Saccharomyces cerevisiae cell wall extract rich in beta-glucan for preventing or treating diseases associated with or caused by lawsonia intracellularis infection

Abstract

The present invention relates to a beta-glucan-rich Saccharomyces cerevisiae (# imgabs0 #) cell wall extract for use in the prevention or treatment of swine diseases associated with or caused by Lawsonia intracellularis (# imgabs1 #) infection, characterized in that the extract comprises beta-glucan and mannan, in which the beta-glucan is in the form of beta-1, 3-glucan and beta-1, 3-glucan, and the mannan is in the form of beta-glucan and mannan, and the mannan is in the form of beta-glucan and mannan. The mannan is present in the form of a mixture of 1, 6-glucan in a total amount of greater than or equal to 50 wt%, in particular 50-99 wt%, and wherein the mannan is present in a total amount of less than 5 wt%, in particular 1-5 wt%.

Description

Technical Field

[0001] The invention relates to the field of health, in particular to the field of animal health. The invention more particularly relates to a saccharomyces cerevisiae rich in β-glucan ( ) cell wall extracts, and prevention or treatment thereof with Lawsonia intracellularis ( ) infection-related or caused by pig diseases. Background Art

[0002] Lawsonia intracellularis is an obligate Gram-negative intracellular bacterium that is the cause of porcine ileitis, also known as proliferative enteropathy, one of the most common digestive diseases affecting grow-finish pigs worldwide.

[0003] The disease is characterized by the proliferation of immature epithelial cells in the crypts of the ileum (the terminal part of the small intestine), the large intestine, or both. Sections of infected tissue are characterized by thickened, red mucosa that resembles a "hospital" and is associated with intestinal damage. The thickening of the intestine eventually impedes normal intestinal function, impairing absorptive capacity and nutrient transport. Clinical manifestations of the disease include chronic weight loss, loss of appetite, diarrhea, and ultimately death.

[0004] The disease can manifest itself in acute or chronic form. The chronic form mainly affects pigs between 6 and 20 weeks of age and the symptoms are quite common: reduced growth performance, i.e. reduced daily weight gain, with or without diarrhoea. Therefore, the disease often goes undetected. The acute form is characterized by bloody diarrhoea and sudden death, affecting pigs between 4 and 12 months of age. In infected herds, the disease causes significant economic losses to livestock farmers due to higher technical output, higher drug costs and induced mortality.

[0005] Currently, there are a variety of vaccination strategies available for the prevention and treatment of ileitis. They generally involve administering the vaccine parenterally (i.e. by injection) to young pigs. However, this approach is not entirely satisfactory as it is relatively cumbersome for livestock producers.

[0006] Therefore, there is a real need to develop new methods for preventing and / or treating diseases associated with or caused by Lawsonia intracellularis infection, such as ileitis in animals, in particular in pigs. Summary of the invention

[0007] In the present invention, the inventors surprisingly found that a β-glucan-rich Saccharomyces cerevisiae cell wall extract significantly enhanced the immunity of pigs that had been exposed to Lawsonia intracellularis, thereby providing a method for preventing and / or treating infections caused by the bacteria and / or diseases associated with or caused by the bacteria, in particular ileitis.

[0008] More particularly, the inventors were able to demonstrate that the use of a beta-glucan-rich Saccharomyces cerevisiae cell wall extract according to the invention to treat pigs exposed to Lawsonia intracellularis both promoted weight gain in the pigs and reduced the incidence of infection in the herd.

[0009] Furthermore, unlike parenteral vaccination strategies, β-glucan-rich Saccharomyces cerevisiae cell wall extracts can be administered via the oral route, particularly in feed, and thus act more directly in the intestine where the pathogen is primarily present.

