TW201532518A - Packaged rodenticidal bait - Google Patents

Abstract

A packaged rodenticidal bait comprises a soft bait composition enrobed in a perforated thermoplastic film, wherein the soft bait composition comprises a blend of at least one edible fat, at least one particulate food component and at least one rodenticidally-active substance. Preferably, the thermoplastic film comprises one or more polyolefins. The perforated film used in the manufacture of the packaged bait according to the invention does not absorb fat, unlike conventionally-used paper sachets. The packaged bait composition of the invention is palatable to rodents such that rodents may take a lethal dose of a rodenticide from the bait in a single sitting.

Description

Packaging rodent

The present invention relates to packaging rodent control baits. More specifically, it relates to packaged soft bait compositions for controlling rodents, particularly rats and mice.

The bait containing the rodent control active is usually formulated into a soft paste composition. The soft bait compositions typically comprise a blend of particulate food components (e.g., cereal flour) with fat (which acts as a binder for the particulate component) and a blend of rodent foods, the blend containing one or A variety of rodenticide active substances. The use of fat in the composition provides a blend that can be divided into small amounts and molded or shaped.

Typically, the soft bait composition is packaged in a paper sachet for a single feed application. The paper sachet retains the bait therein and is uncontaminated until consumed by the rodent, and allows the bait to be stored and placed in position for professional users and general public users to control the rodent in an easy to use manner. The walls of the sachets allow aroma from the composition of the composition to pass to attract the rodent to the bait.

The paper sachet is an absorbent and thus absorbs fat from the soft bait composition. Absorption of fat is exacerbated when the fat component of the soft bait composition softens as it begins to melt during warming environmental conditions. The absorption of fat by the paper sachet has the effect of carrying fat onto the surface of the bait, which unfortunately detracts from the palatability of the bait to the target rodent. In addition, many of the rodenticide actives used in rodent controlled baits are lipophilic. Therefore, in these cases, the fat absorbed into the paper sachet contains a fat-soluble rodent-killing active substance. Carrying fat and fat-soluble actives to the surface of the bait in this manner reduces palatability and significantly deviates from the concept of making a rodent palatable blend. In addition, it contains absorbed fat and The paper-based sachet of the fat-soluble rodenticide increases the risk of the rat bait and does not self-feed the lethal dose of the rodenticide.

It is an object of the present invention to provide a packaged bait that overcomes the problems associated with conventional paper pods containing soft bait compositions.

The present invention provides a packaged rodent bait comprising a non-particulate soft bait composition coated in a perforated thermoplastic film, wherein the soft bait composition comprises at least one edible fat, at least one particulate food component, and at least one rodenticide active substance Blend.

As used herein, the term "coating" means that the soft bait composition is tightly wrapped in a perforated thermoplastic film so as not to be loosely contained therein. Preferably, the soft bait composition is tightly enclosed in a perforated thermoplastic film.

The expression "soft bait composition" means a bait composition that is formulated to have a pasty consistency (ie, easily create contact or pressure and is deformable). Preferably, the soft bait composition is malleable.

The packaged bait of the present invention overcomes the problems associated with the bait packaged in a paper sachet because it does not undergo the absorption of fat by the perforated thermoplastic film and therefore does not transport the fat to the surface, but it still allows the fragrance to escape. The film is acted as a rodent attractant.

In accordance with the present invention, the soft bait composition is coated in a perforated thermoplastic film. Preferably, the thermoplastic film comprises one or more polyolefins typically selected from the group consisting of polyethylene, polypropylene, and copolymers of ethylene and polypropylene.

The thermoplastic film can be a single layer film or a multilayer film. Multilayer polyolefin films are well known in the art and typically include a "skin" layer on each side of the "core" layer and the "core" layer. The "core" layer may comprise a polymer blend, the main component of which is a homopolymer or copolymer of ethylene and the minor component is a homopolymer or copolymer of butene. The "skin" layer typically comprises a homopolymer of ethylene or propylene or a copolymer of ethylene and propylene. Preferably, the membrane is either a single layer or more The film is oriented such that it can be heat shrunk in at least one direction. The use of a shrink film allows the film surrounding the bait composition to be shrunk to tightly enclose or enclose the bait composition within the film.

Thermoplastic films are commercially available in a variety of film thicknesses. Typical thicknesses range from 13 μm to 25 μm. It has been found that a packaged bait made using a perforated polyolefin film having a film thickness of 19 μm has good rodent palatability characteristics. A film having a thickness of 25 μm is acceptable, but has a lower rat palatability than a film having a thickness of 19 μm.

