AU2013101672A4 - A formulation for topical administration and a method of its use - Google Patents

Abstract

Abstract: The present invention relates to the preparation and use of a topical formulation, to be applied as a spray to the skin for treatment or maintenance, wherein the formulation comprises a diluent, an emollient and an organic anti-microbial active.

Description

A FORMULATION FOR TOPICAL ADMINISTRATION AND A METHOD OF ITS USE TECHNICAL FIELD The present invention relates to a formulation for topical administration. The invention has particular application to the preparation and use of a topical formulation to be applied as a spray to the skin for treatment or maintenance. BACKGROUND ART Dairying is a significant primary industry in New Zealand, and significant investment is made in ensuring the health and wellbeing of dairy cows. The health of a cow can affect its productivity. One common issue that arises in the management of dairy cows is the condition of the skin of the teats of the dairy cow. The skin acts as a barrier to moisture and pathogens. The skin barrier protects the internal environment of the body from excessive absorption of water and other solutes that may be found in the environment. The skin of the teats of dairy cows can become damaged as a result of machine milking. The use of pulsating teat cups in machine milking can result in some minor skin trauma such as abrasions, grazes and blisters. Such trauma, if left untreated, can result in ischaemia and ulceration of the skin. Furthermore, in the field, the teats are often exposed to moisture and other pathogens. This is particularly the case during the wet spring months of the milking season. Prolonged exposure to moisture and detritus on the teats can result in the loss of natural secretions, such as glycerol, which are expressed from the sebaceous glands of hair follicles onto the skin. Glycerol assists in the hydration of the skin which is important to its function as a barrier. The loss of such secretions can disrupt the function of the moisture barrier of the skin, leading to an increased susceptibility to infection. 1 To help care for the teats of dairy cows, some dairy farmers will wash and clean the teats on a regular basis. However, excess washing and cleaning particularly with detergents and soaps, can strip the skin of the udder and teats of its natural emollients. This subsequently can lead to cracking and scarring of the skin surface, which in turn can potentially lead to bacterial infection. The cracking of the skin of the teats can also have detrimental effects on milk production. The milking action on teats having cracked skin can lead to pain-avoidance behaviours, such as retaining milk. As an alternative to the use of detergents and soaps, teats sprays may be used by dairy farmers to help maintain healthy skin on the teats of dairy cows. The spray can also assist in the repair of minor injuries to the teats as well as help prevent and/or control of mastitis and other bacterial infections that may develop in the teats and udders of dairy cows. Conventional teat sprays generally use inorganic chemicals as their active antimicrobial agent. Such chemicals include iodine or chlorhexidine. An example of one such teat spray is TeatX*, manufactured and distributed by Deosan* (www.deosan.co.nz). Iodine and chlorhexidine are relatively expensive actives, and therefore the manufacture of teat sprays can represent a significant financial investment. There is also a subsequent impact on the retail price per unit for such teat sprays. Conventional teat sprays are often provided as concentrates which have to be diluted for safe use. Using iodine at too high a level can result in burns. Furthermore, because of the expense involved, care must be taken when diluting the concentrate. However, it should not be diluted too much as the teat spray may have reduced efficacy. The use of chemicals as actives can also create toxicity and environmental issues. Many active agents used in teat sprays are not generally recognised as safe (GRAS). Furthermore, conventional teat sprays can represent a food safety or residue threat to 2 people consuming milk or dairy products derived from cows treated with conventional teat sprays. There is an increasing awareness amongst the public for the need for environmentally friendly conduct by industries and businesses. Dairy farming is no exception, and there is a growing shift way from the use of potentially harmful chemicals, such as those used in many veterinary products, which may enter the food chain in a variety of ways. Thus, in New Zealand there are increasing numbers of dairy farms that are being managed in such a way to obtain organic certification by recognised bodies such as AsureQuality (http://rww~orcaniccertitication.co.nz/). To achieve this certification the use of non-organic chemicals, such as teat sprays including iodine or chlorhexidine, is not desirable. All constituents of a formulation must be approved before organic certification of a particular product can be allowed. However, this then limits the organic dairy farmer in their choice of available products for management of the teat condition of their cows. Such