GB2436199A

GB2436199A - Sterile maggot production

Info

Publication number: GB2436199A
Application number: GB0605437A
Authority: GB
Inventors: James Alun Wynne Morgan; Stephen Thomas
Original assignee: ZOOBIOTIC Ltd
Current assignee: ZOOBIOTIC Ltd
Priority date: 2006-03-17
Filing date: 2006-03-17
Publication date: 2007-09-19
Also published as: GB0605437D0

Abstract

Apparatus comprising a semi-rigid plastic moulding forming a shallow face plate A. Incorporated into the structure of the face plate are outlets B to which may be connected tubes D to allow the passage of air into and out of the chamber through bacteria proof filters C. A bag G forms the body of the chamber and is inflated by way of the tubes. Optionally there is a large port E, of sufficient size to enable the passage of a human hand by way of a long sleeve of a thin plastic material secured to the port to access the interior of the chamber. The apparatus is used for the production and growth of maggots for wound cleaning from fly larvae. The apparatus ensures that the maggots produced are sterile. A nutrient source is supplied in pots I. The apparatus may further comprise a transportation chamber (Fig 5) having a chamber and a lid for transporting maggots or pupae from one place to another.

Description

Apparatus and an Improved Method for the Production of and Growth of

Sterile Fly Larvae The present invention is concerned with apparatus and an improved method for the production of fly larvae (maggots) and in particular, sterile fly larvae that are intended to be used in medical applications.

Maggots have been used for many years in the treatment of wounds and local soft tissue infections, especially wounds that contain dead tissue (such as the treatment of gangrene or other wounds associated with ischaemia) . Particularly preferred are larvae of flies of the genus Lucilia, particularly L. sericata the greenbottle fly.

The maggots are typically applied to a wound that contains dead tissue for a few days. It has been shown that in this time maggots will remove necrotic tissue, eliminate bacterial infections and stimulate healing of the wound.

Maggots that are used for this purpose should be free from contamination with micro-organisms, such as bacteria and fungi, which themselves have the potential to cause infections. Such maggots are commonly called medical or medicinal maggots.

To date, maggots used for medical purposes have been produced from clumps of eggs collected from non-sterile flies kept in cages typically formed from gauze, muslin, or wire mesh. In order to produce maggots that are generally free from bacteria and fungi, the eggs are first separated, for example by treatment with water or an agent such as sodium suiphite solution combined with mechanical agitation or manipulation. The separated eggs are then exposed to a solution of antiseptic or disinfectant Numerous solutions have been used for this purpose including alcohol, mercuric chloride solution, formalin, Lysol, chlorine-based disinfectants such as chloramine and various quaternary ammonium compounds.

Following this treatment the eggs are rinsed to remove the chemical residues, then placed into sterile containers containing a suitable sterile food source on which the eggs hatch.

Despite the widespread use of the method it has several major disadvantages: a. Excessive treatment with antiseptics or disinfectants has an adverse effect upon the viability of the maggots developing within the eggs. This means that the time for which the antiseptic can remain in contact with the eggs is limited, so that it may not have adequate time to exert an antibacterial effect upon more resistant types of microbial species such as spore formers.

b. For surface sterilising agents to be effective they must come into contact with every part of each individual egg. This means that total separation of the egg clumps must be achieved in every instance.

c. The process assumes that although the outer surface of every egg is heavily contaminated, the contents are free of contamination. Whilst this is generally true there remains the possibility that an improperly formed or damaged egg will contain bacteria, which are not killed by the chemical treatment.

Typically, maggots produced according to this method are found to be contaminated with Bacillus subtilis and other spore forming species, on a regular basis.

d. The process of egg collection separation and sterilisation is very time consuming and therefore expensive.

e. The toxic effects of the chemical treatments reduce the percentage of maggots that hatch from processed eggs thus reducing yields.

