BE1029796B9 - RODONTICIDAL COMPOSITION - Google Patents

Abstract

The invention relates to a rodenticidal composition in the form of a bait, comprising a support and, as active principle, the combination (i) of at least one anticoagulant agent chosen from coumatetralyl, chlorophacinone, difenacoum, bromadiolone , brodifacoum, flocoumafen and difethialone and (ii) at least one synergist chosen from nonsteroidal anti-inflammatories and platelet antiaggregants, said composition comprises an amount by weight of anticoagulant agent less than or equal to 25 ppm and a synergist: anticoagulant agent weight ratio of between 100 and 2500. This composition makes it possible to obtain good results for the destruction of rodents with a reduced level of anticoagulant residues in the target animals and a phenomenon of secondary contamination limit.

Description

RODONTICIDAL COMPOSITION

The present invention relates to the field of pest control and more particularly relates to a rodenticidal composition effective for the destruction of rodents.

European pesticide regulations apply a distinction between (i) biocidal products (protection inside and around buildings) regulated by ECHA and (ii) plant protection products or PPPs (protection of gardens and grounds). agriculture) regulated by EFSA. The main rodent pests requiring control are rats and mice (biocide targets) and voles, mulois and moles (PPP targets).

Two strategies are currently used in the fight against harmful rodents: so-called "violent" poisons and so-called "slow" poisons.

Violent poisons result in the death of the target animal as soon as they are ingested or inhaled. Currently, five active ingredients of this type are authorized in Europe, whether under biocidal or phytosanitary legislation: aluminum phosphide, zinc phosphide, magnesium phosphide, hydrogen cyanide and alohachloralose.

The main disadvantages of these violent poisons are that they only allow a shock treatment, that they require a new treatment as soon as the pests reappear and that they also generate a certain mistrust of rodents.

Slow poisons, on the other hand, cause the death of the target animal within a period generally between three and eight days after ingestion and sometimes require several ingestions of the active ingredient.

Currently, the majority of rodenticides or rodenticide compositions of the "slow poison" type are based on anticoagulants, also called vitamin K antagonists or vitamin K antagonists (or "AVK") because they oppose the action of this vitamin and thus slow down or annihilate coagulation.

Vitamin K plays a key role in the production of a series of proteins essential for blood clotting, according to

A cyclical process. First, vitamin K undergoes a reduction to an active form called vitamin K hydroquinone, catalyzed by the enzyme vitamin K quinone-reductase. This reduced form is then involved in the process of activating proteins essential for coagulation, a process during which vitamin K hydroquinone is transformed into vitamin K epoxide. Finally, the enzyme vitamin K epoxide-reductase makes it possible to reform vitamin K. A vitamin K deficiency is relatively rare, it being recycled almost continuously in a healthy individual.

Anticoagulants are vitamin enzyme inhibitors

K quinone-reductase and vitamin K epoxide-reductase. These therefore break the cycle of vitamin K and after depletion of the stock of the latter, a sharp decrease in blood coagulation appears and finally death which occurs by acute anemia, caused by bleeding (most often internal) occurring a few days after ingestion.

The main advantages of anticoagulants, which make them active substances of choice in rodenticides, are: - High efficacy at low doses in rodents, due in particular to their low blood volume and high heart rate,

- A delay of a few days between the ingestion of the poison and death, which greatly limits the mistrust of the target individuals in relation to the baits (death being of natural appearance without alarming symptoms for the other rodents), - the existence an effective antidote (vitamin K), and - A low impact on the palatability of baits.

Anticoagulants are classified into two generations according to their effectiveness: - first generation anticoagulants including warfarin, coumatetralyl and chlorophacinone, authorized by the European Chemicals Agency (ECHA): they require several consecutive ingestions to be effective , as they show lower persistence in the individual; and - second-generation anticoagulants including difenacoum, bromadiolone, brodifacoum, flocoumafen and difethialone, authorized by /ECHA: they generally only require a single ingestion due to their strong persistence in the individual (up to several months, even after a single food intake) and their median lethal dose is much lower than that of first-generation anticoagulants.

Unfortunately, anticoagulants have a major disadvantage when they are used as active substances in rodenticidal baits: their very strong affinity for the target enzymes and, therefore, their great persistence in contaminated individuals.

This persistence leads to a phenomenon called “secondary contamination”, ie the contamination, by going up the food chain, of the natural predators of the rodent pests targeted. It has actually been observed that the repeated consumption of rodents contaminated with anticoagulants causes fatal poisoning, by accumulation in the tissues of the liver, of birds of prey and foxes, for example.

