilts, barrows, boars, or combinations thereof. In any aspect, the swine may be gilts. In any aspect, the swine may be barrows. In any aspect, the swine may be boars.

[0077] The present invention, thus generally described, will be understood more readily by reference to the following examples, which are provided by way of illustration and are not intended to be limiting of the present invention.

EXAMPLES

[0078] Example 1: Effect of nitrate on feed efficiency. A trial was conducted to evaluate six different levels of nitrate (NO ) compounds (i.e., Ca(NCh)2) for its technical performance in improving feed:gain ratio in grower and finisher pigs.

[0079] The trial was conducted in the grower-finisher unit at Cargill Animal Nutrition and Health Global Innovation Center in Velddriel, The Netherlands. One hundred and forty- four pigs (gilts & barrows) at an average weight of about 52.4 kg were allocated to one of six treatments (n=8, 3 pigs per pen). Pigs were blocked by sex and location within the room. Experimental feed diets (Treatments A-F) were fed in two phases (phase 1 = 0-21 d; phase 2 = 21-70 d). The table below provides daily intake of nitrate in the experimental feed (wt% per day) and the dosing range (mg/kg BW/day) of nitrate consumed by the gilts & barrows during the trial.

[0080] The measured daily dosing amounts of nitrate (NCh", mg/kg BW/day) provides further insight into the improved feed to gain ratio. Pig weights reported in this study started at 52 kg and ended at 120 kg, where mg/kg BW/day dosing of nitrate changed as the weight of the pigs changed and daily feed intake changes. Indeed, dosing also changes outside the weight ranges used in this study and is dependent on whether the pig has a low intake or high intake genetic line. The table below shows lighter pigs having a higher nitrate intake compared to heavier pigs on a mg/kg BW/day basis (reaching nearly 70 mg/kg BW/day for a 25 kg pig).

[0081] As shown in FIG. 1A, a quadratic effect was observed overall for swine fed the treatment containing calcium nitrate (nitrate between 0.02 wt% to 0.1 wt%). Surprisingly, swine fed lower levels of nitrate in their daily feed intake (Treatments B-E) exhibited improved feed conversion when compared to swine fed a control feed (Treatment A), where swine fed Treatments B-E exhibited a decrease in the total amount of feed (kg) consumed per kg body weight gained of about 0.5% to about 1.3% (FIG. 1A). In contrast, the overall feed conversion sharply increased at the highest nitrate inclusion level of 0.1 wt% per day (Treatment F), where swine fed Treatment F exhibited an increase in the amount of feed (kg) consumed per kg body weight gained of about 1.6% compared to swine fed the control feed (Treatment A).

[0082] As shown in FIG. IB, gilts showed a higher improvement in feed conversion when fed lower amounts of nitrate (Treatments B-E), showing a decrease in the total amount of feed (kg) consumed per kg body weight gained of about 1.1% to about 3.3% compared to swine fed the control feed (Treatment A). Barrows showed a similar improvement when fed nitrate at lower levels, exhibiting a decrease in the total amount of feed (kg) consumed per kg body weight gained of up to about 1.4%. Feed conversion declined in both gilts and barrows at higher levels of nitrate inclusion. Accordingly, the present examples demonstrate that feed conversion is improved during growth and/or finishing phases of swine when fed low levels of nitrate as part of the swine’s daily feed intake.

[0083] Each of the non-limiting aspects above can stand on its own, or can be combined in various permutations or combinations with one or more of the other aspects or other subject matter described in this document. While certain aspects have been illustrated and described, a person with ordinary skill in the art, after reading the foregoing specification can effect changes, substitutions of equivalents and other types of alterations to the present technology as set forth herein. Each aspect and aspect described above can also have included or incorporated therewith such variations or aspects as disclosed in regard to any or all of the other aspects and aspects.

[0084] As shown in FIG. 2A and 2B, no effects were observed with respect to average daily gain (ADG, kg) or average daily feed intake (ADFI, kg) for swine fed Treatments A-F.

[0085] Exemplary Aspects:

[0086] The following exemplary aspects are provided, the numbering of which is not to be construed as designating levels of importance:

[0087] Paragraph (Para.) A: A method for improving feed efficiency in swine, the method comprising: feeding swine about 70 mg/kg bodyweight (BW) per day or less of a nitrate compound, hydrates thereof, salts thereof, or combinations thereof; wherein the method improves feed conversion measured as feed to gain ratio of the swine compared to a control swine not fed the nitrate compound, hydrates thereof, salts thereof, or combinations thereof; and wherein the swine is in one or more of a post- weaning phase, growth phase, or finishing phase. [0088] Para. B: The method of Para. B, wherein the swine comprises gilts, barrows, boars, or combinations thereof.

