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RIRDC Completed Projects in 1999-2000 and

Research in Progress as at June 2000

Sub-Program 3.5

HORSES

August 2000 RIRDC Publication No 00/91

© 2000 Rural Industries Research and Development Corporation. All rights reserved. ISBN 0 642 58122 3 ISSN 1440 6845 "RIRDC Completed Projects in 1999-00 and Research in Progress as at June 2000 - 3.5 Horses Publication No 00/91 The views expressed and the conclusions reached in this publication are those of the author and not necessarily those of persons consulted. RIRDC shall not be responsible in any way whatsoever to any person who relies in whole or in part on the contents of this report. This publication is copyright. However, RIRDC encourages wide dissemination of its research, providing the Corporation is clearly acknowledged. For any other enquiries concerning reproduction, contact the Publications Manager on phone 02 6272 3186. RIRDC Horses Research Manager Professor Reuben Rose RIRDC Level 1, AMA House 42 Macquarie Street BARTON ACT 2600 PO Box 4776 KINGSTON ACT 2604 Phone: 02 9351 6935 Fax: 02 9660 1548 Email: [email protected] RIRDC Publications Manager Cecile Ferguson Rural Industries Research and Development Corporation Level 1, AMA House 42 Macquarie Street BARTON ACT 2600 PO Box 4776 KINGSTON ACT 2604 Phone: 02 6272 3186 Fax: 02 6272 5877 Email: [email protected] Website: http://www.rirdc.gov.au

Published in August 2000 Printed on environmentally friendly paper by Canprint

Foreword This year RIRDC has produced Research in Progress, June '00, which contains short summaries of continuing projects as well as those that were completed during 1999-00 for all of the Corporation’s 20 program areas. The complete report on all the programs is only available in electronic format on our website at http://www.rirdc.gov.au The following report is a hardcopy extract covering Sub-Program 3.5. It contains all entries from continuing and completed horse research projects funded by RIRDC. Our horse program aims to assist in developing the Australian horse industry and enhancing its export potential. This report is the newest addition to our extensive catalogue of almost 400 research reports, videos and CD-Roms of projects supported by RIRDC. Please contact us for the latest publications catalogue or view it on our website: • downloads at www.rirdc.gov.au/reports/Index.htm • purchases at www.rirdc.gov.au/eshop

Peter Core Managing Director Rural Industries Research and Development Corporation

Contents

3.5 HORSES

COMPLETED PROJECTS

PROJECT No

PROJECT TITLE RESEARCHER PHONE ORGANISATION PAGE No

AHI-1A An assessment of the extent, nature and source of support for an R&D levy for the Australian horse industry

Ms Jan Miller (03) 5964 8148 Australian Horse Industry Council 6

DAV-118A Improved pastures: more than just grass for horses to exercise on?

Ms Angela Avery (02) 6030 4500 Department of Natural Resources & Environment

7

DAV-156A Drought feeding information bulletin for the horse industry

Ms Angela Avery (02) 6030 4500 Department of Natural Resources & Environment

8

FLP-1A Supporting learning in the horse industry Mr Laurie Field (02) 9498 8278 Field Learning Pty Ltd 9 IEC-1A Equine Air Transport Project 2000 Dr Desmond Leadon (04) 5886266 Irish Equine Centre 10 PTP-13A 4th Australian Racecourse Managers' Conference –

1999 Mr Arthur Stubbs (03) 9844 1135 Primary Tasks Pty Ltd 11

UCS-22A Pasture intake and selectivity by grazing horses Mr Michael Friend (02) 6933 4006 Charles Sturt University 12 UM-29A Molecular epidemiology of Rhodococcus equine Dr Glenn Browning (03) 9344 7342 The University of Melbourne 13 UQ-45A Nutrition of grazing broodmares, their foals and

young horses Dr Neil McMeniman (07) 3365 1108 The University of Queensland 15

UQ-46A Assessment and prevention of toxicity from indospicine contaminated horsemeat

Dr Michael Pass (07) 3365 3127 The University of Queensland 16

US-50A Communication and information programs for the horse industry

Prof Reuben Rose (02) 9351 6936 The University of Sydney 17

US-52A Biomechanical and biochemical response of equine superficial flexor tendon to training and injury

Mr Andrew Dart (02) 4655 2000 The University of Sydney 18

US-53A Respiratory ventilation and tracheal sounds in horses with airway disease

Dr David Evans (02) 9351 2474 The University of Sydney 19

US-77A Training and Fitness in Athletic Horses Dr David Evans (02) 9351 2474 The University of Sydney 20 US-81A How well are we meeting the training needs of the

horse industry? (Workshop) Prof Reuben Rose (02) 9351 6936 The University of Sydney 21

USA-6A Diagnosis of and protection against infections caused by Rhodococcus equine

Dr Mary Barton (08) 8302 2933 University of South Australia 22

3.5 HORSES RESEARCH IN PROGRESS

PROJECT

No PROJECT TITLE RESEARCHER PHONE ORGANISATION PAGE

No UCS-24A Health and performance of pony club horses

(Stage 1) Dr Petra Ecke (02) 6933 2426 Charles Sturt University 23

UM-40A Epidemiology of equine rhinovirus type 2 (ERhV2) Prof Michael Studdert Dr Carol Hartley

(03) 9344 7373 The University of Melbourne 24

UM-47A Effects of stud management on ecology of virulent Rhodococcus equine

Dr Glenn Browning (03) 9344 7342 The University of Melbourne 25

UMA-15A Improved vaccine strategies for management of equine herpesvirus diseases

A/Prof Millar Whalley A/Prof Daria Love

(02) 9850 8200 (02) 9351 2454

Macquarie University The University of Sydney

26

UMO-26A Analysis of horse breeding efficiency in Australia Dr Angus McKinnon (03) 5829 9566 Goulburn Valley Equine Hospital 27 UMU-22A Identification of infectious respiratory disease in

horses as a basis for better management of cases A/Prof Graham Wilcox (08) 9360 2448 Murdoch University 28

UMU-24A Investigation into radiographic changes in the carpus (C3) in racehorses

Dr Catherine Steel (08) 9360 2356 Murdoch University 29

UNE-62A Safe and effective grain feeding for horses Prof James Rowe (02) 6773 2225 University of New England 30 UQ-71A Novel anti-inflammatory drugs to treat inflammatory

diseases in horses Dr Stephen Taylor (07) 3365 3124 The University of Queensland 31

UQ-72A Nutritent intake and growth of young horses Dr Neil McMeniman (07) 3365 1108 The University of Queensland 32 UQ-73A Repeatability and reliability of Brochoalveolar

Lavage (BAL) in the horse Dr John Thornton Ms Joanne Hamilton

(07) 3365 2917

The University of Queensland 33

UQ-75A The pathogenesis and prevention of equine laminitis Dr Michael Pass Dr Christopher Pollitt

(07) 3365 3127 (07) 3365 2063

The University of Queensland 34

US-82A A Longitudinal Cohort Study of Inflammatory Airway Disease in Racing Thoroughbreds

Dr Jennifer Hodgson (02) 4655 0745 The University of Sydney 35

US-84A An epidemiological study of risk factors for shin soreness in Thoroughbred racehorses

Dr David Evans (02) 9351 2474 The University of Sydney 36

USU-1A Assessment and prevention of toxicity from indospicine-contaminated horsemeat

Dr Michael Pass (07) 5430 2840 University of the Sunshine Coast 37

3.5 Horses

Completed Projects

Project Title

An assessment of the extent, nature and source of support for an R&D levy for the Australian horse industry

RIRDC Project No.:

AHI-1A

Researcher: Ms Jan Miller Organisation: Australian Horse Industry Council

20 Centre Road YELLINGBO VIC 3139

Phone: (03) 5964 8148 Fax: (03) 5964 8402 Objectives

• To provide an assessment of the extent, the nature and sources of support

for the proposed R&D levy for the horse industry and to provide an analysis of the basis for this support and any reasons for opposition.