products are preferably animal friendly while also being as environmentally sensitive as practical. It is an object of the present invention to address the foregoing problems or at least to provide the public with a useful choice. Further aspects and advantages of the present invention will become apparent from the ensuing description which is given by way of example only. All references, including any patents or patent applications cited in this specification are hereby incorporated by reference. No admission is made that any reference constitutes prior art. The discussion of the references states what their authors assert, and the applicants reserve the right to challenge the accuracy and pertinency of the cited documents. It will be clearly understood that, although a number of prior art publications are referred to herein, this reference does not constitute an admission that any of these documents form part of the common general knowledge in the art, in New Zealand or in any other country. 3 Throughout this specification, the word "comprise", or variations thereof such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element, integer or step, or group of elements integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps. DISCLOSURE OF THE INVENTION According to one aspect of the present invention there is provided a topical formulation, wherein the formulation includes: a diluent, and an emollient in an amount from 25% to 60% by weight, and an organic antimicrobial active in an amount from 5% to 20% by weight, characterised in that the organic antimicrobial active is sodium chloride, and wherein the emollient is glycerin, the formulation also including a herbal extract, wherein the herbal extract is aloe vera. According to another aspect of the present invention there is provided a preparation for a topical formulation, wherein the formulation includes: a diluent, and an emollient in an amount from 25% to 60% by weight, and an organic antimicrobial active in an amount from 5% to 20% by weight, characterised in that the organic antimicrobial active is sodium chloride, and wherein the emollient is glycerin, the formulation also including a herbal extract, wherein the herbal extract is aloe vera in an amount from 1 to 5% by weight. 4 According to another aspect of the present invention, there is provided a method of treating a condition of the skin of a non-human mammal with a topical formulation, wherein the formulation includes a diluent, an emollient in an amount from 25% to 60% by weight, an organic antimicrobial active in an amount from 5% to 20% by weight, wherein the organic antimicrobial active is sodium chloride, and wherein the emollient is glycerin, the formulation also including a herbal extract, wherein the herbal extract is aloe vera. the method characterised by the step of: a) applying the formulation to the skin of the non-human mammal. According to another aspect of the present invention, there is provided a method of treating a condition of the skin of a non-human mammal with a topical formulation substantially as described above, the method including the additional step prior to applying the formulation to the skin of the mammal of: b) diluting the formulation with water by a factor of between approximately 3:1 (2 parts water to 1 part formulation) and 10:1. The present invention relates to a topical formulation intended for application to the skin of a non-human mammal. The non-human mammal may be any mammal that may require treatment of the skin. For example, the mammal may be a dog, a cow or the like. Reference shall now be made throughout the remainder of the specification to the non-human mammal being a cow, although it should be appreciated that this is not meant to be limiting. Cows are valued as dairy animals, and dairying is a significant primary industry in many countries. However, it will be appreciated that goats and sheep are also valued dairy animals, and the present invention may readily be used with these animals as well. The formulation may be applied to any area of the skin which may have a condition requiring treatment. 5 The condition may be any condition in which the skin becomes damaged or dehydrated. For example, the condition may be cracking, chafing, windburn or sunburn of the skin. Other examples of conditions to be treated with the present invention may be conditions in which pathogens such as bacteria, fungi or viruses play a role, either causing skin damage or dehydration of the skin or causing more serious conditions of damaged or dehydrated areas of the skin, such as infection. Examples of such conditions include acne, athlete's foot, psoriasis or dermatitis. All these conditions, as well as damaged and/or dehydrated skin can compromise the natural barrier function of the skin. It should be noted, the stated examples of skin conditions are not meant to be limiting and persons skilled in the art will readily appreciate a variety of skin conditions may be treated with the present invention. The formulation is to be applied to the area of skin requiring treatment or preventative maintenance. For example, the formulation may be applied to the ears, nose or in skin folds. In preferred embodiments