Fish Health Better Management Practices for Murray Cod farming. (Version 1.0) Brett Ingram, Geoff Gooley, Tracey Bradley, Huiking Ho, Shari Cohen August 2012 Fisheries Victoria Technical Report Series 76 Murray Cod Fish Health BMP If you would like to receive this Printed by DPI Queenscliff, Victoria information/publication in an Published by the Department of Primary accessible format (such as large Industries. print or audio) please call the Copies are available from the website: Customer Service Centre on: www.dpi.vic.gov.au/fishing 136 186, TTY: 1800 122 969, General disclaimer This publication may be of assistance to you but or email the State of Victoria and its employees do not [email protected] guarantee that the publication is without flaw of any kind or is wholly appropriate for your Copyright © The State of Victoria, Department of particular purposes and therefore disclaims all Primary Industries, 2012. liability for any error, loss or other consequence which may arise from you relying on any This publication is copyright. No part may be information in this publication reproduced by any process except in accordance with the provisions of the Copyright Act 1968. The information contained in this publication is for general information only. The State of Preferred way to cite: Victoria does not expressly or impliedly Ingram B, Gooley G, Bradley T, Ho H, Cohen S guarantee that the proposed chemical treatments (2012). Fish health better management practices contained within this publication will be wholly for Murray cod farming. Version 1.0. Fisheries appropriate for your situation. The proposed Victoria Technical Report No. 76. Department of chemical treatments are drawn from a range of Primary Industries, Queenscliff, Victoria, sources, including common farming practices Australia. 60 pp. and are not intended to be a substitute for ISSN 1835‐4785 professional veterinary advice. The appropriateness of the proposed chemical ISBN 978‐1‐74326‐262‐7 (Print) treatments will depend on the circumstances in Author Contact Details: which they are intended to be used. It is Brett Ingram recommended that you seek professional Fisheries Research Branch, Fisheries Victoria veterinary advice before adopting and PO Box 114, Queenscliff Victoria 3225 implementing any chemical treatment options for managing fish health in Murray Cod. Authorised by the Victorian Government, 2a Bellarine Hwy, Queenscliff, Victoria 3225 Murray Cod Fish Health BMP ii Executive Summary The Murray cod aquaculture industry has been developing slowly across the eastern states of Australia in recent years. This iconic, threatened fish has excellent aquaculture prospects and small quantities are already sold into domestic markets. The production of fingerlings for stock enhancement purposes has been established commercially since the 1980s. More recently a range of different culture techniques have been established for growout including cages in ponds and free ranging in pond systems. These systems are particularly well suited to horticultural enterprises with large water holdings as a means of adding value to a valuable water resource. Previous work has established that, like all aquaculture species, there are a range of health conditions affecting Murray cod that can result in loss of income in culture systems. Anecdotally it appears that parasites in particular pose a threat to the healthy production of Murray cod in open systems. However more work needs to be undertaken in the documentation and rigorous identification of these disease threats. The purpose of this “Better Management Practices” manual is to provide farmers with a practical and evolving resource that can assist them in addressing the myriad of health problems that can affect Murray cod, including disease agents and environmental factors. This manual is supported by a series of Standard Operating Procedures and Appendices that cover a diverse range of subjects. Where this BMP does provide information on available chemical treatments for common parasites, diseases and conditions that affect the health of Murray cod in aquaculture, those treatments are drawn from a range of sources, including common farming practices, and are not intended to be a substitute for professional veterinary advice. It is recommended that professional veterinary advice is sought before adopting and implementing any chemical treatment options for managing fish health in Murray cod. Murray Cod Fish Health BMP iii Table of Contents Executive Summary............................................................................................. iii Introduction............................................................................................................ 1 Fish health and aquaculture ....................................................................................................................................1 Murray cod aquaculture ...........................................................................................................................................1 Better management practices...................................................................................................................................2 Standard Operating Procedures..............................................................................................................................2 Objectives of this BMP.............................................................................................................................................2 Murray cod aquaculture industry ...................................................................... 4 Industry overview......................................................................................................................................................4 Hatchery Phase........................................................................................................................................................4 Nursery Phase .........................................................................................................................................................5 Grow‐out Phase.......................................................................................................................................................5 Markets.....................................................................................................................................................................5 Murray cod industry health survey........................................................................................................................5 Common health problems in farmed Murray cod.......................................... 7 Infectious diseases and parasites............................................................................................................................7 Sources of infectious diseases and parasites .......................................................................................................7 Protozoan parasites....................................................................................................................................................7 1. Chilodonella ...........................................................................................................................................................7 2. Ichthyophthirius multifiliis, (Ich or whitespot) ..................................................................................................9 3. Trichodina..............................................................................................................................................................9 4. Tetrahymena..........................................................................................................................................................9 5. Ichthyobodo necator (Costia necatrix) ...................................................................................................................9 Other protozoan parasites .....................................................................................................................................9 Copepod parasites ...................................................................................................................................................12 1. Lernaea spp (anchor worm)..............................................................................................................................12 2. Ergasilid copepods ...........................................................................................................................................12 Fungi ..........................................................................................................................................................................13 1. Aphanomyces invadans .......................................................................................................................................13 2. Saprolegniosis......................................................................................................................................................13 Viruses .......................................................................................................................................................................15 1. Megalocytivirus...................................................................................................................................................15 Bacteria...................................................................................................................................................................15