CA1299942C - Two part mastitis cannula cap - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
A system having a microprocessor to provide an adjustable control of the temperature and pressure of water at the outlet of a single adjustable valve. The water temperature at the valve outlet is constantly monitored. A
processor compares the actual water temperature with a specif-ically requested temperature for the water at the valve outlet, and provides signals to relays and a control circuit for a motor which adjusts the temperature of water by the relative proportions of hot and cold water discharged through the valving to the outlet. The system with the microprocessor provides a multi-speed control of the motor having variations in the speed of adjustment of the valve so as to effect a quick valve movement to a temperature in the vicinity of the desired temperature after which fine tuning provides the exactly requested temperature. The calculations of the microprocessor by including continuous monitoring of the valve positions and the water temperature coordinates the relative positioning of the valve in the mixing of the hot and cold water with the regulations of the water temperature by mixture in the valve so that the instructions from the microprocessor in response to the water temperature are accommodated to fully open and fully closed positions of the valve.

Description

~ lZ99942 . .

TW0 PART MAS,~TIS CANNU~A CAP

r ieid of the ;nvention The present invention is dlrected generally to a two part cap for a cannula. More particularly, the present invention ,s directed to a two part cap for the cannula of a mastitis infusion syringe. Most specifically, the present invention is directed to a two part, separable mastitis infus on cannula cap which is useable to limit the cannula's insertion aepth into the teat canal of a dairy cow. The two part mastitis~cannula ca?
includes an outer or overcap which is positionable at a free or distal end of an elongated inne~ cap. The outer cap is dimensioned to expose only a portion of the mastitis syringe cannula when this outer cap is removed .rom the inner ca?. This insureC that the cannula's insertion depth can be ef'ectively l mi'ed to less than the length of the .eat canal when only 'he outer czo is removed. 3acteria thus cannot be carried into the teat cistern by ~he mast'tis .reatment cannula eau-?ped with the two part cap when only the outer cap is removed.
~esc,i~tion o' ~he Prior Art 30vine mastit~s is a serious problem which af'licts large number~of dairy cows. This mast~tis, or inflammat.ion of ~q~1 the cow's mammary sland, strikes substantial percentages of cows in dairy herds and has a detrimental effect on milk production and herd pro'itabllity. The generally followed method of ~; treatment for bovine mastitis has been the administration of ::

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12999~2 various antibiotic preparation into the cow's udder through the teat canal. A mastitis infusion syringe, which carries the antibiotic preparation, typically is equipped with an insertion cannula having a length of 20 to 25 mm. Thl~ cannula and syringe assembly is provided from the antibiotic supplier as a molded plastic, disposable unit which is prefilled with the treatment antibiotic. A single piece plastic cover, which typically snap fits onto the hub of the syringe at the base of the cannula, is used to cover the cannula prior to use. At the time o' treatment, the protective cap is removed from the mastitis treatment syringe cannula and the cannula end is inserted into the cow's teat end, passed through the teat canal, and positioned within the teat cistern. Once the cannula has been so pos~ioned, the syringe is utilized to deposit the treatment antibiotic directly into the cow's teat cistern.
~ ecent studies have sugoested tha~ the previously practiced 4ull cannula insertion techniaue may actuaily reduce rather than enhance the ef'ectiveness Oc the treatment. This research has indicated that in some instances infection in the teat canal are carried into the teat cistern by the mastitis cannula during full cannula insertion. Lhe cow`s teat canal is approximately 1 cm in length and has a very narrow lumen. This canal helps to prevent bacteria Crom entering the cow's udder.
Some bacteria may survive in secretions in the distal teat canal but are prevented from traveling the full length Oc the canal.
These bacte-ia may be aided in their travel up the teat canal by :: ~