of the present invention, the formulation is applied to the teats of a cow, and reference shall now be made to the use of the present invention on the teats of a cow. The teats of a cow can become damaged as a result of machine milking or through contact with the ground or objects in the path of the teats as the cow moves. Another source of trauma to the teats can be excessive moisture, which can lead to the skin of the teats becoming cracked. Such cracks then become points of entry for pathogens. The present invention is ideal for use to treat or prevent damage to the skin of the teat. The formulation may be applied to the skin in a number of ways, for example as a paste, gel or ointment. In preferred embodiments of the present invention, the formulation is applied to the teats as a spray. Reference shall now be made throughout the remainder of the specification 6 to the formulation being used as a teat spray. An important aspect of the present invention is that the constituents of the formulation are organic and Generally Recognised As Safe (GRAS). The use of the term "organic" in the context of the present invention should be understood to mean that the formulation of the present invention does not include synthetic compounds. GRAS is an acronym used by the United States Food and Drug Administration (FDA) to refer to any substance that is approved by the FDA for intentional addition to food as a food additive, unless the substance is generally recognised, by qualified experts, as having already been sufficiently proven to be safe for its intended use. The formulation may be provided as a concentrate which needs to be diluted with water before application. Such an approach may be preferred by bulk users such as larger scale dairy farms. Alternatively, the formulation may be provided to the consumer as a working solution, ready for immediate use with no dilution step. Small scale users, such as lifestylers, may prefer such products for being easy to use. The constituents of the formulation are now discussed, and unless otherwise indicated are expressed as a percentage of a concentrate which would need to be diluted by a factor of approximately 2 parts to 9 parts water to 1 part concentrate. The formulation includes a diluent or thinner. A diluent should be understood to mean a diluting agent, and reduces the viscosity of the remaining constituents of the formulation. The diluent may be any suitable substance which is chemically inert, and persons skilled in the art will readily recognise which liquids or substances would be suitable for use as a diluent, depending on whether the formulation is to be applied to the cow as an ointment, paste, gel or spray. 7 For example, when the formulation is being applied to the animal as a spray, the diluent may be water (formula H 2 0). In preferred embodiments of the present invention, the diluent is deionised water. Deionised water is water from which any mineral ions have been removed. This ensures the water is as pure as possible. The amount of deionised water present in the formulation will depend on the amount of emollient and microbial organic active that is also present, but in preferred embodiments of the present invention, the formulation contains from 30 to 60% by weight of deionised water. In preferred embodiments of the present invention, the formulation contains from 30 to 40% by weight of deionised water, this being the appropriate amount of diluent required for full dissolution of the organic antimicrobial active. The formulation includes an emollient. An emollient should be understood to be a moisturiser which acts to reduce evaporation of water in the skin, thereby increasing the skin's hydration. The emollient also has bacteriostatic or antimicrobial properties. The emollient should be understood to be glycerin (also known as glycerine or glycerol) and reference shall now be made throughout the remainder of this specification to the emollient being glycerin. The inventors use glycerin in the present formulation for a number of reasons. Firstly, the use of glycerin (formula C 3

H

8 0 3 ) as an emollient is well known and it plays an important part in the maintenance of a healthy skin barrier. It is a common constituent of existing conventional teat sprays for this reason. The teats of a cow are subject to constant exposure to moisture, particularly in the winter months and this can lead to moisture associated skin damage. This impacts on the skin's natural defence mechanisms and can compromise the barrier function. The use of glycerin counteracts this and ensures good hydration of the skin barrier. 