The aim of the present invention is therefore to provide apparatus and methods, which allows for the production of sterile maggots. Such maggots are free from all types of micro-organisms including fungi and aerobic and anaerobic bacteria (including spore formers) Further, the method of production allows for full control and validation of the production technique, which enables the maggots produced in this way to be described as sterile' Although the husbandry of various species of animals, plants and insects in a sterile form has been described previously, the use of axenic cultures of flies for the production of sterile maggots for medical use has not previously been described. In particular, there are practical difficulties involved in producing and maintaining cultures of flies and this is particularly so in the case of large-scale production of sterile maggots.

Therefore, according to a first aspect of the invention, there is provided a maggot production apparatus for the production of sterile maggots, wherein the apparatus includes a sterile container having a chamber into which sterile flies or sterile maggots can be introduced, the chamber having an air supply arrangement including means to prevent microbial contamination of the chamber via said air supply arrangement, so that the viability of the sterile flies or maggots can be maintained in order for said flies or maggots to continue their life cycle and produce further maggots, thereby providing a continual supply of sterile maggots, said chamber also having a fly/pupae/maggot removal arrangement, so that sterile flies/pupae or sterile larvae can be removed from chamber without the risk of contamination of the chamber.

Preferably, at least part of the sterile container allows for the transmission of light into the container.

It is envisaged that the sterile container is formed of one or more of glass or plastic, although for practical reasons, such as the reduction in the risk of breakage, plastic containers are preferred.

In the case where plastic is used, it is envisaged that the plastic is a semi-rigid plastic or a flexible plastic film. A particular example of a flexible plastic is a polyethylene film. However, it is envisaged that the container may be formed of a combination of a semi-rigid plastic and a flexible plastic film.

The sterile container may be reusable. However, generally, to avoid the problems of cleaning and re-sterilization of the containers, disposable cages are preferred.

It is preferred that the sterile container comprises a rigid or semi rigid tray forming a first part of the container and a flexible bag, secured around the periphery of the tray, forming the second part of the container, the first and second parts providing the chamber of the maggot production apparatus.

According to a first embodiment of the invention, the air supply arrangement to the sterile container comprises a positive pressure air supply, which is connected to a port leading to the chamber, so that air can be introduced into the chamber. There may be one or more ports and air supplies to the container.

It is envisaged that the air is introduced into the container by means of a compressor or fan system, and the air is passed through a sterilising filter before it enters the sterile container to ensure the elimination of any form of microbial contamination prior to the air entering the chamber.

According to a second embodiment of the invention there is provided an unpressurized air supply to the container, wherein the container has one or more apertures which is/are covered by an oxygen permeable film or membrane, which provides a filter that is impermeable to micro-organisms. The filter allows the free flow of sterile air into the container and there is no need to use a positive air supply in situations where the permeability of the enclosure wall to oxygen exceeds the respiratory needs of the contained flies.

Examples of material that can form the filter include (but are not limited to) membrane filters similar to the type used for the sterilisation of pharmaceutical products consisting of polyester, nylon or some other suitable material, which contain pores or apertures small enough to prevent the penetration of the filter by micro-organisms.

In systems that do not use the positive supply of air, the chamber may be provided with sterile air by locating them inside cabinets, such as laminar flow cabinets that are fed with sterile air.

Preferably, the sterile container includes a contamination monitor, such a monitor comprises, portion of microbiological growth medium. The microbiological growth medium, which can be provided as for example, an agar plate or as a vial including solid or liquid growth medium is used to detect the presence of bacteria which may have contaminated the container. The bacteria may have settled on the insects' bodies or may be being released through insect faeces.

It is envisaged that the chamber includes nutrients, which maintain the viability of the colony of maggots/flies. The nutrients may be already positioned in the container prior to establishing a colony of flies/maggots. When nutrients are introduced at this early stage, they are sterilised with the container prior

to introduction of any flies/maggots.

However, in a preferred arrangement, there is provided a chamber access arrangement such as air lock

system for the introduction of materials such as

nutrients into the chamber on a continual basis. The access arrangement may also be used for the removal of maggots. It is envisaged that the air lock system includes the use of a glove port so that persons cultivating the sterile maggots can easily access the inside of the chamber. Eggs laid by the flies may be removed from the sterile container by means of the air lock or glove port. The use of a chamber access arrangement is particularly desirable where a colony of flies is maintained for a relatively long period of time to produce a breeding colony for the continuous production of sterile maggots.