[0089] Para. C: The method of Para. A or B, wherein the swine comprises gilts.

[0090] Para. D: The method of Para. A or B, wherein the swine comprises barrows or boars.

[0091] Para. E: The method of any one of Paras. A-D comprising feeding the swine about 5 mg/kg BW per day to about 55 mg/kg per day of the nitrate compound, hydrates thereof, salts thereof, or combinations thereof.

[0092] Para. F: The method of any one of Paras. A-E comprising feeding the swine about 10 mg/kg BW per day to about 45 mg/kg BW per day of the nitrate compound, hydrates thereof, salts thereof, or combinations thereof.

[0093] Para. G: The method of any one of Paras. A-F comprising feeding the swine about 12 mg/kg BW per day to about 35 mg/kg BW per day of the nitrate compound, hydrates thereof, salts thereof, or combinations thereof.

[0094] Para. H: The method of any one of Paras. A-G, wherein the swine is in a growth phase or a finishing phase.

[0095] Para. I: The method of any one of Paras. A-H, wherein the swine is fed a daily feed intake comprising an amount of nitrate in a range of about 0.02% by weight to less than about 0.10% by weight based on total weight of a swine feed.

[0096] Para. J: The method of Para. I, wherein the daily feed intake amount of nitrate is in a range of about 0.03% by weight to about 0.08% by weight of based on total weight of a swine feed.

[0097] Para. K: The method of any one of Paras. A- J, wherein the nitrate compound, hydrates thereof, salts thereof, or combinations thereof comprises ionic nitrate salts.

[0098] Para. L: The method of any one of Paras. A-K, wherein the nitrate compound, hydrates thereof, salts thereof, or combinations thereof comprises sodium nitrate, potassium nitrate, calcium nitrate, magnesium nitrate, ammonium nitrate, or mixtures thereof.

[0099] Para. M: The method of any one of Paras. A-L, wherein the nitrate compound, hydrates thereof, salts thereof, or combinations thereof comprises calcium nitrate, complex inorganic salts of calcium nitrate, or mixtures thereof.

[0100] Para. N: The method of any one of Paras. A-M, wherein the nitrate compound, hydrates thereof, salts thereof, or combinations thereof comprises calcium ammonium nitrate, pentacalcium ammonium nitrate decahydrate, or combinations thereof. [0101] Para. O: The method of any one of Paras. A-N, wherein the method improves the feed to gain ratio of the swine by at least about 1% compared to a control swine not fed the nitrate compound, hydrates thereof, salts thereof, or combinations thereof.

[0102] Para. P: The method of any one of Paras. A-O, wherein the method improves the feed to gain ratio of the swine by about 1% to about 4% compared to a control swine not fed the nitrate compound, hydrates thereof, salts thereof, or combinations thereof.

[0103] Para. Q: The method of any one of Paras. A-P, wherein the swine fed the nitrate compound, hydrates thereof, salts thereof, or combinations thereof consume about 0.5% to about 4% less feed (kg) per kg body weight gain compared to the amount of feed (kg) per kg body weight gain in a control swine not fed the nitrate compound, hydrates thereof, salts thereof, or combinations thereof.

[0104] Para. R: The method of Para. C, wherein gilts fed the nitrate compound, hydrates thereof, salts thereof, or combinations thereof consume about 1.5% to about 4% less feed (kg) per kg body weight gain compared to amount of feed (kg) per kg body weight in a control swine not fed the nitrate compound, hydrates thereof, salts thereof, or combinations thereof.

[0105] Para. S: The method of any one of Paras. A-R further comprising feeding the swine polyphenols as part of the feed diet.

[0106] Para. T: The method of Para. S, wherein the polyphenols comprise polyphenols sources selected from the group consisting of onion extract, grape seed extract, grape skin extract, rosemary extract, and mixtures thereof.

[0107] Para. U: A method for feeding swine, the method comprising: feeding swine a swine feed comprising a nitrate compound, hydrates thereof, salts thereof, or combinations thereof; wherein: the swine is fed a daily feed intake comprising an amount of nitrate is in a range of about 0.02% by weight to less than about 0.10% by weight based on total weight of the swine feed; the method improves feed conversion measured as feed to gain ratio of the swine compared to a control swine not fed the nitrate compound, hydrates thereof, salts thereof, or combinations thereof; and the swine is in one or more of a post- weaning phase, growth phase, or finishing phase. [0108] Para. V: The method of Para. U, wherein the daily feed intake amount of nitrate is in a range of about 0.03% by weight to about 0.08% by weight of based on total weight of a swine feed.

[0109] Para. W: The method of Para. U or V, wherein the nitrate compound, hydrates thereof, salts thereof, or combinations thereof comprises ionic nitrate salts.

