Viability of white spot syndrome virus (WSSV) in shrimp pond sediments with reference to physicochemical properties
- 47 Downloads
The white spot syndrome virus (WSSV), the causative agent of white spot disease (WSD) of shrimp, has emerged as a single most critical pathogen causing severe epizootics, inflicting significant economic loss to the global shrimp aquaculture industry. It can be transmitted vertically from infected broodstock to post-larvae and horizontally by cannibalism, invertebrate carriers, water, and sediment. Shrimp pond sediment represents an important reservoir of WSSV. The viability of WSSV in sediment is the most vital parameter in the transmission of WSD in the freshly stocked ponds. The physicochemical properties of sediment influence the viability and infectivity of WSSV. The objective of this study was to determine the viability of WSSV with reference to the physicochemical properties of pond sediment under farm conditions. The viability of WSSV in sediment samples from three WSSV-affected ponds with different soil types was examined using polymerase chain reaction (PCR), quantitative PCR, and infectivity studies. The soil characteristics, such as texture, pH, organic carbon (OC), electrical conductivity (EC), and moisture content were examined to unravel their relationship with the viability of WSSV. The WSSV could be detected in these shrimp pond sediments by PCR up to 35 to 52 days. However, it was revealed that the WSSV was infective up to 21 and 32 days in sandy clay loamy soil and 25 days in sandy loamy soil, suggesting the infectivity of WSSV was prolonged in sandy clay loamy soil. Further, the viability of WSSV was found to be dependent on the moisture content of the pond sediment and independent of organic carbon, pH, and electrical conductivity. These observations reinforce the adoption of best management practices (BMPs) like sun-drying of ponds for at least 3–5 weeks between the crops to achieve biosecurity and ensure successful culture.
KeywordsSediment physico-chemical characteristics WSSV infectivity WSSV viability PCR Shrimp WSSV
Authors sincerely thank the shrimp farmers from Tamil Nadu and Andhra Pradesh for providing the samples for this study.
S.S.K. and R.A.B. collected the samples, carried out the infectivity studies, and analyzed the samples by PCR. J.J.S. carried out the real-time PCR analysis. M.M. planned the relevant environmental parameters of this study. V.C. analyzed the environmental parameters. S.V.A., S.S.K., and J.J.S. wrote the manuscript. All the authors contributed to the analysis and interpretation of the results. S.V.A. conceived, planned, and coordinated the study.
The authors are thankful to the Department of Biotechnology, Govt. of India, New Delhi, for the financial support for this research work (BT/PR 12833/AAQ/03/484/2009 dated 29th June 2010).
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
All applicable institutional guidelines for the care and use of animals were followed by the authors.
- Armanious A, Aeppli M, Jacak R, Refardt D, Sigstam T (2016) Viruses at solid–water interfaces: a systematic assessment of interactions driving adsorption. Environ Sci Technol 50:732–743Google Scholar
- Bitton G (1980) Introduction to environmental virology. John Wiley and Sons, New YorkGoogle Scholar
- Fauquet CM, Mayo MA, Maniloff J, Desselberger U, Ball LA (2005) Virus taxonomy: VIII report of the International Committee on Taxonomy of Viruses. Academic Press, LondonGoogle Scholar
- Gerba CP (1983) Virus survival and transport in groundwater. Dev Ind Microbiol 24:247–251Google Scholar
- Gerba CP (2005) Survival of viruses in the marine environment. In oceans and health: pathogens in the marine environment. Springer, Boston MA, pp 133–142Google Scholar
- Gerba CP, Bitton G (1984) Microbial pollutants: their survival and transport pattern to groundwater. In: Bitton G, Gerba CP (eds) Groundwater pollution microbiology. John Wiley and Sons, Inc., New York, pp 65–68Google Scholar
- Hurst CH, Gerba CP, Cech I (1980) Effects of environmental variables and soil characteristics on virus survival in soil. Appl Environ Microbiol 40:1067–1079Google Scholar
- Jackson ML (1973) Soil chemical analysis. Prentice Hall, Englewood Cliffs 452 pGoogle Scholar
- LaBelle RL, Gerba CP (1980) Influence of estuarine sediment on virus survival under field conditions. Appl Environ Microbiol 39:749–755Google Scholar
- OIE (2012) White spot disease. Manual of diagnostic tests for aquatic animals. http://www.oie.int/fileadmin/Home/eng/Healthstandards/aahm/2010/2.2.06,WSD.pdf. Accessed 12 March 2013
- Piper CS (1966) Soil and plant analysis. Hans Publishers, BombayGoogle Scholar
- Prescott JA, Taylor JK and Marshall TJ, (1934) The relationship between the mechanical composition of the soil and the estimate of texture in the field. Transactions 1st commission, International Society of Soil Science pp. 143–153Google Scholar
- Ritchey EL, McGrath JM, Gehring D (2015) Determining soil texture by feel. Agriculture and Natural Resources Publications, p 139. https://uknowledge.uky.edu/anr_reports/139
- Satheesh Kumar S, Ananda Bharathi R, Rajan JJS, Alavandi SV, Poornima M, Balasubramanian CP, Ponniah AG (2013) Viability of white spot syndrome virus (WSSV) in sediment during sun-drying (drainable pond) and under non-drainable pond conditions indicated by infectivity to shrimp. Aquaculture 402-403:119–126CrossRefGoogle Scholar
- Yeager JG, O'Brien RT (1979) Structural changes associated with poliovirus inactivation in soil. Appl Environ Microbiol 38:702–709Google Scholar