It is envisaged that the fly/pupae/maggot removal arrangement comprises an access aperture into the chamber, and a flexible, substantially tubular member having an open end, the periphery of which is sealed around the periphery of the access aperture of the chamber and a closed end, which extends in a distal direction from where the tubular member is attached around the access aperture.

The tubular member is in effect an elongate member into which a hand can be inserted, as well as part of the arm if required. Although the member is described as being tubular, it is no of strict tubular dimensions and can be a glove-like body, with the open end of the glove being fixed around the aperture and the glove part, receiving the hand of a person removing flies/maggots from the chamber. The tubular body is typically around 10-15 cm in diameter and consists of a flexible plastic material that is heat sealed at the second end. The tubular body can be inverted by a person's hand and pushed into the body of the sterile container so allowing that person to manipulate flies, maggots or nutrients or other bodies in the container, without contaminating the interior.

By having a tubular body made of a plastics material, this allows for material to be withdrawn from the sterile container. The body is unfurled from the inverted position but the material is still maintained in the portion of the tubular body in proximity to the person's hand. An area of the tubular body between the first and second ends can then be sealed, for example heat-sealed, which means that the material within the portion of the body held by the hand can form a sealed bag in which the material that has been removed from the sterile container is contained. This provides a self-contained sample material, for example a sample of eggs.

By using this apparatus, the integrity and sterility of the fly colony is contained within a sterile enclosure that can be transported into a laminar air flow cabinet for further manipulation including transfer onto a hatching medium or distribution into containers prior to dispatch for medical use. This process can be repeated as often as required.

When eggs are to be cultivated and grown into maggots, they must again be cultivated under sterile conditions if they are to be used in medical application.

To this end, the eggs are transferred under aseptic conditions into a second container (the growth apparatus), which provides the required conditions for maggot development.

Preferably, the air supply arrangement and the fly/maggot arrangement access the chamber through apertures in the tray of the container.

Therefore, according to a second aspect of the invention there is provided a maggot growth apparatus for the growth of sterile maggots, said apparatus including a first part, provided as sterile container into which eggs to form maggots can be introduced, and a second part, provided as a container cover to seal the sterile container, said apparatus including a source of nutrients to maintain the viability of the maggots that have hatched from the eggs, and an air supply arrangement to allow air to enter the sterile container, said air supply arrangement including anti-contamination means to prevent the introduction of micro-organisms into the apparatus, thereby maintaining a sterile environment in the container.

In a preferred arrangement, the sterile container is a box or tray of rigid or semi rigid material having one or more compartments.

It is envisaged that the container cover is a membrane positioned over and secured around the periphery of the box or tray to seal the one or more compartments of the apparatus.

It is envisaged that the tray is formed of a plastics material, which preferably is formed by vacuum forming, although other methods of construction are

equally acceptable.

The container cover comprises a sheet of non-woven material formed from fibres of cellulose, polyethylene or some other suitable polymer held together by heat compression or the use of a suitable adhesive. Such materials, which can be sterilised by steam or ethylene oxide as they are permeable to air and other gases but impermeable to bacteria.

It is preferred that the container cover includes an area of self-healing material which can be pierced to introduce eggs into the apparatus and which will self-heal once the object introducing the eggs has been withdrawn.

Preferably, a secondary cover is provided, which can be positioned over and preferably clipped over the container cover to protect said cover.

In a preferred arrangement, the air supply comprises one or more apertures into the apparatus, to which a positive air supply can be attached. The positive air supply may be provided by a pump which pumps sterile air into the growth chamber. It is envisaged that the anti-contamination means is provided either by membranes that are impermeable to micro-organisms or an air filtration system, to minimize the risk of any micro-organisms being inadvertently introduced into the sterile growth chamber.

In an alternative arrangement, the air supply arrangement comprises a membrane extending across at least part of a surface of the container through which air can pass, said membrane being impermeable to micro-organisms.

Examples of materials that can for the membrane include that material the form membrane filters similar to the type used for the sterilisation of pharmaceutical products; such materials consist of polyester, nylon or some other suitable material which contain pores or apertures small enough to prevent the penetration of the filter by micro-organisms.

