ITMI20110564A1 - RHODENTICIDAL LURE TRACER - Google Patents

Description

DESCRIPTION OF INDUSTRIAL INVENTION

Technical field

The present invention originates in the sector of products and formulations for pest control and / or agricultural use and refers to a rodenticide bait containing luminescent dyes.

The present invention originates in the sector of baits with rodenticide activity. These are edible compositions that have a luring component for rodents, particularly mice and rats, and a rodenticidal component.

Specifically, the present invention relates to a rodenticide bait comprising one or more active ingredients with an acute or chronic rodenticidal action and a priming agent containing luminescent dyes.

In particular, the invention relates to a rodenticide bait comprising one or more active ingredients with an acute or chronic rodenticide action and a priming agent containing fluorescent, fluorescent dyes or their mixtures.

State of the art

Rodents are grouped into about 130 species in the world. Mice and rats belong to the muridae family. In particular, the species present in urban environments include: Mus musculus, Rattus rattus and Rattus norvegicus. Rodents thrive in even critical environmental conditions and reproduce very quickly, for example, they live at temperatures between -40 ° C and 60 ° C, they survive electric shock (e.g. at 200 V they survive up to about a minute) and strong radiation.

WHO (World Health Organization) estimates that the ratio of rodents to humans has grown from 1: 1 in 1967 to 4: 1 in 1987.

The control of the infesting murine population has assumed an increasingly important role precisely in urban centers where adequate sanitary standards must be guaranteed.

The problem of murine infestations is particularly felt since rats and mice not only lead a parasitic life that causes a depletion of available food resources but are also carriers of diseases harmful to humans or pets. These diseases can be transmitted by murine species directly through manure on food or indirectly through ectoparasitic fleas that can lead to serious diseases such as plague, typhus, salmonella, rabies, yellow fever, leptospirosis.

To cope with this situation, disinfestation systems have been developed that make use of the use of physical, electronic and chemical means.

Physical means include mechanical traps, adhesives and ultrasounds.

Mechanical traps have a relative importance and are used above all for a census of species and number of presences. It is suggested the distribution of a fair number on the transit routes, triggering them with different food substances.

Adhesives are adhesive substances that can be useful in case of non-massive infestations and where the use of chemical rodenticides is not recommended. The high ambient temperatures and the dustiness of the premises are the main drawbacks that reduce its effectiveness.

As far as the use of ultrasound is concerned, a rapid habituation of murine species was found to the typical frequencies used, those higher than 20 MHz, not perceptible to the human ear. In addition, noise disturbance has been found to cause more discomfort to pets than to rodents.

The genetic control of mice also represents an innovative field of research since the scholars Marsh and Howard saw the possibility of altering the genetic heritage of these animals. After the first and encouraging successes, however, it has been realized that natural selection eliminates deleterious genes quite quickly. This is therefore a field of research still in the very early stages with the related problems to be solved.

Available chemical means can be divided into the following classes:

a) repellents,

b) attractants,

c) chemosterilizers,

d) rodenticides.

The use of repellents is still in the experimental phase despite the scientific research started several decades ago. Actidione, trinitrobenzene-aniline, thiouram disulfide, hexachlorophene and various dithiocarbamates proved to be of the many particularly active substances tested. It was evident, however, that the repellents alone cannot solve the problem also because the rodents removed from a certain area take refuge in another.

The attractants are compounds with exactly the opposite action to that of the above repellents. They are in fact used to attract animals to specific places overcoming the natural and innate distrust. There are generally two groups of substances most widely used: pheromones, specific natural odors, and compounds not related to hormonal natural odors. Among the non-pheromonic principles used there are: various types of vegetable oils, sugar, molasses, glycerin, salt, sodium glutamate, etc. In addition to pheromones, other volatile substances have shown a good attractive efficacy and among these there is the effective carbon disulfide in increasing the consumption of bait.

