WO1992011760A1

WO1992011760A1 - Method and container for the conservation of animal organism

Info

Publication number: WO1992011760A1
Application number: PCT/IT1992/000001
Authority: WO
Inventors: Enzo Silingardi
Original assignee: Silingardi, Andrea; Silingardi, Matteo
Priority date: 1991-01-03
Filing date: 1992-01-03
Publication date: 1992-07-23
Also published as: ITMO910003A1; ITMO910003A0; AU1171692A; IT1246018B

Abstract

The method concerns the conservation of small animal organisms such as those for use in fishing as bait, for laboratory research and for biological pest control, said conservation being necessary in order to overcome particularly long periods (of as much as 30-40 days) in particular for distribution, without noticeable loss or depreciation, said organisms furthermore remaining intact and in conditions suitable for rapid recovery of activity; said method consists mainly of inserting said organisms (2) into a container, either rigid (1) or flexible (8, 9), together with special bedding (3'), then performing a rarefaction of the air therein, preferably to approximately 0.8 bars, possibly substituting of the air itself with inert gasses, thus obtaining a halt in activity and development; it can be used, for example, for the conservation of flesh fly larvae for use as bait in fishing sports.

Description

METHOD AND CONTAINER FOR THE CONSERVATION OF ANIMAL ORGANISM

The invention concerns a method for the conservation of animal organisms for use in fishing, in laboratories, for biological pest control in agriculture, the container and packaging relating thereto, that is to say a new process for the conservation, as well as fishing bait such as flesh fly larvae belonging to the genuses Sarcophaga and Calliphora ucilia, of other small animal organisms, for example worms such as Polycheta and Oligocheta for use as bait and Hyrodinea for laboratory use, and also of insects such as Coleopters, Coccinellids, Dipterans, Syrphids, Neuropters, Chrysopids, Hemiptera, Anthocorids, predatory mites (in particular Phytoseidites, Stigmeites, Thrombididites) , all suitable for the destruction of harmful insects and microorganisms: the container and packaging of the product also forming the object of the request for protection. The state of the art is limited to the conservation of flesh fly larvae for use as fishing bait: it consists of a method forming the object of patent application n. 40035 A/80 by the same applicant, which was issued as patent n. 1.071.041, and which, with the aim of use as fishing bait, provided for the conservation of said larvae, presumably for one month or more, under the following conditions:

- conservation of the larvae in an environment having a temperature of from + 3° C to + 6° C;

- humidity of the environment not exceeding 6%; - oxygen exchange equivalent to approximately 97% of the normal requirements, to avoid excessive vitality and thus the development of heat through friction;

- exposure to light limited to handling times; ccnssrvaticn in a sealed container, on a bed of non- absorbent insulating powder considered suitable to prevent dehydration, in a percentage amount of approximately 5% by weight with respect to the larvae and made up of 60% ground corn-cob, 37% of ground polyethylene, plus powdered mint leaves to make up 100%. As regards the container, the following was provided:

- height 5-6 cm, with a length and width suited for use of a container volume 50% lower than that available; - light-permeable material, sufficiently heat-conductive;

- cover sealed sufficiently to prevent escape of the larvae;

- calibrated holes in the cover to allow a minimum of permanent breathing (3% of the effective oxygen requirement);

- auxiliary holes in a screen stuck to the cover, consisting of a film provided with holes having a diameter of between 1 and 2 mm for extraction, by means of sifting, of the insulating powder and for re-animation of the larvae, after their period of reduced activity, before gradual removal of the screen itself. In effect the method and container proposed at that time by the same applicant showed progress with respect to the method then in use, which only provided for the conservation of flesh fly larvae in boxes stocked in a refrigerator with a forced air circulation at temperatures of between - 1° C and + 1° C, with transfer for use into canvas or plastic bags for a time^' not exceeding 24 hours, as, from the sixth day onwards, the mortality rate was of 5%, causing practical inconvenience for periods exceeding 15 days. In effect the method and the container proposed at that time by the applicant made it possible, by means of conservation in a refrigerator, to procrastinate the use of the larvae for up to about twenty days, with a more acceptable overall mortality rate of 30% at the end of said period and with a much lower reduction in weight with respect to that which was seen using the traditional method.

