Scientists often rely on animal models for scientific research. Both terrestrial and aquatic animals are used as models for scientific research. One prominent aquatic animal model used by many scientists for various experiments is the zebrafish (Danio rerio, a.k.a. Brachydanio rerio). For example, zebrafish are used for modeling human disease, drug discovery, cancer research, genetics research, regenerative medicine, chemical screening, and toxicology. While zebrafish replication is considerably faster than many other animal models, current methodologies and breeding equipment used for zebrafish replication are insufficient to meet the demands of scientific research. In particular, scientists often need large numbers of developmentally synchronized zebrafish embryos within short periods of time to facilitate their research. Therefore, improved breeding equipment is needed to increase the rate and developmental uniformity of aquatic animal embryo production.
Some embodiments provide a spawner designed to hold water and at least one aquatic animal. The spawner includes a vessel and a platform disposed within the vessel. The platform includes a raised point, a floor that extends downwardly at an angle from the raised point to a peripheral edge, and a plurality of vertical walls defining at least one cubby.
Other embodiments provide a spawner having a vessel and a platform disposed within the vessel. The vessel has an internal volume shaped such that when water within the vessel is lowered from a higher holding level to a shallow spawning level during a spawning event, the cross sectional area of the vessel measured at the air-water interface is reduced to crowd fish disposed within the water into a higher animal density per unit area.
Additional embodiments provide for a method of producing a plurality of aquatic animal embryos. A vessel, an angled platform disposed within the vessel, and a valve are provided. The vessel is filled with a liquid such that the vessel is substantially full and defines a holding level of water. At least one male aquatic animal and at least one female aquatic animal are provided into the vessel. The holding level of water in the vessel is decreased. The valve is closed when the water level has reached a spawning level to facilitate a spawning event between the at least one male aquatic animal and at least one female aquatic animal.
Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items.
The following discussion is presented to enable a person skilled in the art to make and use embodiments of the invention. Various modifications to the illustrated embodiments will be readily apparent to those skilled in the art, and the generic principles herein can be applied to other embodiments and applications without departing from embodiments of the invention. Thus, embodiments of the invention are not intended to be limited to embodiments shown, but are to be accorded the widest scope consistent with the principles and features disclosed herein. The following detailed description is to be read with reference to the figures, in which, like elements in different figures have like reference numerals. The figures, which are not necessarily to scale, depict selected embodiments and are not intended to limit the scope of embodiments of the invention. Skilled artisans will recognize the examples provided herein have many useful alternatives and fall within the scope of embodiments of the invention.
The present disclosure is directed at improved breeding equipment for the production of fish embryos from various fish, including freshwater and marine fish, and may be used for breeding of many other aquatic species. For example, various types of fish may be used with the breeding equipment of this disclosure and include, for example, zebrafish (Danio rerio, a.k.a. Brachydanio rerio), rainbow trout (Oncorhynchus mykiss) and other salmonids including and brook charr (Salvelinus fontinalis), coho salmon (O. kisutch), sockeye salmon (O. nerka), and Atlantic salmon (Salmo salar). Additionally, other types of fish contemplated include the sheepshead minnow (Cyprinodon variegatus), silversides (Menidia beryllina and M. menidia), the fathead minnow (Pimephales promelas), and the Japanese medaka (Oryzias latipes). Other species include catfish such as channel catfish (Ictalurus punctatus), brown bullheads (Ameiurus nebulosus), sunfish (Mola mola), bluegill (Lepomis macrochirus), tilapia (Oreochromis mossambicus), Amazon molly (Poecilia formosa), and American eels (Anguilla rostrata). Additional species include goldfish (Carassius auratus) and koi (Cyprinus carpio). It is also envisioned that other types of aquatic species may be bred in the disclosed spawner.