Among the chemo sterilizers it is known the use of triethylenmelamine which, although providing the best results, has the limit of not being able to sterilize males and females at the same time. However, sterilizing chemo has the limit of not being effective in a single administration. Although it is capable of eliminating up to 85% of the treated mouse population and inducing permanent sterility in surviving adult males, it is not active on young prepubertal females, on females of Rattus norvegicus and on both sexes. of all ages of Mus musculus.

In addition to these limitations, chemosterilizers cannot be used where there is a problem of massive infestation or where even the presence of a single Mus musculus cannot be tolerated.

Among the chemical methods, rodenticide baits represent the most important one. Rodenticide baits are products or formulations with engaging enticing effect; these in fact attract the targeted animal to feed on it. The addition of a poison makes it a poisoned bait. The greater the luring effect and the liking of the bait, the greater the possibility of a good result.

Commonly used rodenticides can be divided into two categories: acute or single dose rodenticides and chronic or multiple dose rodenticides. Natural poisons and synthetic poisons belong to the first category: natural poisons include scilliroside and strychnine, while synthetic poisons include crimidine, sodium fluoroacetate and fluoroacetamide, zinc phosphide, norbormide, thallium sulphate and the antu. Although acute rodenticides are not as effective as chronic ones (anticoagulants), they find valid use in emergency situations, when the killing of the murine population must be achieved in the shortest possible time. However, they are accompanied by many disadvantages among which the extreme danger for man and for the non-target species and the increase in mistrust on the part of rodents stand out.

The most effective and most used tool for the fight against weeds is the poisoned bait with chronic rodenticide action based on anticoagulant active ingredients. Anticoagulants can be divided, according to the mode of action, into multiple dose (or first generation) and single dose (or second generation) anticoagulants. The already known warfarin, coumachlor, coumatetralyl, coumafuril, pivaldione, difacinone and chlorofacinone belong to the first series; in the second series, bromadiolone, difenacoum, brodifacoum, difethialone and flocoumafen.

These baits take advantage of a mode of action that does not appear for 2-3 days after ingestion, regardless of the amount of food ingested.

In formulating a bait, both the behavioral habits and the dietary habits of the species must be taken into account.

The formulations currently on the market are various and so for example an active ingredient can be presented in the form of cereals, floured and flaked baits, paste baits, pellets, paraffin baits, track powder or tracers, fresh gel bait or greasy bait. or concentrated liquid.

To increase the attractiveness and palatability of the bait, particular aromas, fruit, animal proteins, vegetable oils and sugar are used. Finally, other substances such as preservatives, dyes and bitters can be added to the bait.

Cereals form the basis of rodent nutrition in numerous environmental contexts, and their use is undoubtedly a valid priming system. Those most suitable in the fight against rodenticides are devoid of integuments in order to favor the complete absorption of the active principle. The use of kernels covered by the integuments is in fact to be avoided, since the latter, covering the seed, also prevent its complete imbibition by the active principle, ensuring that the rodent, once the integuments have been discarded, seed foods without taking the active ingredient.

Whole or floured cereals are often enclosed in sachets of paper or transpiring plastic material in order to favor an optimal conservation of the product, an easy replacement of the bait and a lower risk of dispersion in the environment. The practice of enveloping also allows the presence of rodents to be detected since the rat has to break the bag to feed on the bait and also allows greater preservability and duration of the bait in the environment. However, the use of rodenticide baits in the form of cereals is not free from drawbacks such as poor uniformity in the distribution of the active ingredient and the possibility of finding insect infestations. Furthermore, given that it is very easy for rodents to move grains or flakes and accumulate them in areas even several meters away from the poisoning station, it is possible that serious risks of contamination arise when working in the presence of foodstuffs.

The flaked and floured bait is composed of a mixture of flaked cereals and crushed and floured grains and other highly palatable food components. The components used are: flaked wheat and oats enriched with enticing substances, sugar, whole wheat, sunflower seeds. The presence of different components increases the likelihood that the target animal will identify one of them which is particularly appreciated and therefore start consumption.