[0010] Therefore, the object of the present invention is to provide a β-glucan-rich Saccharomyces cerevisiae cell wall extract for preventing or treating diseases in pigs associated with or caused by Lawsonia intracellularis infection, characterized in that the extract comprises β-glucan and mannan,

[0011] wherein the β-glucan is present in a total amount greater than or equal to 50 wt %, in particular 50 wt % to 99 wt % in the form of a mixture of β-1,3-glucan and β-1,6-glucan; and

[0012] The mannan is present in a total amount of less than 5% by weight, in particular 1% to 5% by weight.

[0013] In certain embodiments, the disease is inflammatory bowel disease, particularly ileitis.

[0014] In certain embodiments, the total amount of β-glucan in the β-glucan-enriched Saccharomyces cerevisiae cell wall extract is 50%-90% by weight of the extract, such as 50%-80% by weight, or 50%-70% by weight, or even 50%-60% by weight of the extract.

[0015] In certain embodiments, the total amount of mannan in the β-glucan-enriched Saccharomyces cerevisiae cell wall extract is 2% to 4% by weight of the extract.

[0016] In certain embodiments, the amount of mannan in the β-glucan-enriched Saccharomyces cerevisiae cell wall extract is such that the ratio of β-glucan / mannan is 12-40 (weight / weight).

[0017] In certain embodiments, the amount of mannan in the β-glucan-enriched Saccharomyces cerevisiae cell wall extract is such that the ratio of β-glucan / mannan is 15-30 (w / w), in particular 18-22 (w / w).

[0018] In certain embodiments, the β-glucan-enriched Saccharomyces cerevisiae cell wall extract is characterized by a dry matter content greater than or equal to 94% by weight, in particular greater than or equal to 96% by weight.

[0019] In certain embodiments, the β-glucan-enriched Saccharomyces cerevisiae cell wall extract is characterized in that it further comprises a protein content of less than or equal to 10% by weight, and a glycogen content of less than or equal to 10% by weight.

[0020] In certain embodiments, the β-glucan-enriched Saccharomyces cerevisiae cell wall extract is characterized in that β-glucan and mannan are the only active ingredients of the β-glucan-enriched Saccharomyces cerevisiae cell wall extract.

[0021] In certain embodiments, the β-glucan-enriched Saccharomyces cerevisiae cell wall extract is characterized in that it is actually Safglucan® comprising β-glucan and mannan, wherein the β-glucan is present in the form of a mixture of β-1,3-glucan and β-1,6-glucan in a total amount of 52 wt%-60 wt%; the mannan is present in a total amount of 1 wt%-5 wt%; and wherein Safglucan® further comprises a protein content of less than or equal to 10 wt%, and a glycogen content of less than or equal to 10 wt%.

[0022] In a second aspect, the present invention relates to a composition comprising a β-glucan-rich cell wall extract of Saccharomyces cerevisiae and at least one bioactive agent for preventing infections in pigs associated with Lawsonia intracellularis bacteria, characterized in that the extract is as defined in the present patent specification.

[0023] In certain embodiments, the bioactive agent is selected from the group consisting of antibiotics, vaccines, probiotics, prebiotics, vitamins, minerals, trace elements, and mixtures thereof.

[0024] In a third aspect, the present invention relates to a pharmaceutical composition comprising a β-glucan-rich Saccharomyces cerevisiae cell wall extract and at least one physiologically acceptable excipient for preventing or treating infections in pigs associated with Lawsonia intracellularis bacteria, characterized in that the extract is as defined in the present description.

[0025] In a fourth aspect, the present invention relates to a feed for pigs, comprising a β-glucan-rich Saccharomyces cerevisiae cell wall extract for preventing diseases in pigs associated with or caused by Lawsonia intracellularis infection, characterized in that the extract is as defined in the present specification or is part of the composition defined in the present specification. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is the body weight of the animal during the experiment;

[0027] Figure 2 is the average weight gain during the trial period: black = control group, grey = treatment group. ** p<0.005, *** p<0.0001

[0028] Figure 3 Quantification of Lawsonia intracellularis in feces of two groups of pigs (control group: black bar graph, treatment group: gray bar graph). N=40 per group. P<0.0005*** DETAILED DESCRIPTION

[0029] The invention is explained in a more detailed and non-limiting manner in the following description.

