AU1368201A - Bait composition - Google Patents

Description

P/00/011 28/5/91 Regulation 3.2

AUSTRALIA

Patents Act 1990

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT Name of Applicant: Actual Inventors Address for service is: Executive Director of the Department of Conservation and Land Management David ALGAR and Joe-ann SINAGRA WRAY ASSOCIATES 239 Adelaide Terrace Perth, WA 6000 Attorney code: WR Invention Title: "Bait Composition" Details of Associated Provisional Application No(s): PQ5021 filed on 10 January 2000 The following statement is a full description of this invention, including the best method of performing it known to me:- -2- BAIT COMPOSITION FIELD OF THE INVENTION The present invention relates to the field of toxic baits. Such baits have wide application; being particularly useful for the eradication of animals such as feral cats, foxes, dogs etc. The present invention also provides a method for preparing such baits.

General Those skilled in the art will appreciate that the invention described herein is susceptible to variations and modifications other than those specifically described. It is to be understood that the invention includes all such variation and modifications. The invention also includes all of the steps, features, and compositions referred to or indicated in the specification, individually or collectively.

The present invention is not to be limited in scope by the specific embodiments described herein, which are intended for the purpose of exemplification only.

Functionally equivalent products, compositions and methods are clearly within the scope of the invention as described herein.

Bibliographic details of the publications numerically referred to in this specification are collected at the end of the description. All references cited are 20 hereby incorporated by reference. No admission is made that any of the .4 references constitute prior art.

oeo* Throughout this specification unless the context requires otherwise, the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.

BACKGROUND TO THE INVENTION Feral animals are widely regarded as a serious threat to populations of small to medium sized, native vertebrates in many countries.

-3- The present invention seeks to provide a means for controlling feral animal populations. For ease of description the invention will be described in terms of a bait composition suitable for controlling feral cat populations. It should be appreciated, however, that the invention is not limited to providing a means that is capable only of aiding in the control of feral cats, but clearly relates to the control of any feral animal including foxes and feral dogs that will devour such baits.

The domestic cat has been the most thoroughly studied carnivore in terms of its nutritional requirements. The cat family is nutritionally peculiar, most of which can be directly related to their carnivorous lifestyle. Of all the carnivores the felids are the most specialised meat-eaters.

Predation by feral cats has resulted in the extinction of a number of island mammal populations and the demise of certain re-introduced populations, as reviewed in Smith and Quin (1996) Predation may also seriously affect the continued survival of many native species persisting at low population levels.

Control of feral cats is one of the most pressing problems in the conservation of threatened vertebrates particularly in Australia.

Control methods for feral cats have not been extensively researched. When feral :.:•predator control has been implemented it has generally relied on using standard fox baiting procedures. These routine procedures consist of aerial baiting campaigns using dried meat baits. The recommended baits are cut from kangaroo meat (120g wet-weight), injected with 4.5 mg of sodium monofluoroacetate (1080), and then dried to 40% of their original weight. There are however, no data on the effect of fox baiting on feral cats. There is however, circumstantial evidence that feral cats are not as vulnerable as foxes to existing baiting programs despite being susceptible to 1080 poison with an LD50 of approximately 0.3 0.4 mg/Kg 3).

Thus, there is an urgent need to develop an effective means for controlling animals like feral cat. The present invention seeks to address this problem by providing an improved bait composition that does not suffer from all of the same disadvantages that are typically associated with currently available bait hN -4compositions. In a particularly preferred form of the invention there is provided a bait composition that has properties making it particularly attractive to feral cats.

DESCRIPTION OF THE INVENTION The present invention provides a bait composition, said composition comprising: at least a bait medium; a toxin; and (iii.) at least a flavour enhancer.

Preferably, the composition also contains a digest mixture composed of digested bait medium or meat substance that is attractive to felid animals. If the bait medium is kangaroo meat then the digest may be prepared from kangaroo meat or alternatively it may be prepared from some other type of meat such as for example beef, mutton, lamb, buffalo and the like. "Digest" is the end product of organ/viscera autolysis. Any method known in the art for the autolysis of meat substrates may be used to prepare the digest mixture. By way of example only digest may be prepared by mixing the meat substrate with an acidic solution capable of autolysing the meat.

