Abstract:
The present invention is directed to methods for applying bovine foot and hoof treatment compositions having two or more specific and complimentary antimicrobial components in a hoof bath just prior to use to work more effectively. These antimicrobial components may include antimicrobial inorganic salts of certain heavy metals, cationic agents, peroxides, aldehydes, fatty acids, iodines or other suitable compounds effective in the killing of microorganisms.

Description:
[0001]     This application claims priority on Provisional Application No. 60/723,462 filed Oct. 4, 2005, the disclosure of which is incorporated by reference herein. 
     
    
     FIELD AND BACKGROUND OF THE INVENTION  
       [0002]     The present invention relates generally to hoof bath systems for dairy animals, and more particularly to a hoof bath system having in situ chemical mixing, chemical distribution for multiple hoof baths, and improved hoof bath components with improved hoof bath efficiency, efficacy, and automation.  
         [0003]     The present invention also relates generally to bovine hoof treatments, and more specifically to bovine hoof treatment compositions and methods having two or more separate components mixed at the dairy to improve efficacy and safety to humans and animals.  
         [0004]     Lameness is one of the major problems facing the dairy industry in the world today. The cost of lameness is measured by lost milk production, culled cows, dead cows, additional labor, vet bills, and medicines for treatment. In the U.S. alone, the cost of lameness has been reported to be between $300 and $412 per cow. With an overall estimated incidence rate of 10% to 15%, the annual overall cost of lameness would exceed 570 million dollars. It is especially a problem in large herds, which are the fastest growing segment of the market. The prevalence of lameness in large herds is 50% or more and is reflected by an annual incidence of 60% to 70%. Infectious diseases of the foot or hoof are one of the primary causes of lameness.  
         [0005]     Studies have showed that fully a third of all lameness in cows is caused by one disease, digital dermatitis. Digital dermatitis is present worldwide and is estimated to be present in 41% of herds smaller than 100 cows and from 64% to 82% in larger herds. Contagious and debilitating diseases of the bovine foot and hoof include such conditions as bovine hoof rot, digital dermatitis and interdigital dermatitis.  
         [0006]     Hoof baths containing germicidal/cleaning chemicals and antibiotics and/or other biologics have been used on dairy operations in the attempt to prevent, control and treat these diseases. Hoof baths are generally located in the return alley of dairy milking barns or parlors. After being milked, the animal will typically walk through the hoof bath on the way back to where they are housed. The feet and hooves will many times contain accumulated dirt and manure, even after milking when at times the feet and hooves are sprayed with water or diluted chemicals. This is especially true in modern dairy facilities with housing contained in limited areas such as free stall or tie stall barns or dry lots instead of open pasture.  
         [0007]     In addition, on passing through the hoof bath, the cows may defecate into the hoof bath. The added organic material or load to the hoof bath compromises the antimicrobial products&#39; ability to work in the disinfection and cleansing of the cow feet where the causative microorganisms are located. For economic reasons, the use of antibacterial chemical and biological products in doses high enough to compensate for the organic material present in the hoof bath and to penetrate through organic material and whatever tissue may conceal or otherwise harbor the bacterial pathogens, is usually cost prohibitive. Other chemical products that are less expensive to use at higher doses have the disadvantage in that they may be toxic to the animals, the people working in the dairy facilities or the environment.  
         [0008]     Also, many times when one product is used successfully (as in the treatment of digital dermatitis lesions) and the dose or frequency of the dose lessened after successfully eliminating the lesions, the clinical manifestations of the disease will reappear after a short time. One option utilized by many dairy producers is to alternate or rotate more than one chemical or antibiotic product at different times in the same hoof bath. There is at least anecdotal evidence that alternating different chemicals is effective in helping to reduce the incidence and prevalence of infectious diseases of the foot. However, this practice still does not compensate for the above-mentioned problems of using a high enough dose to overcome organic load while still producing a hoof bath that is safe and of low toxicity.  
