WO2002035924A2 - A complete non-surgical embryo recovery and transfer system - Google Patents

Abstract

An apparatus and method for the non-surgical removal of embryos in swine and for the transfer and placement of the embryos into a surrogate mother sow. An introducer and speculum are used and are introduced through the cervix of the sow. The tip of the introducer vibrates at a high frequency those vibrations are transmitted to the distal end of a specially contoured tip. A catheter apparatus is used after gaining entry to the uterus, and the catheter apparatus includes coaxially aligned inner and outer catheters. The outer catheter has a pair of individually inflatable and deflatable cuffs and an ingress port between the cuffs and an outlet for the discharge of fluid. Continued discharge of the flushing fluid from the distal end of the inner catheter causes a flushing of the embryos from the uterine horn to the collection chamber. The embryos are separated from the flushing fluid and subjected to a standard protocol in order to provide pathogen free embryos for transfer and international distribution.

Description

SPECIALIZED UNITS FOR IMPROVED SWINE THROUGH THE USE OF SUIS™ - A COMPLETE NON SURGICAL EMBRYO RECOVERY AND TRANSFER SYSTEM

Background of the Invention

This invention relates to an apparatus and method for the collection and transfer of embryos in litter bearing animals and most particularly swine.

In general, there is currently in use today, embryo collection and transfer in various animals including cows, horses. The process is successfully used both to improve and maximize the production of enhanced genetic traits expressed by the parents. It also allows for ongoing performance and production while propagation of the offspring is ongoing. Embryo transfers can be used in controlling and preventing the spread of diseases in such animals.

In the case of swine, however the removal of the embryos from a sow or gilt and the subsequent transfer of those embryos to a surrogate mother is a complicated procedure involving, typically anesthetic and surgery. Hence the procedure is one that is not readily undertaken on a commercial basis but is reserved primarily for research purposes or in extreme cases where a disease has destroyed an entire herd or farm operation. This limited and selective use of surgical recoveries and transfers has truncated the true potential that is available to the swine industry by making the procedure too expensive, requiring large capital outlays and necessitating the strict use of professional veterinary skills.

The difficulty stems from the differing reproductive organs of the pig. In other animals, the removal of embryos is a fairly straightforward process. It is accomplished by the rectal manipulation of an instrument which is passed through the cervix of the animal in such a manner that a single catheter can enter the uterus where the embryos are located thus permitting their straight forward recovery. With swine, however, the procedure is not that simple. The cervix of the sow is considerably longer, i.e. about 4-8 inches in length and is extremely tight with various interdigitating folds along its length. Thus, it is not possible to use the same instruments that are commonly employed with horses or cows to carry out the removal of the embryos from a sow.

Accordingly, there is an experimental non-surgical procedure that has been used which involves a transvaginal collection technique. It is accomplished by passing a cannula and stylet around the cervix, bypassing this anatomical obstruction, however the procedure has proven to be both difficult and traumatic to the sow. Additionally, it is fraught with low numbers of embryos and causes considerable scarring after repeated collections. Yet a second methodology is to perform surgery on the very juvenile female piglet and shorten the uterine horns by removing large sections thereby making the embryo recovery process easier, in theory, if in the adult pig one could circumnavigate the cervix. Both methods have not proven effective and are not practiced by the industry.

Thus, the only current and viable means of removing embryos from sows is through the use of invasive surgery and that operation requires an operating suite, anesthetic equipment for administering anesthesia to the sow and a veterinarian, with assistants, which must perform the operation on the animal. As such, the operation cannot be performed on the farm or other sow locations since a surgical suite is not normally present. Thus the sow must be transported to the surgical site of the veterinarian where the procedure can be perfonned. The operation is quite onerous, labour intensive, very expensive and is, therefore, not widely practiced anywhere in the world. As such, the swine population are deprived of benefits provided by embryo collection and transfer as a means of establishing improved genetic makeup for existing herds or for the control and prevention of diseases within swine facilities.

When used for the prevention of disease, the procedure of embryo collection and transfer is a very effective method of cleaning up a herd and would be extremely advantageous in swine operations where a disease has decimated the entire herd of animals and there is no other means to preserve the genetic lines. The disease prevention and control involves the removal of the embryos from the sow at about the fourth or fifth day after their conception when the embryo is typically at the 4-8 cell stage. At that point, the embryo is surrounded by a protective shell, known as the zona pellucida and the disease causing pathogens cannot enter the cells due to the protective shell but instead are attached to the external area of that shell. Upon collection of the embryos from the uterine horns, the embryos are subjected to a cleansing process that is carried out in accordance with a published protocol of the International Embryo Transfer Society (IETS). The recovered embryos are washed several times, isolated, then screened and graded for transfer suitability. The undesirable embryos are removed and the remaining embryos are further subjected to the prescribed IETS enzyme treatment where the pathogens and their associated antigens are removed from the outer surface of the shell. Thus embryos, after the treatment, are free from all known disease causing pathogens and the embryos can now be transferred to a disease free surrogate mother or to a specific pathogen free surrogate in order to be carried forward to birth of the piglets approximately 150 days later.

The threat of a contagious disease entering and annihilating the remaining herd is so serious that even when the surgical operation is performed, the owner generally does not want the harvested sow returned to the herd for fear that the animal has picked up some disease bearing pathogen during the embryo removal process or at the location of the veterinarian's surgical suite.

Therefore in the present situation, using the techniques currently available, pigs are not generally harvested for the embryos and thus the optimum benefits available through the creation and use of specialized swine units is 'rate limiting'. The state of the industry as it exists today is limited on the male side by the genetic lines that compliment the dames side of the genetic pool for birth weight, lean index, feed conversion etc. Also many of the diseases that are enzootic today are directly linked to the spread of infected semen by both natural and artificial breeding. The current practice by definition forces the mother to contribute one half the genes to the offspring. Hence compromises in gene selection must be made so she can deliver the piglets without a dystocia or caesarian section, be a good mother and have the indexing and weight gains acceptable to the industry. Introducing and improving lines of breeding stock is a slow and very risky part of the business today. The single reason embryos are not used today is because the industry could never be supplied with sufficient numbers by surgical techniques to even begin such a process not to mention the prohibitive cost for such a program.