Consequently, for many years, many efforts have been made to make the active ingredient in rodenticides more effective at a lower dose, in order to reduce in particular the phenomenon of secondary contamination and also the toxicity towards other species, for example humans and domestic animals.

To this end, it is known to combine a rat poison molecule of the anticoagulant type with another molecule (non-rat poison alone) then called “synergist”.

For example, FR2265273 describes a rodenticidal composition making it possible to accelerate or aggravate the appearance of hemorrhagic phenomena and to reduce the doses of absorption of anticoagulants by rodents necessary to obtain fatal hemorrhage. In particular, this composition contains an active principle composed of the combination of an anticoagulant and a synergist of the salicylated derivative type, the active principle comprising from 2 to 10 parts by weight of salicylated derivative for 1 part by weight of anticoagulant . | is also known from the patent application

CN10135691A A rat poison based on coumatetralyl combined with salicylic acid in an equivalent quantity (ratio by weight close to 1). This particular combination is described as making it possible to increase the rate of death of rodents and also to approximately halve the quantity of anticoagulant of traditional rodenticides (thus passing from 250 ppm to 125 ppm).

However, despite all the efforts to develop rodenticides with low anticoagulant doses, health standards and requirements, particularly at European level, are becoming more and more demanding. For example, the strong persistence of AVKs has notably led to the reduction of their maximum authorized content in the baits used by amateurs (lilore circuit) and to their disappearance in the protection of 5 plants (PPP).

This tendency to reduce the maximum AVK content in rodenticides is likely to increase in the future and there is therefore a strong demand in the field for a rodenticide composition with a lower dose than the current compositions (generally comprising 50 ppm of AVK in the so-called “restricted” circuit).

An objective of the present invention is to overcome the drawbacks of the state of the art described above and to follow the trend of European standards.

In particular, an object of the invention is to provide a rodenticidal composition based on an anticoagulant which makes it possible to obtain good results in the destruction of rodents (comparable to the compositions currently used), with a level of anticoagulant residues in the animals targets decreased and thus, a reduced secondary contamination phenomenon.

Another object of the present invention is to provide a rodenticidal composition based on an anticoagulant with good rodent destruction results and reduced toxicity for other species, including humans.

Another object of the present invention is to provide an anticoagulant-based rodenticidal composition with good rodent killing results and good rodent palatability.

To achieve these objectives, provision is made according to the invention for a rodenticidal composition in the form of a bait, comprising a support and,

as active ingredient, the combination (i) of at least one anticoagulant chosen from coumatetralyl, chlorophacinone, difenacoum, bromadiolone, brodifacoum, flocoumafen and difethialone and (ii) of at least one synergist chosen from non-steroidal anti-inflammatory drugs and antiplatelet agents.

In particular, the composition of the invention comprises: - an amount by weight of anticoagulant agent less than or equal to 25 ppm; and - A synergist:anticoagulant agent weight ratio between 100 and 2500.

The invention is thus based on a new and inventive approach. In particular, the inventors have found, surprisingly, that with a very significant increase, compared to the state of the art, in the synergist content, combined with a decrease in the AVK content (and therefore considering a high weight ratio between the two constituents), it was possible to maintain the effectiveness of the rodenticidal composition in comparison with the compositions currently on the market, but by reducing the residue content in the target animal (in particular, in the liver) and consequently reduces the phenomenon of secondary contamination.

Other characteristics, details and advantages of the invention will emerge from the description given below, without limitation.

In the present description and the claims, it is understood that, as used herein, the terms "A", "a" or "the" mean "at least ONE" and should not be limited to "ONE only". , unless explicitly stated otherwise. Additionally, when a range of values is specified, endpoints are included. Finally, all integral and subrange values in the numeric range are expressly included as if explicitly written.

According to the invention, the rodenticidal composition comprises the combination (i) of at least one anticoagulant chosen from coumatetralyl, chlorophacinone, difenacoum, bromadiolone, brodifacoum, flocoumafen and difethialone and (ii) of at least one synergist chosen from non-steroidal anti-inflammatory drugs and antiplatelet agents.