A cylindrical wall defines an aperture 142 that is disposed at a lower end 140 of the vessel 102 and is adapted to provide an outlet to drain and/or fill the vessel 102. A valve 144 may be connected to the aperture 142 to permit selective drainage from the vessel 102 (or filling) upon opening of the valve 144 by turning a valve handle 146 or similar mechanism. In one embodiment, the valve 144 is provided as a ¾″ single entry socket PVC ball valve (Spears® Manufacturing Company, Sylmar, Calif.).
The vessel 102 may further include one or more ports 148 to facilitate adding, maintaining, and/or draining water at a desired level. In the illustrated example, the ports 148 are circular and extend entirely through the sidewall of the upper chamber 104 adjacent a top edge 130 of the vessel 102. When the level of liquid (e.g., water) in the vessel 102 is too high, excess water may drain through the ports 148. In some embodiments, the ports 148 may be selectively closable or omitted entirely to allow for the liquid level in the vessel 102 to extend upwardly past the ports 148 adjacent the top edge 130. In other embodiments, a valve or other mechanism may be provided in a port 148 and in communication with a water source to assist in filling the vessel 102.
The spawner 100 also includes the platform 108, which is best shown in
The platform 108 is defined by a floor 150 having a top surface 120 that surrounds and extends downwardly at an angle from the raised point 112 to the peripheral edge 152 to create a generally conical or pyramidal shape, though other shapes are contemplated, such as a wedge. The floor 150 is defined by a plurality of flanges that includes gaps 158 large enough to permit embryos, larvae or fry to pass through to the lower chamber 106, but small enough to prevent adult fish from passing through to the lower chamber 106. In this way, the floor 150 of the platform 108 is selectively permeable to fish embryos, larvae, and/or fry.
A plurality of vertical and triangular walls 154 protrude upwardly from the floor 150 of the platform 108 to the raised point 112 and connect at the stem 110 to create wedge-shaped spaces or cubbies 156 therebetween. There may be any number of walls 154, such as 2, 3, 4, 5, 6, 8, 10, or more to create any number of cubbies 156. In some embodiments, the walls 154 protrude outwardly from the stem 110 and terminate prior to reaching the peripheral edge 152 of the platform 108. In the embodiment depicted, the walls 154 protrude outwardly from the stem 110 about 75% of the distance between the stem 110 and the peripheral edge 152.
The platform 108 is designed to interact with the narrowing inner surface 114 of the vessel 102 such that the peripheral edge 152 of the platform 108 is shaped to closely fit and contact the inner surface 114 of the vessel 102. This interaction prevents adult fish from swimming into the lower chamber 106 from the upper chamber 104 (or vice versa). In this way, the spawner 100 prevents predation of fish embryos, larvae or fry by adult fish after spawning because embryos released in the upper chamber 104 pass through the platform 108 into the lower chamber 106. Other methods of suspending the platform 108 to create the upper and lower chambers 104,106 are envisioned. For example, one or more structural features 116 (see
The platform 108 may further include one or more supports 160 that promote structural integrity of the platform 108, for example, by making the platform 108 more rigid, and further to help securely seat the platform adjacent the inner surface 114 of the vessel 102. In the embodiment depicted, the supports 160 are elongate flanges that are provided on an underside of the floor 150 of the platform 108 and are spaced apart from each other.
Referring again to
The divider 118 is designed to enable a user to divide the upper chamber 104 into separate chambers, for example, for separation of adult fish by sex (e.g., male and female). The divider 118 is further designed for easy removal from the upper chamber 104 by simply lifting the divider 118 out of the upper chamber 104 and off the stem 110 to allow fish disposed in the upper chamber 104 on either side of the divider 118 to mix.
In a further embodiment shown in
It is also envisioned that the spawner may be configured in additional ways and/or include different parts. As shown in
Similar to the previous embodiment, the vessel 302 includes a widened upper chamber 304 and an inwardly tapering lower chamber 306. The upper chamber 304 includes a cylindrical sidewall that defines an opening designed to receive the lid 328. The sidewall of the upper chamber 304 may include one or more ports 348 to facilitate maintaining water at a holding level. In one embodiment, a water supply valve 378 is fitted into the port 348 and is in communication with a water source that facilitates water being added to the vessel 302. It is also envisioned that the water supply valve 378 can be, or can include, a spigot, a spout, a hose connection, or the like. The water supply valve 378 may also include an elastic and/or plastic gasket (not shown), socket, threads, or may be physically soldered, welded, or epoxied into the port 348. In some embodiments, the port 348 and water supply valve 378 may be provided in a different location on the vessel 302, such as, for example, on the lower chamber 306.