The importance of embryo transfer in swine is, however, a very important and necessary need to both people and the industry. When done on a commercial basis it allows for purpose specific pigs and herds to be developed that are completely independent of each other. In addition to disease prevention, there is a need to use the process of embryo transfer in order to improve the overall genetic traits of the swine herd and to improve the production of good meat producing swine. There are certain sows that, due to their genetic makeup, are excellent mothers, that is, they have a wide pelvic inlet and a prolific uterus backed up by a large mammary system to produce a plentiful supply of milk for the suckling piglets, however, that sow in and of itself is not a good candidate for meat, production. On the other hand, there are various strains of pigs that are excellent for meat production, however their mothering attributes are inadequate, that is, the mothers have an inadequate size in the reproductive tract and the piglets being born are often unable to pass through the birth canal or, once bom, the mother is unable to provide sufficient nourishment to the suckling pigs. The problem of the two seeming anomalies is due to the manner in which linked genetic traits of the animal are transferred and no amount of cross or interbreeding has been able to solve the problem to date. Even if some gains were made they would be small and take many years for each herd to do it on its own. There still would be the ongoing risks and problems associated with endemic diseases in the herds.

The solution to the problem again lies in the procedure of embryo harvesting and transfer to the surrogate mother. It is important to note that genetic traits are transferred from the natural mother-donor to the embryo and, correspondingly, there is no genetic link between the surrogate mother and the piglet she delivers. Thus, the removal of the embryo from the natural mother can carry the desired genetic traits to the piglet by the use of a surrogate mother without interference with the genetic traits of that surrogate mother and the surrogate sow can be used simply for its inherently good mothering characteristics. The ultimate result, therefore, is the production of disease free, genetically specific superior swine. By greatly enhancing the productivity of meat producing pigs one automatically provides an increased supply of the meat product for human consumption.

Thus, the only method of solving that urgent problem and to achieve the best of both worlds, that is to make use of the good mothering characteristics of the mothering pigs and to produce piglets that are capable of growing rapidly and efficiently based upon the growth rate per amount of feed provided to those piglets, is through the process of embryo transfer. With this process, the whole methodology of selecting and developing the highest genetic trait for a specific unit of production is faster through use of line breeding and less risky because the surrogate is not a genetic contributor.

The embryos from excellent meat producing pigs can be transplanted into the surrogate, good mothering pigs and achieve the desired results immediately without extensive trials, waiting and discarding of undesirable progeny. Moreover the purpose specific traits can be designed for any number of end purposes not least of which is maximum birth weight, weaning weight, feed conversion ratios and shortest days to market with a significantly higher index for lean meat.

The major impediment goes back to the previously described problem of the cost and difficulty of carrying out the removal of embryos from the sow and the reintroduction of those embryos into surrogate mothers due to the inherent complications of the surgical operation currently employed in swine. Thus the limiting process for the overall removal and replacement process lies in the expertise required for the embryo removal that is time consuming and expensive and makes the commercial supply of embryos economically prohibitive and impracticable even if surrogate recipients and high production feeder pigs were developed.

It would, therefore, be advantageous if there were a novel method and apparatus that could be used by a lay person to remove the embryos from a sow easily, without risk or damage to the donor and without the complications or expense of undergoing a surgical operation by skilled personnel. If this method was economical and could be afforded by the owner of the herd then it would improve that herd's efficiencies and also provide a means to disseminate their own genetics without the risk of spreading any known diseases. Summary of the Invention

Thus, in accordance with the present invention, there is provided a method and apparatus for the removal of embryos from a donor sow and for the transfer of the embryos into a surrogate mother sow, all without the need for a surgical procedure or the need to have a skilled veterinarian carry out the procedure. With the present invention, the embryos can be removed easily and effectively from a sow by any lay person after some basic instructions and the procedure can be carried out in situ where the herd is located and thus avoid the need to transport the sow to a remote facility. Accordingly, the overall process and apparatus of the present invention can be simplified and used by the owner of the swine herd and the embryos removed for transfer and placement into the surrogate mother in any location in the world.

In the present invention, there is a specially constructed introducer that fits within a speculum and the introducer and speculum combined is introduced into the cervix of the sow to the uterine body. By use of the speculum containing the introducer of the present invention, the cervix path that is normally very difficult to penetrate on a sow, can be easily negotiated along and through the cervix along with the speculum. After the speculum and introducer have reached the uterine body, the introducer is removed and the speculum maintained in that position. The present introducer utilizes a specially configured profile tip that can penetrate the cervix of the sow and with the additional employment of a high frequency axial oscillation or vibration that is transmitted to the tip. This high frequency vibration is designed to aid in the relaxation of the fibrous tissue which will assist in penetration and successful negotiation of the entire cervix of the sow. In the preferred embodiment the axial oscillation is an ultrasonic frequency and may be generated by a piezoelectric crystal that is excited by an electric field. The use of the axially oscillating introducer allows the speculum to be positioned directly through the penetration of the cervix of the sow such that the speculum can be placed in a position with its distal opening at the entrance to the uterine horn for access to the embryo contained within the uterine horn of the sow. A specially designed catheter apparatus then can be introduced through the internal bore of the speculum after removal of the introducer. The catheter apparatus comprises a double catheter having an outer catheter and an inner catheter, the former having a pair of inflatable and deflatable cuffs spaced apart at a predetermined distance and having an ingress port located intermediate and between the inflatable cuffs and an outlet port located at about the proximal end of the outer catheter. The outer catheter, of course, has a smaller outer diameter than the inner diameter of the speculum so that the outer catheter can be introduced through and past the internal os of the sow's cervix, where the distal portion of the speculum is positioned, by inserting the outer catheter through the main passageway in the speculum. The inner catheter is, in turn, passed through the internal passageway of the outer catheter and the inner catheter has an egress port at the distal end thereof. Seals are provided at the distal and proximal ends of the outer catheter that seal against the outer perimeter of the inner catheter so as to allow the inner catheter to be slidingly received within the outer catheter while fonning a closed annular chamber between the inner surface of the outer catheter and the outer surface of the inner catheter.