Coumatetralyl, chlorophacinone, difenacoum, bromadiolone, brodifacoum, flocoumafen and difethialone are ISO names used in a known manner in the field of rodenticides but, for the sake of clarity, the anticoagulant agents according to the invention are listed below. below with the correspondence of their ISO name, their international chemical identification and their CAS number: po ere hinaus Iemallonale ns coumatetralyl 4-hydroxy-3-(1,2,3,4-tetrahydro-1-naphihyl) 5836- 29-3

EN chlorophacinone | 2-[(4-chlorophenyl)phenylacetyl]-1H-indene1l,3(2H)- | 3691-35-8 ae difenacoum 3-(3-biphenyl-4-yl-1,2,3,4-tetrahydro-1-naphthyl)-4- 56073-07-5

PT ee LE bromadiolone 3-[3-(4'-bromobiphenyl4-yl}-3-hydroxy-1- 28772-56-7

FN brodifacoum 4-hydroxy-3-(3-{4'- bromo-4-biphenylyl}-1,2,3,4- 56073-10-0 a flocoumafen cis-4-hydroxy-3-( reaction mass 1,2,3,4- 90035-08-8 tetrahydro-3- (4-(4-trifluoromethylbenzyloxy)phenyl)-1-naphthyl)coumarin and trans-4-hydroxy-3-{1,2,3, 4-tetrahydro-3-(4-(4-trifluoromethylbenzyloxy)phenyl)-ee)

hydronaphthalen-1-yl]-4-hydroxy-2H-1-benzo thiopyran-2-0ne

Preferably, the anticoagulant agent of the invention is chosen from bromadiolone, difenacoum, brodifacoum and chlorophacinone. These anticoagulants have shown particularly satisfactory results in the context of the invention.

According to the invention, the rodenticidal composition comprises an amount by weight of anticoagulant agent of less than or equal to 25 ppm.

Preferably, it comprises an amount by weight of anticoagulant agent less than or equal to 24 ppm, 23 ppm, 22 ppm, 21 ppm, 20 ppm, 19 ppm, 18 ppm, 17 ppm, 16 ppm, 15 ppm. More preferably, it comprises an amount by weight of anticoagulant agent less than or equal to 14 ppm, 13 ppm, 12 ppm, 11 ppm, 10 ppm, 9 ppm, 8 ppm, 7 ppm, 6 ppm. Most preferably, it comprises an amount by weight of anticoagulant agent less than or equal to 5 ppm, 4 ppm and even less than 3 ppm. This reduction in the content of anticoagulant agent has an undeniable advantage on the phenomenon of secondary contamination and the toxicity of the composition, as explained above.

According to a particular embodiment, the rodenticidal composition comprises an amount by weight of anticoagulant agent greater than or equal to 2 ppm.

According to the invention, the synergist is chosen from non-steroidal anti-inflammatory drugs and platelet antiaggregants.

As a non-steroidal anti-inflammatory that can be used in the composition of the invention and of interest for its ability to cause gastric and intestinal bleeding, mention will be made in particular of:

- salicylic derivatives (salicylic acid and its salts, acetylsalicylic acid and its salts); - arylacetic derivatives (diclofenac and its salts, aceclofenac, sulindac, ketorolac, etc.); - 2-arylpropionic or profen acids (ibuprofen, ketoprofen, dexketoprofen, naproxen, oxaprozin, flubiprofen, etc.); - indole derivatives (indomethacin, proglumetacin, tiaprofenic acid, etc.); - oxicams (meloxicam, piroxicam, tenoxicam, etc.); - cyclooxygenase inhibitors releasing nitric oxide (naproxcinod, etc.); - sulfonanilides; - coxibs (celecoxib, etoricoxib, rofecoxib, valdecoxib, etc.); - phenylbutazone; - niflumic acid; - N-arylanthranilic acids or phenamic acids.

As a platelet antiaggregant that can be used in the composition of the invention and of interest for its action on another important parameter of blood coagulation during hemorrhage events, mention will be made in particular of: - salicylic derivatives (salicylic acid and its salts, acetylsalicylic acid and its salts); - adenosine diphosphate receptor inhibitors (clopidogrel, ticlopidine, prasugrel, etc.);

- phosphodiesterase inhibitors (dipyridamole, cilostazol, etc.); - analogues of adenosine triphosphate (Ticagrelor,

Elinogrel, …).

According to a preferred embodiment of the invention, the synergist is a salicylated derivative chosen from salicylic acid and its salts and acetylsalicylic acid and its salts. These synergists have shown particularly satisfactory results. Most preferably, the synergist is chosen from salicylic acid and acetylsalicylic acid.