However, even the improvement gained by application of the previous method and container by the same applicant is not sufficient to obtain the desired length for the conservation period, of one month or more, without a notable mortality rate and without a notable decrease in weight: that is to say, to reach the target of more convenient use, for example of flesh fly larvae, as bait for fishing sports. The above prior art can be greatly perfected as regards the possibility of avoiding the above problems concerning flesh fly larvae, furthermore introducing a new method and a new container for the conservation of other species of animal organism: that is to say, as well as those destined for use in fishing other than flesh fly larvae, also of those destined for biological pest control and for laboratory experiments. From the above can be seen the need to solve the technical problem of finding a method, a container and packaging suitable for conserving for long periods various species of fishing bait and small animal organisms in general including those for laboratory use, in particular insects, worms and mites, for use in biological pest control: all this without mortality, or with an extremely low mortality rate, without loss of weight or with an extremely slight weight loss only, and with the possibility of rapid restoration of their functions even at the end of a long period of conservation, due to the requirements of packing, storage, sale and transport to the place of use, or to the necessity for conservation in laboratory for research or experiments in general; the whole also including the possibility of large- scale production, in an economic manner and with reduced dimensions.

The invention solves the above technical problem by using a method which provides for the conservation of the animal organism, to be used as fishing bait, or for biological pest control, or for laboratory uses, immobilized by an anoxic environment, that is to say caused by the absence of oxygen in the environment into which it is put, with the following conditions: container with rarefied atmosphere, preferably at approximately 0,8 bars, or the successive creation of a. controlled atmosphere by insertion of inert gasses, preferably carbon dioxide, or nitrogen, or a mixture thereof, up to atmospheric pressure; - container containing bedding preferably between 10 and 15% by weight with respect to that of the animal organisms contained therein, to prevent on the one hand excessive dehydration, and on the other hand excessive humidity: said bedding being made up as follows: absorbent granular material (without dust to avoid abrasion of the cuticle) such as montmorillonite, zeolite, chalk, kaolin, mucilage, or mixtures thereof 25% disinfectant (for example sorbic acid and its salts, benzole acid and its salts, propionic acid) 5% natural aromas or bacteria chosen to perfume and deodorize 2-10% inert filling, preferably sawdust, or wood shavings, or bran, or corn-cob or polyester shavings, or textile trimmings, or mixtures thereof, or other materials that do not interact with the animal organisms to make 100%

- container impermeable to light; - temperature within the container preferably of 2° C with a tolerance limit of up to 8-10° C and with the possibility of exposure at even up to 15 - 20° C : in the latter case only for a period of 10-20 hours; as regards the container, the following are provided: - material with low light-permeability in the single container or, at least, in the packaging surrounding one or more containers;

- material suitable to undergo the effects of the operation of air-rarefaction and the possible successive operation of substitution of part of the air with inert gasses;

- heat-conductive material;

- material impermeable to gas and liquids, preferably in plastic, which cannot be attacked by the nitrate components and by the gasses which develop immediately after closure or at the moment of re-opening of the container and renewal of contact between the animal organism and oxygen. The following containers have the above mentioned requisites:

- bags, for example in plastic material, suitable for extraction of air and the successive possible substitution by inert gasses of the air extracted; - box-like or tray-like containers, in plastic material, plastic-coated cardboard, cardboard with internal coating in aluminium or other metal or impermeable and non- reactive paint, suitable for the operations indicated above; - box-shaped, or tray-shaped metal containers, in tin- plate, aluminium, or other metal, internally coated, for example with non-reactive paints, again on condition that said containers are suitable for the operations listed above. The box-shaped container must be able to be joined, on the moment of opening, to a perforated lid allowing air exchange between the inside and the outside: the holes in said lid must not be equal to or exceeding the minimum dimensions of the animal organism and of the grains of bedding, for example, in the case of flesh fly larvae, said holes must not exceed a maximum width of 2 mm, in order to avoid escape of said larvae and of the granular bedding. The packing can be multi-layer or single layer: the former, indicated for the storage, transport and commercialization of large quantities, to the detriment of the recovery time of the organisms, is also indicated, for example, for the operations of chumming preliminary to fishing, where rapid return to activity of the larvae is not required; the latter, indicated when the return to activity of the organism must, on the contrary, be practically immediate, as, for example, in the case of larvae used for angling, to the detriment of the weight of each single package, which cannot exceed approximately 200 g without having basic dimensions which would in practice be inconvenient. As regards the volume of the animal organism-bedding mixture in relation to that of the box-like container, in the case of evacuation of the air, given the low degree of vacuum, this will be almost the same as the geometrical volume of the container.

Use of the contents in multi-layer packs, in the case of flesh fly larvae, takes place on average after 5-12 hours from opening, in a natural environment and at a temperature of 18-25° C, whereas for the single layer pack the larvae can be used after only 15-60 minutes.