In addition to a digest mixture, the bait composition may also contain chicken fat S-or a like fatty substance. In this respect chicken fat may be substituted by other fat types or tallow.

The bait medium and flavour enhancers, described herein, individually and collectively preferably increase bait acceptability. Some advantages of such a bait composition include, but are not limited to: relatively cost effective to manufacture the bait is capable of carrying a toxin, (iii.) can be relatively easily manufactured; and can be used in aerial baiting campaigns over broad-scale areas.

Any part of the bait composition may potentially be modified, from its size, weight or individual components. Furthermore, the amounts of the components in the bait composition and the level of flavour enhancers added to the "digest" may also be varied.

The bait medium used in the present invention may comprise or include any meat substance that is attractive to the animals to which the bait is targeted. For example, the bait medium may be kangaroo meat beef, mutton, lamb, buffalo and the like. Most preferably the bait medium is kangaroo meat.

The toxin that is used in the bait may be of any type that is toxic to the animal that the bait is designed for. Preferably, the selected toxin does not alter the flavour of the bait. A particular toxin that is extensively used in baits of the type described herein is 1080 (sodium fluoroacetate). Other toxins that might be used include, for example: cyanide, cholecalciferol, warfarin and gliftor.

Flavour enhancers that are incorporated into the bait composition are preferably selected on the basis of their attractiveness to the animal species to which the bait is targeted. For example, where the bait composition is targeted to feral cats then flavour enhancers that may be employed in the bait composition include, but are not limited to:- MSG (mono sodium glutamate), Fenugreek powder (Trigonella foenum-graecum Metatabi powder (Actinidia polygama), Talin powder also known as Thaumatin (Thaumatococcus daniellfi), and L-alanine.

Other flavour enhancers suitable for use in other bait compositions will be known to those of skill in the relevant art.

In a highly preferred form of the present invention the bait composition comprises: Kangaroo meat mince (for example, in the form of kangaroo meat minced through a 5 mm sieve); Chicken fat (for example, in the form of chicken skins minced lile ~through a 3 mm sieve); and (iii.) Digest and flavour enhancers.

The bait composition described herein is generally prepared by mixing the individual component of the composition together in a ratio of approximately to 80% bait medium; 5 to 30% fatty substance and 1 to 20% digest and flavour enhancers.

o -6- In a particularly preferred form of the invention the bait composition is prepared by blending kangaroo meat mince, chicken skin fat and "digest" together in a ratio of: 70% kangaroo mince; 20% chicken skin fat and 10% digest.

The digest component of the bait is manufactured by adding meat mince to an equal volume of water. AnalaR Orthophosphoric Acid is then added to this mixture at a ratio of 30 ml/2 kg meat mince water mix. The mixture is then heated to boiling point and maintained at this temperature for one hour. The digest is then allowed to cool to room temperature. Flavour enhancers are then added to the digest, the flavour enhancers and the approximate amounts incorporated into the digest are listed below: MSG (mono sodium glutamate) preferably incorporated in an amount of .001 to 10 w/w, most preferably in an amount of .01 to 5 w/w, and even more desirably in an amount of .01% to By way of example only the amount might be 0.1% wlw Fenugreek powder (Trigonella foenum-graecum preferably incorporated in an amount of .001 to 10 w/w, most preferably in an amount of .01 to 5 w/w, and even more desirably in an amount of .01% to By way of example only the amount might be 0.1% w/w Metatabi powder (Actinidia polygama) preferably incorporated in an 20 amount of .001 to 10 w/w, most preferably in an amount of .01 to w/w, and even more desirably in an amount of .01% to By way of example only the amount might be 0.1% w/w Talin powder also known as Thaumatin (Thaumatococcus daniellii) preferably incorporated in an amount of 5000 ppb to 10 ppb w/w, 25 most preferably in an amount of 1000 ppb to 100 ppb w/w, and even more desirably in an amount of 500 ppb to 150 ppb w/w. By way of example only the amount might be 200ppb w/w L-alanine preferably incorporated in an amount of .001 to 10 w/w, most preferably in an amount of .01 to 5 w/w, and even more 30 desirably in an amount of .01% to By way of example only the amount might bel.0% w/w -7- The material is then passed through a sausage-making machine that produces the sausage style cat bait. Sausage skins are used to encase the bait. The bait is described as a chipolata sausage, approximately 50 mm in length, of diameter mm and 25 g wet-weight. The baits are then air-dried to approximately 20 g.