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lZ99942 the cannula as it passes through the canal during full cannula insertion. It has also been found that the teat canal or duct kera~in layer, which helps control bacterial penetration lnto the udder, may be damaged by full cannula insertion. This full length cannula insertion may also cause the distal lumen to become larger than normal thus allowing increased bacterial travel and penetration. ~acteria which might otherwise exist for months in teat canal keratin without causing mastitis might enter the teat cistern area during .ull cannula insertion.
As a result of these above-discussed studies, there is now being utilized a partial insertion technique wherein the mastitis cannula is inserted into the teat end and up the teat canal only to a depth of generally about 3 mm. This technique appears to be beneficial in the treatment of mastitis but has made treatment procedures more time consuming for the dairyman.
It is necessary that the cannula insertion àepth be limited to generally about 3 mm to avoid the teat canal ~erat~n damage and transport of bacteria from the teat canal along into the teat cistern which was caused by the full insertion techniaue.
There presently exists no commercially prepared, readily useable yet disposable mastitis infusion syringe assembly which will allow the user to ~uickly and easily control the depth of cannula insertion thus rendering this partial insertion treatment effective; Individual measurements of each insertion depth are time consuming and are apt to be inaccurate. ~ere guessing is even less accurate and may make the treatment Oc little value. It will thus be seen that a need exists for a mastitis treatment cannula assembly whlch will accurately, positively, and reproducably limit the depth of cannula insertlon while not increasing treatment time, cost or the rlsk of contamination. The two part mastitis cannula cap assembly of the present invention provides a very satisfactory solution to the problem.
Sum~arv o' the Invention It is an object of the present invention to provide a mastitis treatment cannula and syringe assembly.
Another object of the present invention is to provide a mastitis cannula cover having a depth of insertion limiting capabili~y.
A further object of the present invention is to provide a two part mastitis cannula cap.
Yet another ob~ect o' the present invention is to provide a two part mastitis cannula cap having an insertion depth limi'ing outer cap.
Still a further object of the present invention is to provide a two part mastitis cannula cap which will allow full cannuia insertion.
Yet still another ob~ect of the present invention is to provide a two part mastitis cannula cap usable with existing treatment syringes.
Even yet a further object of the present invention is to ?rovide a two part mastitis cannula cap that is eas~ to ~299942 handie, does not leak, is sterile, and will not harm the teat end.
As will be discussed in greater detall ln the doscrip-tion of the preferred embodiment which is set forth subsequently, the two part mastitis cannula cap assembly in accordance with the present invention includes an inner cap which snaps onto the base of the cannula at a first end, and which has a relatively wide outer or distal end; and an outer cap which is removably carried on the distal end of the inner cap and which includes an outer rim or flange to facilitate removal. The outer cap covers generallv about the outer 3 mm of the mastitis cannula which ; extends through an aperture at the distal end of the inner cap I and, when removed, allows only partial depth insertion of the , cannula into the teat canal. This depth o' insertion is limited j by tbe relat'vely large diameter of the dlstal end of the ~nnor cap which also stabilizes the cannula against the teat end and prevents leakage during infusion of the treatment material during utilization of the partial insertion technique.
¦ The two part mastitis cannula cap in accordance with .
the present invention includes an outer circumCerential .im or ''ange which is formed as a part of the outer cap and which facilitates easy removal of this first cap The herdsman or the i li~e who ~s responsible for the treatment Oc the cattle can ; readily remove the outer cap, e~pose only that length of cannula required for part,al insertion, and effect ~n,usion o' ~he treatment ma~erial in an ef'icien~, predictable manner. Since ~;''' -.

~299942 the depth of cannula insertion is controlled by the abutment of the wide diameter distal end of the inner cap agalnst the teat end, there is no chance for insertion of the cannula to an improper depth. Thus the partial insertion process is done to the same depth every time.
Should a full insertion procedure be desired, the complete cap assembly can be removed from the cannula by separation of the first or proximal end of the inner cap from the base of the cannula generally as has been accomplished in the past. Once the inner cap has been removed to expose the full lens~h of the cannula, full insertion can be done in the conventional manner.
The two part mastitis cannula cap in accordance with the present invention provides the user with a choice. He can remove only the outer cap and utilize the cannula in a part inserSion treatment procedure, or he can remove both the inner and outer caps to expose the full length o. the mastitis control cannula for a full insertion procedure. The two par~ cap is usable with existing mastitis treatment cannula and syringe assemblies, is not expensive to manufacture and is thus disposable, and provides treatment flexibility not previously available. The two part mastitis cannula cap of the present nvention is a significant advance in the art and is an effective tool in the control of bovine mastitis.