Thus, in carrying out the process of removing the embryos from a sow, the double catheter apparatus is introduced into the uterus of the sow through the speculum and proceeds along into either the base of the left or right uterine horn as the case may be and both cuffs are inflated to seal off the entrance to that uterine horn. Once the outer catheter is in place the inner catheter is advanced by sliding it within the outer catheter and is progressed distally into the uterine horn of the sow slowly, while at the same time, a standard flushing liquid at a controlled temperature of 37 degrees C. is discharged from the distal egress port formed in the inner catheter. The flushing solution that is continuously discharged from the distal egress port of the inner catheter both flushes and also slightly dilates the uterine walls as the inner catheter is slowly advanced further into the uterine horn since the uterine passageway is sealed by the double cuffs of the outer catheter that are inflated. Hence, the distal end of the inner catheter can easily and without damage to the sow, be moved within the walls of the uterine hom to allow the inner catheter to be progressed along that horn until it is positioned with its distal end at the very tip of the uterine hom. This is also the area where the fallopian tube joins into the uterine horn, also called the utero-tubal junction and where the embryos are resting between days four to six post ovulation.

When the extreme end of the uterine hom is reached by the distal end of the inner catheter, the distal cuff on the outer catheter is deflated such that the continued introduction of the flushing solution, now at the utero-tubal junction of the uterine ho , is flushed so that the embryos contained with the entire uterine hom are forced caudadlly along the uterine hom, past the now deflated distal cuff of the outer catheter and into the egress port or ports that are formed in the outer catheter distal of the still inflated proximal cuff so that the embryos are flushed into the annular space between the external surface of the inner catheter and the inner surface of the outer catheter and the embryos and are continued to be flushed out of the outlet port located at or near the proximal end of the outer catheter to be progressed into a collection container where the embryos are isolated and recovered.

In the collection chamber, there is a sieve material having 75 micron openings that allow the embryos to be effectively and easily separated from the flushing solution and the solution can pass through and be drained off. During this period of time that the embryos are being separated in the collection chamber, that chamber is, of course, maintained at a temperature of 37 degrees C in order to maintain the viability of the embryos that are collected.

At this point, the embryos are separated and screened and treated in accordance with the aforementioned protocol. The embryos are continued to be maintained at the 37 degree C temperature and can remain viable at that temperature for a period of up to 80 hours so that the embryos can be shipped to any location in the world and pennit their placement into a synchronized surrogate mothering sow. The placement of the recovered embryo from the donor sow into the recipient sow can be accomplished through the use of a similar designed, albeit smaller, introducer and speculum that is placed through the cervix and at the desired location slightly distal to the base of either uterine horn of the surrogate mother sow.

The novelty and object of the present apparatus allows for the massive collection and transfer of embryos with the minimally invasive non surgical technique to be repeated hundreds of times during the life span of a donor. The entire ethos and business methods of the swine industry can be changed forever as a direct result of the present invention. Therefore inextricably linked to the apparatus is the specialized units or business methods for improved swine. The units are economical business units based on well defined swine operational units. The present apparatus combined with any of the aforementioned businesses separates the genetics of the progeny from that of the birth mother while concomitantly eliminating any transfer of disease from the boar.

Accordingly, with the present method of non-surgically removing, maintaining and transferring the swine embryos, a multitude of commercial businesses are made possible. Some of the identified methods of carrying out such business are listed herein:

1. Licensing of stand alone SUIS™ systems units by independent farm operators, small companies or veterinarians established to provide an embryo recovery and transfer business in a defined geographical area.

2. Create and supply high health surrogate multiplier and recipient herds. Create commercial donor feeder embryo herds of high health which can only be delivered and supported by embryo pregnancies in the surrogate herds.

3. Establish an Export Marketing business in each of the patent issued countries to select, collect and transfer preferred genetic lines to all recipient countries through certified disease free embryos. 4. Establish highest health herds with zero known pathogens as Nucleus herds which are replicated in conjunction with an approved Government contract for each country in order to develop disease free surrogate seed herds in the interested country. 5. Supply, from a zero known pathogen nucleus herd, disease free test pigs for University and Pharmaceutical research programs. 6. Provide a source of transgenic and immunologically designed disease free pigs for organ donor and xenographic projects which would eliminate the threat of human recipients contracting any known swine disease serotypes and reduce rejection of the donated tissue. Specifically, the present apparatus for the non-surgical removal of embryo from sows provides the basis for various new methods of doing business that heretofore were not possible with the present surgical of other methods of embryo removal and transfer previously described. The technology is licensable to independent farm owners that, to now, would be unable to remove the embryo on site, non-surgically and with lay persons.

The apparatus can also be used to create and supply high health multiplier and recipient herds of swine by initially non-surgically removing the embryo, using the known protocol to remove the pathogens from the embryo and placing the embryo into a disease-free sow. At the present, there is one known solitary isolated herd of disease-free swine in Canada comprising about 50 animals that have been maintained in a Level IV containment facility for over 50 years and that herd is housed within the Animal Disease Research Institute or A.D.R.I. at Napean, Ontario, Canada. The herd is maintained by the government of Canada and is available to others with the limitation that no surgical procedure can be performed on the animals. Hence, the value of the present non-surgical method and apparatus to remove embryos and to transfer those embryos non surgically to disease free animals is even more critical. The herd, however, is a source, available to all, non-exclusively, of disease free sows that can be used as a means in carrying out the various methods of doing business described herein. Thus, to date, while the disease free herd is available, there has been no use of that herd to transfer embryos into that high health herd and the recovery of embryo therefrom due to the prohibition against anesthetic and surgical procedures that heretofore have been required.

Accordingly, with the present method of non-surgical recovery and transfer of embryos, an entire new method of doing business has been made possible. The basis is to obtain from preselected herds with superior genetics 120 to 150 embryos and put those embryos through the ITES protocol cleansing process to remove all of the disease from the outer shell of each embryo. Then 10-12 embryos are transferred into each of 10 sows which have been correctly synchronized with the cycle of the donor. The pregnancies are allowed to reach full term and the piglets delivered naturally. Those piglets are left with the disease free surrogate sows until weaned and the females grown out until near puberty.

