AU775935B2 - Antimicrobial compositions and method of treatment of poultry - Google Patents

Description

AUSTRALIA

Patents Act COMPLETE SPECIFICATION

(ORIGINAL)

Class Int. Class Application Number: Lodged: Complete Specification Lodged: Accepted: Published: Priority 9 Related Art: Name of Applicant: Chemeq Ltd Actual Inventor(s): Graham John Hamilton Melrose Address for Service: PHILLIPS ORMONDE FITZPATRICK Patent and Trade Mark Attorneys 367 Collins Street Melbourne 3000 AUSTRALIA Invention Title: ANTIMICROBIAL COMPOSITIONS AND METHOD OF TREATMENT OF POULTRY Our Ref 661683 POF Code: 454354/454354 The following statement is a full description of this invention, including the best method of performing it known to applicant(s): -1- 4 W 2 ANTIMICROBIAL COMPOSITIONS AND METHOD OF TREATMENT OF

POULTRY

FIELD OF THE INVENTION The present invention relates to antimicrobial polymeric compositions and their use to improve growth rate and in treatment or prophylaxis of gastrointestinal disease in poultry.

BACKGROUND ART Antibacterial growth promoting agents have been used in the poultry industry for many years. Penicillin and related antibiotics provide a significant increase in :i 15 growth rate and also guard against serious poultry diseases such as necrotic enteritis and coccidiosis which can have a devastating effect on commercial poultry production.

The use of conventional antibiotics as growth promotants is believed to have contributed to the development of antibacterial resistance in pathogenic bacteria. As a result there is a demand for a significant reduction in the use of pharmamedical antibiotics in the poultry. Indeed the use of pharmamedical antibiotic as growth promotants and prophylactic treatment in poultry has been banned in some countries. The cessation of antibiotic use in prophylactic treatment of poultry has however resulted in a significant increase in the incidence of serious poultry diseases such as necrotic enteritis and a reduction in growth rates.

There is a need for an antimicrobial growth promotant and a method of treatment or prophylaxis of poultry diseases which reduces these problems.

Wlje 13P WpAneq Au Appi dos 3 SUMMARY OF THE INVENTION In accordance with a first aspect the invention provides a method of promoting weight gain or treating or preventing gastrointestinal disease in poultry comprising adding to the drinking water of the poultry an antimicrobial composition comprising an acrolein polymer having repeating units of formula I:

H

C

CH2"

(I)

O H or this unit in its hydrated, hemi-acetal or acetal form and in an amount of from 0.0001% to 70% by weight based on the total weight of the antimicrobial composition and a carrier therefor selected from the group consisting of a 10 controlled release entity, water, an alkanol, polyhydric alcohols (including diols) and mixtures thereof.

Examples of the hydrated, acetal or hemiacetal forms may be represented by the formulae:

CH

2 ^C (a)

CH

/C\

S.RO

OR

CH

2 .H CH-C H J (b) CH2

CH

2 CHz CH CH 30 nOR RO 0 n O aiW"S"SSSJBPpmdo

CH

2 R (d)

RO\

CH

CH

CH

CH=CH

2 (e) o/

CH

2 (f)

CH

2

CH/

wherein R is hydrogen and n is an integer of one or more.

The antimicrobial composition is administered as part of the drinking water of the poultry and preferably provides a daily dose of the acrolein polymer in the range of from 0.01 to 500 mg of said polymer per kilogram of animal bodyweight per day. More preferably the amount administered is in the range of from 0.05 25 to 50mg/Kg/day and most preferably from 0.1 to 40 mg/Kg/day.

Preferably the antimicrobial is mixed with drinking water in an amount of from 0.0001% to 10% by weight of antimicrobial polymer and preferably from 0.01% to 2% by weight of antimicrobial polymer.

In a further aspect the invention provides an antimicrobial growth promoting composition for use as a concentrate for addition to drinking water comprising poly(2-propenal, 2-propenoic acid) and a carrier therefor comprising a polyhydric alcohol.