The lower chamber 306 is substantially funnel shaped and tapers inwardly until terminating at a lower end 340. In one embodiment, the angle of the tapered sidewalls of the lower chamber 106 of the vessel 102 is between about 40° and about 70°. In another embodiment, the angle of the tapered sidewalls of the lower chamber 106 of the vessel 102 is between about 55° and about 65°, and more specifically, is about 60°. The lower end 340 of the vessel 302 includes a wall defining a cylindrical aperture 342 that is designed to interact with one or more components that facilitate collection of embryos and/or maintaining, filling, and/or emptying the liquid level of the spawner 300, as described in more detail below. For example, in one embodiment, the aperture 342 is configured to interact with a valve 344 having a valve handle 346 that allows for liquid and/or embryos to exit the vessel 302. In one embodiment, the valve 144 is provided as a ¾″ single entry socket PVC ball valve (Spears® Manufacturing Company, Sylmar, Calif.).
The platform 308 also includes a floor 350 that surrounds and extends downwardly at an angle from the raised point 312 to a peripheral edge 352. A plurality of vertical walls 354 extend from the floor 350 of the platform 308 to the raised point 312, connecting with the stem 310 to create wedge-shaped spaces or cubbies 356 therebetween. The platform may have any number of walls 354, such as 2, 3, 4, 5, 6, 8, 10, or more to create any number of cubbies 356. In one embodiment, there are four triangular vertical walls 354, spaced equidistantly on the platform 308. Similar to the embodiment shown in
The platform 308 may be inserted into the vessel 302 to securely rest adjacent the inner surface 314 of the vessel to create a selective barrier or boundary between the upper 304 and lower 306 chambers. In one embodiment, the inner surface 314 of the vessel 302 is about 9.5 cm wide and is tapered at an angle of about 10° to create an angled surface configured to hold the platform 308. Other methods of suspending or supporting the platform 308 to create the upper 304 and lower 306 chambers are envisioned. For example, one or more structural features 316 may be included on the inner surface 314 and/or on the platform 308 including, for example, an elastic and/or plastic gasket, a ledge, a bracket, a detent, threads or other means known in the art.
As shown in
The divider 318 is designed to enable a user to divide the upper chamber 304 into separate chambers, for example, for separation of adult fish by sex. The lower edge 324 of the divider 318 is angled to correspond to and complement the angle of the floor 350 of the platform 308. For example, in one embodiment, the angle A of the lower edge 324 of the divider 318 is about 135°. As such, the divider 318 is shaped to be inserted into the upper chamber 304 and rest on a top surface 320 of the platform 308 to divide the upper chamber 304 into two lateral volumes. When positioned, the lower edge 324 of the divider 318 is designed to contact the top surface 320 of the platform 308 such that no fish are permitted to swim from one side of the divider 318 to the other side of the divider 318. The width of the divider 318 is designed to correspond to the width of the upper chamber 304 of the vessel 302 such that no fish are permitted to swim over or around the divider. In one embodiment, the width of the interior of the upper chamber 304 of the vessel 302 and the width of the divider 318 are substantially the same. In one specific embodiment, the width of the interior of the upper chamber 304 of the vessel 302 is about 35 cm and the width of the divider 318 is about 35 cm.
An elevated ridge 372 protrudes upwardly from the upper edge 326 of the divider 318 and is provided to interact with the removable lid 328, as discussed in more detail below. The divider 318 is designed for easy removal from the upper chamber 304 by lifting the divider 218 out of the upper chamber 304 and off the stem 310 to allow fish disposed in the upper chamber 304 on either side of the divider 318 to mix.