At this point, approximately one year in time, the group of about 50 zero known pathogen sows would be moved to an outside facility specially constructed to the same level of isolation for disease prevention, typically a Level III and using protocol Level IN for management of the site. Thus, the method has produced 50 nucleus sows that are uniquely disease free for later use in a commercial business. For example, of the 50 nucleus sows, the sows are split into two groups initially. One half is transferred with and become recipients of a specialized line of good mothering, easy delivering future surrogate line of sows. The other group becomes recipients of the highest quality meat production embryos. Once the two primary groups of zero pathogen seed herds are established, they would provide about 300 female pigs in total or 150 sows for each group so that the next generation of embryos would be ready to continue the process and expand and create the multiplier herds geometrically. At that point or any time later, new purpose specific embryos can be created or selected and placed in the zero known pathogen surrogates to establish a new line of business commercially.

Thus, the beginning of the new method of doing business is in the starting with a disease - free sows in a seed nucleus herd and maintaining that herd and some of the original genetics as a subgroup of the overall process.

With that basis, there is a further method of continuing a business, that of establishing and replicating the zero known pathogen surrogate herds in every country or location as required. This phase requires the proper level III buildings to be constructed and prepared to receive live surrogate gilts weighing about 30-40 pounds in order to provide the means to receive donor embryos, gestate and deliver offspring with the same zero known pathogen status as the original nucleus herd. Thus in the business, the operation includes the building, receiving of live surrogate weaned gilts and maintaining the proper Level III protocol IV status 24 hours a day, seven days a week and that process is replicated as often and to any specification for genetic traits that may be required or ordered. Thus, as a new business method, the present method and apparatus can be used to create, within a few generations, disease-free herds of swine throughout the world. Also, the use of the present non-surgical apparatus allows the commercial production of disease free embryos that can be distributed world- wide for both seed and multiplier herds around the world. The age and timing of the introduction of the disease free embryo is critical and would need to be synchronized to that of a recipient sow in any part of the world. Since the recipient in any given time zone must have her estrous cycle coordinated using hormones in accordance with the donor's time zone a universal standard of time must be used such as Zulu Time which is similar to Greenwich Mean Time and thereby eliminating any chance of miscalculating the post ovulatory age of either the donor's or recipient' s uterus.

Further the business of supplying disease free piglets is also enabled by use of the present inventive apparatus and such pigs are valuable for research facilities and large pharmaceutical testing companies that have a need for such pigs without any endemic diseases present. In addition, the producing of the disease-free swine makes possible the use of the swine for organ or tissue transplanting into humans since the availability of the disease-free swine raises the possibility of such transplanting of organs without the possibility of contracting swine disease serotypes.

The present invention and business methodology will obviously be a great economic advantage in countries where the supply of pork is wanting and the need for such meat is critical. Once the terminal boars and now for a first time terminal donor sows are developed, the best genetics in the world is available to any swine producer in just one generation. In addition, by making the transfer of embryos commercially viable, the embryos themselves can be the subject of a commercial commodity to be supplied throughout the world and used to repopulate the pig herds, disease free, that are thus unable to increase in size and efficiency or to produce the pigs that are best for the production of meat for consumption and thus, there can be a lucrative business in the harvesting and commercial supply of the embryos of pigs for introduction into surrogate mothers around the world. The entire business plan, which includes the aforementioned specific opportunities is impossible to undertake with the existing state of the art in surgical recovery and transfer of embryos.

These and other units of business units can be founded. If the methods which are currently available, such as conventional laparotomy and surgical embryo extraction, are used then it is simply not possible to conduct any meaningful business in this regard. However, the commercial transfer of swine embryos makes possible an entirely new array of business methodologies. Such business is a direct result of the present method and apparatus for the non-surgical removal of the swine embryos and through providing a means for those embryos to be introduced into swine herds throughout the world, also non surgically and free of any known disease.

These features and other advantages of the present invention will become more readily apparent during the following detailed description of the invention when taken in conjunction with the drawings herein.

Brief Description of the Drawings

FIG. 1 is a schematic view of the genital organs of a sow;

FIG. 2 is a longitudinal cross sectional view of the introducer and speculum used in connection with the present invention;

FIG. 3 is a schematic side view of an alternate embodiment of the introducer of Fig. 2;

FIG. 4 is a side schematic view of a dual catheter apparatus used in connection with the present invention; and FIGS. 5A-5F are a series of schematic views illustrating the method of removing embryos from a sow using the apparatus of Fig. 4.

Detailed Description of the Invention

Turning first to Fig. 1, there is shown a schematic view of the genital organs of a sow and, in particular, there can be seen, the ovarian bursa 10, the ovaries 12, the uterine hom 14, uterine body 16, cervix 18, vagina 20 vestibule 22 and the clitoris 24. With swine, as previously outlined, the embryos are developed in the uterine hom 14, of which there are two, and are distributed evenly across the uterine horn starting at about day seven post fertilization. Thus, in the harvesting or removal of those embryos, it is necessary to enter the uterine hom 14 and remove the embryos from the sow. While with other animals it is relatively easy to enter the uterine horn by passing a collection tube through the cervix; with swine, the cervix itself has a plurality of folds 26 and the physical makeup of the organ is extremely rigid and tight so as to make it difficult, if not impossible, to negotiate through the cervix with conventional medical instruments.

If a major force is used to carry out the introduction of an instrument, there is a strong likelihood of damage to the folds to the cervix and the ensuing blood is toxic to the embryos. Also the recovery of viable embryos is prohibitive by use of present instruments due to the long and tortuous path that can not be negotiated by any current collection catheter. Since, therefore, the use of current instruments via the cervix is not a solution to the removal of embryos due to the extreme difficulty of normal penetration of the cervix and only being able to flush the proximal portion of the uterine body, the only recourse for the removal of such embryos is by means of a surgical procedure where the sow is placed under general anesthesia and the delicate, invasive surgery is performed. Due to the need for such surgery, a skilled veterinarian is required in order to carry out the procedure in a very clean environment preferably that of a surgical suite, generally at the facilities of the veterinary clinic.