DETAILED DESCRIPTION OF THE INVENTION The antimicrobial of the invention is preferably a poly( 2 -propenal, 2-propenoic acid) polymer. The poly(2-propenal, 2-propenoic acid) polymers are preferably prepared by polymerisation of acrolein (preferably in aqueous reaction media) by anionic polymerisation, followed by autoxidation. The polymers contain the repeating unit of formula I and at least one (and typically a mixture) of the hydrated, hemiacetal and acetal forms.

The hydrated, hemiacetal and acetal forms formed by polymerisation of acrolein are known to arise from the various carbon-carbon and carbon-oxygen polymerisation mechanisms of acrolein. For example the hydrated form is typically the hydrated diol form, the hemiacetal or acetal form may be formed from the condensation of the diol form with the aldehyde or diol form, the tetrahydropyran or fused tetrahydropyran form may be formed from condensation of the diol form and the aldol-Michael self condensation form.

Typical examples of these forms are shown in formula to below:

H

I

C

C

o gig* 6 C CH 2 IH (a) RO RO IH (b) RO 0

,OH

2 OH 2 OH2 II i(C) UH OH O H 0 0\n OR OH2 (d)

RO

OH

OH

2 OH=0H 2 I (e) CH 0 flfl.%Spe eWMeMMe Au Ap*AMdc /o\

CH

2 (f)

CH

2

CH

wherein R is hydrogen and n is an integer of one or more. The proportion of repeating unit of formula I is typically less than 20% and frequently from 5 to The poly(2-propenal, 2-propenoic acid) will generally contain no more than on a molar basis of monomer units from monomers other than acrolein and is most preferably an acrolein homopolymer (before autoxidation). Where used S* 10 other monomers may be selected from the group consisting of acrylic acid and vinyl pyrolidone. The 2-propenoic acid groups are typically present in an amount of from 0.1 to 5 moles of carboxyl groups per kilogram. The poly(2-propenal, 2propenoic acid) polymers typically have a number average molecular weight of over 1000 and most preferably over 2000. Typically the molecular weight is 15 less than 10,000.

The antimicrobial composition may include a polyol carrier. The preferred polyols are alkylene glycols such as ethylene, propylene and butylene .glycols and most preferably polyalkylene glycols such as polyethylene glycol, propylene glycol and copolymers and mixtures of such polyols. The most preferred polyols •are polyalkylene glycols (particularly polyethylene glycols) of molecular weight in the range of from 200 to 2000 and more preferably 200 to1000.

The amount of polyol in the composition of the invention is typically in the range of from 2 to 95% of the composition before mixing with water or feed. The weight ratio of polyol to antimicrobial polymer is preferably in the range of from 50:1 to 1:1.

The antimicrobial of the invention may be formulated for oral or rectal administration but oral administration in the feed or water is preferred.

WW*tspe SmcheMq A. ApvW.d a W 8 The antimicrobial of the invention is particularly useful in treatment and prophylaxis of diarrhoea, dysentery and gastroenteritis. The antimicrobial of the invention may also be used to improve the rate of weight gain in farm animals.

We have found that the antimicrobial of the invention may be used as a growth promotant in place of the presently used antibiotics. Drug resistance in pathogenic bacteria is a problem of major clinical importance in human medicine. This problem is exacerbated by the use of important antibiotics in animal feed to provide weight gain in farm animals particularly poultry and pigs.

Indeed, in some European countries the use of conventional antibiotics in animal feeds has been banned. The antimicrobial of the invention may be used in treatment of animals to significantly extend the useful life of conventional antibiotics in human treatment.

15 We have found the antimicrobial of the invention to be effective against a wide *range of microbes including protozoa, Gram positive bacteria and Gram negative bacteria. Of the Gram negative bacteria the antimicrobial of the invention has been found to provide broad spectrum activity against coliforms or Enterobacteria. It is particularly useful in treatment of gastrointestinal diseases resulting from E. coli infection from E. coli such as enterotoxigenic E. coli and phaemolytic E. coli. Colibacillosis is a significant problem in the pig industry.

The disease is generally associated with proliferation of p-haemolytic E. coli. in the small intestine and result in significantly reduced weight gains.