The pellets are produced in a similar way to feeds for zootechnical use: through special production lines, the pulverized cereals and the active principle are mixed together with thickening substances and proteins of animal and vegetable origin and drawn. The palatability of the baits thus obtained is generally comparable to that of whole grains even if, compared to the latter, the pellets have greater durability and a more uniform diffusion of the active ingredient inside the bait. The durability of the product satisfies the need of mice and rats to gnaw.

Paraffin baits are formulations in which the active ingredient and other ingredients are mixed with paraffin. These formulations have been developed to limit the perishability of rodenticide baits, especially in environments with high humidity.

However, these formulations have the drawback of having a rather modest palatability. Until a few years ago, the paraffin bait was formulated with a classic procedure: the melted paraffin was mixed with the ingredients, then it was poured into molds, where it consolidated. The high paraffin content (up to 50%), the strong heating undergone by the ingredients and their uneven distribution inside the bait significantly reduce its palatability.

Two formulation techniques have recently been developed which allow to obtain paraffin baits with better palatability: the paraffin bait obtained by means of the compression technique (ovules) and the paraffin bait obtained by the extrusion technique. The extrusion technique allows to obtain blocks that allow them to be fixed inside the poisoning stations and not to be easily moved by rodents.

The paraffin baits are particularly suitable for external use as they incorporate the active principle in the paraffin and do not allow the water to extract it.

Track or contact powders are designed to be placed on the habitual paths of rodents or blown into their burrows. The rodent, once sprinkled with dust, will inevitably try to clean itself using the tongue, and will thus take on the active principle. Although powders are an extremely effective means of controlling rodents, the system is nowadays rarely used due to the high risk of environmental contamination.

The baits in the formulation of gel or greasy bait are endowed with good palatability and have the important advantage of not being able to be moved by rodents. They also keep fresh for a long time. In some cases the fresh gel bait or greasy bait can exploit the identical mechanism of the dust, whereby the mouse, in an attempt to clean up the hair with its tongue, ingests the active ingredient.

The concentrated liquid formulations are indicated for the formulation of baits and must be mixed with appetizing substances that can vary according to the eating habits of the population of mice and / or rats that you want to fight. The liquid contains dyes (blue, green, red) for coloring the bait.

A very effective and palatable formulation consists of the paste bait that can be contained in filter paper sachets that make positioning and passage easy. It is a floury paste mixed with animal and vegetable fats to which antioxidant products are added to avoid rancidity.

The paste bait contains all the ingredients of greatest palatability for rodents, and thanks to its rather oily consistency it presents an excellent palatability in many situations, especially where only dry food is available. The packaging in filters or sachets allows a tempting diffusion of the aromas and attractive substances contained. The duration of this formulation is good overall, even if the sachets often tend to exude excessive quantities of oil when the temperature becomes high. This is a very frequent case in the summer inside the poisoning stations, when the temperature can exceed 50 ° C.

10th International Working Conference on Stored Product Protection - Julius-Kuhn-Archiv, 425,2010 pages 950-952 describes baits, not containing a poisonous active ingredient, also called placebo baits, which use fluorescent dyes.

Placebo baits containing fluorescent dyes are marketed under the name Detex with Lumitrack Biomarker and Fluoro-Bait by Bell Laboratories and by Killgerm respectively.

The main purpose of the placebo baits is to monitor the activity of murine species, as the fluorescent color is transferred to the faeces and these can be easily localized, for example, with the use of emission lamps UV. Said placebo baits are therefore used for the purpose of identification and not for the control of murine species.

One of the main problems of currently known rodenticide baits is that of attracting other animal species such as, for example, dogs, cats, pigs, etc. with consequent direct or indirect involuntary poisoning of possible predators of the pests.

Another serious problem presented by current rodenticides is represented by the fact that about 50% of the rodenticides currently used remain unused, causing the release of dangerous active ingredients into the environment, thus proving to be a source of pollution for the environment. environment.

In fact, it is known that many animal species show distrust of objects or situations that are new to them. This behavior, known as neophobia, is well known, for example, for mice and rats who tend to avoid objects introduced into their territory and unknown foods. Neophobia can therefore save specimens of these animals from traps and poisoned baits.