The thermoplastic film used to make the packaged rodent bait of the present invention is a perforated film. Pre-perforated films are well known in the art. Perforation in the membrane allows the aroma from the bait composition to escape to act as a target rodent food, and thus increase the palatability of the bait. However, the pore size is too small to allow the bait composition or its components to escape. The term "perforation" means a plurality of deliberately created apertures in a film. The perforations are preferably provided in a uniform manner in the film forming the wall of the package bait, i.e., each perforation is substantially equally spaced from its adjacent aperture to optimize the escape of the aroma from the package bait. Typically, the perforated thermoplastic film contains from 100 to 300 perforations per square centimeter, preferably from 150 to 250 perforations per square decimeter. It has been found that the use of a multilayer coextruded polyolefin shrink film having a uniform perforation of about 200 perforations per square centimeter enables the manufacture of packages having better properties in allowing aromatic escape and thus ensuring good rodent palatability. bait. The perforated thermoplastic film used in the present invention will have good abrasion resistance and tear resistance and good resistance to hot and fighting environment conditions. These perforated thermoplastic films are readily available on the market.

A soft bait composition for making a package bait comprises a blend of at least one edible fat, at least one particulate food component, and at least one rodenticide active.

The edible fat can be animal fat or vegetable fat or can be a combination of animal and vegetable fat. According to an embodiment, the edible fat may not be completely liquid at a temperature of 35 °C. The expression "not completely liquid" means that the edible fat includes solid fat crystals as well as any liquid oil. Thus, according to this embodiment, the edible fat is solid at normal room temperature (20 ° C) but not completely melted at a temperature of 35 ° C. Examples of vegetable fats that meet this preferred requirement Refined palm oil, a rodent that is especially delicious.

The soft bait composition which is itself non-particulate contains at least one particulate food component. Preferably, the particulate food component comprises a vegetable flour which may be a cereal flour, a non-cereal flour or a mixture of both cereal and non-cereal flour. Examples of cereal flours include oat flour, wheat flour, rice flour, and corn flour. Examples of non-cereal flours include potato flour, peanut flour, and soy flour. A mixture of any two or more of such powders may be used in the granular food component of the bait.

The particulate food component of the bait may also include one or more whole grains, nuts or seeds, ground grains, nuts or seeds or ground grains, nuts or seeds or any mixture of such materials. Preferably, the particulate food component will contain one or more of the following: needle oat flour, cut wheat, crushed corn, canary grass seeds, poppy seeds, sesame seeds, and sunflower seeds.

The soft bait composition used to make the present invention is formulated to have a pasty consistency. Typically, it comprises a mixture of a fat and granular food component in a paste form. The term "paste" as used herein means a softly viscous material that can be molded or formed into a dispersion comprising fine particulate solids in fat. It will be apparent to those skilled in the art that the weight ratio of edible fat to granular food composition for use in a soft bait composition will result in a composition having a pasty consistency, i.e., having a deformable character. Excessive fat or oil at ambient temperature will result in a semi-liquid composition, while fat or oil deficiency will result in a composition that is too hard under pressure and thus produces a composition that is not pasty consistency. Typically, the amount of edible fat in the soft bait composition will range from 5% to 30% by weight, based on the total weight of the composition. Preferably, the soft bait composition comprises at least 7.5% by weight, more preferably at least 10% by weight, based on the total weight of the composition, of edible fat. Preferably, the soft bait composition comprises no more than 25% by weight, more preferably no more than 20% by weight and most preferably no more than 18% by weight of edible fat based on the total weight of the composition.

The soft bait composition of the present invention contains at least one rodenticidal active. The rodenticide active may be an anticoagulant rodenticide, a non-anticoagulant rodenticide or a natural or synthetic toxicant. Examples of suitable anticoagulant rodenticides include difenacoum, flocoumafen, bromine Brodifacoum, bromodiolone, diphacinone, difethialone, warfarin, warfarin sodium, coumatetralyl, chlorophacinone ), coumachlor, coumafuryl and pindone. Examples of non-anticoagulant rodenticides include vitamin D, such as cholecalciferol (vitamin D3), ergosterol (vitamin D2), and norbormide. Other rodenticides useful in the present invention include natural poisons such as strychnine and scallopin; and synthetic poisons such as metal phosphides (such as zinc phosphide), sodium monofluoroacetate and metal cyanide Compounds (such as sodium cyanide) and alpha-chloralose.

Micro-encapsulated forms of rodent actives can also be used in the compositions of the invention.