It is envisaged that the air can be supplied to the apparatus through the first part or the second part of the apparatus.

Preferably, one or more of the compartments contains nutrients.

It is envisaged that a first set of one or more compartments contains nutrients while a second set of one or more compartments is free of nutrients.

Preferably, at least part of the first compartment(s) is substantially light free. This is because once maggots have finished feeding they will seek somewhere dark and dry to pupate away from their food source and hence ideally, the maggot growth apparatus contains separate compartments to facilitate feeding and pupation.

In a preferred arrangement, the first and second compartments are joined to one another by channels, through which the maggots may pass from one compartment to the other. Ideally the channels are narrower than the width of the compartments. Such an arrangement allows for feeding and pupation.

It is envisaged that the channels are formed of heat-sealable material. The use of heat-sealable material allows for the growth apparatus to be separated using heat-sealing by dividing compartments from one another. Once maggots have moved to a compartment to pupate, if that compartment is sealed by heat-sealing, it allows for removal of what are now pupation chambers so the pupae can be grown on in other apparatus.

It is preferred that one or more of the compartments includes a graduation scale. The graduated compartment would allow a predetermined number of pupae to be brought into a compartment.

It is envisaged that there is included in the maggot growth apparatus, separate collecting means into which a quantity of maggots/pupae can moved from the compartments and collected and measured so that a required quantity of the maggots/pupae can be transferred to a maggot production apparatus. This may be the original apparatus from which the maggots where produced or a new maggot production or growth apparatus to establish a new breeding colony of flies or maggots. The direct transfer between growth and production apparatus allows for the minimum possible exposure of the pupae to the external environment.

Preferably the maggot growth apparatus includes a connecting arrangement, by which said maggot growth apparatus can be connected to maggot production apparatus, typically a maggot production apparatus according to a first aspect of the invention. This allows for maggots from the maggot production apparatus to be transferred with the minimum risk of contamination from to the maggot growth apparatus and vice versa.

It is envisaged that the connecting arrangement comprises an opening in proximity of a first compartment containing maggots or pupae, said opening being covered by a peelable membrane, which can be peeled back to expose the opening, which can be placed against an opening in another chamber so that maggots/pupae can be transferred from the maggot growth apparatus to another chamber.

It is envisaged that the peelable membrane is re-sealable to close the aperture after maggots have been transferred.

Alternatively, the membrane can be peeled back and the aperture of the maggot growth apparatus is seated over a tube connected to maggot production apparatus, such as the apparatus according to a first aspect of the invention or any other type of fly cage to form the next generation of flies. In this way transfer is completed with the minimum exposure to the environment.

According to a third aspect of the invention there is provided a maggot production facility comprising a maggot production apparatus according to a first aspect of the invention and a maggot growth apparatus according to a second aspect of the invention.

According to a fourth aspect of the invention there is provided a method of continually producing sterile maggots, said method comprising introducing sterile flies into a sterile container, introducing sterile air into the container to maintain the viability of the flies, allowing the flies to produce eggs which hatch into maggots, providing sterile nutrients for the flies/maggots and removing maggots from the sterile container as required using aseptic techniques to prevent contamination of the chamber from external sources.

According to a fifth aspect of the invention there is provided a method of growing maggots, said method comprising placing maggots in a sterile container, said apparatus including a source of sterile nutrients to maintain the viability of the maggots hatched from the eggs, and supplying sterile air into the container to maintain viability of the eggs/maggots, allowing the maggots to move to a pupation area in the container and harvesting the pupae as required, wherein said method is carried out using aseptic techniques to prevent contamination of the container from external sources.

Preferably, the method comprises a combination of the techniques according to a fourth and fifth aspect of the invention, whereby maggots and pupae are passed between the maggot production apparatus and the maggot growth apparatus.

According to a sixth aspect of the invention, there is provided a maggot transportation chamber comprising a chamber, having a lid, said chamber having a removable membrane, positioned over the chamber into which pupae, or maggots can be introduced by way of a sealable aperture within the membrane.