The middle section 328a of the lid 328 includes a central elongate slit 332 that is shaped to accommodate the elevated ridge 372 of the divider 318. When the lid 328 is positioned on the vessel 302, portions of the lid 328 may contact the top edge 330 of the vessel 302 and the elevated ridge 372 of the divider 318 passes through and is seated within the slit 332 of the middle section 328a of the lid 328. In this way, the lid 328 may be releasably secured to the divider 318. The interface between the slit 332 of the lid 328 and the elevated ridge 372 of the divider 318 is configured to stabilize the divider 318 laterally (i.e., vertical orientation) in the vessel 302 to prevent the divider 318 from tipping or tilting. In some embodiments, the lid 328 may be removable from the divider 318 such that the lid 328 may be removed from the vessel 302 without removing the divider 318. In other embodiments, removal of the lid 328 may cause the divider 318 to also be removed from the vessel 302. The lid 328 also may be secured to the vessel 302 in any number of ways known in the art.
As shown in
The interior surface of each of the opposing vertical walls 365 includes a shelf bracket 402 that extends across the entirety of the surface. The shelf brackets 402 are designed to support a shelf 400 that is provided in the form of a flat wall 401 with a circular opening 404. The shelf 400 is designed to be positioned below the valve 344 and/or located adjacent a bottom section of the vessel 302. In some embodiments, the shelf 400 is releasably secured to the shelf brackets 402. In other embodiments, the shelf 400 may be provided as an integral part of the support 362.
The opening 404 in the shelf 400 is designed to support the catch funnel 410, which, in turn, is designed to support the egg strainer 420. The catch funnel 410 may be conically shaped with an open top and a narrower aperture 414 at a lower end 412 (See
The shelf 400 is also designed to support the egg strainer 420. The egg strainer 420 is provided in the form of a cup 426 with a handle 422 protruding outwardly from an upper edge 428 of the cup 426. In one embodiment, the handle 422 of the egg strainer 420 may have a small aperture 424 to allow the egg strainer 420 to be releasably secured to the shelf 400, such as by a screw or hook (not shown). In another embodiment, the handle 422 of the egg strainer 420 may be provided as a rigid wire frame. The egg strainer 420 may optionally have a detent or knob (not shown) opposite the handle 422 such that the egg strainer 420 can be suspended over the catch funnel 410. In some embodiments, the egg strainer 420 rests on the interior surface of the catch funnel 410. In other embodiments, the egg strainer 420 may be positioned above the catch funnel 410 and supported only by the shelf 400. In some embodiments, the egg strainer 420 is made of metal, and in one specific embodiment, the egg strainer 420 is made of stainless steel.
The cup 426 is designed to be a permeable strainer and may be made from any material, such as metal, glass, plastic, composite, and combinations thereof. The cup 426 includes a plurality of pores, holes, slits, apertures, mesh, weaving, and/or combinations thereof, which may be sized in any manner that enables retention of embryos, larvae, or fry in the cup 426 of the egg strainer 420, but is permeable to liquids or solutions. In some embodiments, the cup 426 is made of fine mesh stainless steel, and in one specific embodiment, the egg strainer 420 is a stainless steel fine mesh strainer made by Procizion.
In this configuration, the shelf 400 is situated adjacent a lower end of the support 362 and below the valve 344 such that the effluent from the valve 344 can be caught and passed through the egg strainer 420 to the catch funnel 410. At the same time, embryos, larvae, or fry are retained in the cup 426 of the egg strainer 420. When the spawning process is finished, the egg strainer 420 may be detached from the shelf 400 and/or catch funnel 410 and removed to transport the embryos, larvae, or fry into a different container.