According to a preferred embodiment, the soft bait composition of the present invention contains a non-anticoagulant rodenticide and is more preferred as a cholecalciferol. Cholecalciferol has been found to be sufficiently toxic to rats and mice and is effective against anticoagulant resistant rodents. Typically, the anticoagulant rodenticide will range from 0.001% to 0.05% by weight, preferably from 0.001% to 0.025% by weight, and more preferably from 0.0025% to 0.025% by weight, based on the total weight of the bait composition. The amount to use. If the bait contains vitamin D as a rodenticide active, this will typically be used in an amount of from 250 to 10,000 ppm (0.025 to 1.0% by weight based on the total weight of the bait). Of course, the actual amount used will depend on the identity of the rodent control active used and the target pest.

The soft bait compositions of the present invention may also advantageously contain one or more components such as sweeteners, vegetable oils, other food ingredients, pigments or dyes, flavoring agents, preservatives, antioxidants, and odor inhibitors. These other components are well known to those skilled in the art.

Preferably, the soft bait composition contains a sweetener. Typically, the sweetener is sucrose, preferably powdered sugar.

While palm oil and powdered sugar in soft bait compositions provide a very attractive taste to rodents, it may be further desirable to include one or more other agents that provide additional flavor and/or aroma to the soft bait composition to further increase the composition. Delicious.

In the field of rodenticides, usually one or more substances that act as human inhibitors quality. Such materials are usually provided with a taste and/or aroma that is countered by humans. These materials are typically bitter substances that impart an unpleasant taste to the bait for humans to notice. An example of such a odorant is denatonium benzoate. The inhibitor may be included in a total weight of typically about 0.001% by weight based on the total weight of the soft bait composition.

The soft bait composition will typically be colored by a colorant such as a dye or pigment to aid in the identification. Typically, the colorant will be present in an amount of about 0.002% by weight, based on the total weight of the composition.

The invention is also directed to a method of making a packaged rodent bait as described herein. The method comprises the steps of: (i) providing a soft bait composition on a perforated thermoplastic film; (ii) folding the perforated thermoplastic film to overlie the upper portion of the film over the lower portion of the film, and placing the soft bait composition in the folded Between the upper and lower portions of the membrane; and (iii) heat sealing the upper portion of the membrane to the lower portion of the membrane, wherein the upper portion is contacted with the lower portion to coat the soft bait composition in the membrane; typically, a packaging rodent bait is manufactured Used as a single feed application. Thus, for ease of use, the perforated thermoplastic film can be cut into a plurality of sizes such that the package bait is about 6 cm x 7 cm. The packaged bait is sized to accommodate sufficient bait composition that is not only formulated to achieve optimal palatability but also to deliver a lethal dose of rodent active to the rodent at one time.

Instance

1. A packaged rodent bait of the present invention is produced using a 5-layer coextruded polyolefin shrink film pre-perforated at a perforation density of 200 parts per square centimeter.

A soft bait composition having the formulation shown in the table below was prepared according to a conventional method.

100 g of the soft bait composition was placed on a 6 cm x 14 cm pre-perforated polyolefin film. The film is longitudinally folded over the bait composition and the top and bottom of the film each have three free edges overlapping. The overlapping tops and bottoms of the film are heat sealed together to make a package bait, wherein the bait composition is coated in a polyolefin film.

2. According to the present invention, a packaged bait prepared according to the above procedure is used in a field test as set forth below. For comparison, a conventional paper pouch containing a soft bait composition having the formulation shown in the above table was prepared and used in a field trial.

According to standard procedures, suitable test sites each having a mouse ( Mus domesticus) identified infection are selected and the feeding position of the mouse in operation is identified. The follow-up activities of the mice were measured 4 days before each test (before the census) and 4 days after the test (after the census). Non-toxic baits were used for pre-test census and post-test census periods, and toxic baits were used as described above for the 21-day trial period itself. The bait intake of the mice was periodically measured during these periods. In one test, the bait composition described above and packaged in a paper sachet was used. In another test, the bait composition coated in the pre-perforated polyolefin film as described above was used as set forth above.

For the test using the paper sachet type bait composition, the tracking score indicated that the mouse population was not reduced and the bait intake was low. From the tracking score and the bait intake measurement, 0% control was achieved during the test period using the bait composition packaged in the paper sachet.

For the test using the bait composition coated in the polyolefin film, the tracking score was 21 Significantly reduced during the day test period. During the same period of time, the intake was reduced from more than 300 g (in the pre-test census period) to about 15 g on the 21st day. Self-tracking scores and census uptake measurements calculated that 92% control was achieved during the test period using the bait composition coated in the polyolefin film.

The results of these tests indicated that the mice in the field trial found that the paper capsule composition was not attractive, while the composition coated with the polyolefin film was highly palatable to mice.