         [0009]     Prior hoof baths were typically recessed into the exit alley and were filled by hand or remotely through a system of pumps, pipes and valves. Dairy operators monitored the baths to determine when fresh chemicals and water needed to be added to the bath. Fresh bath water and chemicals are needed as chemicals lose their efficacy and/or the bath becomes fouled with dirt, debris, and manure.  
         [0010]     To clear or flush dirt, debris, and manure from the baths, high pressure and high velocity water was pumped into the bath. Early hoof baths had an upstream end into which flushing water was pumped and a downstream end through which the flushing liquid and flushed materials flowed.  
         [0011]     The downstream ends in some hoof bath systems were simple curbs or walls over which the fluid and material is forced by water pressure and/or velocity. Such systems tend to waste water and require unnecessarily high pump pressure. In addition, the inherent nature of a fixed curb can prevent all of the debris from being flushed from the bath.  
         [0012]     Drains in the downstream end were added to some such systems to improve flushing performance. Some drains were manually operated, while others were automated to synchronize with flushing and re-filling operations.  
         [0013]     In an attempt to further improve flushing performance, at least one system attempted to create specific current flows in the bath during flushing operations by using nozzles of varying jet velocities, sizes, and arrangements. See Vander Veen, U.S. Pat. No. 6,739,286. Such precision is difficult to maintain in actual dairy environments that are subject to harsh conditions, extreme temperature changes, and damage from animals.  
         [0014]     As stated above, some hoof bath systems mix chemical and water in the bath. See Vander Veen, U.S. Pat. No. 6,739,286, for example. Such systems can be effective when a single hoof bath is used in a dairy, but using separate chemical and water dispensers in more than one hoof bath unnecessarily complicates piping, pumps, and valves. Duplicate dispensing systems also add expense in building and monitoring such systems. Malfunctions in such duplicative and complicated systems are inevitable.  
         [0015]     Accordingly, there is a need for another way to bring safe, efficacious and cost effective doses of these products to the site of the microbial pathogens on the animal without being unduly hindered by organic material that may be present in the bath or on the foot. In addition, there is a need for a system-wide approach for operating hoof baths that reduces initial capital and maintenance expense.  
       SUMMARY OF THE INVENTION  
       [0016]     A hoof bath system for dairy animals, the system comprising: an in situ chemical mixer; a water supply; a chemical and water mixer for receiving chemicals from the in situ chemical mixer and the water supply; a chemical and water distributor for distributing chemicals and water from the chemical and water mixer; a plurality of hoof baths for selectively receiving a mixture of chemicals and water from the chemical and water distributor; a bath flusher for receiving water from the water supply, the bath flusher for forcing water through the bath; and a system controller for synchronizing the chemical and water distributor and the bath flusher to flush the plurality of baths and refill the baths with a chemical and water mix.  
         [0017]     The present invention also is directed to compositions and methods for combining or mixing compositions having two or more specific and complimentary antimicrobial components in a hoof bath just prior to use. Certain germicides when combined, act synergistically in such a way as to increase the efficacy of one or both of the germicides, as is the case with hydrogen peroxide and such germicidal inorganic salts as copper. In order for to gain maximum antimicrobial efficacy, the combined germicides must be used as soon as possible after combining before one or both of the germicides are used up due to oxidation or other type reactions with the other component. These components include one or more of certain antimicrobial salts of certain heavy metals including copper sulfate, copper acetate, copper formate, copper bromate, copper trichloroacetate, zinc sulfate, zinc acetate, zinc formate, zinc bromate or iron sulfate, iron acetate, iron formate, iron bromate or other heavy metal salts not listed. These components can also include such aldehydes as formaldehyde, gluteraldehyde or glycoxyaldehyde.  