As best seen in
In use, the pipe junction 452 may be configured as to permit selective drainage from the vessel 302 upon opening the release valve 344 by turning the valve handle 346. In this way, fluid and/or embryos may be permitted to flow out of the vessel 302, through the valve 344, and to the egg strainer 420 to the catch funnel 410. Additionally, the pipe junction 452 and the plumbing apparatus 450 may be configured to remove water from the vessel 302 of the spawner 300 by opening control valve 460. In one embodiment, the upper rung of a double H standpipe configuration of the plumbing apparatus 450 dictates the water level within the vessel 302 of the spawner 300. In one embodiment, the plumbing apparatus 450 may be used in a flow through or recirculation configuration in which water continuously flows into, through and out of the water supply valve 378, vessel 302, and plumbing apparatus 450, maintaining the water in the vessel 302 at the holding level H.
To provoke a spawning event, the spawner 300 (or spawner 100) may be set up and used in the following manner. The vessel 302 of the spawner 300 may be suspended in the support 362. The plumbing apparatus 450 may be connected to the vessel 302 and the support 362 as described above. The water supply valve 378 may also be connected to a fluid (water) source. The platform 308 may be positioned within the vessel 302 and the divider 318 may be inserted through the top of the vessel 302 until contacting and/or being secured to the platform 308 via the notch 322/stem 310 interaction. The shelf 400 is inserted into the shelf brackets 402 and the catch funnel 410 is supported by the shelf via the opening 404 (or other mechanism). The egg strainer 420 is positioned within the catch funnel 410 below the valve 344 of the vessel 302.
Once the spawner 300 is configured, water or another fluid may be added to the spawner 300 via the water supply valve 378 in the port 348 and/or through adding water through the top of the vessel 302 with the lid 328 removed. To add water to the vessel 302, the water source is turned on, the water supply valve 378 is configured in an open position, the release valve 344 is in a closed position, and the control valve 460 is in the closed position. In one embodiment, the water level will automatically be maintained at the holding level via the external double H standpipe configuration of the plumbing apparatus 450. Once the vessel 302 has enough fluid to be at the holding level H, as depicted in
After the male and female aquatic species are positioned within the vessel 302, the divider 318 may be removed and the water may be lowered to the spawning level S by opening the control valve 460. In one embodiment, the water level is automatically maintained at the spawning level S by the double H standpipe configuration of the plumbing apparatus 450 when the control valve 460 is in the open position. Lowering the water to the spawning level S causes the male and female aquatic species to interact in a spawning event. Due to the mating behavior of many various aquatic species, the male aquatic species chase or drive the female aquatic species into shallow water where mating may take place (arrow F). However, unless there is some obstruction hindering lateral movement of the female, the female may be able to escape to deeper water and avoid spawning. Here, the cubbies 356 serve to funnel fish into a shallower and narrower space within the walls 354 on either side, closing off any chance of lateral escape.
During the spawning event, embryos, larvae, or fry pass through the floor 350 of the platform 308 and are collected in the lower chamber 306. Once the spawning event is finished, the valve 344 may be opened via the handle 346 to allow the fluid and embryos in the lower chamber 306 to flow into the egg strainer 420. The egg strainer 420 collects the embryos and allows fluid to pass through to the catch funnel 410. Fluid flows through the catch funnel 410 and exits the system via the pipe 418.
After the spawning event, the water level may be raised again to the original holding level H, or to a new, different holding level. For example, the water level may be raised to the original holding level H by closing the control valve 460 on the double H standpipe configuration of the plumbing apparatus 450. The male and female aquatic species may be separated and/or removed from the spawner 300 and the procedure repeated.
The vessels, platforms, dividers, and/or lids may be made from a variety of materials, such as, for example, metal, glass, plastid, composites, and combinations thereof. In one embodiment, the vessels 102, 302 and the lids 128, 328 are transparent or at least translucent, and the platforms 108, 308 and the dividers 118,318 are opaque. However, any variations in light permeability and material colors are contemplated.
