RIRDC Publication No 04/006

The views expressed and the conclusions reached in this publication are those of the authors 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 unless authorised in writing by the Managing Director of RIRDC. This publication is copyright. Apart from any fair dealing for the purposes of research, study, criticism or review as permitted under the Copyright Act 1968, no part may be reproduced in any form, stored in a retrieval system or transmitted without the prior written permission from the Rural Industries Research and Development Corporation. Requests and inquiries concerning reproduction should be directed to the Managing Director