• To ensure that the industry organisations and other participants in the industry agree to the coverage and details for the supporting evidence.

Background To address the problems associated with maintaining and growing a diverse and

unique industry that is the horse industry, evaluation and research of methods to secure a future for this industry by investment in R&D is necessary. The economic impact of the horse industry is substantial and there are more then 350,000 equine association memberships spread amongst 56 known horse breeds. The horse population is in excess of 1.3 million in Australia

Research

A widespread analysis and investigation of the horse industry was undertaken which included face to face meetings with key industry groups and interviews with key individuals.

Outcomes

There was widespread support for the concept of research and development within the horse industry. However it was clear that continuing major effort needs to be put into communicating the results of R&D projects to the horse industry

Implications

Currently the industry is responsible for own destiny and relies heavily on major groups to support the AHIC with membership and assistance, and the RIRDC R&D Equine Program with voluntary funds matched by the government is critical to secure results for the Australian horse industry. There needs to be however, a statutory method for support the critical R&D rather than leaving this to voluntary contributions by different industry groups

Project Title

Improved pastures: more than just grass for horses to exercise on?

RIRDC Project No.:

DAV-118A

Researcher: Ms Angela Avery Organisation: Department of Natural Resources & Environment

RMB 1145 Chiltern Valley Road RUTHERGLEN VIC 3685

Phone: (02) 60304500 Fax: (02) 60304600 Objectives

• To determine the extent to which different pasture types stocked at

different rates can meet the growth requirements of young horses. • To compare supplementary feeding ('normal' practice) with pasture-based

feeding systems.

Background In Australia traditional feeding practices tend to be based on concentrated feeding with pasture supplementation. This is in contrast to the successful New Zealand practice of pasture based feeding. Other extensive animal production systems recognise pasture as the most economic feed providing a competitive advantage in global markets. While a shift by the horse industry to a feeding system based on pasture is unlikely due to the diversity of environments in Australia and high stocking rates in some regions the nutritional role of pasture can be significantly increased, with concomitant savings in feeding costs.

Research

The project consisted of one replicated grazing experiment conducted at Rutherglen in north east Victoria. The grazing experiment evaluated the extent to which different temperate pasture types stocked at different stocking rates could meet the growth requirements of the young horse. Two pasture types, improved (phalaris, annual ryegrass and subterranean clover with lime and above maintenance fertiliser) and unimproved (annual grasses, weeds and subterranean clover and maintenance fertiliser) at two stocking rates, low and high were compared to weanlings fed a supplement formulation determine by industry. Pasture and horse measurements were taken every 28 days from April to December in 1998 and April to November in 1999. Fillies were measured in 1998 for 252 days (April 6 to December 14) and colts in 1999 for 201 days (April 17 to November 4). Foal measurements included weight gain, height at the wither and hip, girth circumference, metacarpal dimensions, condition score and parasite burden. Pastures were measured for herbage mass, composition, percentage green and quality. A basic economic analysis of the different foal raising systems was also undertaken.

Outcomes

The average weight gain of the foals were 0.73 and 0.77 kg/day in 1989 and 1999. The NRC Nutrient requirement of horses (1989) recommends a growth rate of 0.65 (moderate) to 0.85 (rapid) kg/day for 6 month old weanlings (mature body size 500 kg) and 0.50 (moderate) to 0.65 kg/day (rapid) for yearlings. The average growth rates achieved in this experiment therefore fell between the NRC recommendations for moderate and rapid growth. Hand-fed foals in both years did not exhibit greater growth than the foals grazing pasture. This indicates that at low stocking rates pastures are able to support acceptable foal growth rates. The ration fed to the hand-fed foals was designed to achieve an average growth rate of 0.70 kg/day. While this growth rate is within the range of NRC 1989 recommendations for weanling and yearling growth there may be some debate by industry wether 0.70 kg/day is an acceptable growth rate to produce a marketable yearling.

Implications This study concludes that at low to moderate stocking rates young foals can be

produced to acceptable industry standards on pasture. Basic economics highlight a significant opportunity for the horse breeding industry to substantially reduce production costs. Foal raising systems should not be considered as only pasture or only hand feeding, the greatest benefit lies in the ability to integrate pasture and concentrates, with concentrate levels being determined by pasture nutrient shortage.

Publications

Avery, A.L. (1998). Management of pastures, optimising pasture for the best most effective nutrition. In: “Equine Nutrition Proceedings of the Post Graduate Committee in Veterinary Science, University of Sydney, 312, 35-49.

Project Title

Drought feeding information bulletin for the horse industry

RIRDC Project No.:

DAV-156A

Researcher: Ms Angela Avery Organisation: Department of Natural Resources & Environment

RMB 1145 Chiltern Valley Road RUTHERGLEN VIC 3685

Phone: (02) 60304500 Fax: (02) 60304600 Objectives

• To prepare a document that will provide information for the horse industry

on feeding and horse management in times of drought.

Background Droughts are very much part of agriculture in Australia. Horse owners, like other managers of livestock, need to prepare for times of dry conditions and drought. Other animal industries have prepared information available to assist them through drought, until the completion of this manual there was no such information available to the horse industry. A practical guide on horse feeding and management during drought was needed to help owners break the daunting planning phase of a threatening drought down to manageable steps. This manual will enable horse owners to get through drought in the most economic and stress-free way without horses, pasture or soil resources suffering.

Research

This project involved literature review and consultation with experts on drought, horse and pasture management to develop the information in the drought manual.

Outcomes

A practical relevant manual that will assist horse owners manage dry and drought conditions. Support for the horse industry during drought conditions.

Implications

The horse industry in Australia will be better able to manage their enterprises during drought leading to reduced costs, animal health problems and environmental degradation. The wider community will also see the industry as being responsible and pro-active towards drought.

Publications

The main objective of this project was to publish information on drought for the horse industry. This information is to be printed by RIRDC as a research publication.

Project Title

Supporting Learning in the horse industry

RIRDC Project No.:

FLP-1A

Researcher: Mr Laurie Field Organisation: Field Learning Pty Ltd

29 Pearson Avenue GORDON NSW 2072


• To develop a better understanding of the ways in which various sectors of

the equine R&D industry learn. In doing so, it will highlight opportunities for supporting learning within the industry.

Background In the horse industry, while a lot of effort goes into courses, publications, web-

sites, and seminars dealing with horse care and the treatment of illness, surprisingly little is known about the learning needs and expectations of people in the industry. The result is that while there is a great deal of information available to people within the horse industry, we actually know very little about how or why people in the industry use this information. This study was an attempt to address this issue.

Research

Data was derived from questionnaires and interviews covering a wide sample of industry sectors across Australia.

Outcomes & Implications

A great deal of learning within the horse industry occurs informally. People seek information from a wide variety of sources, sometimes in a systematic way, but more often relying on word-of-mouth and casual observation. While natural and flexible, this style of learning can result in perpetuation of myths and gaps in understanding. The RIRDC Equine program provides valuable sources of accurate information about horse care and treatment of illness. Their newsletter, web-site and publications all attracted very favourable comment. More generally, there appears to be some reluctance within the industry to see learning and development as part of a long-term strategic focus of businesses and the industry as a whole. Hence, some of the data suggests limited commitment to employee development in the area of horse care and treatment of illness, and a reluctance to pay for learning. While there is much activity in the area of formal training for people in the horse industry, there is still considerable potential to improve the climate for learning as part of everyday work.

Publications

RIRDC research report Supporting Learning in the Horse Industry: The Industry Speaks.

Project Title

Equine Air Transport Project 2000

RIRDC Project No.:

IEC-1A

Researcher: Dr Desmond Leadon Organisation: Irish Equine Centre

Johnstown, Naas, Co. Kildare, Ireland Phone: 0011 045 886266 Fax: 0011 045 866273 Objectives

To provide information on the key issues that result in problems related to

horse transport. To provide recommendations for minimising the adverse effects of horse

transport particularly transport by air.