Summary of the invention

At present, therefore, the need is felt to have more and more effective preparations for rodenticide actions with a high palatability; in such a way as to reduce the quantity of toxic active principle and thus minimize the risks of pollution due to a possible dispersion in the environment of the active ingredients contained therein.

The Applicant has found that the replacement of the dyes traditionally used in rodenticide baits with luminescent dyes reduces the neophobia typical of murine species, increasing at the same time the attractiveness and appetite of the baits themselves. This entails, on the one hand, the decrease in the quantity of unused baits remaining on the territory and on the other the possibility of reducing the percentage of poisonous active principle while maintaining the disinfesting efficacy of the bait itself.

Furthermore, since the luminescent pigments are not digested by rodents, it is possible to immediately recognize, for example, the marked fluorescence of feces (solid and / or liquid) released by mice with the use of a UV lamp. . Thus allowing to verify if the bait was eventually ingested also by non-target species.

Thus, according to a first aspect, the present invention provides a rodenticide bait comprising one or more rodenticide active ingredients and a priming agent containing luminescent dyes.

Particularly, the present invention provides a rodenticide bait which contains one or more rodenticide active ingredients and a priming agent containing fluorescent or phosphorescent dyes or mixtures thereof.

Particularly, the present invention provides a rodenticide bait comprising one or more rodenticide active ingredients and a priming agent containing fluorescent dyes.

According to another aspect of the invention is to provide a method for reducing the rodent population in places frequented by both rodent and non-rodent mammals, and / or avian species, which comprises, that an effective dose of rodenticide bait comprising one or plus rodenticide active ingredients and a priming agent containing luminescent dyes, both ingested by rodents.

Luminescence is a physical phenomenon that consists in the emission of photons of visible or invisible light by materials excited by causes other than the increase in temperature.

A material is called luminescent when it is able to absorb discrete amounts of energy which is subsequently returned in the form of photons of light.

Depending on the nature of the excitation that causes the luminescence, we speak of bioluminescence, chemiluminescence, electroluminescence, radioluminescence, sonoluminescence, thermoluminescence and electroluminescence.

In particular, when the luminescence is activated by an electromagnetic radiation we speak of photoluminescence which includes the phenomena of fluorescence (instantaneous decay) and phosphorescence (decay that continues even after ceasing to irradiate the sample).

The time interval between absorption and emission is typically very short, of the order of 10 nanoseconds. However, in particular circumstances, this interval can be extended to periods of a few minutes or hours.

Thus, fluorescence and phosphorescence are the properties of some substances to re-emit, in most cases at longer wavelength and therefore with lower energy, the electromagnetic radiations received, in particular to absorb radiations in the ultraviolet and emit it in the visible. Fluorescence is distinguished from phosphorescence because in the former the effect is immediate and stops as soon as the energy source is interrupted, while in phosphorescence the effect continues even after.

An example of fluorescence is visible in all materials that contain fluorescent pigments, such as in the ink of highlighters and fluorescent paints. The fluorescent properties of an object often become evident with the use of a Wood lamp, but depending on the materials a shorter wavelength may be required.

Detailed description of the invention

The fluorescent baits according to the present invention use different colors of blue, yellow, orange, red, green, etc. The most visible colors with Wood's pocket lamp are yellow, orange, red. However, good fluorescence is obtained on all samples subjected to UV light.

Examples of fluorescent dyes that can be used in accordance with the present invention include, by way of example, Violet 45, Astral Pink 1 Strong Magenta 14, Cerise 13, Magenta 10, Leser Red 3, Strong Magenta 21, Flame Orange 4, Nova Red 2, Blaze 5, Fire Red 15, Arc Chrome 6, Solar Yellow7, Lunar Yellow 27, Stellar Green 8, Comet Blue 60, UV Blu T070, Invisible Blue 70.

According to one embodiment, particularly suitable fluorescent dyes are Astral Pink, Lunar Yellow 27, Stellar Green, Laser Red 3. Among them, Astral Pink is particularly preferred.