Turning now to Fig 2, there is shown a cross sectional view of an introducer 28 that can be used to relax, dilate and penetrate the cervix of a sow and to thus enable the possibility of the removal of embryos from the uterine hom of a sow without the need for a surgical procedure. As can be seen, the introducer 28 is specially designed to overcome the aforedescribed difficulties and can be used to pass through the folds of the otherwise impassible cervix of the swine and the introducer 28 comprises a speculum 30 that is comprised of a material such as stainless steel or a plastic like polyetherimide and has a hollow interior. Within the interior of the speculum 30 there is located a tube 32 that is affixed to a protruding tip 34 which is called the horn and extends through the distal open end 36 of the speculum 30. The protruding horn or tip 34 has a specially configured and shaped profile that is based upon an exponential curve, the purpose of which will be later explained.

The most advantageous materials for the protruding tip 34 are aluminum or titanium since both materials have strong crystalline bonding and efficiently transfer the oscillations from their proximal end to the distal end of the protruding tip 34 quite effectively. Certainly, from the standpoint of cost as well as the ability to form the material into the desired profile, aluminum is the preferred material to be used in formation of the protruding tip 34.

Affixed to the proximal end of the protruding tip 34 is an ultrasonic transducer 38, and which can be commercially procured as a piezoelectric crystal that vibrates at ultrasonic frequencies upon the application of a high voltage electric field. The ultrasonic transducer 38 is solidly affixed to the protmding tip 34, prefer by means epoxy and a threaded engagement between the distal end of the tube 32 that is screwed into the similarly shaped threads formed in the proximal end of the protruding tip 34 at 40.

The distal surface of the ultrasonic transducer 38 is also aided in its affixation to the protruding tip 34 by means of a layer of an adhesive 42, such as an epoxy, so that there is a very good mechanical bond between the ultrasonic transducer 38 and the protmding tip 34 and the axial vibrations of the ultrasonic transducer 38 are effective transmitted to the protruding tip 34. By means of the particular profile of the protruding tip 34, that ultrasonic axial vibrational movement is thus transmitted efficiently and effectively through the protruding tip 34 and are amplified at the distal end 44 of the protruding tip 34 to give the maximum axial displacement. The profile of the protruding tip 34 to the distal end 44 of the protruding tip is created by a exponential equation, and the preferred equation is Y = X ^"°²⁸ , or Y = X raised to the -0.28 power.

A spring means, such as a Bellevue washer which acts as a spring 46 can be sandwiched between the proximal end of the ultrasonic transducer 38 and a plain washer 48 solidly affixed to the tube 32 to apply a constant spring pressure ti at forces the ultrasonic transducer 38 against the proximal end of the protruding tip 34 to aid in the efficient fransfer of the vibrational energy and to allow for the expansion of the piezoelectric transducer 38. Suitable wiring can also be used to connect the ultrasonic transducer 38 to a source of electric power and, as shown, that electrical wiring can be contained within the tube 32 from the source of the electrical energy (not shown) and wires 50 connect that external source of energy to opposite ends of the ultrasonic transducer 38 so that the ultrasonic transducer 38 can be activated by the pulsing electrical field to generate the vibrational energy along the axial direction to eventually be transmitted to the distal end 44 of the protruding tip 34. The vibrations or oscillations relax and dilate the cervix to enable the introducer 28 along with the speculum 30 to penetrate through the entire length of the cervix.

Therefore, as explained, the aforedescribed introducer 28 can be used with the present invention to enable a lay person to gain access to the uterine horns of the sow through the cervix, a feat that has heretofore been beyond the reach of the owner of a herd of swine including nearly everyone else and, in connection with the other apparatus herein described, enables a lay person or non- veterinarian to be able to harvest the embryos of the sow for transfer to a surrogate mother.

Turning now to Figure 3, there is shown, a schematic view of an alternate embodiment of an introducer 28 that can be use in connection with the present invention, hi Figure 3, the protruding tip 34 is axially vibrated by means of a rod 50 located within the speculum 30 and a mechanical vibration is provided to the protruding tip 34 by a mechanical vibrating means located at the proximal end of rod 52 and one typical means of producing the mechanical vibrations is by the use of a cam or crankshaft 54 that rotates to cause the rod 50 to vibrate or oscillate in an axial direction - powered by a high speed motor 56 operating at a speed of about 2000 rpm or more. Thus, by a mechanical vibrator, the similar axial vϊbrative motion can be produced and transmitted to the distal end 44 of the protruding tip 34 to achieve the same results as the prior embodiment of Figure 2.

As will become clear with respect to the later description of the method of carrying out the present invention, the concentration of the vibrations or oscillations in an axial direction at the distal end 44 of the protruding tip 34 and the particular profile of the protmding tip 34 itself allow the introducer 28 to enter the cervix of the sow and the vibration causes a relaxation and dilation of the cervix so that the introducer 28 can be manually pushed through the cervix without damaging the cervix so as to carry along and locate the open end 36 of the speculum 30 at the entrance to the uterine body of the sow. At that point, the tube 32 and the protmding tip 34 can be withdrawn from the speculum 30 and the speculum 30 left in position to provide access to the uterine horns of the sow for harvesting of the embryos.

Turning now to Fig 4, there is shown a schematic view of a catheter apparatus 58 constructed in accordance with the present invention. As shown, there is an outer catheter 60 and an inner catheter 62 that is generally coaxially aligned with the outer catheter 60 and is dimensioned so as to be slidably movable within the outer catheter 60 and provide for the annular spacing of about 0.125 to about 0.150 of an inch therebetween. The outer catheter 60 may be of the same material as the inner catheter 62, however, the outer catheter 30 may be of a heavier gauge material or a material having a higher durometer than that of the inner catheter 62.