According to an advantageous embodiment of the invention, the composition comprises a synergist:anticoagulant agent weight ratio greater than or equal to 150, or even greater than or equal to 200.

Preferably, it comprises a synergist:anticoagulant agent weight ratio greater than or equal to 250, greater than or equal to 300, greater than or equal to 350, or even greater than or equal to 400. This has the advantage, combined with the low anticoagulant content according to the invention, to further improve the desired effects, namely to maintain the effectiveness of the rodenticidal composition by reducing the residual AVK content in the target animal.

According to another advantageous embodiment of the invention, the composition comprises a synergist:anticoagulant agent weight ratio of less than or equal to 2000, or even less than or equal to 1750. Preferably, it comprises a synergist:agent anticoagulant less than or equal to 1500, less than or equal to 1250, or even less than or equal to 1000. This has the advantage, combined with the low anticoagulant content according to the invention, of obtaining the desired effects, namely maintaining the efficacy of the rodenticidal composition by reducing the persistence effect of AVK while controlling the cost of manufacturing the composition (optimization of the efficacy/cost ratio).

According to the invention, the rodenticidal composition is in the form of a bait and comprises a support, host of the active principle.

Depending on the use, the target animals and other parameters such as the place of treatment and the desired palatability, the support according to the invention may comprise, by way of examples: - one or more cereal(s); and/or - one or more flour(s) of vegetable or animal origin; and/or - one or more fat(s) or oil(s) of vegetable or animal origin; and/or - One or more paraffin(s); and/or - ONE OR more carbohydrate(s); and/or - one or more proteins; and/or - milk powder; and/or - ONE OR more inert materials, such as, for example, talc or kaolin.

In particular, cereal-based starches are advantageous because they are probably the most palatable to mice and voles; flour and fat mixtures are the most palatable to rats; and Paraffin-embedded grain and fat blends (wax blocks) are ideal for reaching target animals in moist environments, such as sewers, although they are generally less attractive.

The rodenticidal composition according to the invention can advantageously also comprise one or more additive(s)

such as, for example, colorants, flavors, preservatives and/or antioxidants.

According to a preferred embodiment, the composition of the invention also comprises a sedative agent chosen from benzodiazepines.

The rodenticidal composition according to the invention is preferably in the form of granules, pellets, tablets, agglomerated foods, impregnated or coated cereals, powders (intended to be spread over the passage of rodents and in their burrows, "track powder" or "contact powder").

It can also be in the form of fresh or dehydrated meat or fish bait; in the form of fresh or dehydrated fruit or vegetables, in the form of an aqueous OR oily solution or suspension or any other alcoholic or non-alcoholic liquid (for example, milk).

It is understood that the present invention is in no way limited to the embodiments described above and that modifications can be made thereto without departing from the scope of the claims. It is further understood that the invention also encompasses all possible combinations of features and preferred features, described herein and cited in the claims.

Additionally, the following examples are provided for illustrative purposes and are not intended to limit the scope of this invention.

Examples

To show the effectiveness of the rodenticide composition of the invention, the results of comparative destruction tests carried out on rodents by ingestion of rodenticide baits are set out below.

The tests were carried out, in particular, according to the document “Guidance on the Biocidal Products Regulation Vol II, Efficacy,

Assessment and Evaluation, Version 3.0, April 2018, Appendix 13

Laboratory studies for rodenticides: bait choice test”.

Example 1

The objective of this example is to study the effectiveness on mice (Mus musculus) of a bait according to the invention comprising 2.5 ppm of brodifacoum and 4000 ppm of salicylic acid, compared to 3 baits comprising respectively 4000 , 8000 and 12000 ppm salicylic acid alone (grain baits).

Baits:

The compositions of the prepared baits are as follows: (morediont (Sven (9) | Quantity (g) | Quantity (g) | Quantity (g)

Protocol:

Tests were carried out on 40 mice, 10 per type of bait (5 males and 5 females).

The trial was divided into three periods: pre-test period, test period and post-test period: - During the pre-test period, the animals were placed in experimental cages containing litter, 4 days at least before the start of the test. During this acclimatization period, standard food pellets (SAFE reference A04) and drinking water were given ad libitum. Each cage was equipped with a hopper.