The action of the antimicrobial of the invention is non-specific so that it may be used in control of a wide range of microbes including for example coliforms, salmonella, campylobacter, P aeruginosa, Helicobacter, Proteus, Enterobacteria, Yeasts, Protozoa, Clostridia and Shigella.

Coccidiosis is a protozoal disease which if left uncontrolled has a devastating effect on poultry We have found that the antimicrobial of the invention may be used in the treatment or prevention of coccidiosis in poultry. In chickens typical clinical signs of coccidiosis include lack of thriving, rapid loss of weight, diarrhoea and dysentery. The most serious effects take place in the intestine W.aenniespeaes'hemeq A. Appin doc

E

9 where the protozoa tend to invade the mucosa and cause epithelial damage, lesions and haemorrhage. Vaccines have been used in an attempt to prevent coccidiosis but have side effects including the tendency to reduce weight and feed efficiency.

The antimicrobial of the invention may be used in combination with other drugs known to have activity against coccidiosis. Such drugs include nitro-carbanilide, quinoline, pyridon, guanidine, quinoxaline, toltrazural, toluamide, potentiated sulfa drugs and ionophore with carbanilide.

Clostridia are Gram positive bacteria responsible for serious disease in a range 0: of animals. For example, necrotic enteritis is a disease known to affect commercial poultry. Clostridia bacterial produce exotoxins which are some of the most toxic of all known toxins. Necrotic enteritis particularly effects broilers 15 of between 14 and 42 days of age. The condition causes pronounced apathy, diarrhoea and can cause death within hours.

When the antimicrobial polymer of the invention is incorporated into an animal feed or water this may be done in the usual manner. In a preferred embodiment the antimicrobial of the invention is incorporated in a premix. The premix will preferably include the antimicrobial, a physiologically acceptable carrier and optionally a feedstuff.

The premix is generally in a relatively concentrated form and is adapted to be diluted with other material such as one or more of the other carriers, vitamins and mineral supplements and feedstuff to form the final animal feed. The premix preferably includes the antimicrobial in a concentration in the range of from 0.1 to 70% by weight, preferably 0.5 to 50% by weight. The optimum concentration will depend on whether the treatment is preventative, for control or remedial and whether the antimicrobial of the invention is the only active or whether it is used in concomitant therapy with other materials or antimicrobials.

The feed component will preferably be a wheat protein, soy protein or other suitable grain or legume.

W*Anr~ea*s WWeQ Au App dc In one embodiment the concentrated composition of the antimicrobial is in a controlled-release form. The controlled release form will include the antimicrobial and a polymeric material for providing controlled release of the antimicrobial from the controlled-release systems and is particularly useful in compositions for addition to solid feed material. As a result of the controlled release formulation the release of the antimicrobial may be delayed so as to occur mainly in the duodenum. A controlled release polymer may also minimise rejection of the composition due to taste or be used for rectal suppositories.

It is preferred that the method involve addition of the composition to the drinking water used by poultry.

o..

An antimicrobial composition in accordance with the invention may be alternatively though less preferably in the form of pellets, pills or like solid 15 composition. The pellets containing the antimicrobial of the invention may be prepared by the steps of: dissolving said antimicrobial in an aqueous alkaline or basic solution; (ii) neutralising said solution with acid; (iii) adding to said neutralised solution insoluble, cross-linked, "'"absorbent polymers of acrylic acid and/or copolymers of acrylamide and acrylic acid, to form wet swollen pellets; and (iv) optionally, wholly or partially drying said wet swollen pellets.

The so-formed wet, swollen pellets may be used either wet, partially dried or wholly dried, as an additive to, for example, animal feed. This system is further designed so that the carboxyl-containing groups of the outer polymeric matrix cause the Subject Polymers to remain essentially contained within the matrix when in the acidic environment of the stomach. In the alkaline environment of the duodenum, the carboxyl groups of the matrix become ionised and mutuallyrepelling, and the pellet rapidly swells to allow the Subject Polymers, aided by repulsion among their own ionic groups, to be excluded by a diffusion process, approximately matching the speed of passage of feed through the duodenum.