Background It is difficult to get accurate statistics on horse transport. However, to give some insight into the numbers internationally, 318,952 horse movements across European Union national frontiers were recorded by the EU Eurostats office in 1992, and 605,900 Thoroughbred horses could have been transported for either racing or breeding in 37 of the major racing countries in 1990s. Transport can be associated with ill-health in horses and this publication sets out some of the current information.

Research

The author is the most experienced veterinarian in the world in the area of land and air transport. The approach taken in preparation of this booklet was to review all the information available in the scientific literature and to distil information obtained from a number of scientific studies of horse transport. These were then applied in a “user-friendly” format.

Outcomes

The key areas recommended for practical benefit for the horse industry are:

1. Journey Planning 2. Training and familiarisation 3. Water and electrolytes 4. Bodyweight 5. Respiratory health and disease 6. Medication

Implications

Recommendations are made as to strategies before and after transport to minimise ill-health. The recommendations in this RIRDC publication are in essence equally applicable in general terms, to both road and air transport. In many ways, it makes little difference to horses whether they are being transported in a vehicle that has wings or one that has wheels. Providing good health care for transported horses requires focus prior to travel, during the journey and after arrival

Publications

Horse Transport, RIRDC, 1999

Project Title

4th Australian Racecourse Manager’s Conference – 1999

RIRDC Project No.:

PTP-13A

Researcher: Mr Arthur Stubbs Organisation: Unit 58, Level 2

Carlton Clocktower Complex 247 Drummond Street CARLTON VIC 3053


• Improvement of inter-club communication and education on issues of

racetrack care and maintenance for the development of effective, overall strategies for racecourse development.

Background A survey of grass racecourses in Australia in 1995 (RIRDC Project TGT-1A)

found a wide variation in the level of racecourse management expertise and technical knowledge, as well as a sense of isolation by many racecourse managers and an expressed need for more information relevant to their jobs. This led to Racecourse Managers’ Conferences being held in the following three years, at Rosehill, Moonee Valley and Doomben, each attended by many racecourse managers from most States of Australia and New Zealand. The success of these conferences led to the 4th Conference at Morphettville on April 13-15,1999, with the theme, “Managing Racecourses”.

Outcomes 93 people attended the conference, including 70 racecourse managers and staff from throughout Australia and New Zealand, plus suppliers and consultants to the racecourse industry, research workers and turf specialists. The conference was again very well received and delegates recommended that a similar forum be organised for 2000. It was considered that the objective had been achieved through the combination of paper presentations, two workshops, input from an American racecourse manager, inspections of three local racecourses and a racehorse stud, and general liaison between racecourse managers from a wide range of situations.

Implications The conference enabled racecourse managers to gain and exchange information on the latest developments in research, racecourse development and maintenance, people and resource management, and to learn from overseas experiences and inspection of operations at major race and training tracks. The conference will further racecourse managers’ ability to practise their profession, leading to higher standards of racecourse management with benefits accruing from improvements in track performance, appearance and life, and associated economic and environmental advantages for racing clubs and the community.

Publications 4th Australian Racecourse Managers’ Conference Proceedings,1999

Project Title:

Pasture intake by grazing horses

RIRDC Project No.:

UCS-22A

Researcher: Michael Friend and David Nash Organisation: School of Agriculture

Charles Sturt University PO Box 588 Wagga Wagga NSW 2678

Phone: (02) 6933 4006 Fax: (02) 6933 2812 Email: [email protected]

Objectives • To develop an understanding of the intake of temperate pastures by grazing

weanlings • To assess the ability of pasture species and mixes to meet the nutritional demands of

young growing horses

Background Pastures are considered to be an under-utilised resource in the Australian horse industry. This is often attributed to a lack of confidence by managers in the ability of pastures to meet nutrient requirements. The intake of horses at pasture, along with pasture nutrient levels, will determine whether pastures can meet the nutrient requirements of horses.

Research The pasture intake of weanlings grazing improved (phalaris, annual ryegrass and sub clover) and unimproved (annual ryegrass, silver grass, barley grass and sub clover) pastures at high (1 horse/0.75ha) and low (1 horse/1.25ha) stocking rates was measured using the n-alkane technique. Weanlings used in the study were part of the RIRDC funded project DAV-118A. Digestibility of the selected diet was also estimated using this technique, while intake of energy, protein, macrominerals, iron, zinc, copper and manganese were calculated using data from DAV-118A. Nutrient intake was then compared to National Research Council recommendations for weanlings.

Outcomes Pasture samples collected in May and August 1999 accurately represented what the horses were consuming. However, in November 1998 and October 1999, collected pasture samples did not accurately represent what the horses were consuming. This can lead to errors in intake estimates. Unusually high intake estimates obtained in August and October 1999 are most likely a result of under dosing of C32, and suggests the liquid suspension method of dosing horses requires further development. Weanlings grazing improved pasture at a low stocking rate consumed more pasture overall than those grazing these pastures at a high stocking rate. This difference only occurred in August and November 1999. In contrast, for unimproved pastures intake tended to be greater at the high stocking rate. This trend was observed in November 1998 and October 1999, but was reversed in August 1999. Individual nutrient intakes on both pasture types were sufficient for most nutrients in August and October 1999, but deficient in November 1998 and May 1999.

Project Title

Molecular epidemiology of Rhodococcus equine

RIRDC Project No.:

UM-29A

Researcher: Dr Glenn Browning Organisation: The University of Melbourne

Veterinary Preclinical Centre PARKVILLE VIC 3052


• To determine if there is a relationship between Rhodococcus equi strains

and morbidity and mortality patterns on different studs. • To identify protein(s) which specifically identify virulent strains and to

develop a diagnostic assay based on these protein(s).

Background Rhodococcus equi continues to be a major cause of wastage in foals on Australian Thoroughbred stud farms. Although advances in understanding the ecology of the organism have assisted in developing control strategies based on management, our appreciation of the epidemiology of the disease, and in particular the relationship between different cases, is limited. It is known that the organism multiplies in the environment of horses, particularly in the presence of faeces, but it is probable that only certain environmental strains are virulent. Recent evidence from Japan suggests that virulence is linked to possession of specific groups of genes, although only a limited number of strains have been examined. It is probable that there are specific virulent strains of Rhodococcus equi and that some variation in disease incidence may be due to the dominant strain on a stud. There was clearly a need to clarify the relationship between the organisms which cause different cases of disease to establish whether particular strains are important on any one stud in any one year, and whether particular strains are common to studs with particular patterns of disease. Establishing these relationships is not only important in improving understanding of how the disease may be controlled by management, but is also important for decisions on the appropriate organisms to use for the development of vaccines and diagnostic assays. It is crucial that the most prevalent strains causing disease are used as the basis for any reagents for effective control.

Research

The prevalence of virulence associated genes in isolates of R. equi causing disease in foals was examined and they were found to be present in nearly all of them. The strains of R. equi causing disease were examined and 44 different strains were found. Although particular strains of R. equi were more common on particular farms, there was no evidence that severe disease was associated with particular strains. The strains of R. equi on Australian farms do not appear to be significantly different from those found in a number of countries overseas, including Canada, Germany, Brazil and Japan. Proteins specifically associated with virulent strains were not able to be identified using the methods available at the time of this study, but the publication of the sequence of the virulence plasmid will enable new approaches to be developed.

Outcomes

• The significance of the virulence associated genes in Australian isolates of R. equi was established • A method for comparing strains of R. equi was developed • The distribution of strains on different farms over different years was examined, as well the possibility of any association with specific types of disease • There appears to be no evidence that differences in severity of disease between studs is predominantly due to differences in the strains causing disease

Implications Studies are needed to examine whether particular factors on different studs

increase the relative number of virulent R. equi. Future studies need to examine whether there are suitable vaccine or diagnostic antigens on the virulence plasmid.