Before the start of the test period, it was necessary to make sure that the animals liked each other normally. After acclimatization, two food jars (each containing about 10 9.) were filled with standard food. All other food was removed, but water remained freely available. The amount of food placed in each pot was sufficient to meet the daily needs of each animal. Food intake was determined, so all unused food (i.e. food left in the jar) and scattered food were collected and taken into account by weighing to determine the amount of food that did not was not eaten. All unused food was discarded and the jar was filled with a fresh supply, to ensure its palatability. This procedure was repeated for 3 more days and on the last day (of this pre-treatment period). The total quantity of food consumed by each rodent was thus calculated each day. All rodents ate normally, so no previously selected animals were rejected.

A clinical observation was made by a qualified person during this pre-test period in order to avoid any abnormal behavior or observation that could compromise the study. - The test period lasted 4 days, from D0 to D4.

For bait 1 (2.5 ppm brodifacoum; 4000 ppm salicylic acid), at D0, the standard laboratory food was removed and replaced by 109 of bait 1 (A) and 10g of standard laboratory food (reference, B}, in two clean jars Each day the hopper was weighed, readjusted and all unused magnets/bait discarded, and a fresh amount of A and B were placed in clean jars.

Losses were also determined. The daily consumption was measured for A and B, and the respective consumptions were determined according to the body weight of the animals. This procedure was repeated daily during the testing period.

After D4, the animals were returned completely to the standard diet.

The total consumption in this protocol is given by the sum of the consumptions of A and B. Palatability values

A can thus be determined according to the formula A+B×100, A being the daily consumption of the bait A, and B the daily consumption of the standard food for the 10 mice concerned.

If the palatability is less than 40% then A is less palatable than B. If the palatability is between 40 and 60%, A and B have the same palatability.

And, if the palatability is greater than or equal to 60%, A is more palatable than

B.

For each of the baits 2-3-4 (salicylic acid alone), at D0, the standard laboratory food was removed and replaced by 10 g of bait, in a clean pot. Each day the hopper was weighed, readjusted and any unused bait discarded, and a fresh amount of bait placed in a clean jar. Losses were also determined. - During the post-test period (started at 15), the animals were observed at least once a day and any signs of toxicity and mortality were recorded.

Results :

The palatability assessment during the test period gave the following results:

Daily consumption (g)

Bait 1 (A) Food Report

BRODIFACOUM 2.5ppm + palatability standard

Sal. Ac. 4000ppm reference (B) | of bait 1 (%)

Mean

This shows that bait 1 according to the invention is more palatable than the standard reference food. In addition, a bait is considered to meet the palatability conditions according to the European standards in force (Guidance on the BPR: Volume || Efficacy -

Assessment and Evaluation (Parts B+C) if the appetite ratio is greater than or equal to 20%.

The evaluation of mortality (& individual death) during the test and post-test period gave the following results: - 100% mortality for bait 1 (brodifacoum 2.5ppm + salicylic acid 4000ppm) between D5 and D7 for the males and 100% mortality between D4 and D6 for females, which demonstrates a very good effectiveness of the bait according to the invention having a very low quantity of AVK (2.5 ppm) compared to the baits currently used on the market .

In addition, the weight loss results (maximum 13.9% loss) show that no animal suffered (an animal is considered to be suffering if the weight loss is greater than 15%) and that, therefore, , their deaths are attributed to ingestion of bait 1. This is confirmed by dissection results which showed signs of poisoning such as bleeding around the joints, bleeding from the mouth or nose, and bait in the stomach. - 0% mortality for baits 2, 3 and 4, including only the synergist in variable and significant quantity. The synergist therefore has no lethal activity when used alone, even in very high amounts.

Example 2

The objective of this example is to study the effectiveness on mice (Mus musculus) of a bait according to the invention comprising 2.5 ppm of brodifacoum and 4000 ppm of salicylic acid, compared to two baits comprising respectively 25 ppm and 2.5 ppm brodifacoum alone (grain baits).

Brodifacoum residue was also measured in mouse liver tissue to assess persistence and potential secondary contamination.

Baits:

The compositions of the prepared baits are as follows:

Bait 1 (INV) Bait 2 Bait 3

Ingredients Quantity (g) Quantity (g) Quantity (g)

Salicylic Acid 299% 4

Protocol:

Tests were carried out on 60 mice, 20 per type of bait (10 males and 10 females).

The trial was divided into three periods: pre-test period, test period and post-test period: - During the pre-test period, the animals were placed in experimental cages containing litter, 4 days at least before the start of the test. During this acclimatization period, standard food pellets (SAFE reference A04) and drinking water were given ad libitum. Each cage was equipped with a hopper.

