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International Journal of Marine Science 2013, Vol.3, No.40, 319-332
http://ijms.sophiapublisher.com
319
Research Article Open Access
Low-input Modified Extensive Shrimp Culture Systems for Penaeus monodon
Restrain Vibriosis
Sheryl Oliveira Fernandes1, R.A. Sreepada 2, Shantanu S. Kulkarni2, Sheetal V. Karekar2, Resha R. Shirodkar2,
Christian Vogelsang3, P. A. LokaBharathi1
1. Marine microbiology laboratory, CSIR-National Institute of Oceanography, Dona Paula, Goa - 403 004, India
2. Aquaculture laboratory, CSIR-National Institute of Oceanography, Dona Paula, Goa - 403004, India
3. Norwegian Institute for Water Research (NIVA), Brekkeveien 19, Kjelsaas-N-0411 Oslo, Norway
Corresponding author email: loka@nio.org
International Journal of Marine Science, 2013, Vol.3, No.40 doi: 10.5376/ijms.2013.03.0040
Received: 13 Jun., 2013
Accepted: 16 Jul., 2013
Published: 17 Aug., 2013
Copyright © 2013 Fernandes et al., This is an open access article published under the terms of the Creative Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Preferred citation for this article:
Fernandes et al., 2013, Low-input Modified Extensive Shrimp Culture Systems for Penaeus monodon Restrain Vibriosis, International Journal of Marine
Science, Vol.3, No.40 319-332 (doi: 10.5376/ijms.2013.03.0040)
Abstract It was hypothesized that an outbreak of vibriosis can be restrained in ponds with a low stocking density (~5 post-larvae m-2) till
harvest. Therefore, during a 135 day production cycle of Penaeus monodon at an aquaculture facility, we monitored (i)
physico-chemical parameters (ii) abundance of total heterotrophic bacteria (THB), total Vibrio like organisms (TVLO) and
luminescent bacteria (LB) (iii) alterations in environmental factors controlling Vibrio abundance and (iv) changes in composition of
the Vibrio community. Physico-chemical parameters were within the optimum range recommended for culture of P. monodon . In
source and pond water, THB abundance remained steady at 103 CFU mL-1 throughout the culture period whereas in sediments, they
varied between 102-4 CFU g-1. The abundance of TVLO and LB in pond components were below the threshold levels of 104 CFU
mL-1 and 102 CFU mL-1 respectively. THB, TVLO and LB were more abundant in the shrimp hepatopancreas (105 CFU g-1) yet
apparently below the threshold for the outbreak of vibriosis in the current set up. Changes in bacterial abundance were seemingly
independent of changes in environmental parameters suggesting that the systems maintained TVLO below disease-causing threshold.
The Vibrio community was represented mainly by V. metschnikovii, V. fluvialis, V. mimicus and the closely related Aeromonas spp.
The vibrios in shrimp hepatopancreas were similar to other pond components with no dominance of particular species. A disease-free
environment prevailed and shrimp yield was sustainable within the set framework perhaps due to the low abundance of vibrios
represented by innocuous strains.
Keywords Abundance; Bacteria; Environmental conditions; Species diversity; Shrimp culture; Vibriosis
Introduction
In the recent years aquaculture has emerged as the
world’s fastest food-producing sector growing at an
annual rate of almost 10% per year since 1970
(Subasinghe, 2005). Shrimp farming constitutes an
important source of revenue and employment in many
developing countries in Asia and Latin America.
However, rapid expansion of this industry has
spawned various technical, ecological, economical
and social ordeals. A multitude of factors has
contributed to the health problems currently faced by
the industry. Between 1987 and 1994, the combined
economic losses from shrimp diseases in 11 countries
were estimated at US $ 3019 million. In India, the loss
during 1994 was estimated at US $ 125 million
(Israngkura and Sae-Hae, 2002). Therefore, the
sustainability of shrimp culture industry largely
depends on disease control and health status of the
shrimp. Outbreaks of vibriosis and low survival rates
in hatchery and grow-out ponds (Lightner, 1988;
Lightner, 1993; Brock and Lightner, 1990) have
become a severe barrier to the development of shrimp
aquaculture. Vibrios are among the most abundant
cultivable microbes in aquatic environments
(Heidelberg et al., 2002) and usually constitute a part
of normal micro flora in farmed and wild penaeid
shrimps. Opportunistic vibrios may turn pathogenic
when shrimps are stressed due to deteriorated
environmental conditions like sub-optimal or unstable
environment, high stocking densities and inadequate
management. When such stresses prevail, a large
increase in the number and composition of Vibrio spp.
in the culture environment is expected (Sung et al.,
1999). Despite the opportunistic nature of most