Publications

HAITES, R., BEGG, A. P., MUSCATELLO, G., AND BROWNING, G. F. - Prevalence of the virulence associated gene in isolates of Rhodococcus equi from infected foals. Journal of Clinical Microbiology, 35: 1642-1644 (1997) MORTON, A. C., BASEGGIO, N., PETERS, M. A., AND BROWNING, G. F. - Diversity of Isolates of Rhodococcus equi from Australian Thoroughbred Horse Farms. Antonie van Leeuwenhoek 74: 21-25 (1998). BROWNING, G. F. Can Control of Rhodococcus equi be Improved? In Equine Research Seminar 98 Proceedings No. 312, Postgraduate Foundation in Veterinary Science University of Sydney ISBN 1 875582 76 2 pp 91-96 (1998) TAKAI, S., SHODA, M., SASAKI, Y., TSUBAKI, S., FORTIER, G., PRONOST, S., RAHAL, K., BECU, T., BEGG, A. P., BROWNING, G. F., NICHOLSON, V. M., AND PRESCOTT, J. F. - Restriction fragment length polymorphisms of virulence plasmids in Rhodococcus equi. Journal of Clinical Microbiology 37:3417-3420 (1999).

Project Title

Nutrition of grazing broodmares, their foals and young horses

RIRDC Project No.:

UQ-45A

Researcher: Dr Neil McMeniman Organisation: The University of Queensland

School of Veterinary Science ST LUCIA QLD 4072


• To determine the extent to which pastures can support economical

production of quality foals and young horses.

Background At an RIRDC workshop on “Equine Nutrition and Pastures for Horses” in 1995 it was generally accepted that Australian horse production systems based on pastures should be more economical than systems that utilise significant quantities of supplementary feed. However, it was recognised that there was little information available to support this conclusion.

Research

An experiment compared the growth of horses that were set stocked, rotationally grazed and handfed from approximately 6 month to two years of age. The nutrient content of pastures grazed by horses on the experimental site and on commercial studs on the southern Darling Downs and in the Scone area of NSW were determined. The reproductive performance of mares on one commercial stud was recorded over two years.

Outcomes

At the end of the growth experiment the hand fed horses were significantly heavier and had significantly higher condition scores than the horses in the two grazing treatments. However, the skeletal sizes, degree of bone mineralisation and muscle weights were similar in all groups indicating that the hand fed horses were fatter than the grazing horses. A high proportion of the pastures on the experimental site and on the studs had lower than recommended concentrations of calcium, copper and zinc and on some studs sodium concentrations were low. Reproductive performance on the commercial stud was similar that previously reported for other Australian studs.

Implications

The results of the studies show that pastures are capable of supporting satisfactory growth of young horses providing any mineral deficiencies in the pastures are identified and provision made for their supply. In light of these findings horse producers may have more confidence in utilising pastures to a greater extent in their production enterprises.

Publications

McMeniman, N.P. (2000). Nutrition of grazing broodmares, their foals and young horses. Final Report on Project UQ 45A. RIRDC publication No 00/28

Project Title

Assessment and prevention of toxicity from indospicine contaminated horsemeat

RIRDC Project No.:

UQ-46A

Researcher: Dr Michael Pass Organisation: The University of Queensland

Dept of Physiology & Pharmacology ST LUCIA QLD 4072


• To develop a method for detecting indospicine residues in horsemeat that is

suitable for screening large numbers of samples under commercial conditions.

• To develop a definitive system for detection of indospicine residues in horsemeat that can be used under commercial conditions for confirmation and accurate quantitation of indospicine detected by the above screening test.

• To provide information on the mechanism of indospicine toxicity that can be used by the horsemeat industry to counteract threats to our export trade by countries importing horsemeat from Australia.

Background Indospicine is a toxin in the plant Birdsville Indigo. It accumulates in the meat

of horses that eat the plant and when that meat is fed to dogs, some animals develop liver disease. Although the horsemeat industry avoids using horses from regions in with the plant grows, there is still a need for methods to monitor indospicine in export horsemeat destined for human consumption. Development of suitable assays for this purpose was the subject of this research project.

Research

It was identified that High Performance Liquid Chromatography (HPLC) and enzyme linked immunoassay techniques would be the most useful in commercial situations. An HPLC method for measuring indospicine in horsemeat was developed by modification of a commercially available technique. An ELISA method that was specific for detecting indospicine was also developed.

Outcomes

The analytical methods will detect and quantitate indospicine in horsemeat at concentrations as low as 1-2ppm. Based on the information available on the toxicity of indospicine, this level of sensitivity appears to be adequate for commercial application of the assays.

Implications

This research project has developed analytical methods that can be used to access the concentration of the toxin indospicine in meat. Their use for this purpose will ensure that Australian horsemeat is free of indospicine and safe for human consumption.

Publications

Pollitt S, Hegarty MP and Pass MA (2000) Analysis of the amino acid indospicine in biological samples by High Performance Liquid Chromatography, Natural Toxins, In press.

Project Title:

Communication and Information Programs for the Horse Industry

RIRDC Project No.:

US 50A

Researcher: Reuben Rose Organisation: Faculty of Veterinary Science

University of Sydney Sydney, NSW 2006.

Phone: (02) 9351 6935 Fax: (02) 96601548 Email: [email protected] Objectives

• To provide a strong communication program to ensure widespread industry support

for the RIRDC Equine R&D Program and to enable the results of the R&D to be used by the Australian horse industry.

Background In 1996, RIRDC commissioned a survey of Australian horse groups in order to formulate

research priorities for the RIRDC Equine R&D Program. An important outcome of the survey was that communication came across as an important priority. Until the RIRDC Equine R&D Program commenced in 1995, there was no vehicle for communication with the horse industry and no availability of independent research based information.

Research Outcomes

• A database of equine organisations. A database for communication with the

industry • RIRDC Equine Research News. The newsletter of 8 pages, published quarterly,

provides the industry with information on topical research from around the world as well as updates on current RIRDC funded projects, interviews with research workers, workshops and invited reviews.

• RIRDC Internet Web Site. An Internet web site for the RIRDC Horse Program which includes links for online purchase of RIRDC publications, download of the RIRDC Equine Research News, search facility for past issues and a subscription facility to receive the RIRDC Equine Research News via the Internet.

Implications The database contains 920 unique entries, which comprise horse associations, research

institutions and individuals in the Australian horse industry. Since the RIRDC Equine Research News was first published in June 1995, all major horse industry groups have received information about equine research projects that are of interest to the industry groups and also regular updates of research and development projects supported by RIRDC. The Internet web site has provided a way of providing the past and future editions of the newsletter indexed and readily used by researchers, horse organisations, individuals and groups overseas. The web site has received nearly 12,000 hits since it was launched in 1997

Project Title

Biomechanical and biochemcial response of equine superficial flexor tendon to training and injury

RIRDC Project No.:

US-52A

Researcher: Mr Andrew Dart Organisation: The University of Sydney

Rural Veterinary Centre PMB 4, Werombi Road CAMDEN NSW 2570


• To evaluate the changes that occur in the biomechanical and biochemical

properties of normal equine superficial digital flexor tendons in young, previously untrained horses in response to a controlled training program.

• To assess the biomechanical and biochemical properties of injured equine superficial flexor tendons during healing.

Background Superficial digital flexor tendon injury is a major cause of musculoskeletal injury

affecting up to 30 % of horses in race training. Healing of SDFT injuries tends to be slow, with re-injury common. It has been reported that only approximately 20-60 % of affected horses may successfully return to racing with up to 80 % of horses sustaining re-injury. Recent investigations in tendon pathology have found age and exercise related changes to occur in equine tendons. These degenerative alterations may predispose the tendon to injury. The mechanisms of age related changes in musculoskeletal tissue composition and mechanical behaviour are diverse and complex. However, the role of declining circulating concentrations of various growth factors has been incriminated.