3. A bait composition coated with a polyolefin film prepared as described in 1. above and a conventional paper sachet containing the soft bait composition having the formulation shown in the above table as set forth in 2. The heat treatment was carried out at a temperature of 54 ° C for 24 hours. After this heat treatment, the bait composition coated with the polyolefin film and the paper sachet were cooled to ambient temperature and each used as a test bait in the following test procedure.

test program

Test baits and alternative controls (without active substance) were provided to each of the five male Wistar rats. An alternative control used in the test was the LabDiet (registered trademark) EUROdent diet 22% 5LFS from PMI Nutrition International. The ingredients of this meal are:

The total test bait of all 5 animals and the control diet were summed and the palatability ratio of each test bait was calculated as follows:

Therefore, a palatability ratio greater than 1.0 indicates that the test bait is more positive for the rat than the control diet. A delicious, and palatability ratio of 1.0 indicates that the test bait is as tasty as the control diet.

The palatability ratio of the heat-treated package bait of the present invention was 4.51. In comparison to this, the palatability ratio of the heat treated paper pod containing the bait formulation shown in the table was 3.51. The results of this test can be explained by the fact that conventional paper sachets absorb the fat released from the bait formulation during heat treatment and the fat absorbed into the paper sachet reduces the palatability of the package bait. Although the difference between these palatability ratios is not significant, these results indicate a trend that is expected to be reflected in the field.

Claims (19)

A packaged rodent bait comprising a non-particulate soft bait composition coated in a perforated thermoplastic film, wherein the soft bait composition comprises at least one edible fat, at least one particulate food component, and at least one rodenticide active substance Blend. The packaged rodent of claim 1 wherein the perforated thermoplastic film comprises one or more polyolefins. A packaged rodent bait according to claim 2, wherein the perforated thermoplastic film comprises a polyolefin selected from the group consisting of polyethylene, polypropylene, and a copolymer of ethylene and propylene. A packaged rodent bait according to any one of claims 1 to 3, wherein the thermoplastic film is a single layer film. A packaged rodent bait according to any one of claims 1 to 3, wherein the thermoplastic film is a multilayer film. A packaged rodent bait according to any one of claims 1 to 3, wherein the thermoplastic film is a shrink film. A packaged rodent bait according to any one of claims 1 to 3, wherein the perforated thermoplastic film contains from 100 to 300 perforations per square decimeter. The packaged rodent of claim 7, wherein the perforated thermoplastic film contains from 150 to 250 perforations per square centimeter. A packaged rodent bait according to any one of claims 1 to 3, wherein the thermoplastic film has a thickness of from 15 μm to 25 μm. A packaged rodent bait according to claim 9, wherein the thermoplastic film has a thickness of from 18 μm to 20 μm. A packaged rodent bait according to any one of claims 1 to 3, wherein the soft bait composition contains a fat which is not completely liquid at a temperature of 35 °C. A packaged rodent bait according to any one of claims 1 to 3, wherein the fat is tallow Fat, vegetable fat or a mixture thereof. The packaged rodent of claim 12, wherein the fat is refined palm oil. The packaged rodent bait of any one of claims 1 to 3, wherein the soft bait composition contains at least one particulate food component which is a vegetable powder selected from the group consisting of cereal flour and non-cereal flour. The packaged rodent of claim 14, wherein the plant powder is selected from the group consisting of oat flour, wheat flour, rice flour, corn flour, potato flour, peanut flour, and soy flour, and a mixture of two or more of the powders. . The packaged rodent bait of any one of claims 1 to 3, wherein the soft bait composition contains one or more whole grains or seeds, ground grains or seeds, cut or comminuted grains or seeds, and a mixture of any of the materials. The packaged rodent of claim 16, wherein the soft bait composition comprises one or more of the following: needle oat flour, cut wheat, crushed corn, canary grass seed, poppy seed, sesame seed, and sunflower seed . The packaged rodent bait according to any one of claims 1 to 3, wherein the rodenticide active substance is selected from the group consisting of difenacoum, brodifacoum, flocoumafen, bromadiolone ( Bromodiolone), difethialone, warfarin, coumatetralyl, chlorophacinone, diphacinone, coumachlor, coumafuryl ), pindone, ergosterol, cholecalciferol, norbormide, alpha chloralose, strychnine, sodium monofluoroacetate and sodium cyanide. A method of manufacturing a packaged rodent bait according to any one of claims 1 to 18, comprising the steps of: (i) providing a soft bait composition on the perforated thermoplastic film; and (ii) folding the perforated thermoplastic film to Having the upper portion of the film over the lower portion of the film And (iii) thermally sealing the upper portion of the film to the lower portion of the film, wherein the upper portion is The lower contact is to coat the soft bait composition in the film.