[0030] Unless otherwise stated, all percentages relating to amounts are by weight.

[0031] As mentioned above, the present invention relates to a β-glucan-rich cell wall extract of Saccharomyces cerevisiae for use in preventing or treating diseases in animals (particularly pigs) associated with or caused by infection with Lawsonia intracellularis, characterized in that the extract comprises β-glucan and mannan,

[0032] wherein the β-glucan is present in a total amount greater than or equal to 50 wt %, in particular 50 wt % to 99 wt % in the form of a mixture of β-1,3-glucan and β-1,6-glucan; and

[0033] The mannan is present in a total amount of less than 5% by weight, in particular 1% to 5% by weight.

[0034] In certain specific embodiments, the animal to which the present invention is applied is an animal selected from farm animals and pets, particularly a pig or a horse.

[0035] Therefore, all extracts, compositions, pharmaceutical compositions and feeds forming the subject of the present invention and described hereinafter with reference to pigs, can likewise be applied to other animal species, in particular horses.

[0036] As used herein, the term "pig" refers broadly to species of the Suidae family.

[0037] As used herein, the term "horse" refers broadly to animals of the family Equine.

[0038] The term "disease associated with or caused by Lawsonia intracellularis infection" refers to a disease that is indirectly associated with ("associated with") or directly associated with ("caused by") Lawsonia intracellularis infection.

[0039] I-β-glucan-rich Saccharomyces cerevisiae cell wall extract

[0040] The beta-glucan in the extract according to the invention is obtained from Saccharomyces cerevisiae, more particularly from a strain of Saccharomyces cerevisiae. The prior art includes many known strains of Saccharomyces cerevisiae. They are widely used in the agri-food industry and play a role in many food manufacturing processes, especially in the manufacture of bread and fermented beverages.

[0041] The term "yeast strain" as used herein refers to a relatively homogeneous group of yeast cells obtained by culturing (or propagating) a starting strain. A yeast strain is obtained by cloning, and a clone refers to a group of yeast cells obtained from a single yeast cell. Saccharomyces cerevisiae strains can be cultured using any suitable method. Yeast culture methods are known in the art, and those skilled in the art know how to optimize their culture conditions according to the properties of each strain. Therefore, Saccharomyces cerevisiae can be obtained by culturing strains in appropriate culture media, such as described in the reference book Yeast Technology, 2nd edition (1991, G. Reed and TW Nagodawithana, published by Van Nostrand Reinhold, ISBN 0-442-31892-8).

[0042] The terms "yeast cell wall" and "yeast coat" are used interchangeably herein and refer to the insoluble part of the yeast cell, i.e. the cell wall and plasma membrane of the yeast. Traditionally, the yeast cell wall is obtained by a process comprising an autolysis or enzymatic hydrolysis step, mainly hydrolysis by proteases, followed by a separation step to separate the soluble part from the insoluble part, the separated insoluble part corresponding to the yeast cell wall. The insoluble part can then be further dried. The yeast cell wall is obtained in a preparation method that enables it to retain the structural polysaccharides of the cell wall, i.e. β-glucans and mannans, which are in the form of mannoproteins. Preparation methods for obtaining yeast cell walls are known in the art (see, for example, the reference book "Yeast Technology" 2nd edition, 1991, by G. Reed and TW Nogodawithana, published by VanNostrand Reinhold, New York, ISBN 0-442-31892-8).

[0043] The β-glucan-rich cell wall extract of Saccharomyces cerevisiae according to the present invention refers to a portion extracted (or separated) from the cell wall, mainly containing β-glucan. β-glucans derived from yeast cell walls are called "cell wall β-glucans". They are essentially glucose polymers, the glucose units in their backbone are linked by β-1,3 bonds, and their branches are linked by β-1,6 bonds. Yeast β-glucans are insoluble and have low viscosity. Those skilled in the art know how to extract β-glucans from yeast cell walls. Common methods include continuous heat extraction with alkali and acid (e.g. acetic acid), followed by washing with water to remove any soluble compounds in the cell wall and recover the insoluble material consisting of cell wall β-glucans.