As discussed throughout, the spawner 100, 300 may be used to produce thousands of developmentally synchronized zebrafish embryos within a relatively short window of time, such as, from about 15 min to several hours, by taking adult fish placed in the upper chamber 104 from a deeper water, holding level (arrow H) to a spawning level (arrow S) (see
In addition to crowding fish with respect to area, the spawner 100, 300 is unique in that the platform 108, 308 provides one or more cubbies 156, 356. Typical zebrafish mating behavior includes for the male fish to chase or drive female fish into shallow water where mating may take place (arrow F). However, unless there is some obstruction hindering lateral movement of the female, the female may be able to escape to deeper water and avoid spawning. Here, the cubbies 156, 356 serve to funnel fish into a shallower and narrower space within the walls 154, 354 on either side, closing off any chance of lateral escape. Therefore, increased incidences of successful spawning are believed to occur with the spawner 100, 300, which lead to increased numbers of embryos produced. This approach contrasts with existing technologies for the mass production of zebrafish embryos that allow fish to escape pursuit into the shallower areas during the spawning phase if they so choose by swimming laterally.
The vessel may also be of any size and may have any shape, such as rectangular, square, conical, cylindrical, triangular, and combinations thereof. In one embodiment (not shown), the vessel may be made of separate pieces that are joined together by an adhesive, a gasket, combinations thereof, and the like. The platform, divider, and the lid may be sized to the vessel in any manner that enables function of the spawner as envisioned herein.
The following examples illustrate use of the spawner 100, 300 as described above.
A spawner was set-up with a platform and a divider placed therein, with the valve closed. The spawner was filled with water to the holding water level (about 14 L). Water was recirculated at a rate of about 0.5 L/min within the spawner by means of a recirculating siphon, with outflow on one side of the divider and inflow in the opposite side. Initially, fish were placed in the upper chamber of the spawner with females on outflow side and males on incoming water side. The fish used were zebrafish from 5D Tropical, Inc. (Plant City, Fla.; “5D”) and a strain of zebrafish developed at Duke University, Durham, N.C. USA that originally came from Ekkwill Waterlife Resources (Ruskin, Fla.; “EK”). Different groups of fish were identified by source and number, such as 5D1 and 5D2, which indicate groups 1 and 2 of fish from 5D.
The spawning trial procedure was as follows: the correct numbers of fish were stocked on each side of the divider, including 24 females and 6 males (sex ratio of 4:1 females to males) in the evening of day 1; on the morning of day 2, the divider was removed and the fish comingled for 5 minutes; the flow of water was shut off; water was drained to spawning level (6 L) so that about 1 cm of the spawning platform was above the water level with the drained water collected and any embryos present set aside; the fish were allowed to spawn for 3 hours; afterwards, water flow was returned, and the vessel was filled to holding level (14 L); the flow was again turned off and water drained to the spawning level to collect the embryos; and the volume of embryos produced was measured (using an estimate of about 607 embryos/ml) and the number of embryos calculated pre-level drop and post-level drop.
Results of embryo production based on the above procedure are listed below in Table No. 1.
As can be seen in Table No. 1, far more embryos were produced after the water level drop in the spawner than before. These data indicate the effectiveness of the spawner design and illustrate that very large numbers of developmentally synchronized zebrafish embryos may be produced in a short period of time. For example, at least about 600 to about 800 embryos per hour may be generated per spawner of the size used.
An additional trial was performed using the same procedure as described above with a sex ratio of 2 females to 1 male and a total of 36 AB strain zebrafish, including 24 females and 12 males, all born on the same day. The total embryo production is shown in Table No. 2.
It will be appreciated by those skilled in the art that while the invention has been described above in connection with particular embodiments and examples, the invention is not necessarily so limited, and that numerous other embodiments, examples, uses, modifications and departures from the embodiments, examples and uses are intended to be encompassed by the claims attached hereto. The entire disclosure of each patent and publication cited herein is incorporated by reference, as if each such patent or publication were individually incorporated by reference herein. Various features and advantages of the invention are set forth in the following claims.
This application claims priority under 35 U.S.C. §119 to U.S. Provisional Patent Application No. 62/115,031 filed on Feb. 11, 2015, the entire contents of which is incorporated herein by reference.
Number | Date | Country | |
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62115031 | Feb 2015 | US |