Preferably the transportation chamber includes a lid positionable over the membrane.

It is preferred that the lid is hinged to the chamber. However, the lid may be a separate lid that can be fitted over the chamber by a click fit mechanism.

In a preferred arrangement, the removable membrane includes a tab which can be pulled to lift the membrane from sealed engagement with a peripheral wall of the chamber.

It is envisaged that the transportation chamber can be used to transport pupae or maggots prepared using apparatus or methods according to any of the preceding aspects of the invention to end users that require the maggots.

As can be seen, the apparatus and methods of the invention allow for the continual production of the maggots by using axenic adults which are bacteria-free it is not necessary to separate or sterilize the eggs that are produced prior to use. This reduces mortality, increases yields and impacts favourably upon production costs. Once a sterile fly colony has been established in this way, it is maintained by replacing the adult flies with new stock raised from eggs laid by the preceding generation of sterile flies.

The present invention will now be described by way of example only, with reference to and as illustrated in the accompanying drawings in which: Figure 1 represents a plan view of a sterile maggot production apparatus according to a first aspect of the invention; Figure 2 represents a front elevation of the maggot production apparatus as described in Figure 1; Figure 3 represents a plan view of a maggot growth/pupation apparatus according to a second aspect of the invention; Figure 4 represents a side elevation of the maggot growth/pupation apparatus according to Figure 3; Figure 5 shows a side view of a transportation chamber according to a further aspect of the invention; Figure 6 shows a plan view of a transportation chamber as shown in Figure 5; and Figure 7 shows a side view of a transportation chamber having a hinged lid.

Referring to the drawings and initially to Figures 1 and 2, there is shown an apparatus generally shown as 1 includes a first part which is a semi-rigid comprising a semi-rigid plastic moulding forming a shallow face plate A' that may be square or circular in shape. Although other shapes may be used. Incorporated into the structure of the face plate are two outlets B' to which may be connected two or more tubes D' to allow the passage of air into and out of the cage through bacteria proof filters C' Also incorporated within the structure of the face plate is large port E' which is of sufficient size to enable the passage of a human hand.

A long sleeve of a thin plastic material such a polyethylene bag F' is secured to the port E' . This sleeve is securely closed at the distal end by sealing means such a heat seal or clip.

To the flange around the open rear portion of the moulding B' is secured a second part of the container, comprising a large plastic bag G' forming the body of the cage. This bag is inflated by the air fed by tubes D'.

Within the cage is located a lightweight tray H' which contains numerous compartments, each of which holds a small pot I' with a fitted lid J'. These pots contain food and water and other materials required to maintain the viability of the fly colony and facilitate egg production and collection.

Referring to Figures 3 and 4, there is shown an apparatus comprising a semi-rigid plastic moulding a' forming a shallow tray with multiple compartments (b','c','d') . An air permeable cover e' is heat sealed to the flange around the perimeter of the plastic moulding to form sealed chamber.

A loosely fitting plastic cover f' clips down over the upper surface of the tray to provide additional protection to its upper surface.

Compartments b' and c' are comparable in size and are interconnected by a series of channels g' or by some other means so as to permit the movement of maggots between the two. Access of the maggots to compartment d' is largely prevented by the close proximity of the lid to the flange that separates chambers c' and d'.

The wall of chamber d' may contain simple graduations to provide an indication of the volume of the chamber.

With regard to the fly cage (Figures 1 and 2), in use all the components of the cage are assembled with the exception of the flexible tubes D' . All the materials required to maintain the fly colony are placed in pots in the appropriate compartments of tray H' for example by way of apertures in the seal E'. The flexible sleeve F' is firmly sealed to the port E' and partially sealed at the distal end with a heat sealer.

The entire apparatus is then double or triple wrapped and sterilised by ionising radiation or some other suitable technique, after which the cage is ready for use.

To set up a sterile fly colony, a sufficient number of sterile pupae are introduced into the cage through the opening in the distal end of the partially sealed sleeve using a strict aseptic technique. The sleeve is then heat-sealed closed. The tubes facilitating the passage of air into and out of the cage D' are then attached to a suitable air supply and exhaust and the pupa allowed to hatch.

