This invention relates to a method of applying foot or hoof sanitizing type solutions to the feet of animals where the solutions are consistently maintained at an efficacious level over time. Additionally, this invention relates to a device that enables the maintenance of such an efficacious level.
For years, directing walking animals through foot baths containing foot or hoof care solutions has been practiced as an aid to general foot or hoof health or for the prevention of, and a cure for, diseases of the animals' feet or hooves. Materials used for these solutions included (and include) copper sulfate, zinc sulfate, formaldehyde, and certain antibiotics. Additionally, several over the counter commercially compounded liquid products have been and are being used. Major manufacturers of this latter category are Delaval (DoubleAction), Westfalia-Surge (Pedicure Rx), and SSI Corporation (Healthy Foot).
The foot baths used were typically constructed of wood, metal, or plastic/fiberglass materials. The dimensions of these foot baths had varying lengths, widths and depths and were constructed to be sealed so that the foot or hoof care solution did not leak out of the foot bath. An example of typical foot bath constructive design resembles an “open topped box” that is 6 feet long, 32 inches wide, and six inches deep with a closed and sealed bottom. The depth of the water and foot or hoof care solutions held in the foot bath varied depending on the operator's preference. Today, the basic design of most foot baths remains the same.
Foot baths are inefficient and costly for several reasons.
As the animals enter the foot bath, there is a high probability that manure attached to the animals' hooves will be carried into the foot bath or that the animal will defecate into the foot bath solution. Additionally, depending upon environmental conditions, the animals may also have layers of mud and dirt clinging to the feet. Foot baths are liquid filled reservoirs that retain all environmental contaminants deposited in them. The manure or combination of manure and mud/dirt or organics rapidly degrades the foot bath solution and renders it ineffective.
Most commercially available foot or hoof care products degrade in the presence of organic contamination. This organic contamination offers challenges to most foot or hoof care materials which have been added to the bath for their intended purpose. The rate of degradation increases as more and more organic material is deposited into the foot bath, and often this degradation is exacerbated by the length of time that the foot or hoof care material is exposed to the organics. As contamination in the foot bath increases, the efficacy of the foot or hoof care material is eventually reduced to a point where the foot bath becomes inefficacious and must be evacuated and cleaned.
Traditionally, the manner of evacuating the foot bath relied on the operator picking up one end of the bath and dumping the contents on the floor or removing a drain plug which had been fabricated into one end and then allowing the spent solution to drain onto the floor. Cleaning of the foot bath relied on a worker cleaning it out with a hose and water. This method of evacuation and cleaning is still common today.
Charging the foot bath with a new foot or hoof care solution involved filling the bath with clean water, adding the foot or hoof care material to the bath, and then stirring or agitating the bath contents so that the foot or hoof care material was put into adequate solution. Alternatively, the foot or hoof care compound was added before or during the water addition stage and the action of the water filling the bath provided the agitation required to provide proper mixing. These practices are still widely used today.
Unfortunately, evacuating and cleaning foot baths is an unpleasant job. It is time consuming, and the individual performing the task is required to work closely with a solution laden with animal fecal matter. As a result, foot bath management is often avoided by not only workers but also by owners of the animal operation.
Additionally, the properly regimented use of a foot bath as a prophylaxis in prevention of foot or hoof disease is not always appreciated and sometimes simply is not possible. The impossibility is most generally present in high production dairy facilities where cows are always present in the area where foot baths are located and workers simply can not enter the area (either safely or actually or because of production time constraints) to perform the evacuation, cleaning, and refilling steps required. Accordingly, foot baths are not always used as frequently as they should be.
Finally, a lack of understanding on the part of owners and workers regarding the need to frequently evacuate, clean, and recharge foot baths to maintain efficaciousness often resulted in substandard achievement of the results intended to be achieved in the use of the foot bath. As such and as a result of one or more of the foregoing factors, several companies have recently developed “automatic foot baths”. The intention of these inventions has been to overcome the foregoing reasons for failure which have, as their root cause, the “human interface” in the foot bath operation and maintenance process.
Essentially, these automatic baths automatically evacuate, clean, and refill themselves. Typically, automatic evacuation is accomplished by an automatic drain valve (or other device) opening at a predetermined time or at predetermined time intervals and allowing the contents of the foot bath to completely drain onto the floor. Once drained, automatic foot baths then cycle into a “cleaning mode”.
Any organic material remaining in the foot bath after draining is then flushed out with one or more spray nozzles which are mounted within the foot bath and connected to a water source. The flush water is allowed to flow when a valve between the water source and the nozzle(s) is opened. The opening of the valve is automatic and its opening is activated using a control which sends the opening signal based on time or some other metric. Typically, the valves referred to herein are automatically controlled through a solenoid or other device which enables programmable and automatic opening and closing of valves.
Once the foot bath has been adequately flushed and cleaned, the drain valve (or other device) closes and the foot bath is refilled with water and a foot or hoof care solution. The source for the water used for refilling may be the same source as that used for flushing or a separate source where the actuation and termination of flow is effected by a separate solenoid valve. A foot or hoof care material is typically injected into the water source used to refill the foot bath but may instead be added via a dedicated plumbing circuit.