[0044] The β-glucan-rich cell wall extract of Saccharomyces cerevisiae according to the present invention comprises a total amount of β-glucan greater than or equal to 50% by weight, in the form of a mixture of β-1,3-glucan and β-1,6-glucan. As used herein, the term "a total amount of β-glucan greater than or equal to 50% by weight" means that β-glucan accounts for at least half of the weight of the extract of the present invention. Therefore, the total amount of β-glucan present in the extract of the present invention may account for 50%-90% by weight of the extract, such as 50%-80% by weight of the extract, or 50%-70% by weight, or even 50%-60%.

[0045] In certain specific embodiments, the total amount of β-glucan present in the extract of the present invention is 50%-65% by weight of the extract, such as about 51%, about 52%, about 53%, about 54%, about 55%, about 56%, about 57%, about 58%, about 59%, about 60%, about 61%, about 62%, about 63%, about 64% or about 65%.

[0046] The β-glucan-rich cell wall extract of Saccharomyces cerevisiae according to the invention also contains less than 5% by weight of mannan in total. Mannans derived from yeast cell walls are called "cell wall mannans". They are yeast polysaccharides, mainly composed of mannose, more precisely, copolymers of neutral or acidic sugars (having 5 or 6 carbon atoms) linked together by glycosidic bonds and bound to proteins. In the cell wall mannans of Saccharomyces cerevisiae, mannose is present in the form of a main chain of α-(1,6)-linked mannose residues (50 or more), which is branched by short chains of α-(1,2)- and α-(1,3)-linked mannose. Those skilled in the art know how to extract mannans from yeast cell walls. A common method involves enzymatic digestion of yeast cell walls using a preparation of β-glucanase (e.g. the industrial preparation GLUCANEX™), followed by separation of the hydrolyzate by centrifugation and purification by ultrafiltration. Another method is based on thermochemical extraction.

[0047] As used herein, the term "less than 5% by weight of total amount of mannan" means that mannan accounts for at most 5% by weight of the extract of the present invention. Thus, the total amount of mannan present in the extract of the present invention may account for 0.5%-5% by weight of the extract, in particular 0.5%-1.5% by weight of the extract.

[0048] Preferably, the β-glucan-rich Saccharomyces cerevisiae cell wall extract of the present invention comprises β-glucan and mannan, wherein the β-glucan is present in a total amount of greater than or equal to 50% by weight in the form of a mixture of β-1,3-glucan and β-1,6-glucan; and the mannan is present in a total amount such that the ratio of β-glucan / mannan is 12-40 (weight / weight). In particular, in the extract of the present invention, the ratio of β-glucan / mannan may be 15-30 (weight / weight), and further particularly 18-22 (weight / weight).

[0049] In certain embodiments, the β-glucan-enriched Saccharomyces cerevisiae cell wall extract of the present invention further comprises a protein content of less than or equal to 10% by weight, and a glycogen content of less than or equal to 10% by weight.

[0050] In certain embodiments, the β-glucan-enriched Saccharomyces cerevisiae cell wall extract of the present invention comprises only β-glucan and mannan as active ingredients, wherein the β-glucan is present in a total amount greater than or equal to 50 wt% as a mixture of β-1,3-glucan and β-1,6-glucan; and the mannan is present in a total amount less than 5 wt%, such that the ratio of β-glucan / mannan is 12-40 (w / w), particularly 15-30 (w / w), and more particularly 18-22 (w / w).