W.V ssoedesclmeq Au Ap W.oc 11 In this invention, the term, "controlled release system" is used in the same context as that in, and includes the same range of examples as quoted in "Controlled Drug Delivery" (Robinson Lee, 1987). Many other pH-sensitive controlled-release systems which are known in the art (Robinson and Lee, 1987) may be substituted for the polymer of acrylic acid or copolymer of acrylamide and acrylic acid. For example, soluble and anionic, or insoluble cross-linked and anionic, cellulosic systems; or soluble and anionic, or insoluble cross-linked and anionic polymers derived from any generic acrylic acid polymer and/or its derivatives. Such cross-linked and insoluble polymers are preferred since they swell and also are less likely to be metabolised.

It is preferred that the controlled release system comprises a pH-sensitive, S: cross-linked, water-absorbent pellet, which when wet is a gel.

The invention also provides an animal feed composition comprising the antimicrobial of the invention and a feedstuff. The antimicrobial is preferably present in an amount of from 0.001 to 70% of the total feed composition more preferably 0.001 to 25% and most preferably from 0.01 to 5% of the total feed composition.

1 In another preferred embodiment, the antimicrobial of the invention may be formulated for addition to the drinking water of animals.

The antimicrobial of the invention is preferably administered in amounts of from 0.01 to 500 mg/acrolein polymer/kg of bodyweight/day more preferably from 0.05 to 50 mg/kg/day and most preferably 0.1 to 40 mg/kg/day.

Examples of suitable additional carriers for use in compositions for administration of the antimicrobial of the invention include water, olive oil, peanut oil, sesame oil, sunflower oil, safflower oil, arachis oil, coconut oil, liquid paraffin, ethylene glycol, propylene glycol, polyethylene glycol, fatty alcohols, triglycerides, polyvinyl alcohol, partially hydrolysed polyvinyl acetate and mixtures thereof.

W.*eanncWpdes hem Au Ap0k doc 12 Solid forms for oral or rectal administration may contain pharmaceutically or veterinarally acceptable binders, sweeteners, disintegrating agents, diluents, flavourings, coating agents, preservatives, lubricants and/or time delay agents.

Suitable binders include gum acacia, gelatine, corn starch, gum tragacanth, sodium alginate, carboxymethylcellulose or polyethylene glycol. Suitable sweeteners include sucrose, lactose, glucose or flavanone glycosides such as neohesperidine dihydrochalcone. Suitable disintegrating agents include corn starch, methylcellulose, polyvinylpyrrolidone, xanthan gum, bentonite, alginic acid or agar. Suitable diluents include lactose, sorbitol, mannitol, dextrose, kaolin, cellulose, calcium carbonate, calcium silicate or dicalcium phosphate.

Suitable flavouring agents include peppermint oil, oil of wintergreen, cherry, orange or raspberry flavourings. Suitable coating agents include polymers or copolymers of acrylic acid and/or methacrylic acid and/or their esters, and/or their amides, waxes, fatty alcohols, zein, shellac or gluten. Suitable 15 preservatives include sodium benzoate, vitamin E, a-tocopherol, ascorbic acid, methyl parabens, propyl parabens or sodium bisulphite. Suitable lubricants include magnesium stearate, stearic acid, sodium oleate, sodium chloride or talc. Suitable time delay agents include glyceryl monostearate or glyceryl distearate.

Suspensions for oral or rectal administration may further comprise dispersing agents and/or suspending agents. Suitable suspending agents include sodium carboxylmethylcellulose, methylcellulose, hydroxypropylmethylcellulose, polyvinyl-pyrrolidone, sodium alginate or cetyl alcohol. Suitable dispersing agents include lecithin, polyoxyethylene esters or fatty acids such as stearic acid, polyoxyethylene sorbitol mono- or di-oleate, -stearate or -laurate, polyoxyethylene sorbitan mono- or di-oleate, -stearate or -laurate and the like.

The composition of the antimicrobial may further comprise one or more emulsifying agents. Suitable emulsifying agents include dispersing agents as exemplified above or natural gums such as gum acacia or gum tragacanth.