         [0018]     A second group of antimicrobial components should be mixed with the first to achieve the objectives of this invention. This second group can include quaternary ammonium compounds, such as monoalkyltrimethyl or triethylammonium salts such as monoalkyltrimethylammonium chloride, monoalkyldimethyl or monoalkyldimethyl-substituted benzylammonium salts, heteroaromatic ammonium salts, dialkyldimethylammonium salts, bis-quaternary ammonium salts, polysubstituted quaternary ammoniums salts and polymeric quaternary ammonium salts.  
         [0019]     The second group can also include such inorganic peroxides such as hydrogen peroxide or persulfates, perborates, per carbonates and sodium peroxide, and organic peroxides such as peroxyacetic acid, or others such as other peroxy acids, cumene peroxide, hydroperoxides, diacyl peroxides and peroxyesters.  
         [0020]     Sulfonic acids or sulfates can also be combined into the hoof bath and may include: dodecylbenzene sulfonic acid, sodium sulfanated oleic acid, sodium 1-octane sulfonate, sulfonated 9-ocatedceonic acid, sodium xylene sulfonate, dodecyldiphenyloxide disulfonic acid, sulfonated tall oil fatty acid, sodium naphtallene-sulfonic acid and 1-octane sulfonic acid.  
         [0021]     Medium chain carboxylic fatty acids may also be added to the hoof bath and these may include: caproic, or hexanoic acid, heptanoic acid, caprylic or octanoic acid, nonanoic acid, capric or decanoic acid, lauric acid, myristic acid linoleic acid or linolenic acid or their esters such as methyl caprylate, methyl caprate, methyl laurate, lauryl acetate, glycerol monolaurate and amides of fatty acids, such as lauryl methylamide and dodecylamine.  
         [0022]     The composition also might include raw elemental iodine and complexed iodinated compounds or iodophors. Carriers might include such surfactants as nonyl phenol ethoxylates, linear alcohol ehtoxylates, block co-polymers, or such polymers as polyvinylpyrridone (PVP).  
         [0023]     The composition may also include chlorinated compounds such as chlorine dioxide or stabilized chlorine dioxide, salts of chlorine (sodium chorite) or organic chlorinated compounds (chloroisocyanurate), Phenolic compounds such as phenol and pheonlic esters of p-hydrobenzoic acid (methylparaben, propylparaben) may also be included in the second group of the composition.  
         [0024]     All of the components in each group could be used in any combination and number of ingredients as long as there are at least two (at least one from each group) are being used at any one time. Each of these components can be used in any quantity or concentration as long as the concentration does not interfere or prevent another of these components from being added so that at least two compounds are able to be mixed at the site of use.  
         [0025]     In addition to these components, there could be pre-added or added at the site at any concentration such components as acids including either organic acids such as acid, citric acid, acetic acid, inorganic acids such as phosphoric acid, sulfuric acid, nitric acid, surfactants, stabilizers, chelating agents, emulsifiers, thickeners, dyes and fragrances.  
         [0026]     One advantage of combining two or more of the aforementioned antimicrobial hoof bath ingredients may be an increase in the ability to kill or inhibit disease-causing microorganisms. The killing action may be synergistic or merely additive, but in any case, will be better than using more of just component alone. These advantages, as conceived on a dairy operation, may be an increased killing rate, greater resistance to the effects of organic load, less toxicity from the chemicals and lower costs. If the action is synergistic, the most important advantage is that the combined mixture will chemically have an increased bactericidal efficacy against the disease pathogen than the sum of the parts would alone. If additive, the previously mentioned advantages by combining, for example, a more toxic but lower cost chemical with a less toxic one that costs more. In this case, toxicity will be avoided by combining the two instead of using more of the toxic chemical alone and some costs savings will be achieved by using the mixture instead of using just more of costlier component.  
