WO2020096465A1

WO2020096465A1 - Method and device for immobilisation of fish, and applications thereof

Info

Publication number: WO2020096465A1
Application number: PCT/NO2019/050245
Authority: WO
Inventors: Henry Helgheim
Original assignee: Clt Solutions As
Priority date: 2018-11-08
Filing date: 2019-11-08
Publication date: 2020-05-14
Also published as: NO20181436A1

Abstract

There is described a method and a device for immobilization of fish, where the fish is subjected to blinking lights form one or more light sources, as the used blinking light source is turning on and off the light in a given pattern or frequency. A blinking sequence is used (turning on/turning off) for the light that is in the order of 1-20 blinks per second. The fish is preferably treated in a feed line shaped as a hollow body shaped compartment where the inside of the body is equipped with a number of light sources that can influence the fish with light blinks. In accordance with the invention the device is used especially when handling farmed fish, for example where the fish is lead through a counting device, when it is to be vaccinated, or tests are to be done, fish lice is to be removed from the fish, or general transferal of the fish through a transport system. The number of inside light sources is adapted to the volume of the hollow body, the number of fish in the volume, and the visibility (purity) of the water the fish is located in.

Description

METHOD AND DEVICE FOR

IMMOBILISATION OF FISH,

AND APPLICATIONS THEREOF

Field of the invention

The present invention relates to a method and device for immobilization of marine organisms, such as fish, in water. The invention also comprises use of the method and device.

By marine organisms we mainly refer to fish and the present description of the inventive treatment is to be described and used in relation to fish.

By immobilization we refer to aiming to calm down the movements of the fish, in order to keep it completely from moving, or only moving very minimally. This is an issue when it is to undergo different treatments, which is needed bot for handling of so-called wild fish and farmed fish. Examples of conditions where it is necessary to calm down fish are, as an introduction, when it is to for example be carried along a slaughter line or is to be counted in order to assess the number of fish in a confined area such as a fish cage, or when it is to be vaccinated, or treated in order to remove fish lice. Other settings where fish needs to be calmed down for different treatments is also envisioned.

Backgroundd of the invention.

In relation to practical handling of fish, which relates to the present invention, we refer to what is known from Norwegian patent N0342394. Therein is described an instrument for treatment of fish one at a time, from a larger collection of fish. For the treatment (for example vaccination and removal of fish lice, etc.) the fish are led one by one from a larger population, inn through a gradually narrowing pipe, to the treatment chamber itself. In this chamber the free movement room of the fish is reduced by pressing towards each other platforms that are pushed against the fish so that it is left completely immobilized in order for the treatment to be as precise as possible. After the treatment is over, the pressing ends and a outtake port is opened so that the fish may be released out from the pushing chamber. However, it has been found that the fish may still be so uneasy and squirm so much in the very narrow passage that the treatment is imprecise and is made difficult. It is therefore an aim to provide a new method and device for improving the

immobilization in accordance with the invention. This can be used in the method of the above discussed patent, and also to all treatments of fish where it is important to keep it immobilized.

It is known to use light to influence the behavior of fish. Examples are that it is known that fish will normally avoid light and yield /swim away from such a influence. We have however now shown that light still can be used to achieve our goal, i.e. to immobilize the fish, by having the influence of light occurring in a very special manner.

From W02007/145297 and KR20070097305 it is known to completely paralyze squid with very rapid colored light flickers. The squid does not need to be locked up and will not move away from the light, and will remain paralyzed in a death like condition over an extended time period up until slaughtering.

Objects of the present invention

The aim of the present invention is to provide a new method of keeping fish immobilized, for example when it is present in a body of water, or when it is to be lead along a transport line for example for slaughter.

Summary of the invention

The method according to the present invention is characterized in that the fish is exposed to blinking lights from a light source. Further, a light blinking source is used which can turn on and off the light in a given pattern or frequency. In addition, it is preferred that the blinking frequency (turning on/off) of the light is in the range of 1- 20 blinks/flashes per second. In other words, there is 0.05-1 seconds between the start of each light blink. The more frequent the light blinks are, the calmer the fish will be, so in accordance with a preferred embodiment of the present invention the blinking frequency is 3-20 light blinks per second, more preferred 10-20 light blinks per second, and most preferably 13-20 light blinks per second The fish will become more calm the longer time the blinking goes on, and it is preferred that the light blinking continues for at least 4 seconds in order to achieve the desired effect.

In accordance with a preferred embodiment of the method the fish is treated in a feed line in the shape of a hollow body shaped compartment where the inside of the body is supplied with a number of light sources that may affect the fish with light blinks.