Before the start of the test period, it was necessary to make sure that the animals liked each other normally. After acclimatization, two food jars (each containing about 10 g.) were filled with standard food. All other food was removed, but water remained freely available. The amount of food placed in each pot was sufficient to meet the daily needs of each animal. Food intake was determined, so all unused food (i.e. food left in the jar) and scattered food were collected and weighed to determine how much food was left in the jar. was not eaten. All unused food was discarded and the jar was filled with a fresh supply, to ensure its palatability. This procedure was repeated for 3 more days and on the last day (of this pre-treatment period). The total amount of food consumed by each rodent was calculated each day. All rodents ate normally, so no previously selected animals were rejected.

A clinical observation was carried out by a qualified person during this pre-test period in order to avoid any abnormal behavior or observation which could compromise the start of the study. - The test period lasted 4 days, from D0 to D4.

At D0, the standard laboratory food was removed and replaced by 10g of bait (1, 2 or 3), in a clean pot. Each day the hopper was weighed, readjusted and all used bait discarded, and a fresh amount of bait placed in a clean jar. Losses were also determined. The daily consumption of bait was measured, and the respective consumption of bait was determined according to the body weight of the animals. This procedure was repeated daily during the testing period.

After D4, the animals were returned to the standard diet. - During the post-test period (started on D5), the animals were observed at least once a day and any sign of toxicity and mortality was recorded. - In addition, on D4, 50% of the animals (5 males and 5 females) for each type of bait were euthanized and then autopsied in order to remove their liver for analysis. At the time of the death of the other animals, for each type of bait, an autopsy was also carried out in order to remove their liver for analysis.

Results :

The results of Example 2 are presented in the table below which shows, for each bait 1-2-3, the amount of brodifacoum absorbed, the average day of death and the average brodifacoum residue in the liver (for non-euthanized animals):

Bait 1 ==

BRODIFACOUM Appäf 2 Appetizer 3

BRODIFACOUM | BRODIFACOUM 2.5ppm + Ac. Salt 25ppm 2 5ppm 4000ppm PP SPP

Average amount of

Brodifacoum absorbed 0.010 0.101 0.011 my

Mean day of D6.3 D5.8 D6.6 mortality

Mean quantity of brodifacoum residues 3.91 36.6 5.04 in the liver (in mg/kg), day of death

In conclusion, bait 1 according to the invention shows efficacy in terms of mortality similar to apopat 2, which corresponds to what is currently used on the market. In addition, the average residue of brodifacoum in the liver of rodents is lower for bait 1 according to the invention in comparison with bait 2 and also with bait 3 (-22%) which comprises the same initial content in AVK and for the same absorbed quantity of AVK.

Example 3

The objective of this example is to study the effectiveness on the Norway rat (Rattus Norvegicus) of a bait according to the invention comprising 2.5 ppm of brodifacoum and 4000 ppm of salicylic acid, compared to two baits comprising respectively 25 ppm and 2.5 ppm brodifacoum alone (bait in grain form).

Brodifacoum residue was also measured in rat liver tissue to assess persistence and potential secondary contamination.

Baits:

The compositions of the prepared baits are as follows:

Bait 1 (INV) Bait 2 Bait 3

Ingredients Quantity (g) Quantity (g) Quantity (g)

Salicylic Acid 299% 4

Protocol:

Tests were carried out on 60 brown rats, 20 per type of bait (10 males and 10 females).

The test was carried out as described in the protocol of Example 2.

Results :

The results are presented in the table below which shows, for each bait 1-23, the amount of brodifacoum absorbed, the average day of death and the average residue of brodifacoum in the liver (for non-euthanized animals):

Bait 1 ==

Bait 2 Bait 3

BRODIFACOUM BRODIFACOUM | BRODIFACOUM 2.5ppm + Ac. Sal 2500m 2 5ppm 4000ppm PP SPP

Average amount of

Brodifacoum absorbed 0.03 0.4 0.04 (mg)

Mean day of D7.2 D7.5 D8.0 mortality

Mean quantity of brodifacoum residues in liver 3.06 37.5 4.83 (in mg/kg), day of death

In conclusion, bait 1 according to the invention shows efficacy in terms of mortality similar, or even better, to bait 2, which corresponds to what is currently used on the market.

In addition, the effectiveness of bait 1 is greater than that of bait 3 which has an identical initial content of AVK. Finally, the average residue of brodifacoum in the liver of rodents is lower for bait 1 according to the invention in comparison with bait 2 and also with bait 3 (-37%) which comprises the same initial content of AVK and for the same absorbed quantity of AVK.