         [0027]     Some manufacturers have combined various types of anti-foot disease chemicals or biologics and sold them as a ready-to-use pre-mixed product. This approach entails certain advantages such as a lack of stability that occurs when certain chemicals or biologics are combined. The previously mentioned combination of an inorganic salt combined with peroxide is a good example. The peroxide component will then oxidize quickly and after a relatively short period of time be rendered ineffective. Additional problems of storage or transport may occur if the combined constituents produce a mixture that may be volatile causing the release of gas at higher temperatures, which may therefore increase the risk of leaking or explosion if the containers are not properly vented. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0028]      FIG. 1  is a schematic view of a hoof bath system in accordance with the present invention;  
         [0029]      FIG. 2  is a schematic plan view of a hoof bath system in accordance with the present invention;  
         [0030]      FIG. 3  is a schematic plan view of a hoof bath system in accordance with the present invention having a pair of baths in a series arrangement;  
         [0031]      FIG. 4  is a schematic plan view of a hoof bath system in accordance with the present invention having a pair of baths in a parallel arrangement;  
         [0032]      FIG. 5  is a schematic plan view of a hoof bath system having two lanes of baths in series;  
         [0033]      FIG. 6  is a schematic plan view of a hoof bath system having two lanes of baths in series and having a chemical powder mixer/dispenser;  
         [0034]      FIG. 7  is an elevational view of a control panel for use in a hoof bath system in accordance with the present invention;  
         [0035]      FIG. 8  is a cover panel for the control panel of  FIG. 7 ;  
         [0036]      FIG. 9  is a perspective view of a hoof bath in accordance with the present invention;  
         [0037]      FIG. 10  is a cross-sectional perspective view of a hoof bath in accordance with the present invention;  
         [0038]      FIG. 11  is an elevational view of a pneumatic bladder in a deflated position to drain fluid from a hoof bath in accordance with the present invention;  
         [0039]      FIG. 12  is an elevational view of the pneumatic bladder of  FIG. 11  in an inflated position to retain fluid in a hoof bath;  
         [0040]      FIG. 13  is a perspective view of an angled hoof bath upstream end;  
         [0041]      FIG. 14  is a control panel for a hoof bath system having an operator-controlled pneumatic bladder valve;  
         [0042]      FIG. 15  is an elevational view of chemical powder mixing canisters in accordance with the present invention;  
         [0043]      FIG. 16  is a suitable programming sequence for use in a hoof bath system in accordance with the present invention; and  
         [0044]      FIG. 17  is a PLC cycle chart for use in a hoof bath system in accordance with the present invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0045]     In the following detailed description of the preferred embodiments, the same reference numeral will be used to identify the same or similar feature in each of the figures.  
         [0046]      FIG. 1  is a schematic view of a hoof bath system  40  in accordance with the present invention, including a controller  42 , a water supply  44 , an air supply  46 , a powder chemical dispenser  48 , a liquid chemical dispenser  50 , a pumping station  52 , a water and chemical distribution network  54 , and a control valve system  56 . These components feed at least one hoof bath  60  as illustrated in  FIG. 2 . Also used in the system  40  is a drain  62 .  
         [0047]     The hoof bath system  40  provides a useful automated or semi-automated system for controlling hoof diseases in dairy animals by directing animals through at least one hoof bath  60  in which water and/or hoof treatment chemicals are disposed. The animal&#39;s hooves are thereby cleaned of a substantial amount of soil, such as dirt and manure. The chemicals can provide prevention or treatment of diseases that affect hooves.  
         [0048]     The controller  42  can be any kind of programmable or manual controller of valves, pumps, drains and dispensers. Preferably, the controller  42  is programmable and fully automated to relieve a dairy operator from devoting valuable time and energy to hoof bath operation. The controller  42  can be any type of computer or printed circuit board. It can have the ability to receive various controlling operations and to receive data regarding hoof health for the dairy animals so that chemical type and quantity are automatically dispensed to address specific herd health needs.  
         [0049]     In addition, flushing and re-filling frequency can be manually or automatically adjusted based on these factors. Finally, even when automation is not desired or feasible, the controller  42  can notify a dairy operator of conditions, flushing or re-filling operations, etc. so that the system  40  need not be monitored consistently.  