In accordance with a preferred embodiment of the method the used number of internal light sources is adapted to the volume of the hollow body, the number of fishes in said volume, as well as the visibility (purity) of the water the fish is in.

Preferably an increasing number of light sources are used in correspondence with the increase in the water volume, the number of fish, as well as the reduction of visibility in the water. The light sources (lightbulbs) light strength is preferably increased in correspondence with the increase in water volume, the number of fish, as well as the reduction of visibility in the water.

In accordance with a preferred embodiment of the method the hollow body is a pipe wherein fish, one by one, is lead to a station where they are exposed to light blinks from the internal light sources in order to immobilize the fish. The residence volume to the fish is preferably reduced in advance by mechanical means (by plates that can be pushed in and out) in the pipe, before the light blinking is starting.

In accordance with a preferred embodiment of the method the hollow body is a pre chamber or a tank with a number of fishes, where the inside of the tank is covered with a number of light sources, both along side walls, the bottom surface and ceiling. More preferably the used pre chamber (12) extends into said pipe (14) as the pre chamber (12) detain fish and also comprise a number of blinking lighthouses (20) in the wall parts, bottom and ceiling parts, in order to prepare the fish - calm them down - before transferal into the pipe (14), by a suitable activation and inactivation (blinking) of the light sources (20) in the pre-chamber.

In accordance with a preferred embodiment of the method white light is used, or light with yellow-red-blue-green color tones. In accordance with a preferred embodiment of the method stroboscope technology is used provide the light blinks, where said stroboscope divide the light up into light blinks.

The device in accordance with the present invention is characterized by a closed container where the fish is kept or a treatment line where the fish is lead to a treatment, where the inside thereof comprises a plurality of light sources that may subject the fish to light gleams.

In accordance with a preferred embodiment of the device the placement of the light sources is on the inside of the container/treatment line, which is in the shape of a pipe, and its characteristics are as given above for the method.

In accordance with a preferred embodiment of the device the light sources comprise stroboscopes in order to produce light blinks, and said stroboscope divide the light into light blinks.

In accordance with a preferred embodiment of the device the light that is released from the light source is a white light, or a light with yellow, blue or green color tones. The light is preferably white, i.e. normal full spectrum light. The use thereof works both in the light and in the dark, in other words it does not have to be dark in order for the fish to react to the light, as long as the light flashes can be seen in relation to the light the fish is being kept in.

The use of the present invention is characterized by that the method and/or device described above is used for handling farmed fish, where the fish is lead through a line to a fish counting device, where the fish is to be vaccinated, or where samples are to be taken from the fish, removal of fish lice from the fish, or general transferal of the fish through a transport system.

By the present invention one has found that it is very advantageous to use visible light, which the fish is exposed to as pulses. That means that the light is blinking on and off with a high blinking frequency or in another off/on frequency. Preferably a stroboscope instrument is used in order to achieve such a light blinking regimen. We have shown that the fish becomes completely paralyzed by this treatment and remains standing/laying completely still. This new inventive method can be used in relation with the device that is described in the already mentioned N0342294. N0342294 describes a device for treatment of fish in a body of water for different conditions, comprising: a housing defining a channel with a treatment chamber suitable for containing one of the fish, and the housing comprises devices for said treatment of the fish in the channel, as the housing comprises means adjacent to the channel which can be rearranged from an initial position and a treatment position, where the treatment chambers residence volume is constricted, where the means to constrict the residence volume of the treatment chamber is made up of curved plates in connection with the outer wall of the channel, which may be moved/pushed outwards and moved/pulled inwardly in order to be rearranged between said initial and treatment positions, wherein the plates comprises:

two mutually sideways arranged plates arranged to be pushed towards and away from another, and is curved so that their abdominal sides are facing each other and their curvature is adapted to a normal curved shape of a fish in the longitudinal direction, and

upper and lower plates that are curved in the same manner to the longitudinal backside respectively abdominal side, and with the abdominal sides facing each other.

An important optional embodiment is that by using the present invention, the light blinking influence can replace the displacement frames described in accordance with N0342294, that is to be pushed inwardly towards the fish in order to make the space tighter for the fish, and then retreated when the treatment is over and the fish is to be lead further on in the treatment line.

In the present invention, visible light is used, which is a form of electromagnetic radiation. Visible light creates the given visual impressions in a fish eye The visible spectrum is between the wavelengths of 380-750 nm.

