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RIRDC Completed Projects in 2006-2007 & Research in Progress as at June 2007
To Horses Research in Progress
2.4 HORSES - COMPLETED PROJECTS in 2006-2007 PROJECT No PROJECT TITLE RESEARCHER PHONE ORGANISATION To improve the management of growing and developing horses UMU-33A Risk factor for gastric ulceration in thoroughbred racehorses A/Prof Guy Lester (08) 9360 7676 Murdoch University To improve the overall health and welfare of the horse RAS-1A An investigation into the detection of three common veterinary pharmaceuticals Dr John Vine (03) 9376 6760 Racing Analytical Services Ltd To keep Australia free from major exotic equine disease out-breaks and limit the impact of endemic diseases UCS-35A Investigating the role of impaired glucose uptake in laminitis Dr Martin Sillence (02) 6933 2205 Charles Sturt University UM-71A Integrated pest management for the horse farm Prof Ary Hoffmann (03) 9479 2769 La Trobe University US-108A Prospective Longitudinal Study of disease on Equine Stud Farms Dr James Gilkerson 0409 583 169 The University of Melbourne Other UQ-111A Epaxial musculature and its relationship with back pain in the horse Dr Catherine McGowan (07) 5460 1521 University of Queensland AUR-1A National standards for track monitoring, assessment and design Mr Arthur Stubbs (03) 9844 1135 Australian Racecourse Managers Association Inc
2.4 HORSES - COMPLETED PROJECTS 2005-06 PROJECT No
PROJECT TITLE RESEARCHER PHONE ORGANISATION Information Technology for the Horse Industry US-124A Communications and information programs for the horse industry Ms Shirley Ray (02) 9352 6932 University of Sydney To improve the management of growing and developing horses US-129A Risk factors for injuries in thoroughbred racehorses during commercial training Prof David Evans (02) 9351 2474 University of Sydney To improve the overall health and welfare of the horse OFF-1A The production of a poster and booklet on poisonous weeds for horses Ms Mellisa Offord (02) 8901 0622 To more effectively quantify the environmental impact on the horse industry UQ-119A Transfer of weeds to Qld native forests on horses hooves Dr. Christopher Pollitt (07) 3365 2063 The University of Queensland Respiratory Diseases-Improving the Respiratory Health of Horses UM-67A Effects of Stud Management on Ecology of Virulent Rhodococcus equi and Further studies of the ecology of virulent R. equi on horse studs - 2002 stud season Dr Glenn Browing (03) 8344 742 University of Melbourne Lameness and Limb Injury-Developing More Effective Methods for Prevention, Diagnosis and Treatment UQ-100A Pasture fructan concentration as a cause of equine laminitis Dr. Christopher Pollitt (07) 3365 2063 The University of Queensland Other EPS-1A Prototype Environmental Management System (EMS) for the horse keeping community - implementation, auditing and monitoring Ms Jacqueline Frizenschaf (08) 8139 9919 Environment Protection Authority SA Completed Projects - To improve the management of growing and developing horses
Completed Projects - To improve the overall health and welfare of the horse
Completed Projects - To improve the overall health and welfare of the horse
Project Title: Penetration of pharmacological agents through equine skin RIRDC Project No.: UQ-114A Researcher: Paul Mills and Sheree Cross Organisation: School of Veterinary Science University of Queensland
Phone: (07) 3365 2964 Fax: (07) 3365 1255 Email: p.mills@uq.edu.au Objectives ·13 To develop in vitro methodologies to measure drug movement through equine skin ·14 To measure the regional differences (e.g. thorax vs axilla vs lower leg) in drug penetration
·15 To measure transdermal penetration of drugs of interest to the equine industry, including non-steroidal anti-inflammatory drugs (NSAIDs), corticosteroids and analgesics (e.g. fentanyl)
·16 To determine the effects of vehicles (e.g. propylene glycol) on penetration of drugs in the horse
·17 To determine the effects of skin damage (e.g. rashes) and altered microenvironment (skin cleansers) on transdermal drug movement in the horse.