Research

Three experiments were performed examining the in vitro biomechanical properties of the metacarpal region of forelimb equine superficial digital flexor tendons. Experiment 1 was aimed at determining the in vitro biomechanical properties of forelimb SDFT from horses without evidence of clinical tendonitis. Experiment 2 examined the effect of equine recombinant somatotropin (eST) on the in vitro biomechanical properties of normal tendons. Experiment 3 examined the effect of eST administration on the in vitro biomechanical properties of healing tendons.

Outcomes

Despite the problems associated with in vitro biomechanical testing, the methodology was shown to be repeatable, and, to provide objective data on the biomechanical properties of tendons in response to various treatments. The lack of detectable effect of eST on the biomechanical properties of normal, mature SDFT may be related to a number of factors. The equine SDFT has been shown to reach maturity at approximately 2 to 3 years of age. It is possible that mature tendons have a reduced capacity to respond to an eST stimulus given the cellular changes that are apparent with maturity and within the metacarpal region of SDFT. In addition previous exercise history and eST dose rate may have influenced biomechanical response of the tendons. Further investigations into tendon responses to eST at different dose regimens, in immature animals, and under controlled exercise programs may be indicated. The biomechanical results support diminished structural properties in the eST treated healing tendons. This may be due, in part, to an immature or biomechanically inferior, disorganized collagenous matrix. Future histological

and immuno-histochemical analysis will help to determine the exact effect of eST on collagen synthesis and ultrastructural organisation.

Implications Despite the apparently negative findings of this study, the pharmacological basis behind the use of eST in healing of collagenous tissue injuries, including tendonitis is relatively sound. Further investigations may be warranted using the described techniques, however a longer treatment period prior to biomechanical testing may yield more favourable results.

Project Title

Respiratory ventilation and tracheal sounds in horses with airway disease

RIRDC Project No.:

US-53A

Researcher: Dr David Evans Organisation: The University of Sydney

Department of Animal Science SYDNEY NSW 2006


• To investigate the use of two techniques for field studies of airway

function during and/or after exercise of moderate intensity.

Background The performance of athletic horses is frequently compromised by respiratory disease. There are few techniques for pulmonary function testing of horses that accurately describe lung function, and enable informed decisions concerning therapy. Likewise, there are few techniques that enable measurement of the responses to treatments of equine respiratory disease.

Research

The experiment conducted in this project involved measurement of tracheal sounds and breath by breath airflow during and after treadmill exercise in normal horses, and in horses with a model of upper airway obstruction. As well, tracheal sounds were successfully recorded during field exercise in Thoroughbred racehorses.

Outcomes

A new method of measuring pulmonary function in Australian performance horses has been successfully evaluated. As well, the feasibility of field studies of pulmonary function in galloping Thoroughbred horses has been determined.

Implications

The results of the investigations in this project have immediate implications for evaluation of horses with respiratory disease. The methods will now be adapted for use in further studies of cases of upper airway obstruction and other respiratory diseases in athletic horses in the University of Sydney Equine Performance Laboratory.

Project Title

Training and Fitness in Athletic Horses

RIRDC Project No.:

US-77A

Researcher: Dr David Evans Organisation: The University of Sydney



• The objective of this project is technology transfer, or the transfer of

information to industry participants. A book will be written which will serve as a reference for those in the horse training industry. The book will colate the results of research on horse training and fitness assessment, and present the information in a format suitable for industry participants.

Background Over the last 40 years there has been much research on the exercise physiology

of equine athletes, including racehorses, event horses and endurance horses. However, the results of this research have not been comprehensively assembled in a format that is accessible to most industry participants. Many new industry participants have more formal education in equine science, and there is an increased interest in the applications of research results in the horse training industries.

Research

A literature search was conducted in order to assemble and organise the latest knowledge concerning the science of horse training and fitness evaluation.

Outcomes

The scientific bases of training and fitness assessment are described. The topics cover training of Thoroughbred, Standardbred, event, endurance and other athletic horses. Use of heart rate and blood lactate measurements for fitness assessment and monitoring training are described, and methods of conducting fitness tests on treadmills and in the field are covered.

Implications

Presentation of the science of horse training and fitness assessment in a language and format suitable for horse trainers and owners should increase industry knowledge of recent research findings. Where possible, the implications of the research findings for practical horse training and management are described. Adoption of new techniques in training, fitness assessment, and techniques for routine monitoring of horses in training will contribute to all equine athletic industries. The research results provide practical guidelines concerning ways to increase fitness and reduce ill health and wastage rates in athletic horses.

Project Title

How well are we meeting the training needs of the horse industry? (Workshop)

RIRDC Project No.:

US-81A

Researcher: Philip Pogson Organisation: The University of Sydney

School of Veterinary Science SYDNEY NSW 2006

Phone: (02) 9809 5185 / 0412 459156 Fax: (02) 9809 5185 Objectives

• To identify the major issues and problems in the education, training and

development of horse industry workers. • To identify what currently appears to be working/effective in such

education, training and development. • To agree on what areas are currently not being covered/ are not working

effectively. • To canvas the question of what could be done at a national level to

improve, rationalise and coordinate education, training and development in the horse industry in the future.

• To begin to set a national agenda to operationalise 1-4 above. • To produce a comprehensive document resulting from the workshop which

incorporates the information and ideas for networking which supported the workshop processes

Background Education, training, learning and knowledge management are highly important

for the future of the equine industry in Australia. However, up to this point, the delivery of effective education and training has been somewhat disjointed and uncoordinated. This Workshop was premised on the need to create a national agenda for horse industry training and education so as to fully realise the potential benefit quality education and training services can offer.

Research

Participants engaged in a broad range of activities including the presentation of papers, panel discussions, formal exercises, and informal networking over the three days of the Workshop. Conference participants committed themselves to improving these issues through the various Action Groups, and to communicate important matters of concern to their local, State and National industry bodies. The RIRDC will support the activities of the Action Groups and continue to work towards improving research and development throughout the Australian Horse Industry.

Outcomes Six major Action Areas emerged. Action Group 1: Training, Updating and Assessing Educators Action Group 2: Education for Juniors Action Group 3: Training Packages Action Group 4: Horse Employer Awareness Action Group 5: Australian Horse Industry Council Action Group 6: Improving industry-wide learning

Implications

Not all the areas of concern identified were directly to do with training and education. Learning was also seen as being of crucial importance, as were marketing, industry structure and governance, cooperation and collaboration within the industry, and Government lobbying. It was also pointed out to participants that the RIRDC Equine R & D program itself is not as firmly established as it should be and is still funded by a voluntary levy.

Publications

Supporting Learning in the Horse Industry: Are we meeting industry needs?

Project Title

Diagnosis of and protection against infections caused by Rhodococcus equine

RIRDC Project No.:

USA-6A

Researcher: Dr Mary Barton Organisation: University of South Australia

School of Pharmacy and Medical Sciences GPO Box 2471 ADELAIDE SA 5001


• To develop an accurate, reproducible and easily performed serological test

for early diagnosis of R.equi infections in foals. • To identify antigenic epitopes that may be further investigated as potential

vaccines to protect foals from infection.

Background Rhodococcus (Corynebacterium) equi is an important cause of pneumonia (“rattles”) and death in young foals. At present there is no effective diagnostic test that enables early diagnosis and hence early treatment. Furthermore, there is no effective vaccine to help prevent the disease.

Research

A sensitive and specific blood test has been developed which need to be more fully evaluated in the field. A novel vaccine has been developed which is currently being tested in a mouse model.

Outcomes

Work do date suggests that we should be able to develop an effective blood test for early diagnosis of infection in foals. The efficacy of the vaccine remains to be evaluated.

Implications

The blood test and the vaccine are the subjects of patent applications and will be developed further.