8 Glycerin is also known for its bacteriostatic properties. Bacteriostatic should be understood to mean an agent that stops or inhibits bacteria from reproducing as opposed to killing them, as is the case with a bactericide. Glycerin may be cheaply and easily sourced, making it an ideal and cost efficient emollient for the purpose of the present invention. Furthermore, as it is GRAS, glycerin is commonly used in foods. This will facilitate organic certification of the present invention. A factor that affects the amount of glycerin that may be present in the formulation is its limited ability to dilute the organic active. There must be a certain amount of diluent present in the formulation as well in order to achieve the full dissolution of the organic antimicrobial active. The formulation of the present invention should be understood to contain from 25 to 60% by weight of glycerin. In a particularly preferred embodiment, the formulation contains from 45% to 55% by weight of glycerin. In an even more preferred embodiment, the formulation contains from 48% to 52% by weight of glycerin. This is a significantly higher amount of glycerin compared to other conventional teat sprays which may contain glycerin in addition to inorganic actives. This means that the hydration effect of the glycerin is particularly pronounced. It also means that the bacteriostatic action of the glycerin is maximised. The formulation also includes an antimicrobial organic agent. This should be understood to mean that the organic agent has properties that inhibit, kill or otherwise detrimentally affects bacteria, fungi, viruses and/or other pathogens. In the present invention, the antimicrobial organic agent is sodium chloride. 9 Sodium chloride (formula NaCI), which throughout the remainder of this specification shall be referred to as salt, although in some embodiments of the present invention, iodised salt may be used, is known to have antibacterial properties. It is a natural desiccant which may disrupt the metabolic processes of many pathogens. Salt, as a desiccant, is not used as an active agent in existing teat sprays. Conventional thinking directs the skilled addressee away from constituents that may adversely affect the skin by drying it out. However, in their search for an organic teat spray, The inventors have found that combination of salt and an appropriate amount of glycerin works surprisingly well in improving the teat condition of cows treated with the teat spray. The glycerin acts to counter the desiccant property of salt, ensuring the skin remains as hydrated as possible. The presence of the salt can help reduce swelling and oedema of the skin of the teats. This, together with the restoration of the skin barrier function due to the glycerin, helps with restoration of damaged skin more quickly than with conventional teat sprays. The salt constituent of the formulation is its key active, and is particularly advantageous for a number of reasons. These include: * readily available; * low cost; * readily soluble in water; * is approved in some countries for inclusion in organic formulations; * does not react with other ingredients. The antimicrobial property of salt also supplements the bacteriostatic action of the glycerin component of the formulation. Additionally, the combined bacteriostatic nature of glycerin and the antimicrobial effect of salt increases the efficacy of the formulation. 10 Furthermore, as it is GRAS, salt is commonly used as a food preservative. This will facilitate organic certification of the present invention. Salt is also hypertonic, and may act to reduce swelling and oedema in damaged teats or teats affected by swelling associated with mastitis infections by drawing water away from the swollen or damaged area. However, salt, as noted above, is also a desiccant. Thus the amount of salt present in the formulation needs to be an appropriate amount to avoid excessive dehydration for which the emollient present is insufficient, while still allowing a small degree of water loss to assist in reducing swelling associated with trauma and infections. The formulation of the present invention should be understood to contain from 5 to 20% by weight of sodium chloride. In a particularly preferred embodiment, the formulation contains from 12 to 13% by weight of sodium chloride. The formulation of the present invention also contains a herbal extract which, when used on skin, has therapeutic properties. In the present invention, it should be understood that the herbal extract is aloe vera. Aloe vera is well known for its soothing and restorative properties when used on the skin. It can accelerate healing of damaged skin and is also known to have bactericidal and fungicidal properties. In preferred embodiments of the present invention, the formation includes from 1 to 5% by weight of aloe vera powder. The inventors have found that the combination of glycerin, salt and aloe vera provides unexpectedly good results in improvement of skin condition such that incidence rates of mastitis in dairy herds treated with the invention are reduced compared to previous seasons where conventional teat sprays have been used. 11 In some embodiments of the present invention, the formulation may include additional constituents. For example, when used as a teat spray, the formulation may include a dye. This is useful when applying the teat spray as may indicate to the user the extent of the coverage of the teat spray when applying it to the skin of the udder and teats. The dye may be any suitable dye which is GRAS. The inventors prefer Indigo Carmine supra food grade dye (CAS Number 860-22-0) and/or Erythrosine supra food grade dye (CAS Number 16423-68-0). Both dyes have been approved by the FDA and the Food Safety Agency of the United Kingdom (FSA). These dyes result