[0051] In certain specific embodiments, the β-glucan-rich Saccharomyces cerevisiae cell wall extract of the present invention has a dry matter content of greater than or equal to 94% by weight, preferably greater than or equal to 96% by weight. A dry matter content of greater than or equal to 94% by weight, preferably 96% by weight, can better preserve the yeast shell, especially enhance bacterial stability and enhance stability to adverse reactions of enzyme sources or non-enzyme sources.

[0052] In certain specific embodiments, the Saccharomyces cerevisiae cell wall extract of the present invention is in the form of a powder.

[0053] In certain specific embodiments, the β-glucan-rich Saccharomyces cerevisiae cell wall extract of the present invention is Safglucan® produced by the applicant Lesaffre. Safglucan® contains only β-glucan and mannan as active ingredients, wherein β-glucan is present in a total amount of 52% by weight to 60% by weight in the form of a mixture of β-1,3-glucan and β-1,6-glucan; and mannan is present in a total amount of 1% by weight to 5% by weight. Safglucan® further contains a protein content of less than or equal to 10% by weight, and a glycogen content of less than or equal to 10% by weight.

[0054] After manufacturing, the β-glucan-rich yeast cell wall extract of the present invention can be packaged and / or stored under appropriate conditions before use, usually in a dry and cool place. The cell wall extract of the present invention has a shelf life of 2 years from the date of production under appropriate packaging.

[0055] II- Compositions comprising a cell wall extract of Saccharomyces cerevisiae rich in β-glucan

[0056] In certain embodiments, the β-glucan-enriched Saccharomyces cerevisiae cell wall extract described herein can be used alone, particularly in the absence of any other active substances.

[0057] In other embodiments, the β-glucan-rich Saccharomyces cerevisiae cell wall extract described herein is used in combination with at least one other bioactive agent. Thus, the present invention relates to a composition comprising a β-glucan-rich Saccharomyces cerevisiae cell wall extract as described herein in combination with at least one bioactive agent.

[0058] As used herein, the term "biologically active agent" refers to an agent that is beneficial to the health of an animal. It can be a veterinary active substance with a therapeutic or preventive effect. The biologically active agent can be, for example, selected from antibiotics, vaccines, probiotics or prebiotics, or mixtures thereof.

[0059] In certain embodiments, the bioactive agent is selected from an antibiotic, a vaccine, or a prebiotic.

[0060] In particular, it does not include probiotics, and especially does not include microbial pesticides such as Bacillus subtilis ( ) of the QST-713 strain.

[0061] By extension, the term "bioactive agent" also refers to substances which have a beneficial effect from a nutritional point of view, in particular nutritional substances, such as vitamins, minerals or trace elements, in particular those substances which are usually present in supplements, adjuvants or feed additives for animals.

[0062] Those skilled in the art know how to select appropriate components depending on the animal for which the composition is intended, in this case pigs, and how to determine appropriate amounts of these components in the composition.

[0063] The composition of the present invention may be in any form, such as powder, granules, gel or liquid form. Preferably, the composition according to the present invention is in solid form, preferably powder form.

[0064] The present invention also relates to a pharmaceutical composition comprising a β-glucan-rich Saccharomyces cerevisiae cell wall extract as described herein and at least one physiologically acceptable excipient for veterinary use. In the pharmaceutical composition, the extract may be present as the sole active ingredient. Alternatively, the pharmaceutical composition may further comprise at least one other biologically active agent, such as those listed above.

[0065] The pharmaceutical composition of the present invention may be classified as a veterinary pharmaceutical preparation and may be obtained by prescription or as an over-the-counter drug.

[0066] In the context of the present invention, the term "physiologically acceptable excipient for veterinary use" refers to any medium or additive that does not interfere with the efficacy of the biological activity of the active ingredient (in this case, the β-glucan-enriched cell wall extract) and is not unduly toxic to animals at the concentration at which it is administered.

[0067] The veterinary pharmaceutical composition of the present invention may be administered using any combination of dosages and routes of administration effective to achieve the desired prophylactic effect. Preferably, the pharmaceutical composition is administered by the oral route. One skilled in the art will recognize that the exact amount administered to the pig may vary depending on the weight of the animal and the effect of the intracellular Lawsonia on the treated animal.