Example 4

The objective of this example is to study the effectiveness on the mouse (Mus musculus) of a bait according to the invention comprising 10 ppm of bromadiolone and 4000 ppm of salicylic acid, compared to two baits comprising respectively 50 ppm and 10 ppm bromadiolone alone (bait granules).

Bromadiolone residue was also measured in mouse liver tissue to assess persistence and potential secondary contamination.

Baits:

The compositions of the prepared baits are as follows:

Bait 1 (INV) | Bait 2 Bait 3

Ingredients Quantity (g) | Quantity (g) | Quantity (g)

Protocol:

Tests were carried out on 18 mice, 6 per type of bait (3 males and 3 females).

The test was carried out as described in the protocol of example 2.

Results :

The results are presented in the table below which shows, for each bait 1-23, the amount of bromadiolone absorbed, the average day of death and the average residue of bromadiolone in the liver (for non-euthanized animals):

Bait 1 = =

Bait 2 Bait 3

BROMADIOLONE BROMADIOLONE | BROMADIOLONE 10ppm + Ac. Sal 50 pom 1000m 4000 ppm PP PP

Average amount of

Bromadiolone 0.12 0.87 0.14 absorbed (mg

Average day of D6.0 D7.3 D6.0 mortality

Mean amount of bromadiolone residues in liver 4.27 25.0 9.7 (in mg/kg), day of death

In conclusion, the bait 1 according to the invention shows better efficacy in terms of mortality compared to the bait 2 which corresponds to what is currently used on the market. In addition, the average residue of bromadiolone in the liver of rodents for bait 1 according to the invention is much lower than for bait 2 and also much lower than for bait 3 (-56%) which comprises the same initial AVK content and for the same quantity of AVK absorbed by the rodents.

Example 5

The objective of this example is to study the effectiveness on the Norway rat (Rattus Norvegicus) of a bait according to the invention comprising 10 ppm of bromadiolone and 4000 ppm of salicylic acid, compared to two baits comprising respectively 50 ppm and 10 ppm bromadiolone alone (bait granules).

Bromadiolone residue was also measured in rat liver tissue to assess persistence and potential secondary contamination.

Baits:

The compositions of the prepared baits are as follows:

Bait 1 (INV) | Bait 2 Bait 3

Ingredients Quantity (g) | Quantity (g)| Quantity (g)

Protocol:

Tests were carried out on 18 rats, 6 per type of bait (3 males and 3 females).

The test was carried out as described in the protocol of example 2.

Results :

The results are shown in the table below which shows, for each bait 1-23, the amount of bromadiolone absorbed, the average day of death and the average residue of bromadiolone in the liver (for non-euthanized animals):

Bait 1 = =

Bait 2 Bait 3

BROMADIOLONE BROMADIOLONE | BROMADIOLONE 10ppm + Ac. Sal 50 pom 1000m 4000 ppm PP PP

Average amount of

Bromadiolone 0.56 2.79 0.55 Absorbed (mg)

Mean day of D6.7 D7.0 D7.3 mortality

Mean quantity of bromadiolone residues in the 5.9 25.0 7.03 liver (in mg/kg). death day

In conclusion, bait 1 according to the invention shows a slightly better efficacy in terms of mortality compared to bait 2 which corresponds to what is currently used on the market.

In addition, the average residue of bromadiolone in the liver of rodents for bait 1 according to the invention is much lower than for bait 2 and also lower than for bait 3 (-16%) which comprises the same initial AVK content and for the same amount of AVK absorbed by rodents.

Example 6

The objective of this example is to study the effectiveness on the brown rat Rattus Norvegicus) of a bait according to the invention comprising 10 ppm of difenacoum and 4000 ppm of salicylic acid, compared to two baits comprising respectively 50 ppm and 10 ppm of difenacoum alone (bait in grain form).

Difenacoum residue was also measured in rat liver tissue to assess persistence and potential secondary contamination.

Baits:

The compositions of the prepared baits are as follows:

Bait 1 (INV) | Bait 2 Bait 3

Ingredients Quantity (g) Quantity (g) | Quantity (g)

Protocol:

Tests were carried out on 18 rats, 6 per type of bait (3 males and 3 females).

The test was carried out as described in the protocol of example 2.