in the formulation having a visibly detectable reddish colouring. However, the disclosed examples are not meant to be limiting and persons skilled in the art will appreciate that dyes for any colour may be used with the present invention so long as they are recognised as being GRAS. In preferred embodiments of the present invention, the formation includes from 0.1 to 2% by weight of dye. Other optional constituents may include additional emollients and/or actives, so long as such constituents are organic. In a particularly preferred embodiment, the formulation, in its concentrate form, includes the constituents as expressed in table 1: Ingredient name (common or chemical) CAS Number Quantity Function (g/L) Deionised water 7732-18-5 372.3 Diluent Glycerine BP 56-81-5 504 Emollient Sodium Chloride Solar Salt (Grade 27) 7647-14-5 122.5 Organic antimicrobial active Erythrosine supra Food grade dye 16423-68-0 0.1 Food grade Dye 12 Indigo carmine supra food grade dye 860-22-0 0.1 Food grade Dye Aloe Vera powder 200:1 100084-89-7 3 Herbal extract Table 1: Constituents of the concentrate (prior to dilution to a working solution) formulation (as g/L) with an indication of the function of each constituent. An example of a method of preparing the formulation shall now be described. To a main tank of 100 litres, 32.03 kilograms of deionised water is added. The tank is then heated to 45 to 500 Celsius. While being heated, sodium chloride, 12.25 kilograms is added to the main tank, together with 0.3 kilograms of aloe vera powder (200:1). The contents of the main tank is mixed with a Silverson* mixer for 15 minutes until the solution is clear and the powders are dissolved. Once the solution is clear, 50.4 kilograms of Glycerine BP is added, and mixed into the solution. A separate formulation is prepared for the dye. To a 10 litre tank containing 5 kilograms of deionised water, 0.01 kilograms of Erythosine Supra FG dye is added together with 0.01 kilograms of Indigo Carmine Supra FG dye. The mixture is mixed to ensure even dispersion, and is then added to the main tank. The resulting solution is mixed for a further 10 minutes, with deionised water (0.3 kilograms) being added to bring the formulation up to 100 litres. The formulation may then diluted by a factor of approximately 3 to 10 into a diluent (water) for a working solution. The inventors prefer a dilution factor of approximately 5:1 (four parts water to one part concentrate). This dilution factor is consistent with conventional teat sprays making it easier for the present invention to gain market acceptance. 13 However, this is not meant to be limiting, and good results have been achieved with the preferred concentrate formulation being diluted by a factor of approximately 7:1. Higher dilution factors, such as 7:1 or even 10:1, may be used if the herd is milked twice daily as this represents an opportunity for the present invention to be applied twice a day. This may justify the use of higher dilution factors, as the twice-daily application may offset the reduced efficacy of the higher dilution. This may also allow prolonged use of the concentrate. The present invention offers a number of advantages, including: * a teat spray which may be produced in a cost effective manner; * a teat spray in which all its constituents are GRAS; * a teat spray in which all its constituents are organic, such that the teat spray may be organically certified; * a teat spray that has an efficacy comparable or superior to conventional teat sprays; * at the very least, the present invention offers the public a useful choice. BEST MODES FOR CARRYING OUT THE INVENTION The following experimentation is given by way of example, and is not meant to be limiting. Objective The objective of the inventors was to develop an organic teat spray suitable for use on dairy cows. The various formulations were trialed on a farm in the Northland region of 14 New Zealand. The dairy herd was milked once daily, and thus there were approximately 24 hours between each milking event. Climatically, the season during which the formulations were trialed was consistent with the previous season, in which conventional teat sprays were used. Experiment Formulation 1 A first formulation (Fl) was developed in which the working solution (dilution factor 7 parts water to 1 part concentrate) (the list of constituents of F1 tabulated below in table 2) included salt at approximately 59.16 g/kg and glycerin at approximately 27.38 g/kg, the balance of the formulation made up of a diluent in the form of distilled water. The amount of glycerin in F1 is comparable to many existing conventional teat sprays. Dyes were added to provide an indication of coverage, these being Country Mile Red Marker dye (Rhodamine) and FIL Done That dye (Indigo Carmine) but only in trace amounts. Ingredient name (common or chemical) Quantity Function (g/L) Deionised water 394 Diluent Glycerine BP 191 Emollient Sodium Chloride Solar Salt 414 Organic antimicrobial active Erythrosine supra Food grade dye 0.004 Food grade Dye Indigo carmine supra food grade dye 0.004 Food grade I Dye Table 2: Constituents of the concentrate (prior to dilution) of F1 (as g/L) with an indication of the function of each constituent. Results The working solution was applied to the teats using a conventional hand held spray gun, following the removal of the teat cups after each milking event. 