Channel Catfish Virus Disease.Pdf
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Diseases of finfish Viral diseases—Channel catfish virus disease exotic Signs of disease exotic Important: animals with disease may show one or more of the signs below, but disease may still be present in the absence of any signs. Disease signs at the farm level exotic • high mortality in fry and juvenile catfish Disease signs at the tank and pond level • mortality exotic Clinical signs of disease in an infected animal CCVD-affected channel catfish fingerling. Note swollen • ascites (swollen abdomen from accumulated stomach and ‘pop eye’ exotic fluid) Source: L Hanson • exophthalmus (pop eye) • haemorrhaging of fins Gross signs of disease in an infected animal exotic • haemorrhaging of muscle • extensive necrosis of renal tubules and interstitial tissues of the kidney exotic Disease agent Channel catfish virus disease (CCVD) is caused by a herpesvirus (Ictalurid herpesvirus 1) exotic Host range Fish known to be susceptible to CCVD: blue catfish* (Ictaluris furcatus) exotic channel catfish* (Ictaluris punctatus) white catfish (Ictaluris catus) exotic * naturally susceptible (other species have been shown to be experimentally susceptible) exotic Sourced from AGDAFF–NACA (2007) Aquatic Animal Diseases Significant to Asia-Pacific: Identification Field Guide. Australian Government Department of Agriculture, Fisheries and Forestry. Canberra. © Commonwealth of Australia 2007 This work is copyright. It may be reproduced in whole or in part subject to the inclusion of an acknowledgment of the source and no commercial usage or sale. PAGE 1 Channel catfish virus disease continued exotic Presence in Asia–Pacific exotic EXOTIC — has not been officially reported in the Asia–Pacific region under the NACA–FAO–OIE quarterly aquatic animal disease reporting program. Epidemiology exotic • Horizontal transmission occurs directly from virus shed in water, and from virus carried by animate vectors and on fomites. • Vertical transmission is believed to be common. However, because no infectious virus has been found on the skin or sexual products at spawning, this mechanism has not been proven. • Survivors of CCVD remain covert carriers of the virus. exotic • Susceptibility appears to vary according to the strain of channel catfish. • Although older fish are susceptible to outbreaks of the CCVD, the disease occurs almost exclusively in fish that are less than one year old, and generally in fish less than four months old. exotic • Mortality is highest where water temperature exceeds 27°C, but decreases with temperature and ceases at 18°C. Differential diagnosis exotic The differential diagnostic table and the list of similar diseases appearing at the bottom of each disease page refer only to the diseases covered by this field guide. Gross signs observed might well be representative of a wider range of diseases not included here. Therefore, these diagnostic aids should not be read as a guide to a definitive diagnosis, but rather as a tool to help identify the listed diseases that most closely account for the gross signs. exotic Similar diseases Enteric septicaemia of catfish Sample collection exotic Because of uncertainty in differentiating diseases using only gross signs, and because some aquatic animal disease agents might pose a risk to humans, you should not try to collect samples unless you have been trained. Instead, you should phone your national hotline number and report your observations. If exotic samples have to be collected, the agency taking the call will advise you on what you need to do. Local or district fisheries/veterinary authorities could advise you on sampling. Emergency disease hotline For your national emergency disease hotline number, see Whom to contact if you suspect a disease. exotic exotic Sourced from AGDAFF–NACA (2007) Aquatic Animal Diseases Significant to Asia-Pacific: Identification Field Guide. Australian Government Department of Agriculture, Fisheries and Forestry. Canberra. © Commonwealth of Australia 2007 This work is copyright. It may be reproduced in whole or in part subject to the inclusion of an acknowledgment of the source and no commercial usage or sale. PAGE 2 exotic exotic exotic exotic exotic exotic exotic exotic exotic exotic exotic PAGE 3 PAGE inclusion of an CCVD are summarised at publication. Aquatic Animal Diseases Significant to Asia-Pacific: Identification Asia-Pacific: Animal Diseases Significant to Aquatic m © Commonwealth of Australia 2007 © Commonwealth of acknowledgment of the source and no commercial usage or sale. Australian Government Department of Agriculture, Fisheries and Forestry. Canberra. Fisheries and Forestry. Agriculture, Australian Government Department of . Field Guide This work is copyright. It may be reproduced in whole or in part subject to the This work is copyright. Sourced from AGDAFF–NACA (2007) Sourced from These hyperlinks were correct and functioning at the time of The currently accepted procedures for a conclusive diagnosis of http://www.oie.int/eng/normes/fmanual/A_00023.ht Further reading http://www.oie.int/aac/eng/cards/en_diseasecard.htm Channel catfish virus disease continued.