~- -Brief Descr~tion of the Drawinas While the novel features of the two part mastitis cannula cap in accordance with the present invention are set forth with particularity in the appended claims, a ull and complete understanding of the invention may be had by referrlng to the detailed description of the preferred embodiment as is set forth hereinafter and as illustrated in the accompanying drawings in which:
Fig. 1 is a side elevation view, partly in section, of a mastitis treatment syringe and cannula utilizing the two part cap o' the present invention;
Fig. 2 is a cross sectional view oS the cannula and cap assembly taken along line II-II of Fig. ; and Fig. 3 is an enlarged cross sectional side view o. a portion of the outer and inner caps of the present invention.
Descri~t on o, the Preferred Embodiment Turning initially to Fis. 1 there may be seen a two part mastitis cannula cap, generally at 10, in accordance with the present invention. Two part cap assembly 10 includes an outer or overcap ;2 and an inner cap 14. .his two part mastitis cannula cap 10 is shown in Fig. l in conjunc~ion with a typical mastitis in'usion syringe 16 that conventionally is a lO ml disposable plastic syringe which is intended Cor a one time usage. A proximal or cirst end of an insertion cannula 18 is fused to a reduced diame~er end 20 of syringe 16. Insertion cannula 18 typically is 20 to 25 mm in length and has a generally ., ~ .

12999~2 cylindrical hollow body 22 with a through bore 24. A generally conical shaped hub 26 is formed at first or distal end 28 of cannula 18 and this hub 26 is 'used to the reduced diameter end 20 of syringe 16. An annular groove 30 ls formed ln the end 20 of syringe 16 adjacent cannula hub 26. This syringe 16 and cannula 18 assembly is a typlcal configurat~on in which a bovlne mastitis treatment material is supplied. While the two piece mastitis cannula cap 10 ln accordance with the present invention will be discussed for use with this syringe and cannula assembly, it will be understood that the size of the syringe, the overall length of the cannula and other similar structural characteristics of this syringe and cannula assembly, which form no part of the subject invention, could be changed.
Two part mastitis cannula cap 10 includes, as was ndicated above, an outer cap 12 and an inner cap 14. As may be seen in Fig. 1, outer cap or overcap 12 is somewhat cup-shaped and has a general y cylindrical siaewall 32. A somewhat planar end wall 34 of outer cap 12 is joined to a first end of cylindrical sidewall 32 and has a cent~al projection 36 which forms an ~nterior concavity 38 that receives a free end or distal tip 40 of the insertion cannula 18. Concavity 38 has a depth of generally about 3 mm, depending on the length of free end ~0 o' cannula 22 which extends beyond inner cap 14, in a manner to be discussed shortly. Concavity 38 and cannula tip 40 are cooperatively sized to ,orm a snug, leak resistant in~erfit. An enlarged annu'ar outer flznge ~2 is joined to outer cap i2 zt the . ~ , .,,: ' ' . . ` .

second end of sidewall 32 opposite planar endwall 34; This outer flange 42 should be sufficiently large to facilitate grasping of outer cap 12 when this outer cap 12 is to be removed from ~nner cap 14. In the preferred embodiment, this annular outer flange 42 may have a diameter of generally about 10 to 20 mm.
Inner cap 14, as may be seen most clearly in Fig. 1, is generally in the shape of an elongated cylindrical sleeve having a tubular sidewall 50. A snap end 52 of inner cap 14 has a radially inwardly extending lip 54 that is receivable in annular groove 30 formed at the ~unction of syringe end 20 and hub 26 of cannula 18. Detachment of the snap end 52 of inner cap 18 from syringe 16 is achieved by bending inner cap 14 to unseat lip 54 from groove 30.
Inner cap 14 terminates at its distal end 56 in an outer end face 58 that has a central aperture 60 through which the free end 40 of insertion cannula 18 passes. Lhe outer end face 58 of inner cap 14 has a relative;y wide diameter, generally in the range of about 5 to ~ mm and is smooth and somewhat rounded at its peripheral ed~es 62.
Outer cap 12 overlies the distal end 56 of inner cap 14, as mzy be seen in Figs. 1 and 3. An inner surface 70 of outer cap sidewall 32 slidingly cooperates with an outer surSace 72 of tubular sidewall 50 of inner cap 14 to effect retention of outer cap 12 on the distal end 56 of inner cap 14. Securement of inner cap 12 to outer cap 14 is enhanced by the cooperation of a ~ pa r of opposed protrusions 76, formed on the outer surface ~2 of ,, ~, lZ99942 tubular inner cap sidewall 50, with a circumferentlal recess 80 cooperatively located in the inner surface ~0 of outer cap sidewall 32. Alternatively, the number of protrusions ~6 could be increased or a continuous rim (not shown) could be substituted. These protrusions ~6, or rim, and circumferential recess 80 are sized so that a pulling or pushing force exerted on outer cap annular flange 42 will effect separation of outer cap 12 from inner cap 14 and not separation of inner cap 14 from syringe end 20. Separation of inner cap 14 from syringe end 20 is more easily accomplished by grasping the tubular sidewall 50 of inner cap 14 and by utilizing a bending force to unseat lip 54 from groove 30. Thus the two separating forces are of differing ~ypes so that separation will occur at the desired point.
In use, ~he two part mastitis cannula cap assembly in accordance with the present invention allows the dairy farmer, veterinarian, herdsman, or the like to practice whichever n'usion procedure he feels will be more effective. Should partial insertion be desired, the outer cap's outer flange 42 is srasped and the outer cap 12 is removed. This exposes the free or distal end of insertion cannula. In accordance with present procedures, generally about 3 mm of the cannula free end 40 projects beyond the relatively wide diameter smooth end face 58 of inner cap 14. Since the teat canal o' a cow is approximately 1 cm in length, the 3 mm projection o, cannula free end 40 limits cannula insertion depth to a point within the teat canal and not into the teat cistern. Thus partial cannula insertion, to the , .