15 After several days of use, it was observed that F1 appeared to result in excessive drying of the teat. It was speculated that there was insufficient glycerin in the formulation to counter the hypertonicity of the salt. Formulation 2 A second formulation (F2) was prepared in which the salt content in the working solution was decreased to approximately 53.36 g/kg and glycerin increased to approximately 41.41 g/kg. As with F1, the working solution had been diluted from the concentrate by a factor of 7:1. The dyes used were also increased but only in marginal amounts. This was to improve the visibility of the residual colour of the F2 on the teats following application as a spray. Results The trial with F2 (and the third formulation) took place during the wettest part of the season, when ground condition is at its poorest. Historically, this is when cracking of the skin of the teats is at its worst. It was observed that after ten days of trial with F2 that the teat condition improved somewhat. The skin of the teat felt softer to the touch, and cracking was reduced from what would have otherwise been expected for the time of the season. However, the visibility of F2 following application to the teats remained inconsistent. Visibility is an important factor when using teat sprays as it is preferable to be as efficient as possible with coverage of the spray. Formulation 3 A third formulation (F3) was then trialed. The glycerin content was increased substantially to 92.80 g/kg while the salt content remained unchanged at approximately 53.36 g/kg. In an attempt to provide a more visible spray, the amount of dye used was 16 increased, from 0.00008 g/kg in the second formulation, to 0.001 g/kg for each of the two dyes used in the third formulation. As with the previous formulations, the working solution had been diluted by a factor of 7:1. Results Superior results were observed using F3 than seen when using F2. Teat condition improved considerably and the cracking was significantly reduced. It was later found that the manufacturer specifications for the salt were incorrect, and the specific density was double from what was expected. Thus, F3, as well as the previous formulations trialed, had a salt concentration twice what was intended. Formulation 4 As a result of the issue with the salt concentration issue identified following the trial of formulation 3, the new formulation (F4) was revised such that the working solution included salt at approximately 28.42 g/kg, with glycerin being increased to approximately 117.2 g/kg. The concentration of each of the two dyes was increased to 0.00145 g/kg, with the balance of 854 g/kg being diluent in the form of distilled water. Results The teats of treated cows showed a noticeable improvement, which was believed to be as a result of the increase in glycerin. It was particularly noticeable that cows that had ongoing problems with cracked teats began to show improved condition. At the same time, somatic cell count (SCC) was generally reduced when compared to animals being treated with conventional teat sprays in previous seasons. Furthermore, subclinical mastitis in the treated herd was reduced, as measured by SCC, was reduced by about 20% compared to the previous season, as tabulated in Table 3 below. This SCC data is based on regular tests carried out on the milk collected from the trial farm. When the tests are performed on the same day each year, it allows yearly 17 comparisons of SCC in the herd. In some instances, comparisons are not possible due to the test not being performed on the particular day in question. Date Previous season Trial season Current season 2/8 317 254 No data 12/8 284 225 No data 21/8 217 176 245 1/9 210 190 207 11/9 244 173 182 21/9 261 206 185 1/10 237 188 203 11/10 223 187 180 21/10 305 No data 178 1/11 267 232 162 11/11 294 212 181 21/11 306 213 205 1/12 297 249 225 Table 3: SCC (x 1000) of across a four-month period of the previous season (using conventional teat sprays) compared to the trial season in which formulations 1 to 4 were tested and the current season in which the preferred embodiment of the formulation was trialed. The average number of cows infected with mastitis at any one time during the season of trials was 2.75. This is a significant drop of approximately 60% from the previous season, during which average number of infected cows was 4.91. 