3.5 Horses

Research in Progress Project Title

Health and performance of pony club horses (Stage 1)

RIRDC Project No.:

UCS-24A

Start Date: 7/05/99 Finish Date: 1/02/00 Researcher: Dr. Petra Ecke Organisation: Charles Sturt University

Riverina Campus PO Box 588 WAGGA WAGGA NSW 2678

Phone: (02) 6933 2426 Fax: (02) 6933 2812 Email: [email protected] Objectives

• Stage 1 • To explore the perceptions of horse health and performance (H&P) amongst

pony club members. These perceptions will be collected using a qualitative method of inquiry (semi-structured interviews).

• To gain an understanding of issues relating to horse H&P, that are important to the Wagga Wagga PC community.

Current Progress

Stage 1 has been successfully completed and has provided valuable insights into H&P issues of importance to PC members. Thirty-two interviews were conducted, taped and transcribed for analysis. Questions asked started with a ‘what’ or ‘how’ to encourage elaboration. When a relevant topic emerged during an interview, the investigator continued this lead, eg ‘you mentioned your horse misbehaved, can you elaborate?’ However, leading questions or closed questions were avoided. Issues of importance were identified as topics that recurred in different interviews. These included (not in any particular order) nutrition, teeth care, foot care, deworming, colic, laminitis, sore backs, horse behaviour and skin disease (Brisbane). As a result of stage 1, we are now able to improve our study design for stage 2 to specifically target pony club horses and their owners. In addition to meeting our stage 1 objectives, the investigators have achieved an important rapport with members of pony club. This rapport has established a sense of trust & ownership among participants in the research process. This is expected to support any recommended change of practice at the end of subsequent stage 3.

Project Title

Epidemiology of equine rhinovirus type 2 (ERhV2)

RIRDC Project No.:

UM-40A

Start Date: 6/07/98 Finish Date: 30/07/00 Researcher: Dr. Carol Hartley

Prof. Michael Studdert Organisation: The University of Melbourne

Centre for Equine Virology Dept of Veterinary Science PARKVILLE VIC 3052


• To determine the epidemiology of ERhV2 in Australian horses. • To design diagnostic tests for ERhV2 based on polymerase chain reaction

(PCR) and enzyme linked immunosorbent assay (ELISA). • To investigate the potential of an ERhV2 vaccine based on recombinant

baculovirus expressed virus-like particles.

Current Progress

In order to gain some understanding of the sero-epidemiology of ERhV2 infections in the Australian horse population, virus neutralisation assays were performed (>300). The data from this study provides one of the first indications that ERhV2 is present and circulating amongst the Australian horse population. The results indicate that horses less than one year of age are generally sero-negative (5% of sera tested with serum neutralisation titre of ≥ 80), sero-positive horses tend to cluster in 2 to 4 year old age range (52% of sera tested with serum neutralisation titre of ≥ 80). ERhV2-specific primers have been designed to the 3A and 3D regions of the genome in order to develop PCR assays which could be used as a diagnostic assay to detect ERhV2 in clinical material. The primers designed to both the 3A and 3D region are able to detect a range of different ERhV2 isolates, but neither primer pair are able to detect the 29 different ERhV2 isolates available in our laboratory. The 3D region of several ERhV2 isolates are currently being sequenced in order to design primers capable of detecting all ERhV2 isolates. To investigate the potential of an ERhV2 vaccine based on recombinant baculovirus expressed virus-like particles, we have cloned the genome encoding the structural proteins of ERhV2 into a baculovirus vector. Trials will soon begin to express these structural proteins in insect cells and evaluate their potential as antigens for use in both a diagnostic ELISA, and a vaccine.

Project Title

Effects of stud management on ecology of virulent Rhodococcus equi

RIRDC Project No.:

UM-47A

Start Date: 1/01/00 Finish Date: 31/12/02 Researcher: Dr. Glenn Browning Organisation: The University of Melbourne

Veterinary Preclinical Centre PARKVILLE VIC 3052


• Improve understanding of the ecology of virulent strains of Rhodococcus

equi • Identify factors in horse studs which may result in increased amounts of

virulent R. equi in the air inhaled by foals • Develop management strategies for reducing the airborne population of R

equi, thus reducing both the amount and severity of rattles and leading to improved responses to treatment

Current Progress

We have appointed Dr Gary Muscatello as a postgraduate student to work on this project. He has now assessed the potential of the different selective culture media for use in air sampling work and has developed a probe for the virulent strains of the bacteria. His current focus is on standardising the assay in preparation for initial studies on horse studs in Spring this year.

Project Title

Improved vaccine strategies for management of equine herpesvirus diseases

RIRDC Project No.:

UMA-15A

Start Date: 1/07/98 Finish Date: 30/06/01 Researcher: A/Prof. Millar Whalley Organisation: Macquarie University

School of Biological Sciences SYDNEY NSW 2109


• Improvement of reproductive efficiency and respiratory health in horse

populations through reduction of incidence of herpesvirus abortion and respiratory infection.

• Improved preventative strategies against infectious dieases of the horse, and lower costs.

• Possible establishment of generic vaccine technology applicable to different diseases affecting horses.

Current Progress

One component of this project is to monitor the incidence and prevalence of equine herpesviruses 1 and 4 (EHV-1 and EHV-4) in mares and foals in stud farms in New South Wales. We showed previously that EHV-1 infects in early life with a peak incidence of infection in 90-day old foals, and a follow-up study is in progress on 40 mares and their foals from birth. In ongoing research into responses to vaccination and the effect of vaccination on the epidemiology of EHV-1, results of a cross-sectional survey of EHV-1 antibody in vaccinated mares and their unvaccinated foals are being compared with 1995 data from an unvaccinated population. The project aims also to assess the potential of new vaccines for EHV-1 (and EHV-4), based on recombinant envelope proteins. As part of this research, we have investigated the ability of direct DNA inoculation to induce immune responses in horses. Intramuscular inoculation of DNA expressing an EHV-1 envelope protein led to increased EHV-1-specific antibody in 9 of 15 adult horses with pre-existing antibody. We believe that these responses can be further enhanced by boosting with recombinant protein. The responses to DNA vaccination are currently being tested also in a group of foals.

Project Title

Analysis of horse breeding efficiency in Australia

RIRDC Project No.:

UMO-26A

Start Date: 20/07/99 Finish Date: 31/07/02 Researcher: Dr. Angus McKinnon Organisation: Goulburn Valley Equine Hospital

PO Box 2020 SHEPPARTON VIC 3630


• Analysis of breeding record via the Stud Books. This is only expected to

provide an overview of industry practices. For a variety of reasons, records submitted to the Stud Book (both racing codes) are only a superficial view of breeding practices, however they do represent the true and relevant fertility's of the different breeds and even different stallions on the same breeding farms.

• Analysis of individual mare records from selected breeding farms. • This is an ambitious attempt to collate data from a wide variety of sources. • It is estimated that 30,000 individual mare records of each breed from a

variety of studs that have been chosen to represent three levels of management will be used to compare factors such as fertility per cycle, effect of fuid pre and post service, effect of scanning or not, rate and time period of early embrionic death, etc. Provisional data will be obtained from our own breeding records, (we have 3000 already analysed and 4000 to put on the database

Current Progress

The project began by enlisting the help of world renowned epidemiologist Dr Dave Dargatz and Colleagues from the National Animal Health Monitoring System (NAHMS) in the USA. Because we are looking at many variables and there relationships we have spent many hours organizing the best way to handle huge amounts of data. We currently are analyzing our first data sets (breeding records from around 2000 mares). The results of the first analysis will be used to plan the next phase (breeding records from around Australia).