Once dried, the baits are blanched. The blanching process is conducted by placing the baits in boiling water for a period of about two minutes. The blanched baits are then frozen for delivery.

The toxin can be incorporated into the bait medium as the individual sausages are being filled or at any stage in the manufacturing process thereafter. The toxin can be injected as a liquid post-filling, post-drying or post-blanching at the bait-manufacturing site or, after thawing the frozen baits in the field. The toxin may also be incorporated into a gel, capsule, paste or coating and injected into the bait as above or infused into the bait during the filling and automatic linking stage of bait manufacture.

The main reduction of bait availability on the ground is through attack by pests like ant etc. Deterrent compounds that do not affect bait uptake may also been added to the composition. Where ants are a particular pest any ant deterrent compound may be used. Most preferably it is a residual insecticide like "Coopex" .;**•(Robert Linton Pty. Ltd.) that contains the active ingredient permethrin.

EXAMPLES

S. Further features of the present invention are more fully described in the following non-limiting Examples. It is to be understood, however, that this detailed description is included solely for the purposes of exemplifying the present invention. It should not be understood in any way as a restriction on the broad description of the invention as set out above.

Example 1 Study Animals Pen trials were conducted at the Perth Cat Haven (Western Australia).

Fortunately, this provided an opportunity to work with essentially semi-feral cats -8rather than domestic cats in catteries. Cats in the Haven were housed in individual cages. A minimum of 50 cats was used in each trial.

Bait Mediums (Trial 1) The cats were offered a choice of five commercially available, non-toxic bait mediums (baits), described below. A preliminary trial indicated that cats were unable to consume standard fox baits these being too large and dry. As such, a smaller, more moist kangaroo meat bait was used (see Table The baits were randomly placed, approximately 20 cm apart. The baits trialled differed in weight and size. To ensure that bait uptake was not biased because of bait mass, the mediums offered were of comparable mass/size. Their weights are presented in Table 1.

Bait preference was assessed by the bait first selected and consumed by an individual. The baits were offered at the normal time of feeding. Baits were only offered once to any individual cat to avoid any learned behaviour that may have confounded the trial and also to simulate toxic bait delivery in the field.

Bait 1 (Kangaroo meat bait) was cut from kangaroo meat (30 g wet-weight) and then sun-dried to approximately 25 g.

Bait 2 (New Zealand cat bait) was a fish meal-based pellet bait; the pellets weighed 1 g, were 8 mm in length and 2 mm in diameter. The baits were S: 20 produced by Salmon Services (NZ) Ltd. and supplied to Manaaki Whenua Landcare Research New Zealand Ltd.

S* Bait 3 (Incitec bait (D-K9) was a sausage bait, composed of kangaroo meat and fats. Each bait was 35 mm in length and weighed 11 g. The baits were produced by Incitec Ltd., Brisbane.

Bait 4 (Foxoff) was a shelf stable meat substitute bait, each bait weighed 55 g 0 and was 30 mm cubed. The baits were produced by Applied Biotechnologies Pty. Ltd., Melbourne.

Bait 5 (Pussoff) was a prototype fishmeal-based cat bait similar in design to foxoff and produced by Applied Biotechnologies Pty. Ltd., Melbourne.