18 It should be appreciated that having mastitis affected cows is detrimental to milk production as treatment requires antibiotics. The milk of the affected animal has to be withheld until antibiotic residues decline to acceptable levels. Thus reducing mastitis incidence rates such, that on average, the milk production of two cows across an entire season is not lost, is of economic value to the farmer. In later trials carried out throughout the current season, aloe vera, a certified organic herbal extract, was added to the formulation in an amount of approximately 0.696 g/kg. Consequently, further improvement in the condition of the skin of the teats was observed. No other variations of the formulation were trialed. Incidence rates of mastitis also continued to decline with the addition of aloe vera to the formulation. The average number of cows affected with mastitis fell from 2.75 to 2.42 during the following milking season. Referring back to Table 3, it will be seen that following an initial high SCC result for 2 August in the current season, the presence of SCC declined to an amount that was consistently less than that observed during the trial season. This demonstrates the efficacy of the preferred formulation. Prior to the commencement of the later trials, it was found that the Rhodamine based dye as used to date was not GRAS. As a result, the dyes were replaced with food grade dyes, these being Indigo Carmine and Erythosine. Both were included in concentrations of approximately 0.023 g/kg. Additionally, it was decided to lower the dilution factor from 7:1 to 5:1 to make the dilution factor consistent with conventional sprays. It was thought that this may assist in the product gaining consumer acceptance once it enters the market. The significant reduction in the incidence rates of clinical and sub-clinical mastitis that was observed in the trials was a surprising and unexpected result of using the present formulation. It is believed that this is a result of a synergistic effect of the salt, glycerin 19 and aloe vera all having bacteriostatic and bactericidal properties in conjunction with the superior teat skin condition that can be obtained with the present formulation. In the season prior to the trials, cows were milked twice daily, and were sprayed with conventional sprays at each milking event. Therefore, a single application of the present formulation not only resulted in better teat condition as well as reduced incidences of mastitis, but with less labour input and usage of product. This has significant implications for dairy farming as an opportunity to save costs, time and labour. Therefore it is likely that, when the present invention is used on farms being milked twice daily, superior results to those documented here may been seen on farms being milked twice daily, assuming the dilution factor remained consistent with what had been trialed. It is possible that the concentrate could be diluted further on farms operating herds milked twice a day; the reduced efficacy of a single application could be compensated for by being applied twice, after each milking event. Further variations of the formulation were trialed in the following season to ensure the results observed the previous season were not due to other factors. Conclusion When salt is used in a therapeutically effective amount in conjunction with aloe vera and an appropriate amount of glycerin, positive changes in the skin of the teats of the treated animals was observed. The hypertonicity of the salt reduces the swelling and oedema of damaged teats while the glycerin fulfills its emollient function, restoring skin barrier function and counteracting the desiccant effect of the salt. The combined bactericidal effects of the salt and aloe vera constituents of the formulation are detrimental to any external pathogens which may be present on the skin of the teats. As a consequence, incidences of bacterial infections, i.e. mastitis, were reduced with a subsequent positive effect on milk production of the treated herd when compared to 20 herds treated with conventional products. As the skin condition of the teats was superior when treated with the present formulation compared to treatment with conventional teat sprays, there was less opportunity for pathogens to enter the teats and potentially develop mastitis. All the constituents of the formulation are GRAS and this lends the formulation for use on "organic" dairy farms for which hitherto, conventional teat sprays were not suitable. Aspects of the present invention have been described by way of example only and it should be appreciated that modifications and additions may be made thereto without departing from the scope thereof as defined in the appended claims. 21

Claims (5)

1. A topical formulation, wherein the formulation contains: a diluent, and an emollient in an amount from 25% to 60% by weight, and an organic antimicrobial active in an amount from 5% to 20% by weight, characterised in that the organic antimicrobial active is sodium chloride, and wherein the emollient is glycerin, the formulation also including a herbal extract, wherein the herbal extract is aloe vera in an amount from 1 to 5% by weight.

2. The topical formulation of claim 1 wherein the formulation includes at least one dye, wherein the dye is indigo carmine supra food grade dye or erythrosine supra food grade dye.

3. The topical formulation of either claim 1 or claim 2 wherein the formulation is diluted with water by a factor of between approximately 3:1 (2 parts water to 1 part formulation) and 10:1 (9 parts water to 1 part formulation).

4. The topical formulation of any one of claims 1 to 3 wherein the diluent of the formulation is water.

5. The topical formulation of any one of claims 1 to 3 wherein the formulation is in one of the following forms: a sprayable liquid, an ointment, paste or gel. 22