Background Topical medications are increasingly used in all species, including the horse. It is important to understand that there are significant species differences between the rate and extent that any drug formulation will move through skin. This means that formulations developed for one species may not have the same amount of drug (more or less) available after topical application. This can lead to either ineffective treatments or toxicity. It is also important to understand transdermal drug penetration when entering horses in competition because many compounds can move through skin and may be detected in blood and urine samples, leading to infringement of the rules of competition. This project was designed to address this lack of basic data concerning transdermal drug penetration in the horse. Research In vitro techniques to characterise how much and how quickly a range of clinically relevant drugs can pass through horse skin. The same techniques to then investigate regional differences (does drug penetration differ if applied at a different site), the effect of vehicles (what the drug is dissolved in) and the effects of skin damage on transdermal drug penetration. An in vivo model was then trailed to permit investigations relating in vitro results to the living horse. Outcomes Anti-inflammatory drugs such as hydrocortisone and methylsalicylate penetrate faster and to a greater extent through skin from the leg, which is useful if applying these drugs for anti-inflammatory activity in the legs of horses. Conversely, fentanyl (pain relief) penetrates better through upper body regions which is where fentanyl patches are normally applied. There are significant effects of the vehicle on the transdermal penetration of testosterone in the horse, with vehicles containing ethanol or propylene glycol (both commonly found in topical creams and gels) associated with greater drug amounts moving through the skin. An important finding was the effect of damage or change to the skin surface created using common clinical approaches to treating skin, including shaving, application of adhesive tape and cleaning skin which all significantly enhanced the penetration of methylsalicylate through skin.
Implications Any stakeholder in the equine industry, from trainers, owners, veterinarians, officials and regulators should be aware that there are significant species differences between how much and how fast a particular formulation will penetrate skin, meaning that a formulation developed and registered for one species will be unlikely to have the same effect and safety margin when applied to another species, including the horse. Also, horse entering into competition should be aware of the potential for the appearance of drugs in blood and urine collected from their horse following topical application which may lead to infringement of the rules of competition. Stakeholders should also be aware that there are regional differences, meaning that a formulation applied to one part of the body may have a different level of effect if applied elsewhere. Different formulations of the same drug can have significant effects on how much of the drug actually penetrates through the skin and is available for whatever purpose it was designed. Most importantly, changes in the integrity of the skin, such as rashes, abrasions, skin disease or the use of agents to clean the skin, can substantially alter the amount and rate of active drug uptake.Publications Mills P.C. and Cross S.E. (2006) The effects of equine skin preparation on transdermal drug penetration in vitro. Can J Vet Res 70(4):317-20. Mills P.C. and Cross S.E. (2006) Transdermal Drug Delivery: Basic Principles for the Veterinarian. Vet J 172(2): 218-233.
Mills P.C. and Cross S.E. (2006) Regional differences in transdermal penetration of fentanyl through equine skin. Res Vet Sci. (in press).
Mills P.C. (2006) Vehicle effects on the penetration of testosterone through equine skin. Vet.Res.Comm. (in press).
Mills P.C. and Cross S.E. (2006) Regional differences in the in vitro penetration of hydrocortisone through equine skin. J Vet.Pharm.Ther. 29: 25-30.
Mills P.C. and Cross S.E. (2006) Regional differences in the in vitro penetration of methylsalicylate through equine skin. Vet.J. (doi 10.1016/j.tvjl.2005.08.023).
Mills P.C., Magnusson B.M. and Cross S.E. (2005) Penetration of a topically applied nonsteroidal anti-inflammatory drug into local tissues and synovial fluid of dogs. Am.J.Vet.Res. 66(7): 1128-1132.
Mills P.C. and Cross S.E. (2006). Penetration of Pharmacological Agents through Equine Skin RIRDC Publication No 07/092.
Completed Projects - To keep Australia free from major exotic equine disease out-breaks and limit the impact of endemic diseases
Completed Projects - To keep Australia free from major exotic equine disease out-breaks and limit the impact of endemic diseases
Completed Projects – Respiratory Diseases - Improving the Respiratory Health of Horses
Completed Projects – Other
Completed Projects – Other
Completed Projects 2005-2006 – Information Technology for the Horse Industry
Completed Projects 2005-2006 - To improve the management of growing and developing horses
Completed Projects 2005-2006 - To improve the overall health and welfare of the horse
Completed Projects 2005-2006 – To more effectively quantify the environmental impact on the horse industry
Completed Projects 2005-2006 – Respiratory Diseases – Improving the Respiratory Health of Horses
Completed Projects 2005-2006 – Lameness and limb injury – Developing more effective methods of prevention, diagnosis and treatment
Completed Projects 2005-2006 - Other