correct depth can be quic~ly accomplished. The relatively large dia...eter outer end face 58 of the inner cap serves to stabilize the infusion cannula against the teat end while the free end 40 of the cannula is inserted partially lnto the teat canal. This wide end face also minimizes leakage of the material being infused. Since this end face 58 is smooth with gently rounded corners it will not harm the teat end. Additionally, since the teat canal is ~uite small in diameter, there is no possibility of the generally wide, large diameter end face 58 of the inner cap being inserted into the teat canal.
If full insertion of the mastitis treatment cannula is desired, this can readily be accomplished by removal of both the outer and inner caps as a single assembly. As discussed previously, this is accomplished by grasping the tubuiar sidewall 50 of the inner cap i4 and by exerting sufficient bending force to unseat the lip 54 on the snap end or proximal end 52 of the inner cap 14 'rom its cooperating groove 30 at the Juncture of the syringe body 16 with the attached cannula 18. This exposes .he entire length o' cannula 18 so that full insertion of ~he cannula into 'he teat cistern through the teat canal can be accomplished.
T~e overall length of the two part mastitis cannula cap of the present invention will be generally in the ~ of 35 to 7~
87 40 mm. This dimension is determined by the length o- the cannula and is not particularly critical in itself. The length of the ' inner cap 14 wi~h .espect ~o the length Oc the cannula 18 is important because the difference in lengths between the shorter inner cap 14 and the longer cannula 18 determines the length of cannula free end tip 40 protrusion beyond the end face 53 of inner cap 14. As discussed above, a pro~ection of generally about 3 mm is believed to be proper for optimal infusion of the mastitis treatment antibiotic preparatlon into the teat canal.
The length of cannula tip 40 pro~ectlon, in turn, dictates the depth of interior concavity 38 of projection 36 on the end wall 34 of the outer cap 12. The outer end of the distal tip 40 o' cannula 18 should bear against the inner surface Oc this projection 36 to minimize any possible treatment material loss during shipment or handling and before the outer cap 12 is removed, either by itself during partial insertlon, or with inner cap 1~ during full insertion.
.he two piece mastitis cannula cap in accordance with the psesent invention provides a safe, easy to use, accurately controilable and re?roducable, ,nexpensive means to ?ractice the partial cannula insertion techniaue which recent studies have suggested may be effective in the treatment of mastitis in dairy cows. At the same time, the two part cap structure affords the user an assembly which can be utilized for conventional full cannula insertion treatment, if desired. Thus the two part mastitis cannula cap of the present invention provides the freedo~ to select and use whichever of the two treatment procedures is deemed more desirable without sacrificing ease of use, d'sposability, and package integrity.

While a preferred embodiment of a two part mastitis cannula cap in accordance with the present invention has been set or~h 'ully and completely hereinabove, it will be obvious to one of skill in the art that a number of changes in, Lor example the size and shape of the syringe, the materials used for the syringe, cannula and cap, the overall length of the cannula and hence the overall length o' the two part cap and the li~e may be made without departing from the true sp~rit and scope of the 67 present invention which is accordingly to be limited only by the following claims.