Results :

The results are set out in the table below showing, for each 1-2-3 bait, the amount of difenacoum absorbed, the average day of death and the average residue of difenacoum in the liver (for non-euthanized animals):

Bait 1 = =

Bait 2 Bait 3

DIFENACOUM DIFENACOUM DIFENACOUM

10ppm + Ac. Sal 50 pom 1000m 4000 ppm PP PP

Average amount of

Difenacoum absorbed 0.64 0.75 4.62 (mg)

Mean day of D6.0 D7.0 D4.7 mortality

Mean amount of difenacourn residues 43 130 7.9 in liver (in mg/kg), day of death

In conclusion, the bait 1 according to the invention shows better efficacy in terms of mortality compared to the bait 2 which corresponds to what is currently used on the market. In addition, the average residue of difenacoum in the liver of rodents for bait 1 according to the invention is much lower than for bait 2 and also lower than for bait 3 (-45%) which comprises the same initial content of

AVK and for the same quantity of AVK absorbed by rodents.

Example 7

The objective of this example is to study the effectiveness on mice (Mus musculus) of a bait according to the invention comprising 25 ppm of chlorophacinone and 4000 ppm of salicylic acid, of another bait according to the invention. comprising 25 ppm of chlorophacinone and 4000 ppm of acetylsalicylic acid, compared to a bait comprising 25 ppm of chlorophacinone alone (baits in the form of grains).

Baits:

The compositions of the prepared baits are as follows:

Bait 1 (INV) | Bait 2 (INV) | Bait 3

Ingredients Quantity (g) | Quantity (g) | Quantity (g)

Protocol:

Tests were conducted on 15 mice, 5 per type of bait.

The test was carried out as described in the protocol of Example 2.

Results :

The results are set out in the table below which shows the mortality data for each type of bait:

Bait 1 Bait 2 Bait 3

Chlorophacinone 25ppm | Chlorophacinone 25ppm | Chlorophacinone + Ac. Sal. 2500ppm + Ac. actetylsal. 2500ppm 25ppm nj No

DT. he | I DEAD

EC loves en

This example shows that only baits 1 and 2 according to the invention make it possible to obtain 100% mortality. Even after 15 days, bait 3 without synergist and with the same AVK content does not lead to complete mortality.

Claims (11)

1. Rodenticidal composition in the form of a bait, comprising a support and, as active ingredient, the combination (i) of at least one anticoagulant chosen from coumatetralyl, chlorophacinone, difenacoum, bromadiolone, brodifacoum , flocoumafen and difethialone and (ii) at least one synergist chosen from nonsteroidal anti-inflammatories and antiplatelet agents, characterized in that the said composition comprises: - a quantity by weight of anticoagulant agent less than or equal to 25 ppm; and - A synergist: anti-coagulant weight ratio of between 100 and 2500. 2. Rodenticidal composition according to claim 1, characterized in that the synergist is a salicylated derivative chosen from salicylic acid and its salts and acetylsalicylic acid and its salts. 3. Rodenticidal composition according to one of the preceding claims, characterized in that the anticoagulant agent is chosen from bromadiolone, difenacoum, brodifacoum and chlorophacinone. 4. Rodenticidal composition according to one of the preceding claims, characterized in that it comprises an amount by weight of anticoagulant agent less than or equal to 20 ppm. 5. Rodenticidal composition according to the preceding claim, characterized in that it comprises an amount by weight of anticoagulant agent less than or equal to 10 ppm. 6. Rodenticidal composition according to one of the preceding claims, characterized in that it comprises a synergist: anticoagulant agent weight ratio greater than or equal to 200. 7. Rodenticidal composition according to the preceding claim, characterized in that it comprises a synergist: anticoagulant weight ratio of greater than or equal to 400. 8. Rodenticidal composition according to one of the preceding claims, characterized in that it comprises a synergist: anticoagulant agent weight ratio of less than or equal to 2000. 9. Rodenticidal composition according to the preceding claim, characterized in that it comprises a synergist: anticoagulant weight ratio of greater than or equal to 1000. 10. Rodenticidal composition according to one of the preceding claims, characterized in that the support comprises: - one or more cereal(s); and/or - one or more flour(s) of vegetable or animal origin; and/or - one or more fat(s) or oil(s) of vegetable or animal origin; and/or - One or more paraffin(s); and/or - ONE OR more carbohydrate(s); and/or - one or more proteins; and/or - milk powder; and/or - ONE OR more inert materials. 11. Rodenticidal composition according to one of the preceding claims, characterized in that it comprises a sedative agent chosen from benzodiazepines.