Compositions for administration in the method of the invention may be prepared by means known in the art for the preparation of compositions (such as in the W'~:en.*epsmde~,eq AU AP hd=C 13 art of veterinary and pharmaceutical compositions) including blending, grinding, homogenising, suspending, dissolving, emulsifying, dispersing and where appropriate, mixing of the Subject Polymers together with selected excipients, diluents, carriers and adjuvants.

For oral administration, the pharmaceutical or veterinary composition may be in the form of tablets, lozenges, pills, troches, capsules, elixirs, powders, including lyophilised powders, solutions, granules, suspensions, emulsions, syrups and tinctures. Slow-release, or delayed-release, forms may also be prepared, for example in the form of coated particles, multi-layer tablets or microgranules.

It is generally preferred that poly(2-propenal, 2-propenoic acid) is prepared from poly(2-propenal) by oxidation of the solid in air. The poly(2-propenal) polymer may be initially heated, predominantly in the dry state, to between 80 and 15 1100C. More preferably, the polymer is initially heated to about 85 0

C.

We believe that any other active agents may be adsorbed by the polymeric antimicrobial of the invention. The adsorption and its effect may be examined by examining membrane penetration of the further active alone and in combination with the polymeric antimicrobial across a membrane in contact with solvent.

In a further aspect the invention provides an antimicrobial composition comprising an antimicrobial polymer according to the invention and a further antimicrobial or chemotherapeutic adsorbed thereon.

The antimicrobial of the invention may be used in combination with other antimicrobial substances such as those selected from the classes of EDTA, lower alkanols, phenols, isothiazolinones, glutaraldehyde, alkyl parabens and mixtures thereof. When used further antimicrobials are preferably selected from glutaraldehyde, EDTA, alkyl parabens (particularly methyl parabens) sothiazolinones and phenols.

eWnnc\spedeschemesc A Appu r do 14 Compositions containing phenolic antimicrobials or glutaraldehyde generally have an unpleasant odour. Fragrances and perfumes have been used to mask the odour but are not particularly effective, particularly for phenols. We have found that the antimicrobial of the invention significantly reduces the odour problem associated with the use of these compounds.

Examples of suitable phenolic compounds include halo phenols, preferably ortho- or para-substituted halo phenols such as o-chlorophenol; alkylhalo phenols such as chloroxyphenol (p-chloro-m-xylenol); alkyl phenols such as tamylphenol; aryl phenols such as o-phenyl phenol, and benzyl-substituted halophenols such as o-chloro-p-benzylphenol. Preferably, the phenolic compound is t-amylphenol, o-chloro-p-benzylphenol, p-chloro-m-xylenol, or ophenyl phenol. Most preferably, the phenolic compound is p-chloro-m-xylenol

(PCMX).

•Examples of suitable isothiazolinones include 2-alkyl-4-isothiazoline-3-ones.

Preferred isothiazolinones include 2-(n-octyl-4-isothiazolin-3-one), 2-cyclohexyl-3-isothiazolinone, 4,5-dichloro-2-(n-octyl-4-isothiazolin-3-one), chloro-2-methyl-4-isothiazolin-3-one, and 2-methyl-4-isothiazolin-3-one.

o:oo When one or more further antimicrobial components are used the amount of the antimicrobial of the invention may be as described above. In the case of further antimicrobials the amounts used will depend on the type of antimicrobial.

Typical amounts of the preferred additional antimicrobials are: a phenol in an amount of 0.001 to an isothiazolinone in an amount of 0.001 to 1%; glutaraldehyde in an amount of 0.2 to 4% and alkanol in an amount of 20 to 99.9%.

In accordance with a further aspect of the invention we provide a composition for treatment or prophylaxis of gastrointestinal disease in poultry comprising an antimicrobial polymer as hereinbefore described and a further chemotherapeutic agent wherein the further chemotherapeutic agent is adsorbed onto the antimicrobial.