-9- Table 1. The weight of bait mediums offered Bait medium Bait weight (g) Kangaroo meat New Zealand 10 x 1 Incitec 11 Foxoff Pussoff Bait Additives (Trials 2 and 3) Additives that cause an ingestion response were then investigated to see whether bait uptake could be further enhanced. Cats have a positive taste preference for protein hydrolyzates, meat extracts, phosphate nucleotides and certain free amino acids, such as alanine, proline, lysine and histidine.

Two additives were selected for trial. These substances were applied to the surface of the bait mediums. The first substance was a product called "chicken digest"; it contains the first three substances listed above. Digest is a partially hydrolysed mixture of chicken by products. Of the amino acids, L-alanine was selected as it promotes the greatest taste response in cats.

**The two additives were to be added to the most preferred bait medium from Trial 1. However, as described in the results, there was no significant difference in the most preferred bait uptake for the kangaroo meat bait and Pussoff. Thus, to provide a rigorous examination of response to the additives, separate trials (Trial 2) were conducted for both baits. A third trial was then conducted to compare ooooo the most preferred response from Trial 2. Four baits, described in Table 2, were offered to individual cats in Trial 2 and the two most acceptable in Trial 3. The response to baits with additives was recorded in the same manner as the bait S* 20 medium trial.

Table 2. Bait description for bait with additives trial Bait Bait description 1 Control (no additives) 2 L-alanine w/w) 3 Digest w/w) 4 L-alanine w/w digest w/w) Statistical Analysis Simple descriptive statistics (Chi 2 tests) were used to analyse the data.

Bait Mediums Cats were offered the bait mediums and those which showed interest, initially sniffed each bait type and then selected their choice thus; the experimental design offered a bait choice. Of the 159 cats tested, 104 individuals selected at least one bait medium. Those cats which did not consume a bait were generally shy and remained in their sleeping boxes. Stress of recent capture and their new surroundings most likely accounted for their behaviour and therefore the percentage uptake of baits was not accurately reflected.

A number of individuals consumed more than one bait type and the order of preference was also recorded. Bait acceptance data are presented in Table 3.

Table 3. Bait medium acceptance data. Number of cats consuming individual bait medium types Bait medium Bait Kangaroo New Incitec Foxoff Pussoff preference meat Zealand 1 40 3 24 3 34 2 22 3 12 4 13 3 6 4 5 2 4 4 1 5 3 1 1 1 1 1 3 0 r 11 Analysis of cat's first preferences for the various baits, indicated significant differences in their choice for bait mediums (Chi 2 57.1, 4df., P<0.001). The kangaroo meat and Pussoff baits were the most preferred while the New Zealand and Foxoff baits were the least preferred. Comparison of the preference for kangaroo meat and Pussoff mediums indicated no significant difference between the two bait types (Chi 2 0.5, ldf., P>0.25). When the most preferred bait medium (kangaroo meat) was compared with the third most preferred choice (Incitec) there was a significant difference between bait mediums (Chi 2 1df., P<0.05).

Bait Additives A total of 67 cats were offered a choice of the kangaroo meat bait with additives.

Of these, 50 animals selected and consumed at least one bait/additive type.

Kangaroo meat bait/additive acceptance data are presented in Table 4a.

Table 4a. Kangaroo meat bait/additive acceptance data. Number of cats consuming baitladditive types Bait Control L-alanine Digest L-alanine S: preference (no additive) digest S*1 3 5 35 7 2 6 5 3 14 3 2 10 1 6 4 5 1 0 1 A total of 73 cats were offered a choice of Pussoffladditive bait types, of these 52 consumed at least one bait. Pussoff/additive data are presented in Table 4b.

O* SI -12- Table 4b. Pussoff/additive bait acceptance data. Number of cats consuming baitladditive types Bait Control L-alanine Digest L-alanine preference (no additive) digest 1 5 3 25 19 2 4 4 6 12 3 3 5 0 1 4 3 1 0 0 On both bait mediums there was a significant difference in cat's preferences for the additive offered, (Chi 2 54.6, 3df., P<0.005) and (Chi 2 26.5, 3df., P<0.005) for the kangaroo meat bait and Pussoff bait respectively. In both cases, the bait medium with digest alone was the most preferred choice. The second most preferred choice was that containing alanine digest. This may however, have been because of the digest present as preference for L-alanine baits alone was not significantly different from the control baits in both cases.