         [0050]     The water supply  44  can be any standard water supply system for a dairy and need not supply potable water. Similarly, the air supply  46  is standard, but could be used to provide special gases necessary for mixing with chemicals. Suitable water filters  66  and air filters  68  are desirable.  
         [0051]     In the present invention, both powder and liquid forms of chemicals can be used. It is desirable to use powder chemicals for reduced expense and increased shelf-life, but conditions and chemical types may control which type or combinations of chemicals are appropriate under given circumstances.  
         [0052]     In the illustrated embodiment, powder chemical dispensers  48  are arranged in a pipe and valve network  70 . Four canisters  72  are illustrated in  FIG. 1  (and two are illustrated in  FIG. 15 ), but one or more canisters could be used. Preferably, each individual canister  72  is partially filled with powdered chemicals  74  and then filled with a liquid mixing agent such as water or other liquid chemical. Each canister  72  is then filled with enough mixed chemical to supply an individual hoof bath. In this example, the appropriate amount of chemical is provided without complexing, mixing or metering from a bulk container.  
         [0053]     Each canister—preferably is sized to receive enough powdered chemical to treat 150 to 200 cows depending upon soil load, chemical strength, and other factors. There can be multiple canisters to receive extra powdered chemical volume or a variety of chemicals. One canister is used each time a bath  60  is filled.  
         [0054]     Once each canister is filled with powdered chemical it is filled with an appropriate amount of water to form a liquid solution. This solution can be concentrated to mix with more water prior to being added to the bath or in the bath itself, or the solution can be diluted to the proper amount in the canister.  
         [0055]     The canisters are provided with fill valves  73  for the water or other liquid that will be mixed with the powdered chemical. The liquid may itself be a liquid chemical solution so that the combination of liquid chemical and powdered chemical provides an efficacious mixture of chemicals that need not have a long shelf-life prior to use in the bath. In this manner, varying chemical doses, mixtures and types is easily performed to obtain a highly effective hoof bath treatment chemical in an efficient and automated system  40 .  
         [0056]     Each canister also preferably includes a proximity sensor (not illustrated) that identifies the presence of powdered chemical or whether the canister is even closed properly. If neither of these conditions is met the canister will not fill with liquid, which could cause a spill.  
         [0057]     Instead of, or in addition to the canister, the system may include mechanisms for injecting ozone (O 3 ) into the bath to disinfect the bath  60  and various pipes, nozzles, etc. in the chemical and/or water distribution system. No sanitizing chemicals may be necessary if this approach were used.  
         [0058]     The individual canisters  72  can be filled by an operator or automatically by a bulk feed system  76 . ( FIG. 18 .) The bulk feed system  76  includes a hopper  78  for receiving large loads of powdered chemical. An auger  80  in the hopper bottom moves chemical to a distribution shoot and then to individual canisters  72 . When large containers (not illustrated) are used to mix powdered chemicals prior to use in the hoof baths, the bulk feed system  76  can be used to provide any desired amount of powder to the mixing container. Alternately, an adductor could be used to siphon chemical powder from a storage bin or hopper  78 , which uses a venturi induced vacuum to carry chemical powder to a mixing canister or directly to a pipe in which the chemicals are mixed into solution.  
         [0059]     The liquid chemical dispensers  50  can be used to store powdered chemicals after they have been mixed with water or to store liquid chemicals purchased in that form. They can be pumped into the water and chemical distribution system  54  as needed or in total, depending upon their capacity.  
         [0060]     The chemicals in liquid form are pumped to the hoof baths  60  via the pumping station  60  through the water and chemical distribution network  54 . The controller  42  can be used in conjunction with the pumping station  52  to pump only water from the water supply  44 , only chemicals, or a mixture of the two, based on the operation stage of the hoof bath  60 .  
         [0061]     In addition, the controller  42  ( FIG. 1 ) can be used to alternately operate the control valve system  56  to feed water, chemicals, and mixtures thereof to select hoof baths  60  when more than one are present.  
