AU718028B2

AU718028B2 - Cockroach bait

Info

Publication number: AU718028B2
Application number: AU67961/96A
Authority: AU
Inventors: Pamela Melrose Burton; Ivana Gluhbegovic; Zlatko Gluhbegovic; Katmerka Tabakovic
Original assignee: Individual
Current assignee: Individual
Priority date: 1995-10-03
Filing date: 1996-10-01
Publication date: 2000-04-06
Anticipated expiration: 2016-10-01
Also published as: AU6796196A

Description

'1

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION (Original) a a a Name of Applicant/Nominated Person: PAMELA MELROSE BURTON Address for Service: DAVIES COLLISON CAVE, Patent Attorneys 1 Little Collins Street, Melbourne, Victoria 3000 Invention Title: "COCKROACH BAIT" Details of Associated Provisional Application: PROVISIONAL PATENT APPLICATION No PN 5771 The following statement is a full description of this invention, including the best method of performint it known to us: 1 011000 2 Technical Field This invention concerns insect baits. More particularly, it concerns bait formulations for use in the control of cockroaches.

Background to the Invention Commercial baits for cockroaches have been marketed for many years. However, there has been no single bait which is effective as an attractant to cockroaches and as a roachicide, (ii) is environmentally friendly, and (iii) is economical to produce.

Disclosure of the Invention It is an object of this invention to provide a new, effective and economical bait for use in the control of cockroaches, which is not environmentally hazardous.

This objective is achieved by a bait formulation which contains boracic acid (which is a known roachicide); (ii) an attractant to cockroaches, namely sugar; and (iii) egg yolk powder (which acts as a binder but which also attracts cockroaches).

In general terms, the cockroach bait formulation comprises a mixture of approximately 1 part (by volume) sugar, 2 parts (by volume) boracic acid, and 4 parts (by volume) egg yolk powder, to which water and oil have been added to form an extrudable paste or dough-like composition.

-3- More specifically, the boracic acid should comprise at least 20 per cent (by volume) of the bait formulation and preferably about 28 per cent of the formulation. However, the boracic acid content of the bait formulation should not exceed 35 per cent (by volume). The sugar content of the formulation should be at least 10 per cent (by volume) and is preferably about 14 per cent. The egg yolk powder is the major constituent of the bait formulation, the ratio of egg yolk powder to boracic acid in the formulation being 10 about 2:1 (by volume). The remainder of the formulation comprises water and oil, in quantities sufficient to produce a stiff paste or a dough-like product which can be extruded.

Thus, according to the present invention, there is provided 0 15 a cockroach bait formulation comprising a mixture of 0• from 20 per cent (by volume) to 35 per cent (by volume) boracic acid; S" at least 10 per cent (by volume) sugar; from 40 per cent (by volume) to 70 per cent (by volume) egg yolk powder; and sufficient water and oil to enable the formulation to be formed into an extrudable paste.

The features of the present invention will be further illustrated in the following description of embodiments of the present invention, which is provided by way of example only.

4 Detailed Description of Illustrative Embodiments The lack of a commercial bait which could effectively control an infestation of cockroaches led one of the present inventors to investigate alternative bait formulations. That inventor drew on established knowledge that boracic acid (H 3

BO

3 also known as boric acid and orthoboric acid) is an effective roachicide and that sugar is an attractant for cockroaches (insects of the family Blattidae). However, experiments conducted in a cockroach-infested environment showed that powder mixtures of boracic acid and sugar were only partially effective, failing to attract many of the cockroaches, and (ii) were awkward to distribute in regions likely to be infested by cockroaches.

p 15 Further experimentation by that inventor led to the discovery that egg yolk powder, which acts as an emulsifier, also appears to attract cockroaches. Egg yolk "powder can be mixed with sugar and boracic acid crystals, and when oil (preferably a vegetable oil and most preferably sunflower oil) and water is added to this mixture, an effective bait for cockroaches, having the consistency of dough or a stiff paste, can be formed. In this consistency, the formulation can be extruded and the extruded material cut into short lengths to provide bait pellets which are easy to distribute within infested, or potentially infested regions (such as behind or inside kitchen cupboards). Provided the constituents of the 5 formulation are present in appropriate concentrations, the formulation is an effective bait for cockroaches.

The approximate proportions of sugar, boracic acid and egg yolk powder are 1:2:4 (by volume). However, variations of the concentrations of these components are possible without destroying the efficacy of the bait formulation. In particular as noted above, the sugar will comprise at least 10 per cent (by volume) of the formulation; the boracic acid (a crystalline powder at room temperature) will comprise from 20 per cent to 35 per cent (by volume) of the formulation; and the egg yolk powder will comprise from 40 to 70 per cent (by volume) of the formulation.

o A preferred bait formulation comprises a mixture of sugar, boracic acid, egg yolk powder, and water and oil in the following proportions:sugar: 14 per cent (by volume) boracic acid: 28 per cent (by volume) egg yolk powder: 56 per cent (by volume) water and oil: 2 per cent (by volume).

Conventional granulated sugar, such as that sold in supermarkets, has been used successfully in bait formulations, but other suitable forms of sugar may be used in the present invention.

6 An optional variation of the bait formulation is the inclusion of flour and an emulsifying powder in place of part of the egg yolk powder component. Up to 20 per cent of the egg yolk powder can be replaced with flour and an emulsifier, but in practice it is not necessary to add more than a fairly small quantity of flour and emulsifier to enable a required consistency (an extrudable paste) of the mixture of compounds to be achieved.

i The usual method of preparation of the bait of this 9*o V-0 10 invention involves the following steps: i. An intimate dry mixture of the sugar, boracic acid and egg yolk powder is formed.