In order to produce light blinks, one preferably use a light blinking source that may light and turn off the light in a given pattern or frequency. The turning on and off frequency can preferably be 1-20 blinks per second. Within this frequency the fish will comprehend the light blinks and be paralyzed thereof, and thus the fish is completely calm. The light is preferably a white light, even if light with different color tones - for example yellow-red-blue or green - may also be used.

It is especially preferred to use a stroboscope technology in order to provide light blinks. A stroboscope is an instrument that divides the light into light flashes (light blinks), as the stroboscope technology is well known and does not have to be described in detail herein.

In accordance with the invention the method and device is used for handling farmed fish, where the fish is lead trough a line in a counting device, where it is to be vaccinated, or tests are to be performed on said fish, fish lice is to be removed from the fish, or general transferal of the fish trough a transport system, as given by the use claim.

Description of the figures

Preferred embodiments of the present invention will now be described in more detail, with reference to the following figures wherein:

Figure 1 shows an example of treatment (fish lice removal/vaccination) of fish one by one in a collection of fish.

Figure 2 shows an enlarged drawing of the treatment chamber where one by one fish is kept still.

Figure 3 shows a collection of a large number of fish in a container or a pre chamber, where the fish is subjugated to light pulses in accordance with the invention in order to calm them down before being led into a narrower treatment pipe - one by one - as in figure 1.

Description of preferred embodiments of the invention

The invention will now be described in more detail with reference to figure 1 , which shows a situation where one by one fish in water 17 is led forward along a treatment lane in a treatment plant 10, and from a pre chamber 12 with more fish 16 to a narrowing pipe shaped treatment chamber 14 where there is only room to a single fish 16. In the treatment chamber 14 the one fish 16 is to stand as still as possible, by the aid of the present invention. It is apparent from figure 1 that right by the transition from the pre chamber 12 to the main treatment chamber 14 there is an extra channel 50 towards an optional free water body 60. Through the channel 50 there may be water current established by a pump from the chamber 12 and out into the water body 60. By the entrance there is a grating 52 that keeps fish from entering the channel 50. A suction pump is used to create a water current to the right. The purpose is to contribute a sufficient water current through the pre chamber 12 and to the treatment chamber 14 for fish to be pulled into the channel 12. A large number of fish 16 is illustrated in front of the chamber 14, while only a single fish is inside the treatment chamber itself as intended with the present invention. Thus an improved current is obtained, which is better able to lead the fish to the chamber 14. By revering the direction of the current through the pipe 50 one may achieve such an improved effect since the fish prefer to swim against the current.

The fish 16 may in be crowded together in the chamber 14 in advance by means of not shown mechanical crowding devices that will not be described herein, sine this is not strictly necessary since the light blinks alone can immobilize and paralyses the fish. The fish is initially fairly immobilized in the pipe, and one desire an even stronger immobilization by subjecting it to strong light blink in accordance with the present invention. The inside of the treatment chamber 14 is arranged with a number of light sources 20, placed with mutual distance around the entire inner wall of the pipe. The light sources can light up the fish with light beams as shown by 22 on the figures. The light sources 20 are, please see figure 2, connected to a not shown source of electricity 26 (K) (figure 2) by cable 22, as pulsator 24(S) is arranged in the wiring 22 in order to create the light blinks in accordance with the invention. When the number of light sources 20 is making blinking light with the before given frequency inside chamber 14, it is observed that the fish 16 becomes completely passive and paralyzed, as is desired in order to achieve an adequate treatment of the fish in chamber 1.

A grating 30 is shown at the intake end 15 of the chamber, and it is moved forward towards the right side when the fish is going to exit the chamber 14 after the treatment in chamber 14. In the outtake from pre chamber 12, where from one by one fish is taken and lead onwards to the right, there may also be placed on the inside light sources 20 around the inner circumference of chamber 14. The light sources in the two chambers may if desired be coordinated in order to make it easier to get the fish lead forward from the pre chamber 12 to the treatment chamber 14. By subjecting the fish to strong light flashes, there is also an effect on the fish when it glides forward in a dry channel to the shambles. The light blinks makes it so the fish calm down substantially, and becomes paralyzed and do not stress. This shows that the invention can be used and have an effect on fish in water and also on“shore”.

Figure 3 shows a closed container 40 where a larger amount of fish 16 is gathered. This could be the same chamber as the pre chamber 12. Placed around inside the chamber 40 there is mounted light sources 20 of the same type as used in figures 1 and 2. These light sources may bring forth light blinks as described. Practical trials have shown that the fish 16 in the body of water 17 became substantially calmer in their movements in the body of water 17 than in the absence of such light treatment. This container may be the pre chamber 12 as described in relation to figures 1 and 2.