         [0062]     In the present hoof bath system  40 , any type or size of hoof bath can be used, and in particular a number of any such hoof baths can benefit from the system of the present invention. Nonetheless, a preferred hoof bath  60  is illustrated in  FIGS. 2 through 6  and  FIGS. 9 through 13 .  
         [0063]     As depicted, each hoof bath  60  is disposed in a walkway that controls animal movement and requires each animal to walk through the bath  60 . Despite being forced to walk through the bath  60 , its configuration in accordance with the present invention is preferably raised above the walkway for ease of installation and maintenance. Ramps or platforms (not illustrated) are provided for the animals.  
         [0064]     Each bath  60  is generally longer than it is wide and has an upstream end  90 , a downstream end  92 , and sides  94 . The upstream end  90  is disposed at an angle, approximately 45° in the illustrated embodiments, to the walkway so that the animals can step into the bath  60  without breaking stride. This arrangement is important to dairy efficiency because it keeps animals moving with minimal congestion and it keeps the animals comfortable.  
         [0065]     Each lane is preferably sloped downward so that water and other liquids and soils flow in the same direction as cow traffic. The angled upstream end  90  of the bath therefore redirects the flow to the side so that it does not flow into the bath  60 . In addition, a lip extending upstream away from the upstream end  90  of the bath  60  prevents higher velocity lane drainage from flowing into the bath.  
         [0066]     In addition, the bath  60  is preferably dimensioned so that each animal hoof takes at least two steps in the bath  60  such that a preferred bath length is 108″. Such a dimension improves overall bath performance by ensuring adequate rinsing and chemical treatment of each animal hoof. The bath  60  may also include gradations in the side walls to indicate the volume or depth of fluid in the bath  60  for operator inspection.  
         [0067]     With typical soil loads, a hoof bath  60  in accordance with the present invention will require flushing every 150 to 200 animals being treated. A dairy operator can monitor this number and flush the hoof bath  60  or the flush can be automated.  
         [0068]     When automated, the flushing operation can be initiated in several ways. One option is to automatically count cows as they pass through the bath  60  with either a proximity sensor or a wand switch (not illustrated) mounted in the lane. Counting cows automatically is a reliable way to ensure cleanliness of the bath  60  and efficacy of bath chemicals.  
         [0069]     Another option is to initiate flushing in conjunction with the milking operation because the hoof bath  60  will typically be placed near a milking parlor exit. The bath  60  can be flushed and refilled at the start of milking by using one or more cow sensors in the milking parlor, for example. Another option is to initiate flushing at a predetermined time after the end of milking as sensed by the milker units. Refilling the bath  60  can then take place when the sensor senses the milker unit back in operation. In that way, the bath  60  will be filled shortly before the cow arrives.  
         [0070]     Another option flushes and refills each bath  60  when the sensor signals an end to the milking cycle, provides a lag time for the last cow to move out of the parlor and through the bath  60 , and then flushes and refills the bath in time for the next milking operation. Obviously, the number of cows, the frequency of milking, the shelf-life of treatment chemicals, bath soil loads, and other environmental conditions will be factors in determining when and how often the bath  60  needs to be flushed and refilled. The automated controller  42  is preferably programmable by the dairy operator to accommodate each particular dairy&#39;s varying needs.  
         [0071]     In  FIG. 3 , there is an upstream bath  60  and downstream bath  61  in series, which requires each animal to walk through both baths  60 . In this arrangement, an upstream bath  60  can be used to rinse and clean the animal hooves, while the downstream bath  61  is used to treat the hooves. In such an arrangement, the upstream bath  60  may be water alone or include chemicals useful in cleaning hooves. In the downstream bath  61 , medicines or other chemical treatments can be used.  
         [0072]     The two baths  60 ,  61  are preferably fed from the same water and chemical distribution network  54  with the control valve system  56  and controller  42  working in conjunction to feed appropriate flushing, water, and treatment chemicals to each bath.  