Project Title

Identification of infectious respiratory disease in horses as a basis for better management of cases

RIRDC Project No.:

UMU-22A

Start Date: 1/07/97 Finish Date: 30/06/00 Researcher: A/Prof. Graham Wilcox Organisation: Murdoch University

School of Veterinary Studies MURDOCH WA 6150


• To investigate the association between viruses and respiratory disease in

horses in Western Australia by (a) clinically defining respiratory conditions of unknown or suspected viral aetiology and (b) examining the association between viruses and each of these clinical conditions.

• To multiple sample affected horses to determine the effect of the stage of the disease process and site of sampling on the ability to detect viruses associated with each clinical condition.

Current Progress

A study of the association between viruses and respiratory disease in horses has been completed. Viral respiratory infection was confirmed in a relatively small proportion of horses presented for evaluation of respiratory disease. Utilising conventional virus isolation techniques in combination with a multiplex PCR for the detection of viruses, active viral infection of the respiratory tract was identified in only 24% of a study population of 84 horses: 9 horses had EHV1, 10 had EHV4 and one had EHV1&4. Horses with active viral disease could be discriminated by evaluation of history and physical examination, and in the 20 horses from which virus was isolated, a correct clinical diagnosis of viral respiratory disease was made for 16 (80%). Virus isolation was negative for a large proportion of horses that were believed to have viral respiratory disease on clinical presentation, suggesting that non-viral problems, such as lower airway disease, were a significant cause of respiratory disease in the study population. Sequential nasal swab and peripheral blood samples were collected from foals and yearlings. These samples demonstrated a high prevalence of apparently latent viral infection. Infection with EHV5 was particularly common, although concurrent infection with other herpes viruses was also observed. Evidence was found for an association between EHV2 infection and respiratory disease in weanlings.

Project Title

Investigation into radiographic changes in the carpus (C3) in racehorses

RIRDC Project No.:

UMU-24A

Start Date: 20/07/99 Finish Date: 30/11/01 Researcher: Dr. Catherine Steel Organisation: Murdoch University

Murdoch University Veterinary Clinic Murdoch Drive MURDOCH WA 6150


• Describe radiographic changes in the third carpal bone (C3) in a large group

of racehorses during their 1st year of training using a system of interpretation of radiographs that can be readily applied by veterinarians in practice.

• Correlate radiographic findings with clinical findings in order to determine the clinical significance of various radiographic changes in C3, and to determine radiographic changes that may predict the onset of carpal lameness due to C3 sclerosis, chip fracture, slab fracture and osteoarthritis of the carpus, which often result in wastage due to lost training time or retirement.

• To determine the influence of training and rest on the progression and/or resolution of radiographic changes so that recommendations can be made to trainers and owners regarding the management of horses with clinically significant C3 sclerosis and the prevention of carpal lameness.

Current Progress

Methods for ensuring radiographic film quality and consistency and for describing changes in C3 on skyline radiographic view of the carpus have been developed. Sixty four Standardbred horses were examined for lameness and radiographed at approximately 3 monthly intervals during their 1st year of training. Fifty horses reached at least the trialing stage of training and of these, 18 horses (18/50, 36%) were lame in 1 or both forelimbs at the time of examination. The lameness was localised to the intercarpal joint(s) using intra-articular local anaesthesia in 14 horses (14/18, 78%). Third carpal bone sclerosis was the only radiographic change in these horses. The C3 was confirmed to be the site of lameness using nuclear scintigraphy in all 3 horses in which it was performed. Sclerosis tended to increase with training, commencing in the radial facet, however, it was observed in 16% horses at the start of training. When present early in training, it is usually associated with lameness or effusion of the intercarpal joint. Correlation between total area and severity of sclerosis and degree of lameness have not yet been made. With rest, and resolution of lameness, the scintigraphic images returned to normal in the 1 horse in which they were obtained, however, radiographic images retained a moderate degree of sclerosis. In preparation for the 2nd year of the study, a further 40 yearling Standardbreds have been examined and radiographed before commencing training.

Project Title

Safe and effective grain feeding for horses

RIRDC Project No.:

UNE-62A

Start Date: 1/01/98 Finish Date: 30/06/00 Researcher: Prof. James Rowe Organisation: University of New England

ARMIDALE NSW 2351 Phone: (02) 6773 2225 Fax: (02) 6773 3275 Email: [email protected] Objectives

• To reduce the risk and incidence of foot problems, related to laminitis and

connected with feeding cereal grain, through understanding which grains are most likely to cause problems and which methods of feed treatment are most effective in reducing these risks.

Current Progress

During the last 12 months the project has examined 2 grains that offer significant potential to the horse industry: low lignin oats and triticale. These grains were identified using in vitro assays measuring potential intestinal digestion and fermentation characteristics during the first part of the project. • In the case of oats the use of low lignin oats produced approximately six

digestibility points more digestibile energy than high lignin oats. • Studies with triticale indicate that it produces less accumulation of acid

within the gut than when similar amounts of oats or barley are fed. • Measurements on particle size suggest that very fine grinding is essential

if sorghum is to be fed to horses. • Research in progress is designed to investigate cultivars of triticale that

appear to have different intestinal digestibility and the potential benefits of using exogenous enzymes with wheat grain for horses.

Project Title

Novel anti-inflammatory drugs to treat inflammatory diseases in horses

RIRDC Project No.:

UQ-71A

Start Date: 1/09/98 Finish Date: 1/09/01 Researcher: Dr. Stephen Taylor Organisation: The University of Queensland

Dept of Physiology and Pharmacology BRISBANE QLD 4072


• To test novel classes of anti-inflammatory drugs that will reduce the impact

of inflammatory diseases of the lung, eye and joint on the normal structure of affected tissues in horses. By reducing fibrosis, oedema, cellular hyperplasia and changes in the phenotype of resident cells, the long term impact of inflammatory diseases, like pneumonia, arthritis and uveitis, on performance and well being will be reduced.

Current Progress

Intestinal pathology in horses is a significant clinical problem and is frequently manifest as colic. Reperfusion of ischaemic bowel leads to a worsening of the intestinal damage caused by the primary insult (e.g. strangulation, embolism). Surgical intervention to correct the cause of the colic has been shown to be associated with a high mortality. If the blood supply is interrupted for a considerable time necosis results and the only course of action is to surgically remove the permanently damaged segment. If, however, the blood supply is reestablished before irreparable damage occurs, a further insult results from reoxygenation of the tissue due to the formation of oxygen-derived free radicals (OFR). The consequences of reperfusion injury to the gut, muscle etc is both local and global within the body. The liberation of soluble mediators from the reperfused tissue can cause changes in other organ systems leading to multisystem organ failure (MSOF). This is frequently seen in the lung. We have developed an in vivo assay of intestinal reperfusion injury that incorporates elements of MSOF in which to test new phospholipase inhibitors. The results to date indicate the usefulness of this class of drugs for this purpose.

Project Title

Nutritent intake and growth of young horses

RIRDC Project No.:

UQ-72A

Start Date: 1/07/98 Finish Date: 30/06/01 Researcher: Dr. Neil McMeniman Organisation: The University of Queensland



• To determine whether weanling horses grazing lush spring pastures can

suffer a check in growth and whether this check is due to the fact that the high soluble carbohydrate containing diets contain insufficient fibre. The consequences in terms of subsequent growth and skeletal development to a check in growth will be determined.

• The project will also provide information on the effect of pasture maturity and yield on intake and growth of young horses.

• Information on which pasture species young horses prefer to consume will also be obtained.

Current Progress

To date three paddock experiments have been completed within this project. Results for the second and third of these experiments have not yet been finalised. In the first experiment three paddocks containing lucerne and pitted blue grass were used. A group of 6 yearlings then grazed the separate paddocks 7, 22 and 35 days after being slashed. Synthetic alkane markers were used to determine faecal output and then further determine dry matter (DM) intake, DM digestibility and botanical composition of the diets consumed. Pasture heights and yields were ≤11cm and 399 kg DM/ha for 7 regrowth, 23 cm and 3063 kg DM/ha for 22 day regrowth and 47 cm and 3557 kg DM/ha for 35 day regrowth, respectively. Significant differences were noted in the dry matter intake and dry matter digestibility over the 3 grazing periods. As the age of the pasture increased there was an increase in yield, a decrease in dry matter digestibility and an initial decrease in dry matter intake. However, in the third grazing period, when the pasture was at its most mature stage, intake was not further depressed even though dry matter digestibility was reduced. Additional experiments will further investigate these relationships.