W annspeesmcheeq A. Apbn doc The adsorption will typically reduce membrane penetration of the further chemotherapeutic. The suitable chemotherapeutics for use in this embodiment are those which exhibit a significant reduction in membrane penetration when admixed with the polymeric antimicrobial. Preferably the penetration is inhibited by a factor of at least The useful chemotherapeutic agents for use in this aspect of the invention include antibiotics for treatment of gastrointestinal disease.

The use of chemotherapeutics in combination with the polymeric antimicrobial reduces membrane penetration of the chemotherapeutic thereby reducing systemic side effects and providing more targeted therapy. In many cases odour is also reduced.

Examples of chemotherapeutics for treatment of gastrointestinal disease include antibiotics and anticancer agents.

Examples of antibiotics which may be used in combination with the antimicrobial polymer include tetracyclines, penicillins, aminoglycosides, sulfa drugs, cephalosporins and nitrofurans.

The antibiotics may be conventional antibiotics used to treat infections of the gastrointestinal tract.

The improvement weight given provided by the composition of the invention is generally at least 0.25% over 14 days, preferably at least 1% and most preferably at least The invention will now be described with reference to several Examples, which should not be construed as limiting the scope thereof.

We~nnie\speeiaemeqAu Au Adoc 16 BIOCIDAL TEST Dissolve sample with 1% by weight aqueous sodium bicarbonate to obtain the required concentration (unless specified to the contrary, 0.125% by weight in polymer). Weigh 19.9g of diluted sample into a sterile jar and inoculate with 0.1 mL of 107-108 cfu of Ps.aeruginosa and mix. At specified time-intervals, transfer 1 mL of inoculated sample to 9 mL of Letheen broth and vortex. Plate out serial 1 in 10 dilutions. Pour with trypticase soy agar. Incubate 3 days at 37 0

C.

The invention will now be described with reference to the following examples. It is to be understood that the examples are provided by way of illustration of the invention and that they are in no way limiting to the scope of the invention.

Example 1 The example describes a method of preparing a poly(2-propenal, 2-propenoic acid) by oxidation of a solid acrolein polymer in air. This poly(2-propenal, 2propenoic acid) is the preferred method of preparing a starting material for use in the method of the invention. Water (720 mL at ambient temperature, about 0 C) and acrolein (60g freshly distilled, plus hydroquinone added to 0.25% w/w) were placed in an open beaker, within a fume cupboard, and very 20 vigorously stirred, mechanically. Then, 0.2 M aqueous sodium hydroxide (21.4 mL) was added to bring the pH to 10.5-11.0.

The solution immediately turned a yellow typical of the hydroquinone anion and within a minute, the colour had disappeared and the clear solution became 25 milky.

About 1 minute later, precipitation of a white flocculent polymer began, and appeared complete within 15-30 minutes. The precipitate was filtered and washed with water (250 mL), dried at room temperature upon filter papers for 2 days (yield 25g), then spread as a thin layer in glass petri dishes and heated at 400 C/8 hours. This heating was continued at the following schedules 5 0 0 hours 650 C/4 hours 750 C/18 hours 840 C/24 hours.

W(ciie.peS dWenn eq Am APW Mos 17 It is envisaged that this method may be scaled-up to include, eg the stepwise addition of acrolein, in a closed vessel, and followed by more rapid drying (compare example 3).

Typically, a solution of the resulting poly(2-propenal, 2-propenoic acid) was prepared by adding 2g of the subject polymer, with stirring over 15-30 minutes, to a 1% w/w aqueous sodium carbonate solution (100 mL), and then diluted as required. Such solutions were perfectlyclear.

Example 2 of poly(2-propenal, 2-propenoic acid) was dissolved in 64g polyethylene glycol 200 and combined with 31g of a 0.71 w/w solution of sodium carbonate. The solution (apparent pH=5.8) was retained at room temperature 15 Table 1 l* The sample was examined by 1 H Nuclear Magnetic Resonance (NMR) spectra at 600 MHZ.