The advantages obtained by this invention are the following: complete interruption of motorial activity in the animal organisms for extremely long periods, for example about thirty days with zero mortality, and up to even forty days or more with a mortality rate which increases from zero to less than 10-15% overall from the thirtieth day onwards, in the case of larvae for use in fishing; recovery of motorial activity in an extremely brief space of time when compared with the conservation period, even for long conservation periods; large increase in survival rates and weight conservation; no need for manipulation from the moment of closure of the container until the re-opening of the same; an economical process; increased utilization of volume; suspension of the metamorphosis from larva into pupa, in the case of flesh fly larvae, for the whole of the conservation period, in the practical absence of oxygen; inhibition of the damaging development of microorganisms within the container; duration of the residual life of the animal organism equal to that which it would have had without anoxic treatment; possibility of application of the method, of the container and of the packing, to worms, to insects for use in biological pest control and to other small animal organisms for use in laboratories. It should be noted, in particular, that the bedding according to the present invention, when compared with that used in the preceding invention by the same applicant: - gives complete elimination of the humidity produced by the larvae during the brief period lasting from closure of the package until their immobilization, thus preventing the growth and development of harmful microorganisms, the putrefaction of the larvae due to long periods of contact with the humidity, the giving off of bad smells in spite of the presence of the deodorant and the negative effect of presenting the customer with larvae in said state;

- contributes to the speeding up of recovery in the larvae; - protects the cuticle of the larvae from any abrasions, giving them a more attractive look when presented to the customer;

- inhibits the proliferation of microorganisms due to the presence, in said bedding, of the disinfectant; - perfumes the package, neutralizing its tendency to smell unpleasant;

- attenuates the effects of any jolts and gives the package a more attractive look.

Further advantages derive: from the insulation from sources of light, which increases the tendency of the larva to go into diapause, that is to say into the state in which the majority of the physiological activities connected with the development and successive metamorphosis into a pupa are blocked; from the lower temperature due to the absence of motorial activity in the larvae, which causes a much lower production of heat and thus does not require such low cooling temperatures and gives the possibility of transportation even at fairly high temperatures (15-20° C) , although only for relatively short periods: whereas, on the other hand, an even higher temperature (18-30° C) encourages the recovery of the larvae after opening of the container. In the following are listed, in the examples numbered from 1 to 4, the data relating to four prolonged conservation tests carried out on flesh fly larvae of mixed species, that is to say like those to be found on the market, said tests starting from the end of the nutrition period and counting the period of time as from the moment in which the container was closed: EXAMPLE i 80 bags in opaque polyethylene were prepared, each one containing 50 g of larvae in a multi-layer arrangement and 5 g of bedding according to the invention; half of them were closed after rarefaction to 0,8 bars, while the other half, after rarefaction, was first brought back to 1 bar by introduction of a gaseous mixture formed by 25% carbon dioxide and 75% nitrogen.

Surrounding temperature: + 2° C, with thermostatic regulation;

- time in which the motorial activity of the larvae ceased: 1-3 minutes;

- opening of the bags: one every 24 hours, both of the type under depression and of that under controlled gaseous atmosphere, at a temperature of 18° C.

On the opening of each bag the following was invariably found. Up to and including the 29th day, and in both types of bag: larvae dry, absence of bad smells, zero mortality rate. From the 30th day a slight mortality began, showing an increase of approximately 1% per day for the bags under depression and of 1-2% per day for the bags under controlled atmosphere.

At the end of the 40th day the mortality rates were of 10% and 14%, respectively. The times required for recovery of motorial activity increased from 35 minutes on the first day, to 470 minutes on the 40th, as shown in Table 1 given herebelow, and in diagrams B and C, respectively, in Figure 1.

TABLE 1 TIMES REQUIRED FOR RECOVERY OF THE LARVAE IN MULTILAYER PACKS DAYS OF CONSERVATION RECOVERY TIME IN MINUTES

1 2 3 4 5 6 7 8 9 10

11

12

13

14 15

16

17

18

19 20

21

22

23

24 25

26

27

28

29 30

31

32

33

34 35

36

37

38

39 40

EXAMPLE 2

40 bags in opaque polyethylene were prepared, each one containing 100 g of larvae in a multi-layer arrangement and 10 g of bedding according to the invention in an atmosphere rarefied to 0,8 bars; after being set in surroundings with a temperature of 2° C as in Example 1, every 24 hours up to and including the 40th day one of the bags was opened, with the same results as those shown in Example 1 as far as absence of humidity, of bad smells, of gas and of mortalities is concerned, and also observing a state of perfect cleanliness.