Project Title

Repeatability and reliability of Brochoalveolar Lavage (BAL) in the horse

RIRDC Project No.:

UQ-73A

Start Date: 1 June 1998 Finish Date: 31 August 2000 Researcher: Dr John Thornton & Ms Joanne Hamilton Organisation: The University of Queensland

Division of Companion Animal Clinical Sciences School of Veterinary Science ST LUCIA QLD 4072


• To evaluate the reliability and repeatability of the Bronchoalveolar Lavage

(BAL) technique in the horse to allow its refinement and improved interpretation under Australian conditions

Current Progress

In completing this comprehensive evaluation of the BAL technique we used 12 horses to examine the volume of fluid instilled, the frequency of instillations and the use of inflated and uninflated cuffed BAL tubes. The horses remained healthy throughout the experimental period with little sign of respiratory or other disease. There were no difficulties experienced with the use of either the Bivona or Cook BAL catheters and fluid instillation and withdrawal was generally without incident. Laboratory work still to be completed includes some final reporting on the histological examination of the lungs and the completion of differential cell counts from the lavage fluids. These should be completed within the next month to allow completion of the final report

Project Title

The pathogenesis and prevention of equine laminitis

RIRDC Project No.:

UQ-75A

Start Date: 1/07/98 Finish Date: 30/06/02 Researcher: Dr. Christopher Pollitt Organisation: The University of Queensland



• To determine the role and control the activity of matrix metalloproteinases

in the pathogenesis of laminitis so that a product can be developed which will prevent and treat the disease.

• To determine the role of changes in the pattern of glucose metabolism in the pathogenesis of laminitis as a basis for predicting and preventing laminitis.

Current Progress

The pathological mechanism that causes the pedal bone to separate from the inner hoof wall is now better understood. The gene controlling production of matrix metalloproteinase (MMP-2), the enzyme that normally controls growth and remodelling of the continually growing hoof wall, is dramatically upregulated when laminitis first appears. The primary substrate of MMP is the basement membrane, a thin sheet of connective tissue the binds the hoof to the connective tissue of the pedal bone. Loss and separation of the lamellar basement membrane, caused by uncontrolled MMP activation, causes the hoof and pedal bone to come apart. Using our in vitro laminitis model we have shown that a toxin produced by hindgut Streptococcal bacteria activates hoof lamellar MMP thus mimicking the natural lesion of laminitis. When horses consume excess grain or lush grass the microflora of the hindgut become unbalanced and a population explosion of anaerobic Streps occurs. The toxin they produce escapes into the circulation and activates the hoof MMP enzymes to cause laminitis. The testing of several preventive strategies, based on these discoveries, (eg MMP enzyme inhibition, Strep exotoxin neutralisation and foot circulation manipulatiion) is currently underway.

Project Title

A Longitudinal Cohort Study of Inflammatory Airway Disease in Racing Thoroughbreds

RIRDC Project No.:

US-82A

Start Date: 26/07/99 Finish Date: 31/07/00 Researcher: Dr. Jennifer Hodgson Organisation: The University of Sydney

University Veterinary Centre Camden Department of Veterinary Clinical Sciences PMB 4, Narellan Delivery Centre NARELLAN NSW 2567


• To identify the risk factors associated with development of inflammatory

airway disease (IAD) in young racing thoroughbreds. Studies will investigate the presence of pollutants and aero-allergens in racing stables and their association with development of IAD in a number of different stable management conditions. The role of viral and bacterial infections in IAD and their interplay with pollutants/aero-allergens will also be studied

Current Progress

Recent extensive collaboration with researchers from the UK and Australia has resulted in a refined and better organised project plan without changing the original objectives or hypotheses. This study will now incorporate longitudinal and case-control epidemiological methods to determine the incidence of, and non-infectious risk factors for, IAD in 2-3 year old racehorses. Collection of management and environmental data as well as tracheal wash and blood samples from appropriately selected 2-3 year old racehorses from racehorse trainers in the Sydney Metropolitan region is well underway. In addition, a preliminary study examining the effects of stable bedding and feeding on respirable dust endotoxin concentration has been performed. Investigations into aeroallergens and development and validation of the Allergen Particle Immuno-staining assay is underway although progress is still being hampered by the unavailability of an equine anti-IgE assay. A number of different options for obtaining this reagent are currently being investigated

Project Title

An epidemiological study of risk factors for shin soreness in Thoroughbred racehorses

RIRDC Project No.:

US-84A

Start Date: 2/01/00 Finish Date: 31/07/03 Researcher: Dr. David Evans Organisation: The University of Sydney



• The objective of this project is to undertake an epidemiological study of the

risk factors for shin soreness in Thoroughbred horses. A better understanding of the risk factors will facilitate design of superior training and managment strategies for Thoroughbred horses, and a reduction in wastage due to shin soreness

Current Progress

In January 2000 Ms Naomi Cogger (BSc(Hons)) was appointed as the PhD student for this project. The project commenced with interviews to obtain feedback from horse trainers and veterinarians concerning aspects of the design of the study. The study’s commencement has been widely publicised in the industry. An article has been published in NSW Racing Magazine with the generous support of the Thoroughbred Racing Board, and letters have been sent to numerous national and state industry stakeholders. Ms Cogger has been recruiting trainers in the Sydney region, and there has been a high level of support for the study by trainers. This support reflects widespread concern about the impact of shin soreness on the training and racing of young thoroughbred racehorses, and the high level of wastage attributable to the disease. Equine veterinarians in Sydney have also offered generous assistance and support, and wherever possible the study will take place in conjunction with veterinarians at each stable. Draft survey forms covering aspects of enrolling training stables and individual horses, and horse activity records, have been written. These instruments will be tested in a pilot study over April and May 2000. Design of the database has also commenced.

Project Title

Assessment and prevention of toxicity from indospicine-contaminated horsemeat

RIRDC Project No.:

USU-1A

Start Date: 26/07/99 Finish Date: 30/11/00 Researcher: Dr. Michael Pass Organisation: University of the Sunshine Coast

Faculty of Science Locked Bag No. 4 MAROOCHYDORE DC QLD 4558


• To provide information on the mechanism of indospicine toxicity that can

be used by the horsemeat industry to develop arguments to counteract threats to our export trade from countries importing horsemeat from Australia.

Current Progress

Indospicine is a plant toxin that occurs in Indigofera linnaei (Birdsville Indigo). Indospicine accumulates in the meat of horses that consume the plant and is known to cause liver disease in dogs that eat the contaminated horsemeat. The toxicity for people is unknown and the horsemeat industry actively avoids sourcing animals from regions in which the plant grows. Nevertheless, inadvertent inclusion of contaminated meat in shipments destined for human consumption is possible and it is therefore important to know if human intoxication is possible. This project is aimed at determining the mechanisms that make individual animals susceptible to poisoning and thus provide a basis for predicting human toxicity. Indospicine is an analogue of arginine. Similar analogues have been shown to induce liver disease by inhibiting the synthesis of nitric oxide from arginine. Our previous work has shown that indospicine inhibits nitric oxide synthesis which led to us to propose that differences in the concentration of the enzyme responsible for nitric oxide synthesis, nitric oxide synthase (NOS), may be related to susceptibility to indospicine toxicity. This is being tested in the current project. A method for measuring NOS in tissues has been developed and this is being used to compare NOS activity in liver from species that are susceptible to that in species that are not susceptible to poisoning.

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