[0068] III- Use of dried β-glucan-rich Saccharomyces cerevisiae cell wall extract

[0069] As mentioned above, L. intracellularis infections in pigs can lead to intestinal inflammation, particularly ileitis, which can cause diarrhea and, in some cases, sudden death. As a result of these infections, the animals’ feed conversion rate and weight gain are reduced.

[0070] The β-glucan-rich Saccharomyces cerevisiae cell wall extract described herein has been shown to significantly reduce symptoms associated with Lawsonia intracellularis infection.

[0071] Therefore, the present invention also relates to a β-glucan-rich Saccharomyces cerevisiae cell wall extract, which is used alone or in combination with at least one biologically active agent for preventing or treating Lawsonia intracellularis infection in pigs.

[0072] Therefore, the present invention also relates to a β-glucan-rich Saccharomyces cerevisiae cell wall extract, as described herein, for use alone or in combination with at least one bioactive agent for preventing or treating disease in pigs associated with or caused by Lawsonia intracellularis infection.

[0073] The disease associated with or caused by Lawsonia intracellularis may be an intestinal inflammation, in particular an intestinal inflammation selected from the group consisting of enteritis or ileitis.

[0074] The present invention also relates to a β-glucan-rich Saccharomyces cerevisiae cell wall extract, as described herein, for use alone or in combination with at least one bioactive agent for preventing or treating inflammatory intestinal diseases in pigs, particularly diseases associated with or caused by Lawsonia intracellularis infection, such as ileitis.

[0075] As used herein, the term "prevention" refers to any action intended to prevent or delay the onset of a disease, in particular to partially or completely reduce or inhibit the likelihood of a subject developing one or more symptoms associated with or caused by Lawsonia intracellularis infection (diarrhea, weight loss, intestinal wall thickening, etc.). The terms "prevention" and "prophylactic treatment" are equivalent and can be used interchangeably in the context of the present invention. Prevention can be directed to subjects who are prone to infection, preferably subjects who are prone to intestinal infection, but also to subjects who are not prone to such infection.

[0076] As used herein, the term "treatment" refers to any action intended to improve the medical condition of a subject suffering from a disease. Treatment may be intended to improve the patient's medical condition, i.e., to provide relief from the disease or some of its symptoms, or to eliminate the disease or some of its symptoms. Treatment may also have the effect of preventing or slowing the progression of a disease.

[0077] In certain embodiments of the invention, the extract or composition is intended for use in preventing disease in pigs associated with or caused by Lawsonia intracellularis.

[0078] In certain embodiments of the present invention, using a β-glucan-rich Saccharomyces cerevisiae cell wall extract alone or in combination with at least one bioactive agent to prevent diseases associated with or caused by Lawsonia intracellularis bacteria comprises blending the β-glucan-rich Saccharomyces cerevisiae cell wall extract with animal feed ingredients. The blending can be performed by any suitable method known in the art.

[0079] As used herein, the terms "animal feed," "animal feed ingredient," and "animal feed product" refer to any natural or processed organic material that is readily biodegradable and suitable for animal consumption. Examples of such organic materials range from newly harvested grains to pelleted feed materials, and include, for example, any compound, grain, nut, forage, silage, preparation, composition or mixture suitable or intended for ingestion by an animal. Animal feed materials may be in the form of pellets, liquids, slurries, or so-called "paste feeds."