Once the foot bath has been filled with the foot or hoof care solution, it is then ready to treat more animals. After filling, and once the predetermined time has passed, the controls of the automatic foot bath then repeat the actuation of the drain, clean, and refill cycles. Generally, depending on the volume of foot or hoof care solution contained in the foot bath and the type and/or strength of the foot or hoof care material used, the number of animals that will walk through the foot bath between the initial filling (or refilling) and draining is typically from 125 to 500 cows.
While the automatic foot baths available today deliver some distinct advantages when it comes to labor savings, reduction of management (human interface) issues, and repeatability of performance, they still share a common disadvantage with manually operated foot baths. That is, the operations of both the manual and automatic versions of foot baths are suboptimal chemically speaking. Like a manual foot bath, they work on a “batch” basis. That is, the foot bath is “made up” for treating a finite number of animals such as milk cows. This batch basis operation leads to several disadvantageous characteristics.
First, because of the contamination issues herein previously cited, the amount of foot or hoof care material initially added to the foot bath must contemplate the degradation of that material if the foot bath is to have the level or proper concentration of active foot or hoof care solution present when the last animal intended to be treated walks through the bath. In other words, the solution of foot or hoof care material must be stronger than required for the first animals walking through the bath since the materials will degrade in the presence of organics and the solution must still be sufficiently strong to be efficacious for the last animal through the bath.
The foregoing phenomenon is depicted on Table 1. below. (Since with many hoof care chemicals an acidic condition is required, the pH level of the foot bath at any point in time predicts effective solution strength. In this regard, the pH level of the bath is also an effective prediction of efficacy.)
In this test, 50 gallons of water and 1.25 gallons of a commercially available acid based hoof care chemical were mixed in the foot bath. pH readings were taken at 1 hour intervals until 200 cows had passed through the foot bath. The data were generated at 1,600 cow dairy in Tulare County, Calif. In sum, at the start, the pH registered 0.8 and after 5 hours the pH had reached a pH of 6.2. At 10 hours, the pH had risen to 6.8. By hour 2 the organic contamination in the bath was decidedly noticeable. Large amounts of undigested fiber, having separated from deposited fecal matter, were observed floating in the bath. By hour 4, the accumulation of deposited fecal matter had noticeably thickened the foot bath solutions consistency. By hour 6, the foot bath had the consistency of a viscous sludge.
TABLE 11,600 Cow Dairy: pH Response Using Current Art of MakingOne Water & One Chemical Additon to Foot Bath
In a separate test at this same dairy, the label instructions of the commercially available, acid based hoof care chemical were followed. To a clean 50 gallon foot bath, ¾ of a gallon of the hoof care chemical was added and pH readings of the foot bath were taken once per hour until the label recommended level of 200 cows had walked through the foot bath. For purposes of determining predictable efficacy, the traditional industry standard for bactericidal activity (pH 4) was used. Table 2. below depicts the results of that test.
TABLE 21,600 Cow Dairy: Chemical Addition to Achieve RequiredpH at Last of 200 Cows Through Foot Bath
In this test, the pH at the beginning of the test was 1.2. At the end of the test, the pH was 5.1. Assuring the traditional industry standard is correct, approximately 80% of the cows first passing through the bath would have received an efficacious treatment and the last 20% of the cows passing would have received an inefficacious treatment.
Logically, it is the animals with foot or hoof problems that can most benefit from the strongest foot or hoof care solution. Unfortunately, it is these animals which most generally walk through the bath last. This is true simply because these animals' feet hurt and they therefore walk more slowly than their pen mates with healthy feet or hooves.
Thus, the healthy pen mates reach the foot bath first and begin depositing organic material therein, thereby degrading it. The “solution strength curve” that results from the current batch method of managing foot baths is precisely the opposite of what it should be in the context of animal foot or hoof health and the order in which animals pass through the foot bath. That is, animals with foot or hoof problems should be walking through the strongest strength solution and while those animals without problems could conceivably afford to be walking through the foot bath last when solution strength is degraded.
Second, because of the degradation curve, more foot or hoof care material must be used in a foot bath than would be required if the foot or hoof care solutions did not degrade or the solution strength could be maintained at a constant level over the period animals were walking through it. For this reason, in an effort to control costs, owners of these foot baths often operate these foot baths less frequently than may be required to maintain optimal foot or hoof health for the animal.
Finally, in high production operations, the automated evacuation, cleaning, and refilling cycles often take place while animals are passing through the foot bath. The result is that during this cleaning cycle period the animals passing through the bath are not being treated as intended.
In summary, even though automation of the dump, fill and dosage cycle has contributed to the management considerations of the foot bath, like traditional foot baths, the cost and efficacy of the foot bath solution throughout the use period of the solution has not been improved. Improper management, organic considerations, improper use of treatment and prevention products, and the tendency for target animals to be the last through the foot bath, all greatly reduce the efficacy and cost effectiveness of foot baths.
Therefore, there is a great need for a method to provide more effective application of foot disease treatment solutions that mitigate the degrading effect of organic contaminants introduced into the foot bath solution. Also needed is a method providing a device to facilitate the method and reduce costs of operation while providing low maintenance and ease of use for owners. Additionally needed is a method that enables animals to walk through the foot bath during its normal maintenance and which insures that all animals are treated as intended.