[0110] Para. X: The method of any one of Paras. U-W, wherein the nitrate compound, hydrates thereof, salts thereof, or combinations thereof comprises sodium nitrate, potassium nitrate, calcium nitrate, magnesium nitrate, ammonium nitrate, or mixtures thereof.

[0111] Para. Y: The method of any one of Paras. U-X, wherein the nitrate compound, hydrates thereof, salts thereof, or combinations thereof comprises calcium nitrate, complex inorganic salts of calcium nitrate, or mixtures thereof.

[0112] Para. Z: The method of any one of Paras. U-Y, wherein the nitrate compound, hydrates thereof, salts thereof, or combinations thereof comprises calcium ammonium nitrate, pentacalcium ammonium nitrate decahydrate, or combinations thereof.

[0113] Para. AA: The method of any one of Paras. U-Z, wherein the method improves the feed to gain ratio of the swine by at least about 1% compared to a control swine not fed the nitrate compound, hydrates thereof, salts thereof, or combinations thereof.

[0114] Para. AB: The method of any one of Paras. U-AA, wherein the method improves the feed to gain ratio of the swine by about 1% to about 4% compared to a control swine not fed the nitrate compound, hydrates thereof, salts thereof, or combinations thereof. [0115] Para. AC: The method of any one of Paras. U-AB, wherein the swine fed the nitrate compound, hydrates thereof, salts thereof, or combinations thereof consume about 0.5% to about 4% less feed (kg) per kg body weight gain compared to the amount of feed (kg) per kg body weight gain in a control swine not fed the nitrate compound, hydrates thereof, salts thereof, or combinations thereof.

[0116] Para. AD: The method of Para. AC, wherein the swine comprises gilts, and wherein gilts fed the nitrate compound, hydrates thereof, salts thereof, or combinations thereof consume about 1.5% to about 4% less feed (kg) per kg body weight gain compared to amount of feed (kg) per kg body weight in a control swine not fed the nitrate compound, hydrates thereof, salts thereof, or combinations thereof.

[0117] Para. AE: The method of any one of claims Paras. U-AD further comprising feeding the swine polyphenols as part of the feed diet. [0118] Para. AF: The method of Para. AE, wherein the polyphenols comprise polyphenols sources selected from the group consisting of onion extract, grape seed extract, grape skin extract, rosemary extract, and mixtures thereof.

[0119] Para. AG: The method of any one of Paras. U-AF, wherein the swine is in a growth phase or a finishing phase.

[0120] Para. AH: The method of Para. AG, wherein the swine comprises gilts, barrows, boars, or combinations thereof.

[0121] Para. Al: The method of any one of Paras. U-AH, wherein the swine comprises gilts.

[0122] Para. AJ: The method of Para. AH, wherein the swine comprises barrows or boars.

[0123] Para. AK: The method of any one of Paras. U-AH, wherein the swine feed is a premix, a feed additive, a feed supplement, a compound feed, or a complete feed.

[0124] Para. AL: Use of a swine feed for improving feed conversion measured as feed to gain ratio of the swine compared to a control swine not fed the swine feed, wherein the swine feed comprises a nitrate compound, hydrates thereof, salts thereof, or combinations thereof, and wherein the daily feed intake amount of the nitrate compound, hydrates thereof, salts thereof, or combinations thereof is about 0.02% by weight to less than about 0.1% by weight based on total weight of the swine feed.

[0125] The present technology is also not to be limited in terms of the particular aspects described herein, which are intended as single illustrations. Many modifications and variations of this present technology can be made without departing from its spirit and scope, as will be apparent to those skilled in the art from the foregoing descriptions. Such modifications and variations are intended to fall within the scope of the appended claims. It is to be understood that this present technology is not limited to particular methods, reagents, compounds, or compositions, which can, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular aspects only, and is not intended to be limiting. Thus, it is intended that the specification be considered as exemplary only with the breadth, scope and spirit of the present technology indicated only by the appended claims, definitions therein and any equivalents thereof.

[0126] The aspects, illustratively described herein may suitably be practiced in the absence of any element or elements, limitation or limitations, not specifically disclosed herein. Thus, for example, the terms “comprising,” “including,” “containing,” etc. shall be read expansively and without limitations. Additionally, the terms and expressions employed herein have been used as terms of description and not of limitation, and there is no intention in the use of such terms and expressions of excluding any equivalents of the features shown and described or portions thereof, but it is recognized that various modifications are possible within the scope of the claimed technology. Additionally, the phrase “consisting essentially of’ will be understood to include those elements specifically recited and those additional elements that do not materially affect the basic and novel characteristics of the claimed technology. The phrase “consisting of’ excludes any element not specified.