The outer catheter 60 has a distal end 64 that is formed with a slight curve 65 at 1 cm. proximal to its most distal end 64 so as to be able to be directed into the entrance of either uterine horn of the sow and has a proximal end 66. Apair of inflatable cuffs are also provided on the outer catheter 60 and, as shown, there is a distal cuff 68 and a proximal cuff 70. Both the distal cuff 68 and the proximal cuff 70 can be separately inflated and deflated by means of individual lumens *(not shown) formed in the wall of the outer catheter 60 in conventional manner as desired by the user. Coextruded in the wall of the outer catheter 60 are two independent groups of optical fibers 67 which allow for the visualization of the endometrium and to aid in the correct placement of the outer catheter in the uterine horn of choice. The ingress light fibers are connected to a powerful light source while the reflected light is projected through a camera system and onto a color monitor preferably with split screen capabilities.

An egress port or ports 72 are formed in the outer catheter 60 intermediate between the distal and proximal cuffs 68, 70. An outlet 74 is also formed in the outer catheter 60 adjacent to or near the proximal end 66 of the outer catheter 60 and that outlet 74 is adapted to be connected to a tubing or conduit 75 to so that fluid within the internal channel 76 of the outer catheter 60 can be released through the outlet 74 as will be later explained. Thus, the outlet 74 may include Luer lock fitting or other connector that can be easily facilitate the connecting and disconnecting of the internal channel 76 of the outer catheter 60.

. The internal channel 76 of the outer catheter 60 is otherwise a sealed area except for the egress ports 72 and the outlet 74 since that internal channel 76 is sealed at its ends by a fluid seal 78 formed at the proximal end between the outer catheter 60 and the inner catheter 62 and a similar fluid seal 80 is formed at the distal end 66 of the outer catheter to seal that distal end 66 against the inner catheter 62. Both of the seals 78 and 80 provide a seal between the outer catheter 60 and the inner catheter 62 while allowing the inner catheter 62 to freely move axially along the outer catheter 62 so that the inner catheter 62 can be extended from the outer catheter 60 by the user as will become clear.

As to the inner catheter 62, there is a distal end 82 and a proximal end 84 with an egress port 86 formed in the distal end 84 of the inner catheter 62. An inlet 88 is provided in the proximal end 84 of the inner catheter 62 that is adapted to be connected to a source, under pressure, of a flushing fluid at a temperature of 37 degrees C. The flushing fluid is a standard fluid used in the flushing and handling of embryos and is readily available commercially. A pumping and heating system (not shown) can be used to provide the flow of the flushing fluid into the inner catheter 62 at that prescribed temperature and one such heating and pumping system is shown and described in U.S. Patent application entitled " Heater With Removable Cartridge" and filed on the same day as the present application.

In addition, the inner catheter 62 is preferably constmcted having a fiber optic viewing system coextmded in its wall and connected to a camera and viewed on the color monitor with a split screen and shared with the view from the distal end of the outer catheter 60. This enables the user to look into an external viewing monitor to view the progress of the distal end 82 of the inner catheter 62 to guide its movement within the uterus of the sow in a manner to carry out the method of the present invention. The use of a fiber optic viewing system is also a conventional system that is commonly used on a wide variety of medical devices such as endoscopes, endotracheal tubes and the like to guide their introduction into the desired location within the animal or human patient.

As another component of the overall embryo removal system, there is provided a system to facilitate the separation and isolation of embryos received from the outer catheter 60 and that system includes a collection container 90 that is also connected to the conduit 75 to receive fluid from the outer catheter 60 and the container 90 includes a fine mesh screen 92, having a mesh of about 75 microns. An overflow drain 94 is formed in the container 90 for the removal of the flushing fluid therefrom. A sump 96 is provided at the bottom of the container 90 that receives the embryos that are removed from the sow in carrying out the method of die present invention and a passageway 98 to enable the user to recover those embryos. To maintain the collection container 90 at the proper temperature of 37 degrees C, there also can be present a heater 100 of a conventional wrap around design that surrounds the external peripheral surface of the collection container 90 as well as all connecting tubing.

Thus, with the foregoing description of the apparatus used with the present invention, the method of the non-surgical removal of the embryo from a sow can be described.

Accordingly, turning now to Figures 5A -5F, there are shown, schematic views that illustrate the method of the present invention using the previously described apparatus to remove embryos from a sow and where Fig 5A shows the introducer 28 with the speculum 30 in position to be inserted through the cervix 18; Figure 5B is a schematic view showing the introducer 28 and speculum 30 having passed through the cervix; Figure 5C shows the introducer 28 removed, leaving the speculum 30 in position with the distal end located at the entrance to the body of the utems 14; Figure 5D shows the catheter apparatus having been inserted through the speculum 30 and in position at the entrance to the uterine horn 14 with both the distal and proximal cuffs 68, 70 inflated and sealing off one of the uterine horns, Figure 5E shows the inner catheter being advanced through the uterine horn and Figure 5F shows the inner catheter advanced to the extreme location of the uterine horn and with the distal balloon of the outer catheter deflated so that the embryo can be flushed from the tip of the uterine hom. The description of the method illustrated by Figure 5 A- 5F will be taken along with the more detailed description of the catheter apparatus 58 of Figure 4.

Thus, in Figure 5 A there can be seen that the introducer 28 is located within the speculum

30 in position just external of the cervix 18 and therefore is located so as to be introduced into and through the cervix 18 of the sow. At this point, the vibrational energy is applied to the protruding tip 34 so that the vibrations allow the user to easily pass the introducer 28 through the cervix 18 without causing damage to the folds of the internal surfaces of the cervix 18.

In Figure 5B, therefore, the introducer 28 and the speculum 30 have been advanced through the cervix 18 and the distal end 44 of the protruding tip 34 is at the entrance to the uterine body 14a and, accordingly, the vibrational energy to the protruding tip 34 can be terminated. As shown in

Figure 4C, the introducer 28 has been fully removed from the sow and only the hollow speculum

30 is left in position for the further steps in the removal of embryo from the sow.