[0080] The term "forage" refers to plant material (mainly leaves and stems of plants) for herbivorous animals. The term "silage" refers to fermented feed with a high moisture content suitable for use as feed for ruminants. Preparations, compositions and blends, such as commercial preparations, compositions and blends, can be in any suitable form, such as concentrates, premixes, supplements, total mixed rations (TMR), etc. Animal feed can contain cereals (such as corn, wheat, barley, rye, rice, sorghum, millet, or a combination thereof), forage, silage, pulses (such as soybeans), spent grains, animal products, etc. Spend grains are mainly derived from the processing of corn, wheat, barley, rye, rice, sorghum, millet, or a combination thereof. Spend grains are mainly generated in industrial processes such as brewing and distilling, which are intended to produce potable alcohol (such as whiskey, vodka or gin) or biofuels. Spend grains are generated from malt, which in turn is derived from barley. In addition to barley, other grains are sometimes used for brewing, such as sorghum, especially in Africa. The grains from bioethanol production come from corn or wheat. The wet grains are dried to produce dry grains, which are mainly used as animal feed.

[0081] The cell wall extract of Saccharomyces cerevisiae enriched in β-glucan as described herein, used alone or in combination with at least one biologically active agent, can be added to animal feed in an amount of about 0.02% to about 0.05% of the total weight of the feed material (which corresponds to an amount of about 200 grams to about 500 grams per ton of feed material), provided that current applicable regulations are complied with. For example, in certain embodiments, the cell wall extract of Saccharomyces cerevisiae enriched in β-glucan as described herein, used alone or in combination with at least one biologically active agent, is added to animal feed material in an amount of about 0.02% to about 0.05% of the total weight of the feed material (which corresponds to an amount of about 200 to about 500 grams per ton of feed material), for example, in an amount of about 0.02% to about 0.05% by weight of the feed material (which corresponds to about 200 to about 500 grams per ton of feed material).

[0082] The extract or composition of the invention may be administered throughout the duration of the infection or throughout the risk of infection. In particular, it may be administered continuously with the feed with the aim of preventing: diseases associated with or caused by Lawsonia intracellularis bacteria; and / or Lawsonia intracellularis infection.

[0083] Unless otherwise defined, all technical and scientific terms used in the specification have the same meaning / meaning as commonly understood by those skilled in the art, ie, experts in the field to which the present invention belongs.

[0084] Example

[0085] The following examples describe certain embodiments of the present invention. However, it should be understood that these examples and drawings are presented for illustrative purposes only and are not intended to limit the scope of the present invention in any way.

[0086] Materials and methods

[0087] 160 piglets (Danbred x Duroc cross) were obtained from a commercial breeding farm and placed in a finishing / finishing unit in the presence of Lawsonia intracellularis bacteria. On arrival at the farm, the piglets were individually weighed and ear-tagged. The animals were then divided into two groups (1 control group and 1 treatment group) of 80 pigs each. The animals were then divided into groups of 10 pigs each. The control group received a standard diet. The treatment group received a normal diet to which a beta-glucan product (250 ppm) was added throughout the trial. Animals from both groups were weighed on days 63, 81, and 97; at the same time, their feces were collected to detect the presence of Lawsonia intracellularis by quantitative qPCR.

[0088] result

[0089] The results showed that after 97 days of treatment, the average weight of each animal in the treatment group increased by about 5 kg ( Figure 1 and Figure 2 ).

[0090] The presence of Lawsonia intracellularis in feces was significantly reduced ( Figure 3 ).

Claims

1. A β-glucan-rich Saccharomyces cerevisiae cell wall extract for preventing or treating diseases in pigs associated with or caused by Lawsonia intracellularis infection, characterized in that The extract contains β-glucan and mannan, wherein the β-glucan is present in a mixture of β-1,3-glucan and β-1,6-glucan in a total amount greater than or equal to 50% by weight, in particular 50% to 99% by weight; and The mannan is present in a total amount of less than 5% by weight, in particular 1% to 5% by weight.

2. The β-glucan-rich Saccharomyces cerevisiae cell wall extract for use in preventing or treating a disease in pigs associated with or caused by Lawsonia intracellularis infection according to claim 1, wherein the disease is inflammatory bowel disease, particularly ileitis.