A total of 61 cats were offered a choice between the kangaroo digest and Pussoff digest bait types. Of these 50 animals consumed at least one bait type. Acceptance data for these two bait types are presented in Table Table 5. Comparison of kangaroo meat digest and Pussoff digest bait 15 acceptance data. Number of cats consuming bait types Bait Kangaroo meat Pussoff preference digest digest 1 34 16 2 7 11 These data indicate a significant first preference for the kangaroo meat plus digest bait over the Pussoff plus digest bait (Chi 2 6.5, 1df., P<0.025).

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-13- These bait medium trials indicated a distinct ranking of preference for the various baits offered. There was a significant preference for the size-reduced, moist kangaroo meat bait and the prototype fish-meal bait "Pussoff'. This occurred despite several of the mediums being constituted from essentially the same substances. The results suggest that cats display some sensitivity, not only to the taste of a bait, but also to its physical form. Literature on nutrition suggests that the cat is very sensitive to the physical form and taste of its food, more so than the dog and many other mammals.

Of the two additives thought to most improve the taste of the bait mediums, "chicken digest" was significantly more preferred than L-alanine. It would appear, even at this early stage of research, that the use of digest may significantly improve the success of feral cat baiting campaigns.

REFERENCES

1. Smith, A.P. and Quin, D.G. (1996). Patterns and causes of extinction and decline in Australian conilurine rodents. Biological Conservation 77, 243- 67.

2. Mcllroy, J.C. (1981). The sensitivity of Australian animals to 1080 poison.

II. Marsupial and eutherian carnivores. Australian Wildlife Research 8, 385- 99.

20 3. Eason, C.T. and Frampton, C.M. (1991). Acute toxicity of sodium monofluoroacetate (1080) baits to feral cats. Wildlife Research 18, 445-9.

*•go

Claims (11)

1. A bait composition comprising: i) at least a bait medium ii) a toxin; and iii) at least a flavour enhancer

2. A bait composition of claim 1 wherein the bait also contains a digest mixture composed of digested bait medium or meat substance.

3. The bait composition of claim 2 wherein the digest mixture is prepared from at least a meat substance selected from the group consisting of: kangaroo meat, beef, mutton, lamb or buffalo.

4. The bait composition of claim 2 wherein the digest mixture is prepared from kangaroo meat. A bait composition according to any one of the preceding claims wherein said bait contains a fatty like substance. 15 6. A bait composition of claim 5 wherein the fatty like substance is chicken S:fat. ooooo

7. A bait according to any one of the preceding claims wherein a toxin is selected which does not vary the flavour of the bait.

8. The bait of claim 7 wherein the toxin is selected from the group consisting of 1080 (sodium fluoroacetate), cyanide, cholcalciferol, warfarin or gliftor.

9. A bait composition according to any one of the preceding claims wherein S"the toxin is 1080 (sodium fluoroacetate). bait composition according to any one of the preceding claims wherein the flavour enhancer is targeted to feral cats.

11.The bait composition according to any one of the preceding claims wherein the flavour enhancer/s are selected from the group consisting of MSG (mono sodium glutamate), Fenugreek powder (Trigonella foenum- graecum Metatabi powder (Actinidia polygama), Talin powder also known as Thaumatin (Thaumatococcus daniellii), or L-alanine.

12.A bait composition comprising: 50 to 80% bait medium; 5 to 30% fatty substance and 1 to 20% digest and flavour enhancer.

13.A bait composition according to any one of the preceding claims wherein the bait comprises a mixture of 70% kangaroo mince, 20% chicken skin fat and 10% digest.

