Virus diseases risk-factors associated with shrimp farming practices in rice-shrimp and intensive culture systems in Mekong Delta Viet Nam

In Mekong Delta, viral infection, including white spot syndrome virus (WSSV), monodon baculovirus (MBV), heptopancreatic parvovirus (HPV), infectious hypodermal and hematopoietic necrosis virus (IHHNV) and gill-associated nidovirus (GAV) frequently infect cultured shrimp starting at the postlarvae stage. These viral infections cause high mortality of shrimp and affect the farmer’s income. Previous studies mainly focused on the detection, transmission and genetic variation of the pathogens, but few studied the correlation between disease occurrence and other factors, including pond conditions, culture technique and management. Three studies analysed the association of culture factors with the WSSV disease incidence determining risk and potential protective factors in freshwater rice-shrimp systems, and brackish water polyculture and monoculture of black tiger shrimp (Penaeus monodon). Studies on the risk and protective factors in the odd of viral diseases in rice-shrimp rotation were lacking, while in 2011 the Early Mortality Syndrome (EMS)/Acute Hepatopancreatic Necrosis Syndrome (AHPNS) caused the great losses of cultured shrimp in Mekong Delta. This study was carried out to describe the culture status of shrimp in Mekong Delta and to identify the risk and/or protective factors that related to disease incidences in black tiger shrimp cultured in 2011. Through interviews, 58 variables collected from 191 farmers (64: rice-shrimp rotation and 127: intensive system) in Soc Trang and Bac Lieu Provinces, Viet Nam. The data were analysed in two steps of variable reduction to increase model stability and binary logistic regression to identify the risk and/or protective factors. The results showed that the risk factors were pond size (entire dataset, rice-shrimp rotation and intensive culture), settling pond (entire dataset), period of pond dry (entire dataset), stocking density first (rice-shrimp rotation), and stocking density second (rice-shrimp rotation). The potential protective factors were the mode of water intake (entire dataset), water level (entire dataset and rice-shrimp rotation), water quality parameters before stocking (entire dataset), and fry test (rice-shrimp rotation).

[1]  D. Smith,et al.  Effect of arachidonic acid supplementation on reproductive performance of tank‐domesticated Penaeus monodon , 2011 .

[2]  C. Dimmock,et al.  Gill-associated nidovirus of Penaeus monodon prawns transcribes 3'-coterminal subgenomic mRNAs that do not possess 5'-leader sequences. , 2002, The Journal of general virology.

[3]  K. Morgan,et al.  Risk factors associated with white spot syndrome virus infection in a Vietnamese rice-shrimp farming system. , 2001, Diseases of aquatic organisms.

[4]  S. Shiau,et al.  Choline requirements of grass shrimp (Penaeus monodon) as affected by dietary lipid level , 2002 .

[5]  Jie Huang,et al.  White spot syndrome virus (WSSV) detected by PCR in rotifers and rotifer resting eggs from shrimp pond sediments. , 2004, Diseases of aquatic organisms.

[6]  J. Chakraborti,et al.  Seasonal incidence of protozoan parasites of the black tiger shrimp (Penaeus monodon) of Sundarbans, West Bengal, India , 2011, Journal of parasitic diseases : official organ of the Indian Society for Parasitology.

[7]  A. Yakupitiyage,et al.  Production and economic efficiencies of intensive black tiger prawn (Penaeus monodon) culture during different cropping seasons in the Mekong delta, Vietnam , 2011, Aquaculture International.

[8]  Y. Mgaya,et al.  Abundance and Reproductive Biology of the Penaeid Prawns of Bagamoyo Coastal Waters, Tanzania , 2004 .

[9]  R. Lester,et al.  Diseases of cultured prawns in Australia , 1989 .

[10]  M. Phillips,et al.  Farm-level plans and husbandry measures for aquatic animal disease emergencies. , 2008, Revue scientifique et technique.

[11]  Helena Clayton,et al.  Rice-shrimp farming in the Mekong Delta: biophysical and socioeconomic issues , 2003 .

[12]  C. Lo,et al.  The Transition from Pre-patent to Patent Infection of White Spot Syndrome Virus (WSSV) in Penaeus monodon Triggered by Pereiopod Excision , 1998 .

[13]  P. Soundarapandian,et al.  Effect of Different Stocking Densities on the MBV Infected Seeds of Black Tiger Shrimp, Penaeus monodon (Fabricius) , 2010 .

[14]  J. R. Arthur,et al.  Disease and health management in Asian aquaculture. , 2005, Veterinary parasitology.

[15]  G. Giorgetti.  Disease problems in farmed penaeids in Italy , 1989 .

[16]  J. E. Vickers,et al.  A non-occluded, systemic baculovirus that occurs in cells of ectodermal and mesodermal origin and causes high mortality in the black tiger prawn Penaeus monodon. , 1995 .

[17]  D. Oanh,et al.  Prevalence of White Spot Syndrome Virus ( WSSV ) and Monodon Baculovirus ( MBV ) Infection in Penaeus monodon Postlarvae in Vietnam , 2005 .

[18]  M. M. Babu,et al.  Factors Determining Spawning Success in Penaeus monodon Fabricius , 2001 .

[19]  K. C. George,et al.  Histopathological survey of cultured shrimps in Cochin, Kerala , 2003 .

[20]  P. K. Bandyopadhyay,et al.  First record of a parasitic septate gregarines (Apicomplexa: Sporozoea) in the shrimp Peneaus monodon in Sundarbans of West Bengal , 2010, Journal of parasitic diseases : official organ of the Indian Society for Parasitology.

[21]  A. Tassanakajon,et al.  Antimicrobial peptides from the black tiger shrimp Penaeus monodon – a review , 2012 .

[22]  K. Hatai,et al.  Fusarium incarnatum isolated from black tiger shrimp, Penaeus monodon Fabricius, with black gill disease cultured in Vietnam. , 2004, Journal of fish diseases.

[23]  R. Hoffmann,et al.  Experimental transmission of white spot syndrome virus (WSSV) from black tiger shrimp Penaeus monodon to the sand crab Portunus pelagicus, mud crab Scylla serrata and krill Acetes sp. , 1998 .

[24]  K. M. Shankar,et al.  Evaluation of immune response and resistance to diseases in tiger shrimp, Penaeus monodon fed with biofilm of Vibrio alginolyticus. , 2010, Fish & shellfish immunology.

[25]  Houng-Yung Chen,et al.  Nutritional Requirements of the Black Tiger Shrimp: Penaeus monodon , 1998 .

[26]  T. Flegel,et al.  Presence of multiple viruses in non-diseased, cultivated shrimp at harvest , 2004 .

[27]  I. Liao,et al.  A brief review of nutritional studies for Penaeus monodon , 1989 .

[28]  B. Withyachumnarnkul,et al.  Multiple pathogens found in growth-retarded black tiger shrimp Penaeus monodon cultivated in Thailand. , 2004, Diseases of aquatic organisms.

[29]  K. Sritunyalucksana.  Characterisation of Some Immune Genes in the Black Tiger Shrimp, Penaeus Monodon , 2001 .

[30]  J. Vlak,et al.  Molecular epidemiology of white spot syndrome virus within Vietnam. , 2004, The Journal of general virology.

[31]  C. Dimmock,et al.  Gill-associated virus of Penaeus monodon prawns: an invertebrate virus with ORF1a and ORF1b genes related to arteri- and coronaviruses. , 2000, The Journal of general virology.