3. A β-glucan-rich Saccharomyces cerevisiae cell wall extract for use in preventing or treating diseases in pigs associated with or caused by Lawsonia intracellularis infection according to claim 1 or 2, wherein the total amount of β-glucan present in the β-glucan-rich Saccharomyces cerevisiae cell wall extract is 50%-90% by weight of the extract, such as 50%-80% by weight of the extract, or 50%-70% by weight, or even 50%-60% by weight of the extract.

4. A β-glucan-rich Saccharomyces cerevisiae cell wall extract for use in preventing or treating diseases in pigs associated with or caused by Lawsonia intracellularis infection according to any one of claims 1 to 3, wherein the total amount of mannan present in the β-glucan-rich Saccharomyces cerevisiae cell wall extract is 2%-4% by weight of the extract.

5. The β-glucan-rich Saccharomyces cerevisiae cell wall extract for use in preventing or treating diseases in pigs associated with or caused by Lawsonia intracellularis infection according to any one of claims 1 to 4, wherein the amount of mannan in the β-glucan-rich Saccharomyces cerevisiae cell wall extract is such that the ratio of β-glucan / mannan is 12-40 (weight / weight).

6. A β-glucan-rich Saccharomyces cerevisiae cell wall extract for use in preventing or treating diseases in pigs associated with or caused by Lawsonia intracellularis infection according to any one of claims 1 to 5, wherein the amount of mannan in the β-glucan-rich Saccharomyces cerevisiae cell wall extract is such that the ratio of β-glucan / mannan is 15-30 (w / w), in particular 18-22 (w / w).

7. The β-glucan-rich cell wall extract of Saccharomyces cerevisiae for preventing or treating diseases in pigs associated with or caused by Lawsonia intracellularis infection according to any one of claims 1 to 6, characterized in that Its dry matter content is greater than or equal to 94% by weight, in particular greater than or equal to 96% by weight.

8. The β-glucan-rich cell wall extract of Saccharomyces cerevisiae for preventing or treating diseases in pigs associated with or caused by Lawsonia intracellularis infection according to any one of claims 1 to 7, characterized in that It contains a protein content of less than or equal to 10% by weight and a glycogen content of less than or equal to 10% by weight.

9. The β-glucan-rich cell wall extract of Saccharomyces cerevisiae for preventing or treating diseases in pigs associated with or caused by Lawsonia intracellularis infection according to any one of claims 1 to 8, characterized in that The β-glucan and the mannan are the only active ingredients in the β-glucan-rich Saccharomyces cerevisiae cell wall extract.

10. The β-glucan-rich Saccharomyces cerevisiae cell wall extract for prevention or treatment according to claim 9, characterized in that: The extract is Safglucan® containing β-glucan and mannan, wherein the β-glucan is present in a total amount of 52 wt% to 60 wt% in the form of a mixture of β-1,3-glucan and β-1,6-glucan; and the mannan is present in a total amount of 1 wt% to 5 wt%; and, Wherein the Safglucan® further comprises a protein content of less than or equal to 10 wt %, and a glycogen content of less than or equal to 10 wt %.

11. A composition comprising a β-glucan-rich cell wall extract of Saccharomyces cerevisiae and at least one bioactive agent for preventing infections in pigs associated with Lawsonia intracellularis bacteria, characterized in that The extract is as defined in claims 1-10.

12. The composition according to claim 11, wherein the bioactive agent is selected from the group consisting of antibiotics, vaccines, probiotics, prebiotics, vitamins, minerals, trace elements and mixtures thereof.

13. A pharmaceutical composition comprising a β-glucan-rich cell wall extract of Saccharomyces cerevisiae and at least one physiologically acceptable excipient for preventing or treating infections in pigs associated with Lawsonia intracellularis bacteria, characterized in that The extract is as defined in claims 1-10.

14. A pig feed comprising a β-glucan-rich Saccharomyces cerevisiae cell wall extract for preventing diseases in pigs associated with or caused by Lawsonia intracellularis infection, characterized in that: The extract is as defined in claims 1 to 9 or is part of a composition as defined in claims 11 and 12.

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