2. Water and oil (and optionally flour and an emulsifier) 99o9 are added to the mixture, and the mixture is formed into a stiff paste.

3. Preferably, the stiff paste is allowed to stand for about 24 hours. However, it is not essential for the paste mixture to stand before the next step, and (ii) the mixture can be allowed to stand for longer than 24 hours (for example, for several weeks).

4. The stiff paste is then extruded (a conventional domestic mincer has been used successfully for the extrusion).

7 The extruded formulation is cut into short lengths or pellets using a knife.

If the bait is not to be used immediately, the bait pellets may be packaged and stored, for up to at least 6 months, in a cool place until the bait is required to control an infestation of cockroaches.

After making the bait pellets, they may be packaged in a cardboard or plastic container (or a container of another suitable material) which has a low height, and (b) contains at least one aperture which enables cockroaches to enter the package, and leave after eating the bait. Such a package makes distribution of the bait, and retrieval of unused bait after an infestation has been controlled, an easy task. In addition, it provides a mechanism whereby 9**e 15 the bait can be transported and placed in position without the formulation coming into contact with the skin of the or o S" user of the bait. It also allows the bait formulation to 9 "breathe", and it prevents cats and other pets from gaining access to the formulation. Preferably the package is provided with a water resistant coating.

The efficacy of the formulation of the present invention has been demonstrated in an independent comparative trial conducted by Agrisearch Services Pty Ltd in the Innisfail region of Far North Queensland, Australia. That trial evaluated the effectiveness of the present invention, which is proposed to be marketed under the trade mark CROAK, and 8 a cockroach bait that is marketed under the trade mark MORTEIN PLUS SUPERBAIT. Twenty-one dwellings infested with the American cockroach Periplaneta americana and the German cockroach Blatella germanica were used as test sites as follows: CROAK baits, in pellet form, were placed inside seven of the test sites; MORTEIN baits were placed inside another seven of the test sites; and 10 the remaining seven sites were not baited, but were used as controls.

The CROAK bait pellets contained 300 g/kg boracic acid and were housed in plastic bait holders. The MORTEIN baits, containing 5 g/kg chlorpyritos as the active ingredient, were housed in child-proof plastic bait holders. Twelve baits were used in each baited site, and depleted baits were replaced as necessary. The trial was conducted for four months.

e e The results of the trial can be summarised as follows: 1. Both the CROAK baits and the MORTEIN baits controlled the American cockroaches more rapidly than the German cockroaches.

2. The CROAK bait was faster than the MORTEIN bait in "knocking down" the population of American cockroaches.

9 3. After one week of baiting with CROAK, the control of the American cockroaches was 87 per cent, whereas the MORTEIN baits achieved only 65 per cent control of American cockroaches after one week.

4. The CROAK bait control of German cockroaches after 1, 2 and 3 months was 100 per cent. The controls of German cockroaches achieved with the MORTEIN bait at the corresponding periods of assessment were 67 per cent, 79 per cent and 83 per cent.

10 5. Both baits caused no adverse effect on humans or animals dwelling in the baited sites.

6. The persons dwelling in the sites baited with CROAK observed a greater decline in the cockroach population than did the persons dwelling in the sites baited with

MORTEIN.

7. During the period of the trial, the cockroach populations in the non-baited, control sites increased.

From the above description of the present invention, and from the outcome of the independent trial in Far North Queensland, it will be apparent that the bait of this invention contains low-cost, readily available ingredients, is essentially "environmentally friendly", is effective when used to attract and kill cockroaches, 10 and represents a significant technical advance in the control of cockroach infestations.

It will be appreciated that although specific examples of formulations in accordance with the present invention have been described in this specification, variations in the exemplified formulations may be made without departing from the present inventive concept.

0 0o 000.

00 *9

Claims

1. A cockroach bait formulation comprising a mixture of from 20 per cent (by volume) to 35 per cent (by volume) boracic acid; at least 10 per cent (by volume) sugar; from 40 per cent (by volume) to 70 per cent (by volume) egg yolk powder; and sufficient water and oil to enable the formulation to be formed into an extrudable C paste. C ft

2. A bait formulation as defined in claim 1, in which the boracic acid content of the mixture is about 28 per S" cent (by volume).

3. A bait formulation as defined in claim 1 or claim 2, in which the sugar content of the mixture is about 14 S*oo* per cent (by volume).

4. A bait formulation as defined in claim 1, claim 2 or claim 3, in which the egg yolk powder content of the mixture is about 56 per cent (by volume). A bait formulation as defined in any preceding claim, in which up to 20 per cent of the egg yolk powder content of the mixture is replaced with a mixture of flour and an emulsifier. 12

6. A bait formulation as defined in any preceding claim, which has been extruded and cut into short lengths.

7. At least one short length of the bait formulation as defined in claim 6 in a container, said container being of low height and having at least one aperture therein which permits a cockroach to enter and leave the container.

8. A packaged bait formulation as defined in claim 7, in o o which the container is made from cardboard or a plastic material.

9. A cockroach bait formulation as defined in claim 1, substantially as hereinbefore described. sees*: *DATED this first day of October 1996 o PAMELA MELROSE BURTON By her Patent Attorneys DAVIES COLLISON CAVE