         [0073]     Similarly, the hoof bath system  40  may include a pair of baths  60  in a parallel arrangement, as illustrated in  FIG. 4 . With such an arrangement, two lanes of animal traffic can be accommodated as described above in reference to  FIG. 2 . In this arrangement, the controller  42  and control valve system  56  feed each bath  60  and  61 . Each bath can receive the same water and chemical combinations, or each bath may receive different chemical and water solutions to treat animals in each lane differently. For example, animals with hoof diseases can be controlled through one lane for intensive treatment while other healthier animals are controlled through the other lane.  
         [0074]     A combination of series baths from  FIG. 3  and parallel baths from  FIG. 4  are illustrated if  FIG. 5  so that any desired form of pre-treatment and treatment can be used.  
         [0075]     In  FIG. 6 , there is a system  40  similar to the system  40  in  FIG. 5  except that the upstream baths  60  are fed by a first controller  42  and control valve system  56  and the downstream baths  61  are fed from a separate controller  43  and control valve system  57 . The second controller  43  may be used in situations when chemicals are only fed to the downstream baths  61  and not the upstream baths  60 .  
         [0076]      FIGS. 7 and 15  illustrate a control panel  100  that is at least part of the controller  42 . The controller  42  may include computers and other control panels as well. The control panel  100  illustrated includes a PLC control, switching for purge air regulators  102 , bladder air regulator  104 , pump air regulator  106 , a water meter  108 , and liquid chemical pumps  110 . With such an arrangement in the control panel  100 , an operator can monitor and operate the hoof bath system  40  of the present invention at any location.  
         [0077]      FIG. 8  simply illustrates the cover  112  for the control panel including a main power on/off switch  114 , chemical and water control switches  116 , automatic stop/flush switch  118  for a first bath, a similar switch  120  for a second bath, and a display  121 .  
         [0078]     More detailed illustrations of the hoof bath  60  appear in  FIGS. 9 through 13 . In  FIG. 9  the bath  60  includes the upstream end  90 , downstream end  92 , and sides  94  as generally described above.  
         [0079]     The bath  60  is preferably made of heavy-duty cross-linked polyethylene plastic, but other materials can be used as well. In addition, a rubber mat  128  is disposed in the bottom for better footing. The mat  128  can be replaced with other similar mats or mats of differing properties as weather and bath soil conditions vary.  
         [0080]     The upstream end  90  includes a liquid distribution manifold  130  that injects water and chemicals into the bath  60 . Disposing the manifold  130  in this location is desirable because animals are less likely to kick and damage the manifold  130 .  
         [0081]     The manifold  130  includes orifices  132  through which liquid flows. ( FIG. 9 ). At alternating times, there may be water only, chemical only, or mixtures thereof flowing out of the manifold orifices  132 . The orifices are arranged downstream toward the downstream end  92  of the bath  60  despite the fact that they are disposed in the angled upstream end  90  of the bath  60 . Side baffles  133  extending inwardly from the sidewalls  94  can be used to reduce some splashing from the manifold  130  injections.  
         [0082]     In the preferred embodiment, the downstream end  92  of the bath  60  includes a pneumatic bladder “gate”  140  that is inflated to close off the downstream end  92  ( FIG. 12 ) and thereby retain fluid in the bath  60 . The bladder  140  is deflated to release fluid and debris from the bath  60  ( FIG. 11 ). The pneumatic bladder  140  provides a superior seal against leakage as compared to moving plates and is less likely to clog than a drain or valve arrangement.  
         [0083]     By simply deflating the bladder  140  ( FIG. 11 ), liquid in the bath  60  can drain or be flushed by water from the liquid distribution manifold  130 . The bladder  140  is less likely to be damaged by animals. Further, when the bladder  140  is re-inflated after flushing ( FIG. 12 ), it can conform to the shape of obstacles or debris that was not completely flushed from the bath  60 . This is not necessarily possible with a moving plate, drain, or valve that could be used in place of the bladder  140 .  