The spectra of the compounds and the assignment of signals is shown in the table below.

of H NR Spectra Table of 1 H NMR Spectra 25 6 (ppm) Groups 1.1-2.9

-CH

2 3.3-4.8 -CHO-, -CH 2 0- 3.6 -CH 2 0- (PEG) 4.9 HOD 5.1-5.5

=CH

2

-OH

5.7-6.0 -CH= 9.3-9.6 -CH=O W.Wuronep edeshem Au APPM doc Example 3 This Example demonstrates the preparation of an acrolein polymer for use in accordance with the invention.

0.8% wlw Sodium Hydroxide Place 9.90 kg of deionised water in a 10L stainless steel vat and add 0.08 kg sodium hydroxide to the water and stir until dissolved.

2.0 Polymerisation Place 100.1 kg of deionised water in a 200L stainless steel vat and add 4.99 kg of the 0.8% w/w sodium hydroxide solution to the 200L vat.

Equilibrate the solution to 15 200 C. Simultaneously add 20 kg acrolein monomer and the remaining 0.8% w/w sodium hydroxide solution to the 200L vat at a rate over 1 hour such that the pH remains at 10.5 -11.0, and the temperature does not rise above 30° C. Continue the polymerisation for a further 90 minutes.

Washing 20 Filter/centrifuge the polymerisation mixture and wash the polymer with deionised water until the pH of the wash water is less than 7.0. The approximate yield is 8 kg.

Drying Dry the Step 1 2 3 4 polymer in air, Time 2 hrs 1 hr 1 hr 1 hr 2 hrs then heat in an oven using the following program.

Temperature 25 0

C

40 0

C

700 C 75 0

C

850 C W.*acan.1spees%~meq Au Applkdoc 19 Dissolution Place 400L of water in a 500L vat and add 4 kg of sodium carbonate and stir until dissolved. Slowly add 8 kg of dry, heated polymer and stir for thirty minutes.

The resulting polymer was found to have an approximate solubility of 95% w/w in 1% w/w sodium carbonate.

Example 4 This example examines the use of the dry poly(2-propenal, 2-propenoic acid) polymer of Example 3 which promotes growth in chickens.

Chickens treated of the antimicrobial were compared with a control group according to the following procedure: In the trial 20 Cob chickens (Line 53), day old were purchased from a commercial hatchery. They were weighed, sexed and randomly assigned into adjacent pens in a room of an isolated animal house. There was an even distribution of male and female chickens. Water and feed were available ad libitum. The diet was a commercial crumble (Chick Starter, Milne Feeds: 18% crude protein) with a coccidiostat present (125 ppm Dinitolomide).

Ten chickens were administered the formulation of 0.1% w/w of the antimicrobial from Example 3 in the water for 14 days through static drinkers; dose rate of 30 mg/kg/day. The other ten chickens were the Control Group.

Both groups of chickens were weighed on days 0, 4, 7, 11 and 14. At the completion of the trial all chickens were euthanised, and the treated chickens were autopsied post mortem. A thorough gross examination of the thoracic and abdominal cavities was performed.

W*jw,,%sopedesrhemeq Au Ap.do

RESULTS:

Table 2 Weight gained during trial with the antimicrobial of Example 3 Day Control Group Treatment Group Differences between (Average Weight in g) (Average Weight in g) groups 0 42.5 42.5 0 4 65.0 72.5 11.5 7 98.5 98.0 11 145.5 148.5 2.4 14 185.5 200.5 8.1 The treatment group had measurably greater weight gains at the end of the 14day period in comparison to the control group.

At the completion of the trial, at post-mortem, no clinical or pathological signs of toxicity were evident at this gross examination in the treated group of chickens.

0 In a similar way the poly(2-propenal, 2-propenoic acid) may be used as a prophylactic measure to control infections such as clostridia, coccidia, salmonella and E.coli in chickens and boilers.

9* a W.Wanniespeaesce meq Au Auptn~oc

Claims (19)

1. A method of promoting weight gain or treating or preventing gastrointestinal disease in poultry comprising adding to the drinking water of the poultry an antimicrobial composition comprising an acrolein polymer having repeating units of formula I: H C CH 2 Q (I) 0 H or this unit in its hydrated, hemi-acetal or acetal form and in an amount of from 0.0001% to 70% by weight based on the total weight of the 10 antimicrobial composition and a carrer therefor selected from the group consisting of a controlled release entity, water, an alkanol, polyhydric *alcohols (including diols) and mixtures thereof.