Control of temperature within the cage is achieved by regulating the temperature of the air supplied to the cages or by controlling the temperature of the room in which the cages are housed.

Once the flies have hatched they are given access to food and water by inverting the sleeve F' and passing the covered hand into the cage through the port E' to remove a lid J' from a pot I' . Provided the plastic that is used in the construction of the sleeve is sufficiently flexible, it is possible to undertake simple manipulations through the wall without physically coming into contact with the sterile contents.

In a similar fashion, by removing the lid from one of the pots that contains a suitable food source, the flies will gain access to a media upon which to lay their eggs.

Once the ovipositing process is complete, by inserting a hand into the sleeve once more, it is possible to retrieve the appropriate pot and withdraw it into the distal end of the sleeve. At this point, two heat seals are made in the sleeve a few millimetres apart and the sleeve is divided between the seals.

In this manner the medium containing the eggs can be transported to a different location for further manipulation inside a sterile container without ever coming into contact with the external environment.

With regard to the production of sterile maggots for medical use, the eggs collected in the manner described are transferred, using an aseptic technique, into the maggot growth/pupation chamber, which is set up as follows.

A layer of growth medium, typically formed from agar containing added nutrients, is introduced into to each of chambers b' and c'. A lid that is permeable to air but impermeable to microorganisms is then heat sealed onto the tray around the outer flange. A small hole h' is present in the lid to permit the introduction of

eggs into the sealed container. This hole is subsequently covered with an adhesive strip i' a portion of which is attached to a low adhesive release backing layer j' that can be easily removed when the strip is to be fixed into position. Alternatively a peel and stick adhesive could be used. The sealed tray containing the growth medium, but not the eggs, is then doubled wrapped and sterilised by ionising radiation or some other suitable technique.

In use the sterile tray is transferred into a sterile environment and a suitable quantity of eggs are aseptically introduced into the tray through the hole which is then sealed by means of the adhesive tab.

The eggs hatch within the container and the maggots are allowed to develop on the growth media until they attain the required size. At this point a small quantity of a suitable sterile aqueous solution is introduced into chamber b' and the maggots are washed off the surface of the growth media.

The liquid containing the suspended maggot is then tipped into chamber c' through the interconnecting channels g' and the washing process is repeated. When the majority of the maggots are in suspension, the solution is then allowed to pass in to chamber d'. This is facilitated by gently squeezing the side of the tray to allow a gap to open up between the tray and the lid above. Once the maggots have been transferred into compartment d' the corner of the lid is peeled back and the maggots are aseptically poured into a sterile container to await transfer into the distribution containers.

With regard to the production of sterile pupae to form the next generation of sterile flies, the same tray is used as before but for this purpose a supply of food is only placed in chamber b' The trays are then closed and sterilised as before.

The eggs are introduced into the sterile chamber and the maggots are allowed to hatch and develop into full grown larvae. During this period they can move freely between chamber b' containing the food and the empty adjacent chamber c'

I

Once they are fully grown the maggots leave the food source and pass into chamber c' to pupate. At this point, by squeezing the sides of the tray, it is possible to open up a gap between the lid and the flange between compartments c' and d' and tip a quantity of pupae into compartment d' using the graduations on the side of the chamber to provide a broad indication of the number of pupae present. Once a suitable number have been transferred into the compartment d' a heat seal may be formed between the two compartments and the two portions separated.

The pupae from chamber d' can then be stored until required for use, or introduced immediately into a new sterile fly cage.

As can be seen in Figure 5, a transportation container for moving maggots/pupae from one place to another is generally shown as K' comprises a chamber 1' and a lid m' . The two parts 1' and m' are joined together by hinge n'. The chamber 1' is usually deeper than chamber m' . There is a membrane p', extending over the middle of chamber 1' . The membrane is preferably a flexible membrane that is impervious to outside contamination in order to maintain the sterility of chamber 1'. A pull tab o' extends from the boundary of the transportation container and provides a pull tab which allows for removal of the membrane from the mouth of the chamber.