Claims (11)

1. A two part mastitis cannula cap for facilitating the controllable length insertion of a mastitis infusion syringe cannula into the teat canal portion of a teat of a dairy cow, said cap comprising:

an inner cap including a first snap end having means to attach said inner cap to the syringe, a generally elongated tubular side wall, a relatively large diameter, generally planar distal end face which is joined to a distal end of said inner cap tubular side wall, said generally wide distal end face being sized to prevent insertion of said inner cap into the teat canal while serving to stabilize said inner cap distal end face against the end of the teat during partial cannula insertion, said distal end face of said inner cap having a relatively small, central aperture, said central aperture being sized to allow a distal tip portion of thecannula to extend through said aperture, said inner cap having a length relativeto the length of the mastitis infusion syringe cannula to allow said distal tip of the cannula to extend through said central aperture beyond said distal end face of said inner cap when said inner cap is attached to the syringe to thereby limit the length of said cannula which is exposed for insertion into the teat canal to a length less than the length of the teat canal; and an outer cap positionable about, and closely overlying said distal end of said inner cap, said outer cap having generally planar end wall including a central projection which forms an interior concavity that receives said cannula distal tip, said interior concavity and said cannula distal tip being cooperatively sized to form a snug, leak resistant interfit, and further including a generallytubular sidewall, said outer cap sidewall being sized to overlie said inner cap tubular side wall to removably secure said outer cap to said distal end of said inner cap.

2. The two part mastitis cannula cap of claim 1 wherein said distal end face has a diameter of generally between 5 mm and 7 mm.

3. The two part mastitis cannula cap of claim 2 wherein the length of said inner cap relative to the length of the cannula allows the distal tip of the cannula to extend through said aperture by only about 3 mm.

4. The two part mastitis cannula cap of claim 3 wherein said distal end face of said inner cap is joined to said inner cap tubular side wall at a rounded peripheral edge.

5. The two part mastitis cannula cap of claim 1 wherein said snap end of said inner cap includes a radially inwardly directed lip, said lip being receivable in an annular groove in the syringe and forming said means to attach said inner cap to the syringe.

6. The two part mastitis cannula cap of claim 1 wherein said outer cap includes an outwardly extending flange.

7. The two part mastitis cannula cap of claim 6 wherein said flange is secured to said sidewall of said outer cap.

8. The two part mastitis cannula cap of claim 1 wherein said inner tubular sidewall includes at least two spaced protrusions and further wherein said outer cap sidewall has a recess on an inner face thereof, said recess and said protrusions cooperating to secure said outer cap to said inner cap.

9. A two part mastitis cannula cap for facilitating controllable length insertion of a mastitis infusion syringe cannula into the teat canal portion of a teat of a dairy cow, said cap comprising:

an inner cap including a first end having means to removably attach said inner cap to the syringe, a generally elongated side wall and a second end having a distal end face with a diameter sized to prevent insertion of said inner cap into a teat canal while serving to stabilize said distal end face against the end of a teat during cannula insertion, said distal end face having an aperture for permitting a distal tip portion of the cannula to extend through said aperture, said inner cap having a length smaller than that of the cannula, the length of the distal tip portion extending through said aperture, when the inner cap is attached to the syringe, being less than the length of a teat canal;

an outer cap for covering a cannula distal tip extending through said aperture of said inner cap, said outer cap being removably secured to said innercap; and sealing means being provided in said cannula cap for preventing fluid leakage from said cannula cap;

whereby either the outer cap alone can be removed to expose the distal tip portion of the cannula or the outer and inner caps can be removed to expose the entire cannula.

10. The two part mastitis cannula cap of claim 9 wherein said outer cap includes an internal recess and wherein said sealing means is provided by forming walls of said recess to closely interfit with the distal tip of said cannula to create a leak-resistant closure for said cannula distal tip.

11. A method of selectively treating a dairy cow by partial or full insertion infusion of a bovine mastitis treatment medium, comprising the steps of:

providing a mastitis treatment syringe and cannula assembly containing a bovine mastitis treatment medium, said syringe and cannula assembly having a two part cannula cap including an inner cap and an outer cap secured to said inner cap, said inner cap having a length less than the length of a cannula and a distal end face through which the distal tip of the cannula projects;

selectively either (1) removing the outer cap and inserting the cannula tip into the end of a teat and into a teat canal of a dairy cow until the distal end face of the inner cap abuts the teat end, thereby placeing the cannula distal tip within the teat canal; or (2) removing both the outer cap and inner cap from the cannula and inserting the cannula tip into the end of a teat and through the teat canal of a dairy cow, thereby placing the cannula distal tip within theteat cistern of the dairy cow; and activating the syringe to infuse the mastitis treatment medium into the teat canal or teat cistern of the dairy cow.