According to an embodiment of the invention, the active rodenticides are acute (single dose) or chronic (multiple dose) rodenticides.

According to a preferred embodiment of the invention, the rodenticidal active principles have a chronic rodenticidal action.

According to an embodiment of the invention, a particularly useful chronic action rodenticide is of the anticoagulant type selected from warfarin, coumachloro, coumatetralil, coumafuril, pivaldione, difacinone, chlorofacinone, bromadiolone, difenacoum, brodifacoum, difethialone and floelecoumafen or their mixtures .

A particularly suitable rodenticide according to the present invention is the IUPAC name 2-hydroxy- 3- [3- (4-phenylphenyl) - 1 tetralinyl] - 4-chromomenone diphenacoum.

According to an embodiment of the invention, an advantageous formulation includes floured baits, cereals, paraffinized extruded blocks, pallets or fresh pasta.

A particularly advantageous embodiment of the invention includes baits of paraffinized extruded blocks or fresh pasta. Comparative palatability experiments between bait with traditional dye and fluorescent dye are illustrated below.

1. Organization of the test

For the palatability test, 2 locations were identified with an ascertained infestation of Rattus norvegicus indicated by the presence of burrows, excrements and walkways.

For the test, fixed stations were used, all of the same shape and size in order to simulate the operational reality, these stations were positioned one week before the start of the test (without rodenticide bait) to reduce neophobia, typical rats; therefore in doing so the rodents present in the infested area have come to recognize the containers containing the bait as objects.

2. Workstations

The 3 prepared positions were placed in the vicinity of the burrows or in any case in the areas where the signs of presence were greater as the rats normally try to travel the shortest possible route between the burrows and the source of food.

4 trays containing a known quantity of fresh pasta (100 g) to be tested were positioned inside the individual stations. In this way the rat had the possibility to choose the most attractive bait or in any case the one that could best satisfy its needs. Checks were performed at weekly intervals to assess the consumption of bait.

The start of the test and control times of the stations are as follows:

T0:

T1: T0 + 2 weeks

T2: T0 + 4 weeks

T3: T0 + 5 weeks.

The collected data was subjected to the analysis of variance and the chi-square test.

3. Results

The trend in bait consumption (expressed in grams) for each single position is summarized in tables 1-3 and illustrated in figures 1-3.

Table 4 and Figure 4 represent the overall consumption of the baits of stations 1-3 expressed in grams at a certain time T3.

The formulation of the sample baits A-D, containing the active principle rodenticide difenacoum (0.005%), with the following differences:

Sample A includes traditional non-fluorescent red staining.

Sample B includes Laser Red 3 staining with fluorescent red dye.

Sample C includes Lunar Yellow 27 with fluorescent yellow dye.

Sample D includes Stellar Green 8 fluorescent green dye.

Table 1

STATION 1

SAMPLE Time 0 Consumption T1 Consumption T2 Consumption T3

Sample A <0 0 4 12>

Sample B <0 12 27 34> Sample C <0 15 26 37> Sample D <0 21 29 39>

Table 2

STATION 2

SAMPLE Time 0 Consumption T1 Consumption T2 Consumption T3 Sample A <0 3 12 21> Sample B <0 21 34 49> Sample C <0 27 33 42> Sample D <0 32 39 47>

Table 3

STATION 3

SAMPLE Time 0 Consumption T1 Consumption T2 Consumption T3 Sample A <0 12 24 39> Sample B <0 19 37 50> Sample C <0 27 39 44> Sample D <0 31 31 42>

Table 4

TOTAL CONSUMPTION FORMULATED at time T3 SAMPLE Total consumption at T3 in grams Sample A <72>

Sample B <133>

Sample C <123>

Sample D <128>

The experiments illustrated above show that the bait with fluorescent colors has an improved palatability of about 70-80%.

The following examples are provided purely for illustrative purposes of the present invention and must not be construed as limiting the scope of protection.