14.A bait composition according to any one of the preceding claims wherein the digest is prepared by the following steps: i) adding an equal volume of water to meat mince ii) adding acid to mince-water mixture at a ratio of 30 ml acid to 2 kg 15 mince-water mixture iii) heating mixture to boiling point and maintaining heat for approximately one hour; iv) cooling digest to room temperature v) adding flavour enhancer/s. -15 A bait composition according to claim 11 wherein the flavour enhancer is MSG (mono sodium glutamate) 16 The bait composition of claim 15 wherein the amount of MSG (mono sodium glutamate) incorporated ranges from 0.001% to 10% w/w, inclusive. 17 The bait composition of claim 15 wherein the amount of MSG (mono sodium glutamate) incorporated ranges from 0.01% to 5% w/w, inclusive. -16- 18 The flavour enhancer of claim 15 wherein the amount of MSG (mono sodium glutamate) incorporated ranges from 0.01% to 1% w/w, inclusive. 19 The flavour enhancer of claim 15 wherein the amount of MSG (mono sodium glutamate) incorporated is 0.1% w/w. 20 The bait composition of claims 11 wherein the flavour enhancer is Fenugreek powder (Trigonella foenum-graecum L.) 21 The bait composition of claim 20 wherein the amount of Fenugreek powder (Trigonella foenum-graecum incorporated ranges from 0.001% to 10% w/w, inclusive. 22 The bait composition of claim 20 wherein the amount of Fenugreek powder (Trigonella foenum-graecum incorporated ranges from 0.01% to 5% w/w, inclusive. 23 The bait composition of claim 20 wherein the amount of Fenugreek .q powder (Trigonella foenum-graecum incorporated ranges from 0.01% 15 to 1% w/w, inclusive. 24 The bait composition of claim 20 wherein the amount of Fenugreek powder (Trigonella foenum-graecum incorporated is 0.1% w/w. A bait composition of claims 11 wherein the flavour enhancer is Metatabi powder (Actinidia polygama). 26 The bait composition of claim 25 wherein the amount of Metatabi powder (Actinidia polygama) incorporated ranges from 0.001% to 10% w/w, *i inclusive. 27 The bait composition of claim 25 wherein the amount of Metatabi powder (Actinidia polygama) incorporated ranges from 0.01% to 5% w/w inclusive. -17- 28 The bait composition of claim 25 wherein the amount of Metatabi powder (Actinidia polygama) incorporated ranges from 0.01% to 1% w/w, inclusive. 29 The bait composition of claim 25 wherein the amount of Metatabi powder (Actinidia polygama) incorporated is 0.1%. A bait composition of claims 11 wherein the flavour enhancer is Talin powder also known as Thaumatin (Thaumatococcus daniellii). 31 The bait composition of claim 30 wherein the amount of Talin powder incorporated ranges from 5000 ppb to 10 ppb w/w, inclusive. 32 The bait composition of claim 30 wherein the amount of Talin powder incorporated ranges from 1000 ppb to 100 ppb wlw, inclusive. 33 The bait composition of claim 30 wherein the amount of Talin powder incorporated ranges from 500 to 150 ppb w/w, inclusive. 34 The bait composition of claim 30 wherein the amount of Talin powder 15 incorporated is 200 ppb w/w. A bait composition of claims 11 wherein the flavour enhancer is L-alanine. C 36 The bait composition of claim 35 wherein the amount of L-alanine incorporated ranges from 0.001% to 10% w/w, inclusive. 37 The bait composition of claim 35 wherein the amount of L-alanine 20 incorporated ranges from 0.01% to 5% w/w, inclusive. o 38 The bait composition of claim 35 wherein the amount of L-alanine incorporated ranges from 0.01% to 3% w/w, inclusive. 39 The bait composition of claim 35 wherein the amount of L-alanine incorporated is 1.0% w/w. -18- A bait composition substantially as herein described with reference to the examples. 41 A bait composition comprising kangaroo meat mince, chicken fat, digest and flavour enhancers. Dated this TENTH day of JANUARY 2001 Executive Director of the Department of Conservation and Land Management Applicant Wray Associates Perth, Western Australia Patent Attorneys for the Applicant q. 0Sr *6 6* 6 6 4 466666 6 6 6