As regards the recovery times, compared in Table 1 with those of Example 1, with the exception of a few values which coincide, these show slightly lower or slightly higher values until the eighth day, after which they decrease at an increasingly noticeable rate as from the ninth day. It should be noted that on the first and on the eighth day the recovery times are the same (35 minutes and 130 minutes, respectively) , whereas on the 40th day the recovery time is 410 minutes against the 470 minutes of Example 1. EXAMPLE 3

40 bags were prepared along with those indicated in Example 2, and in the same way, keeping them, however, at a temperature of 18° C. Every 24 hours one bag was opened. The results showing percentage mortality rate, given in diagram A of Figure 1 on Plate 1/4 enclosed herewith, show that mortality begins on the ninth day, with a fairly gradual increase until reaching an overall mortality rate of 30% after about twenty days, thus confirming the negative influence of temperatures increased beyond the governed interval of 2-10° C. EXAMPLE 4 40 bags in opaque polyethylene were prepared, each containing 50 g of flesh fly larvae, with 7,5 g of bedding according to the invention, the whole in a single layer, with rarefaction to 0,8 bars, temperature + 2° C, thermometrically regulated; upon opening of each bag it was invariably found that the larvae were sweet smelling and there was no humidity. The test was above all aimed at ascertaining the time required for recovery of motorial activity during forty days, opening one bag every 24 hours: much shorter recovery times were found than those given in Table 1, the 35 minutes of the first day were reduced to as little as 3 minutes, and, respectively, 470-410 minutes to only 60 minutes. As regards the mortality rate, a slight decrease was noted between the 29th and the 35th day (see curve D in the diagrams of Figures 1 and 2) .

In the following Table 2 the recovery times for Example 4 are given. TABLE 2

RECOVERY TIMES FOR LARVAE IN MONO-LAYER PACKAGE

DAYS OF CONSERVATION EXAMPLE 4

1 3

2 3 3 4

4 4

5 8

6 8

7 10 8 11

9 13

10 13

11 12

12 18 13 23

14 25

15 25

16 28

17 30 18 30

19 30

20 35

21 37

22 35 23 38

24 38

25 40

26 42

27 44 28 45

29 47

30 50

31 50 32 52

33 52

34 55

35 54- 36 53

37 58

38 57

39 60

40 59 Certain forms of realization of the invention are indicated in the four plates of figures enclosed herewith, in which: Figure 1, as previously mentioned, is a diagram showing percentage mortality, as a function of time, for the flesh fly larvae, as found during tests performed under a variety of conditions, the abscissa showing the duration of the test in days, and the ordinate showing the percentage mortality rate found: in said diagram A, B, C and D, respectively, indicate the curves relating to a conservation test at a temperature of 18° C and to three tests carried out at a thermostatically controlled temperature of 2° C: curve D relating to a mono-layer package; Figure 2 shows, on a larger scale, the development of the diagram relating to tests B, C and D performed according to the invention, shown in a compressed manner in Figure 1; Figure 3 is a perspective view of a rigid box-shaped container, the upper surface of which, open before introduction of the larvae, is formed by a hermetically sealed film, said box being provided with a perforated lid for application during use: it is put into depression after filling, with possible successive insertion of inert gas; Figure 4 is a detail, enlarged and shown in cross section on a vertical plane, of a peripheral area of the box according to Figure 3 in its depressed condition; Figure 5 is a partial cross-section like that shown in Figure 4. but relating to the configuration during use, after the hermetically sealed film has been torn off; Figure 6 is a perspective view of a possible container with flexible walls, of the bag kind, packed in a multi-layer arrangement, in its depressed condition; Figure 7 is a partial transversal cross-section of the container according to Figure 6; Figure 8 is a cross- section like that shown in Figure 7, but showing a flexible, single layer container. The following are indicated: with 1 the rigid container, for example made of plastic material, containing the larvae, or the animal organisms in general 2, mixed with bedding material 3^», closed under depression (for example at a pressure of 0,8 bars) by means of flexible film 3, heat- sealed, liquid- and gas-tight, along the edge 4 of the container 1 and provided with tear-away tongues 5; with 6 a lid for reanimation which snaps onto the edge 4, said lid being provided with perforations 7 having a diameter preferably not exceeding approximately 2 mm, set at a distance p of approximately 1 cm in both directions; with 8 a flexible container, for example in polyethylene, for multi-layer packaging; with 9 a similar container, but for single-layer packaging. The packaging process, in the case of flesh fly larvae, takes place in the following manner: the larvae 2, born approximately one week before, that is to say at the end of the nutrition period of their larval phase, are collected, sawdust is added, the whole is sieved and kept in open boxes at a lowest nominal temperature of 2° C, thermostatically controlled, for a preparation period of approximately 24 hours, during which time the motorial activity slows down by even as much as 60-70%; having been extracted from the refrigerator, they are mixed with bedding- 3' in a container and transferred to the dosing hopper on the packing machine, which performs the following operations:

- dosing according to the capacity of the container;

- filling of the container, either rigid or flexible;

- extraction of the air;

- possible substitution of the extracted air with inert gasses;

- hermetic sealing.