Example 1

Samples of paste bait (or fresh bait) were prepared in dosed portions of 10 g using Astral Pink 1 color produced by the English company Swada whose composition is shown in Table 5.

The materials, after weighing, were loaded into the mixer. Determined quantities of a liquid or semi-solid binder (such as oil and centrifugal lard with antioxidant) were added to the mixture thus obtained. The mixture was mixed for not less than 3 hours and in any case until a homogeneous color and consistency paste was obtained.

Table 5

COMPONENT QUANTITY%

sweetener sodium saccharin BP 0.100

diphenacoum 2.5% glycol 0.210

10,000 soybean oil

denatonium benzoate 5% 0.0200

wheat starch CHAMTOR 8,570

centrifuged lard with antioxidant 15,000

powdered sugar 2.00

low-fat milk powder 10,000

flower flour "00" 53,460

anoxid a-bht food grade 0.04

triethanolamine 85% 0.100

fluorescent color ASTRAL PINK T1 0.400

sorbic acid PV E 200 "CN" 0.100

Example 2

Extruded paraffinized block samples of 25, 100 and 140 grams were prepared using Astral pink color produced by the English company Swada, whose composition is shown in Table 6.

The materials, after weighing, were loaded into the mixer. Determined quantities of a liquid or semi-solid binder (such as oil and centrifugal lard with antioxidant) were added to the mixture thus obtained. The mixture was mixed for 60 min. about to obtain a semi-finished product homogeneous in appearance and color and free of lumps. The formulation thus obtained was transferred through a conveyor belt to the heated tank of the extruder by adjusting the temperature values of the oil, water, dies, pressure and cutting speed each time. depending on the formulation to be made.

Table 6

COMPONENT QUANTITY% sweetener sodium saccharin BP 0.100 difenacoum 2.5% 0.21000 soybean oil 2,000 denatonium benzoate 5% 0.020 icing sugar 1,000

skimmed milk powder 5,000 Flower flour â € œ00â € 48,63 anoxid a-bht food grade 0,04 triethanolamine 85% 0,100 fluorescent color ASTRAL PINK T1 0,300 Vegetable palm wax 12,500 sorbic acid PV E 200 "CN" 0,100 Paraffin in granules 30,000

Claims (12)

CLAIMS 1. Rodenticide bait comprising one or more rodenticide active ingredients and a priming agent, characterized in that said priming agent comprises luminescent dyes. 2. Bait according to claim 1, characterized in that said priming agent comprises fluorescent, phosphorescent dyes or mixtures thereof. 3. Rodenticide bait according to claim 1 or 2, characterized in that the luminescent priming agent comprises fluorescent dyes. 4. Bait according to any one of claims 1-3, characterized in that the fluorescent dye is selected from the group comprising Astral Pink, Lunar Yellow 27, Stellar Green, Laser Red 3 or mixtures thereof. 5. Bait according to claim 4 characterized in that the fluorescent dye is Astral Pink. 6. Bait according to any one of claims 1-5 characterized in that the rhodonticide active principle has a chronic action. 7. Bait according to any one of claims 1-6, characterized in that the rodenticide active ingredient is an anticoagulant. 8. Bait according to any one of claims 1-7, characterized in that the rodenticidal active ingredient is selected from the group comprising warfarin, coumachloro, coumatetrail, coumafuril, pivaldione, difacinone, chlorofacinone, bromadiolone, difenacoum, brodifacoum, difetialone or flocoumafen or their mixtures. 9. Bait according to any one of claims 1-8, characterized in that the rodenticide active principle is difenacoum. 10. Bait according to any one of claims 1-9 characterized in that it is in the form of floured baits, cereals, pellets, paraffinized extruded blocks or fresh pasta. 11. Bait according to any one of claims 1-10 characterized in that it is in the form of fresh pasta baits or paraffinized extruded blocks. A method for reducing the rodent population in places frequented by both rodent and non-rodent mammals, and / or avian species, which comprises, that an effective dose of rodenticide bait according to any one of claims 1-11, is ingested by the rodents.