Figure 6 shows a plan view of the container of Figure 5. The container is of a generally elongate shape having hinge n' at one end and apex at the other. There are recesses t' along the length of the lid and chamber which are positioned next to detents that allow for the container and lid to be secured by an interference fit.

The membrane P' has an aperture q' through which maggots/pupae can be introduced into chamber 1' . A releasable sealing member r' can be pulled back to reveal aperture and then once maggots/pupae have been introduced into the chamber, can be replaced over the aperture to reseal it and keep the chamber 1' sterile.

Figure 7 shows a side view of a preferred transportation chamber where lid m' and chamber 1' are secured to one another by living' hinge S' The invention is intended to cover, not only a maggot production apparatus, but also a maggot cultivation system including all aspects and embodiments of the invention described, hence, the invention is intended to cover not only single aspects of the invention but also combinations of aspects or embodiments of the invention.

Claims

Claims A maggot production apparatus for the production of sterile

maggots, wherein the apparatus includes a sterile container having a chamber into which sterile flies or sterile maggots can be introduced, the chamber having an air supply arrangement including means to prevent microbial contamination of the chamber via said air supply arrangement, so that the viability of the sterile flies or maggots can be maintained in order for said flies or maggots to continue their life cycle and produce further maggots, thereby providing a continual supply of sterile maggots, said chamber also having a fly/pupae/maggot removal arrangement, so that sterile flies/pupae or sterile larvae can be removed from chamber without the risk of contamination of the chamber.
2. A maggot production apparatus according to claim 1, wherein at least part of the sterile container allows for the transmission of light into the container.
3. A maggot production apparatus according to claim 1 or claim 2, wherein the sterile container is formed of one or more of glass or plastic.
4. A maggot production apparatus according to claim 3, wherein where plastic is used, the plastic is a semi-rigid plastic or a flexible plastic film.
5. A maggot production apparatus according to any preceding claim, wherein the sterile container comprises a rigid or semi rigid tray forming a first part of the container and a flexible bag, secured around the periphery of the tray, forming :* a second part of the container, the first and second parts providing the chamber of the maggot production apparatus.
6. A maggot production apparatus according to any preceding claim, wherein the : . air supply arrangement to the sterile container comprises a positive pressure air S...

: * supply, which is connected to at least one port leading to the chamber.
7. A maggot production apparatus according to claim 6 including a filter to sterilize air before it enters the sterile container.
8. A maggot production apparatus according to any of claims 1 to 5 wherein the air supply is substantially unpressurized air supply.
9. A maggot production apparatus according to claim 8 wherein the container has one or more apertures which is/are covered by an oxygen permeable film or membrane, which provides a filter that is impermeable to micro-organisms.
10. A maggot production apparatus according to claim 9, wherein the filter is formed of one or more of polyester, nylon or material containing pores or apertures small enough to prevent the penetration of the filter by micro-organisms.
Ii. A maggot production apparatus according to any preceding claim, wherein the sterile container includes a contamination monitor.
12. A maggot production apparatus according to claim 11, wherein the contamination monitor comprises a microbiological growth medium.
13. A maggot production apparatus according to any preceding claim including nutrients, which maintain the viability of the colony of maggots/flies.

:.
14. A maggot production apparatus according to any preceding claim including a chamber access anangement for the introduction or removal of materials * SI S into/from the chamber. SS 55 * S S * S
15. A maggot production apparatus according to claim 11, wherein the chamber : * * * access arrangement is an air lock system. S*S*

S

5S555* * S
16. A maggot production apparatus according to claim 15, wherein the air lock system includes the use of a glove port so that the inside of the chamber can be accessed.
1 7.A maggot production apparatus according to claim 14 wherein the chamber access arrangement comprises an access aperture into the chamber, and a flexible, substantially tubular member having an open end, the periphery of which is sealed around the periphery of the access aperture of the chamber and a closed end, which extends in a distal direction from where the tubular member is attached around the access aperture.
18. A maggot growth apparatus for the growth of sterile maggots, said apparatus including a first part, provided as a sterile container into which eggs to form maggots can be introduced, and a second part, provided as a container cover to seal the sterile container, said apparatus including a source of nutrients to maintain the viability of the maggots that have hatched from the eggs, and an air supply arrangement to allow air to enter the sterile container, said air supply arrangement including anti-contamination means to prevent the introduction of micro-organisms into the apparatus, thereby maintaining a sterile environment in the container.
19. A maggot growth apparatus according to claim 18, wherein the sterile container is a box or tray of rigid or semi rigid material having one or more :. compartments. I... * *
20. A maggot growth apparatus according to claim 18 orl9 wherein the container * :* cover is a membrane positioned over and secured around the periphery * of the box or tray to seal the one or more compartments of the apparatus. * S. * I * I...