Accordingly, in Figure 5D, the speculum 30 is the position of Figure 5C, however, the catheter apparatus 58 has been inserted through the speculum 30 such that the outer catheter 60 extends from the open distal end of the speculum 30 and by orienting the curved tip either to the right or left the outer catheter 60 can be introduced and placed a short distance up into the uterine hom of choice. At that point in time in die present method, both the distal cuff 68 and the proximal cuff 70 are inflated to effectively seal off the entrance to the uterine hom 18. Turning now to Figure 5E, there can be seen that the inner catheter 62 has now been extended distally and outwardly from the outer catheter 60 while that outer catheter 60 remains in position sealing off the entrance to the uterine horn 14.

As previously explained, as the inner catheter 62 is advanced manually by the user, the flushing fluid is continually being discharged from the distal end 82 of the inner catheter 62 and that flow of fluid serves to slightly blow up or expand the area of the uterine hom 14 such that the advancement of the distal end 82 of the inner catheter 62 is relatively easily. As also indicated, at this point, the user is employing the fiber optic viewing system to manipulate and carefully control the advancement of that distal end 82 of the inner catheter 62 into the uterine horn 14. The diameter and durometer is such that the inner catheter 62 stays rigid enough to advance and not coil up or fold back on itself.

Thus the distal 82 end of the inner catheter 62 can continue to be advanced within the uterine horn 14 by the user and manipulated manually to control and direct the movement in the desired direction, it being noted that the distal and proximal cuffs 68 and 70 are still inflated to seal the entrance to the uterine hom 14 and maintain the uterine hom 14 as a sealed chamber.

Finally, in Figure 5F, the distal end 82 of the inner catheter 62 has reached the remote area of the uterine hom 14 so that the embryos located in this area can be carried back to the proximal portion of the uterine hom and egress with the flushing solution from the uterine horn 14. As such, the distal cuff 68 is deflated and the flow of flushing fluid continued. By deflating the distal cuff 68 of the outer catiieter 60, there is a pathway for the fluid to travel such that the embryos are flushed toward the entrance to the uterine hom 14 and the flushing fluid and the embryos contained therein can continue past the now deflated distal cuff 68 to enter the egress port 72 of the outer catheter 60, continuing through the internal chamber 77 of the outer catheter 60 to the outlet 74 of the outer catheter where the fluid containing the embryo are caused to enter the conduit 76 to be transferred to the collection container 90 where the embryo are, as explained, isolated from the flushing fluid and removed for further processing.

The recovered embryos have thus been removed from the utems of the sow without the need for any surgical procedures and the embryos can be processed and isolated for commercial distribution or use in a herd of swine that has ready and synchronized sows available. To that end, die embryos are further processed by the cleaning, selecting and washing with enzymes all established in accordance with the published protocol of the International Embryo Transfer Society to produce pathogen free embryos that can be used for placement in local recipient herds of swine or shipped to remote herds throughout the world.

The placement of the embryos can also be accomplished by the use of the present introducer and speculum system by carrying out the first steps of the present procedure, that is, up to the placement of the speculum with its distal, open end positioned at the entrance to the uterine horn.

With the insertion of the embryos, however, a smaller introducer and speculum is utilized since the use of the dual catheter system is not needed to place the embryos at the desired location within a uterine hom. Once so located, a straw containing the embryos can readily and manually be inserted into the speculum and the embryos deposited into one of the uterine horns. The natural process is, once the embryos have been introduced into the entrance of the uterine horn, to spread out and become evenly spaced along the walls of both uterine horns so that the remaing natural process of gestation and birth of the piglets can proceed in the normal course.

Claims

CLAIMS We claim:

1. The method of doing business by creating and supplying high health surrogate multiplier and recipient swine herds said method comprising a) non-surgically removing embryos from a sow, b) placing those embryos into a disease free surrogate sow, c) recovering the resulting piglet that is a disease free piglet, repeating steps a) through c) to produce a plurality of disease-free swine.

2. The method of doing business by the distribution of swine embryos, said method comprising non-surgically removing embryos from a sow, processing the embryos to remove pathogens from the embryos, distributing the pathogen-free embryos to be used in surrogate mother sows to establish a disease free seed herd.

3. The method of doing business by the distribution of living piglets, said method comprising non-surgically removing embryos from a sow, processing the embryos to remove pathogens from the embryos, distributing the pathogen-free embryos to be used in surrogate mother sows having no known pathogens, allowing the surrogate mothers to bear piglets, and commercially distributing the piglets.

4. The method of doing business by the harvesting organs from a swine, said method comprising non-surgically removing embryos from a sow, processing the embryos to remove pathogens from the embryos, distributing the pathogen-free embryos to be used in surrogate mother sows having no known pathogens, allowing the surrogate mothers to bear piglets, and harvesting organs from the piglets for organ transplant operations or zeno graphic projects.

5. The method of doing business by the commercial distribution of swine embryos, said method comprising passing a catheter apparatus through the cervix of a sow, flushing the embryos from the uterine hom of the sow to recover the embryos, isolating the desirable embryos and providing the removed embryos to recipient users throughout the world for placement in surrogate mother sows.

6. A method of doing business as defined in claim 5 wherein said step of passing a catheter apparatus through the cervix of a sow comprises using a vibrating introducer to provide a pathway through the cervix.

7. A method of doing business as defined in claim 6 wherein the step of using a vibrating introducer comprises using a vibrating introducer having an ultrasonic oscillating frequency.

8. A method of doing business as defined in claim 5 wherein said step of providing the removed embryos comprises providing embryos throughout the world free from all pathogens known to cause disease in swine.

9. A catheter apparatus for non-surgically removing embryo from the uterine hom of a sow, said catheter apparatus comprising an outer catheter having a distal end and a proximal end and an inner catheter having a distal end and a proximal end, said inner catheter dimensioned to be slidably received within said outer catheter, a sealing means located at the distal and proximal ends of said outer catheter to seal against said inner catheter when said inner catheter is slid within said outer catheter, said outer catheter having at least two inflatable and deflatable cuffs spaced apart and having an ingress port formed therebetween, said outer catheter further having an outlet for withdrawing fluid from said outer catheter, said inner catheter having an egress port at said distal end and an inlet formed at said proximal end, said outer catheter adapted to be positioned having said distal end at the entrance to the uterine hom of a sow and said inner catheter adapted to be slidably advanced into the uterine ho of a sow to remove the embryo therefrom.