The packages are transferred to a refrigerator having a lowest temperature of 2° C (obviously oscillating up to 8- 10° C), from this moment on the packages can be delivered to the seller - even without treatment using cooling means - for transportation and up to the end of the fourth day from closing: after which it is necessary to replace them in a refrigerator (again at a minimum of 2° C with a variation of temperature of up to 8-10° C caused by the thermostat) for at least six hours before use.

Counting the time from the moment of closure of the container, the larvae can be advantageously used after as much as forty or more days, the only obstacle being an increased mortality rate of over 10-15%.

Conservation under depression is found to be more advantageous, and the value of 0,8 bars has been found to be particularly advantageous, although tests relating to higher depression values of up to 0,4 bars have also given good results.

In practical application, the materials, sizes, executive details, percentages can differ from those indicated, although remaining technically equivalent, without for this reason departing from the legal scope of the present invention.

Claims

1. Method for the conservation of animal organisms for us in fishing, in laboratory, for biological pest control i agriculture, comprising the conservation in multi-laye containers with bedding, under cooling, of flesh fly larvae characterized in that the animal organisms are immobilized due to an anoxic atmosphere, in the following manner:

- insertion into the container along with the bedding rarefaction of the atmosphere within said container preferably to approximately 0,8 bars, possibl substitution of the extracted air with inert gasses, fo example 25% of carbon dioxide and 75% of nitrogen, unti atmospheric pressure is regained, liquid- and gas sealing; - conservation at a thermostatically controlled temperatur of 2° C;

- reopening in a natural environment, preferably at 18-25 C for recovery of motorial activity and successive use.

2. Method, according to claim 1, characterized in that the bedding (3') is made up of the following:

- absorbent granular material, for example montmorillonite, zeolite, chalk, kaolin, mucilage, or mixtures thereof 25

- disinfectant, for example sorbic acid and its salts, benzoic acid and its salts, propionic acid 5

- natural aromas or bacteria chosen to perfume and deodorize 2-10 inert filling, preferably sawdust, or wood shavings, or bran, or corn-cob or polyester shavings, or textile trimmings, or mixtures thereof, or other materials that do not interact with the animal organisms to make 100

3. Method, according to claims 1 and 2, characterized i that the conservation of the animal organisms takes place b packing in a multi-layer container or, preferably, in container with a single-layer arrangement, mixed wit bedding, until completely filling the container. - 16 -

4. Method, according to claims 1 and 2, characterized in that for flesh fly larvae said packing takes place in the following manner:

- collection of the larvae (2) at the end of the nutrition period of their larval phase; addition of sawdust and sieving;

- conservation in open boxes in a cooled environment having a thermostatically regulated temperature of 2° C, for a preparation period of approximately 24 hours; - extraction from the refrigerator, mixture with bedding (3^f) and transfer into the hopper of a dosing machine;

- dosing according to the capacity of the container;

- filling of the container, either rigid or flexible;

- extraction of the air; - possible substitution of the extracted air with inert gas;

- hermetic sealing of the container.

5. Method, according to claim 4, characterized in that after packing, the package is transferred into a refrigerator having a minimum temperature of 2° C, until the fourth day from closing of the package, for transportation to the place of use; having completed transportation, another conditioning period at said temperature is provided, for at least 6 hours before use.

6. Container for performance of the method according to claims 1, 2 and 3, characterized in that it is heat- conductive, impermeable to light, to gasses and to liquids, and formed by a bag having flexible walls (8, 9), suitable for rarefaction of the air within.

7. Container for performance of the method according to claims 1, 2 and 3, characterized in that it is heat- conductive, impermeable to light, to gasses and to liquids, non-corrodible, and that it is formed by a box-shaped or tray-shaped container (i) , suitable or rarefaction of the air within; said container being closed on top by a flexible film (3) welded around its perimeter to the edge (4) of said container in a hermetic manner, said film being provided with tear-off tongues (5) for opening and for substitution with a snap-on lid (6), the upper surface of which is provided with perforations (7) for aeration and sieving, preferably of a diameter not greater than 2 mm.