2. A method according to claim 1, wherein the acrolein polymer is poly(2- propenal, 2-propenoic acid) and wherein the acrolein polymer comprises in the range of from 0.1 to 5 moles of carboxyl groups per mole of acrolein polymer. **0 S3. A method according to claim 1, wherein the acrolein polymer is produced S 20 by ionic homopolymerisation of acrolein and oxidation of the resulting polymer in air to provide in the range of from 0.1 to 5 moles of carboxyl groups per mole of acrolein polymer.

4. A method according to claim 1, wherein the polyhydric alcohol is selected from the group consisting of alkylene glycols, polyalkylene glycols and mixtures thereof. A method according to claim 1, wherein the polyhydric alcohol is polyethylene glycol. x aMssMIaelsspedA 22

6. A method according to claim 1, wherein the polymeric alcohol is polyethylene glycol of molecular weight in the range of from 200 to 2000.

7. A method according to claim wherein the antimicrobial composition is added to the poultry feed or drinking water in an amount of from 0.0001 to 10% by weight of acrolein polymer in the water.

8. A method according to claim 1, wherein the antimicrobial is mixed with poultry drinking water in an amount to provide a concentration of acrolein polymer in the range of from 0.01 to 2% by weight.

9. A method according to claim 1, wherein the antimicrobial composition is administered in the water of poultry to provide a daily dose of the acrolein polymer in the range of from 0.01 to 500 mg/kg/day.

10. A method according to claim 9, wherein said daily dose is in the range of from 0.05 to 50 mg/kg/day.

11. A method according to claim 10, wherein the daily dose is in the range of 20 from 0.1 to 40 mg/kg/day. *e00

12. A method according to claim 1, wherein the antimicrobial is co- administered with coccidiostat selected from the group consisting of nitrocarbanilide, quinoline, pyridon, guanidine, quinoxaline, toltrazural, 25 potentiated sulfa drugs and ionophore with carbanilide.

13. A method according to claim 1, wherein the poultry are suffering necrotic enteritis or coccidiosis.

14. An antimicrobial growth promoting composition for use as a concentrate for addition to drinking water comprising poly(2-propenal, 2-propenoic acid) and a carrier therefor comprising a polyhydric alcohol. 23 An antimicrobial growth promoting composition according to claim 14, wherein the poly(2-propenal, 2-propenoic acid) includes from 0.5 to mole of carboxyl groups per kilogram of poly(2-propenal, 2-propenoic acid).

16. An antimicrobial composition according to claim 14 or claim 15, wherein the poly(2-propenal, 2-propenoic acid) is present in an amount in the range of from 0.1 to 50% by weight of the concentrate.

17. An antimicrobial composition according to any one of claims 14 to 16, wherein the polyol is polyethelyne glycol of molecular weight in the range of from 200 to 2000.

18. An antimicrobial composition according to any one of claims 14 to 17, 15 wherein the polyol is present in an amount of from 5 to 90% by weight.

19. An antimicrobial composition according to any one of claims 14 to 17, wherein water is present in an amount of from 5 to 90% by weight. 20 20. An antimicrobial composition according to any one of claims 14 to 19, wherein the composition has a pH of above 4.

21. A method according to any one of claims 1 to 13, wherein the antimicrobial composition is mixed with the drinking water of chickens 25 and provides an improvement in weight gain in the chickens of at least 0.25% over a period of 14 days.

22. A method of any one of claims 1 to 13 or claim 21 of promoting weight gain or treating or preventing gastrointestinal disease in poultry comprising adding to the drinking which method is substantially as herein described with reference to any one of the Examples. 24

23. An antimicrobial growth promoting composition of any one of claims 14 to substantially as herein described with reference to any one of the Examples. Dated: 28 May 2004 PHILLIPS ORMONDE FITZPATRICK Attomrneys for: /V A CHEMEQ LTD oO gee *oeo oooo*o e o oe oooo oooo oo o e oooo *°oo oooo