10. A catheter apparatus for non-surgically removing embryo from the uterine horn of a sow as defined in claim 9 wherein each of said at least two cuffs are separately and independently inflatable and deflatable.

11. A catheter apparatus for non-surgically removing embryo from the uterine horn of a sow as defined in claim 9 wherem said inner catheter is manually mampulatable to progress said distal end of said inner catheter to a remote distal area of the uterine hom of a sow.

12. A catheter apparatus for non-surgically removing embryos from the uterine homs of a sow as defined in claim 9 wherein said inner catheter his comprised of a material of a lower durometer than the material of said outer catheter.

13. A system for non-surgically removing embryos from the uterine horn of a sow, said system comprising a catheter apparatus comprising an outer catheter having a distal end and a proximal end and a inner catheter having a distal end and a proximal end, said inner catheter dimensioned to be slidably received within said outer catheter, a sealing means located at the distal and proximal ends of said outer catheter to seal against said inner catheter when said inner catheter is slid within said outer catheter, said outer catheter having at least two inflatable and deflatable cuffs spaced apart and having an ingress port formed therebetween, said outer catheter further having an outlet for withdrawing fluid from said outer catheter, a collection container for receiving the fluid containing embryo from said outlet of said outer catheter and for separating the embryo from the fluid, said inner catheter having an egress port at said distal end and an inlet fonned at said proximal end, a heating and pumping system for providing fluid at a predetermined constant temperature to said inlet of said inner catheter to discharge the fluid from said egress port of said inner catheter, said outer catheter adapted to be positioned having said distal end at the entrance to the uterine hom of a sow and said inner catheter adapted to be slidably advanced into the uterine horn of a sow to remove the embryos therefrom.

14. A system for non-surgically removing embryos from the uterine horn of a sow as defined in claim 13 wherein said heating and pumping system causes fluid to be discharged from said distal end of said inner catheter throughout the time said inner catheter is advanced into the uterine horn of a sow.

15. A system for non-surgically removing embryo from the uterine hom of a sow as defined in claim 13wherein said heating and pumping system provides the fluid at a temperature of about 37 degrees C.

16. A system for non-surgically removing embryos from the uterine ho of a sow as defined in claim 13 wherein each of said at least two cuffs are separately and independently inflatable and deflatable.

17. A method of non-surgically positioning a speculum within the cervix of a sow, said method comprising the steps of: providing an introducer having a tip that is profiled in the configuration of an exponential curve, providing a speculum having a distal end to be introduced through the cervix of a sow, locating the tip of the introducer at the distal end of the speculum, positioning the tip of the introducer at the external area of the cervix of a sow, manually inserting the introducer into and through the cervix of a sow while simultaneously causing the tip to vibrate axially to position the end of the speculum at the entrance to the uterine body of a sow.

18. A meftiod of non-surgically positioning a speculum within the cervix of a sow as defined in claim 17 wherein said step of causing the tip to vibrate axially comprises vibrating the tip at an ultrasonic frequency.

19. A method of non-surgically positioning a speculum within the cervix of a sow as defined in claim 17 further includmg the step of removing the introducer from the speculum to leave die speculum in position with the distal end of the speculum at the entrance to the uterine body of a sow.

20. A method of removing the embryo from the uterine hom of a sow, said method comprising the steps of: providing a catheter apparatus comprising an outer catheter having distal and proximal ends and an inner catheter having distal and proximal ends and being sliding received in the outer catheter and sealed within the outer catheter at the distal and proximal ends of the outer catheter, positioning the distal end of the outer catheter at the entrance to the uterine hom of a sow, sliding the inner catheter through the outer catheter such that the distal end of the inner catheter is positioned at the tip area of the uterine hom of the sow remote from the entrance, discharging a flushing liquid from the distal end of the inner catheter to force the embryos backwardly toward the entrance to the uterine hom; and withdrawing the flushing liquid containing the embryos from the sow at the entrance to the uterine horn of a sow.

21. A method of removing the embryo from the uterine hom of a sow as defined in claim 20 wherein said step of sliding the inner catheter through the outer catheter includes the step of discharging a flushing fluid from the distal end of the inner catheter while progressing the inner catheter through the uterine hom of the sow.

21. A method of removing the embryo from die uterine hom of a sow as defined in claim 20 wherein said step of sliding the inner catheter through the outer catheter includes the step of sealing the entrance to the uterine hom of a sow.

22. An introducer for relaxing, dilating and penetrating the cervix of a sow, said introducer comprising a protruding tip having a proximal end and a distal end, said protruding tip having an arcuate profile formed based upon an exponential curve, said introducer having a means to create axial vibrations in said distal end of said protruding tip to enable the introducer to relax the cervix to allow said protmding tip to readily pass therethrough.

23. An introducer as defined in claim 22 wherein said means to create axial vibration comprises an ultrasonic transducer affixed to said proximal end of a said protmding tip.

24. An introducer as defined in claim 23 wherein said ultrasonic transducer is affixed to said proximal end of said protmding tip by means of an epoxy adhesive.

25. An introducer as defined in claim 23 wherein said ultrasonic transducer is affixed to said protruding tip by means of a threaded engagement.

26. An infroducer as defined in claim 22 wherein said ultrasonic transducer is affixed to said proximal end of said protmding tip by means a spring biasing.

27. An introducer as defined in claim 26 wherein said spring bias comprises a Bellevue washer.

28. An introducer as defined in claim 22 wherein said vibrating means comprises a mechanical vibrator coupled to said protmding tip.

29. An introducer as defined in claim 28 wherein said mechanical vibrato comprises a cam means adapted to rotate to cause axial movement of said protruding tip and a high speed motor to rotate said cam or crankshaft.

30. An introducer as defined in claim 22 wherein said profile of said protmding tip is created by the exponential equation Y = X raised to the -0.28 power.

31. An introducer as defined in claim 22 wherein said protmding tip consists of a material selected from the group of aluminum and titanium.

32. An introducer as defined in claim 31 wherein said protruding tip is comprised of aluminum.