*.
21. A maggot growth apparatus according to claim 20,wherein container cover includes an area of self-healing material which can be pierced to introduce eggs into the apparatus and which will self-heal once the object introducing the eggs has been withdrawn.
22. A maggot growth apparatus according to any of claims 18 to 21, wherein a secondary cover is provided, which can be positioned over the container cover to protect said container cover.
23. A maggot growth apparatus according to any of the claims 18 to 22 wherein at least compartment(s) is substantially light free.
24. A maggot growth apparatus according to any one of claims 18 to 23 wherein the first and second compartments are joined to one another by channels, through which the maggots may pass from one compartment to the other.
25. A maggot growth apparatus according to claim 24 wherein the channels are formed of heat-sealable material.
26. A maggot growth apparatus according to any of claims 19 to 25 wherein one or more of the compartments includes a graduation scale to measure the number of maggots.
27. A maggot growth apparatus according to any of claims 18 to 26 including separate collecting means into which a quantity of maggots/pupae can moved from the compartments and collected and measured so that a required quantity of the maggots/pupae can be transferred to a maggot production apparatus. S... * * S...
28. A maggot growth apparatus according to any of claims 18 to 27 including : * * connecting arrangement, by which said maggot growth apparatus can be * connected to maggot production apparatus. * S. * I S *S*.
29. A maggot growth apparatus according to claim 28 wherein the connecting arrangement comprises an opening in proximity of a first compartment containing maggots or pupae, said opening being covered by a peelable membrane, which can be peeled back to expose the opening, which can be placed against an opening in another chamber so that maggots/pupae can be transferred from the maggot growth apparatus to another chamber.
30. A maggot growth apparatus according to claim 29, wherein the peelable membrane close the aperture after maggots have been transferred.
31. A maggot growth apparatus according to claim 29, wherein the membrane can be peeled back and the aperture of the maggot growth apparatus seated over a tube connected to maggot production apparatus to allow for transfer of maggots.
32. A maggot production facility comprising a maggot production apparatus according to any of claims 1 to 17 and a maggot growth apparatus according to any of claims 18 to 31.
33. A maggot transportation chamber comprising a chamber, having a lid, said chamber having a removable membrane, positioned over the chamber into which pupae, or maggots can be introduced by way of a sealable aperture within the membrane.
34. A maggot transportation chamber according to claim 33, wherein the transportation chamber includes a lid positionable over the removable :. membrane. * *e* S... * . *SSS
35. A maggot transportation chamber according to claim 34, wherein the lid is hinged to the chamber.

: .
36. A maggot transportation chamber according to any of claims 33 to 35, S...

* : * wherein the removable membrane includes a tab which can be pulled to lift the membrane from peripheral wall of the chamber.

37. A method of continually producing sterile maggots, said method comprising introducing sterile flies into a sterile container, introducing sterile air into the container to maintain the viability of the flies, allowing the flies to produce eggs which hatch into maggots, providing sterile nutrients for the flies/maggots and removing maggots from the sterile container as required using aseptic techniques to prevent contamination of the chamber from external sources.

38.A method of growing maggots, said method comprising placing maggots in a sterile container, said apparatus including a source of sterile nutrients to maintain the viability of the maggots hatched from the eggs, and supplying sterile air into the container to maintain viability of the eggs/maggots, allowing the maggots to move to a pupation area in the container and harvesting the pupae as required, wherein said method is carried out using aseptic techniques to prevent contamination of the container from external sources. * S * *** *15S * * IS. a. is * * S * . a.. * S. * . . S. .5

I

a..... * a