         [0084]      FIG. 10  illustrates further details of the hoof bath  60 , including a stainless steel protective cover  150  for protecting the manifold  130 . If desired, the mat  142  can be secured to the bath  60  using stainless steel fittings  151 .  
         [0085]      FIGS. 11 and 12  illustrate the bladder  140  in the opened and closed positions, respectively. The bladder  140  in the opened position opens up nearly the entire width of the bath downstream end  92  to improve drainage and complete flushing of soil and debris from the bath  60 .  
         [0086]     In the inflated position, a mere nine pounds per square inch (9 psi) is adequate to seal the downstream end  92  of the bath  60 .  
         [0087]     The bladder  140  can be operated with manual switches and pumps or it can be operated automatically by the controller  42 .  
         [0088]      FIG. 16  illustrates a suitable programming schedule  200  and  FIG. 17  illustrates a suitable cycle chart  210  for use in a hoof bath system  40  in accordance with the present invention.  
         [0089]     One purpose of the present system is directed to compositions and methods for mixing certain, specific and known antimicrobial components at the site of the hoof bath just prior to use by the cows. This invention enables a dairy farmer in the control of contagious diseases of the bovine foot while increasing cost savings and increasing safety to humans and animals. Evidence in the laboratory and in the field supports these contentions especially as it relates to bactericidal efficacy. It also lessens the problems associated with pre-mixing ingredients such as stability and safety in storage and transport.  
         [0090]     The antimicrobial hoof bath chemicals and biologics are combined at the site of the hoof bath just prior to use. These components can be solid, liquid or both combined. They can be dispensed manually or by systems presently developed or in development that dispense the chemicals automatically into the hoof bath via pipes or hoses (for liquids) or automated hoppers (for solids). These devices can be set to dispense at pre-determined intervals based on time or number of cows and thereupon dispense a pre-set amount of chemicals along with water to achieve the desired dilution rate.  
         [0091]     Prior to the addition of new chemical(s), the old, used solution along with contaminating manure or soil can be forced out or flushed automatically out of the hoof bath into a drain. The present invention of mixing components at site provides the greatest benefit when used with an automated system although it can also be practiced manually.  
         [0092]     One example utilizing an automated flushing hoof bath entails adding, at specified intervals, pre-diluted copper sulfate, pre-diluted quatemary ammonium compound and pre-diluted hydrogen peroxide and water where the final concentration of each component would be 2% by volume. This would provide advantages over using only one of these compounds, even at a higher concentration or using them alternatively at different times or pre-mixing them at a considerable time prior to use (i.e.: time of manufacture).  
         [0093]     The advantages would include cost savings by using less chemical and less labor to apply chemical to the hoof bath or utilize less storage space because lower amounts of the bulkier products can be used. Efficacy advantages would be expected with a greater reduction or lower rate of infection of the aforementioned foot/hoof diseases. Automated systems ensure that the chemicals or biologics are at the doses specified since the chance of degradation of components (such as the hydrogen peroxide) would be lessened if they are not mixed a significant time prior to use.  
         [0094]     The present invention in its preferred embodiments described herein conserves water by using fewer than ten gallons of flushing liquid; has chemical resistant and durable high-strength plastic construction; utilizes a large drainage zone sealed by an effective bladder to seal the drainage zone; has a longer (108″) length that assures double treatment (two steps) of rear hooves; is automated to reduce operation interaction if desired; is programmable as dairy conditions change; accurately mixes treatment chemicals; optionally mixes a variety of chemicals that have higher potency but possibly short shelf-life; and has an automated flush and refill option that can be activated by an operator, cow counts, or milking equipment activation/deactivation. The result is a cost-effective and efficacious hoof treatment system.  
         [0095]     The foregoing detailed description of the present invention is provided for clearness of understanding only. No unnecessary limitations therefore should be read into the following claims.