Practical experiments has shown that one may switch between the usual permanent lightening 22 from the light sources 20 and blinking (strobe) light in order to calm the fish down, as the normal parameters of the lights may easily be changed to strobe light when it is desired to calm the fish. There does not need to be different or special frequencies or colors when one use the blinking lights, other than that it should be adapted to the number of fishes 16 in the body of water 17, which depends on how frequent the lights 20 are placed on the inner wall, and how crowded the fish 16 are in the body of water 17, etc. How crowded the fish are, and how clear the water is, is of importance. The more muddy the water is, the more crowded the fish is, the stronger the light needs to be in order to achieve the desired effect.

Generally, the number of light sources inside is adapted to the hollow body’s volume, the number of fish in said volume, as well as the visibility (clarity) of the water the fish is in. An increasing number of light sources is used in correlation with the increase of water volume, number of fish, as well as reduced visibility (more mud) in the water.

In addition, the light sources (the lamps) light strength will be increased in correlation with the increase in water volume, the number of fish in the tank 12, as well as reduced visibility in the water. The more particulates and mud there are in the water, the visibility will be reduced, and a stronger light source is needed.

In the present invention it is thus shown that fish that is exposed to light blinks (strobe light) is paralyzed to stay still when it is touched. This can be used for all kinds of treatments of fish, in slaughtering lines for example, for calming the fish down, and otherwise in situations where there is a need to calm the fish down in some setting.

The fish must be confined when the strobe lights are turned on. Normally they will swim away from strobe lights.

Claims

1. Method of temporarily immobilizing fish, characterized in that the fish is exposed to blinking light from one ore more light sources while confined.

2. Method in accordance with claim 1 , characterized by that a blinking lights source is used that can turn the light on and off in a given pattern or frequency, preferably a blinking frequency of 1-20 blinks per second.

3. Method in accordance with one of the previous claims, characterized by that the fish is treated in a feed line shaped as a hollow body shaped compartment where the inside of the body is arranged with a number of light sources that can influence the fish with light blinks.

4. Method in accordance with one of the previous claims, characterized by that the used number of inside light sources is adapted to the volume of the hollow body, number of fish in said volume, and the visibility of the water the fish is located in.

5. Method in accordance with claim 4, characterized by the use of an increasing number of light sources in correlation with the increase in water volume, the number of fish, and the reduction in visibility in the water, and/or the strength of light from the light source is increased in correlation with the increase in water volume, the number of fish, and the reduction in visibility in the water.

6. Method in accordance with claim 3, characterized by the hollow body being a pipe wherein fish, one by one, is lead to a station where they are subjected to light blinks from the light sources therein in order to immobilize the fish.

7. Method in accordance with claim 6, characterized by that the fish residence volume is in advance constricted by mechanical means (with plates that can be moved in and out) in the pipe, before the blinking light treatment is started.

8. Method in accordance with claim 3, characterized by that the hollow body is a pre chamber or a tank with a number of fish, where the inside of the tank is arranged with a number of light sources, both along side walls, the bottom surface, and ceiling.

9. Method in accordance with claim 8, characterized by that the used pre chamber (12) extends over into said pipe (14) as the pre chamber (12) contains fish and also comprises a number of blinking light sources (20) in the wall parts, bottom and ceiling parts, in order to prepare the fish, i.e. to calm the fish down, before transferal to the pipe (14), by a suitable activation and deactivation of the light sources (20) in the pre chamber (12).

10. Method in accordance with one of the previous claims, characterized by the use of white light, or a light with yellow-red-blue-green color tone.

11. Method in accordance with one of the previous claims, characterized by the use of a stroboscope technology in order to produce the blinking light, where the stroboscope divides up the light into light blinks.

12. Device for immobilizing fish that are kept in a closed container or being lead along a treatment line toward treatment, characterized by the inside of the container and treatment line comprise a number of light sources that can subject the fish to flashes of light.

13. Device in accordance with claim 12, characterized by the placement of the sources of light on the inside of the container/treatment line which is a pipe, a pre chamber, or a tank.

14. Device in accordance with claim 12 or 13, characterized by the light sources comprising stroboscopes in order to produce blinking light, where the stroboscope is dividing the light up into blinks of light.

15. Use of the method and/or device in accordance with the previous claims for handling farmed fish, where the fish is lead along a line in a counting device, is going to be vaccinated, or the fish is to be tested, fish lice is to be removed from the fish, or general transferal of the fish through a transport system.