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Effects of water exchange regimes on growth, s

Aquacult Int (2006) 14:587–594
DOI 10.1007/s10499-006-9057-y
ORIGINAL PAPER

Effects of water exchange regimes on growth, survival
and shell normality of the hatchery reared juvenile
spotted babylon (Babylonia areolata Link 1807)
in a recirculating seawater system
S. Kritsanapuntu Æ N. Chaitanawisuti Æ
W. Santhaweesuk Æ S. Y. Natsukari
Received: 23 August 2005 / Accepted: 17 May 2006 /
Published online: 14 July 2006
Ó Springer Science+Business Media B.V. 2006

Abstract Growth, survival and shell normality of hatchery reared juvenile
Babylonia areolata were examined at four water exchange regimes of 0, 15, 30 and
60 day intervals in a recirculating seawater system over a 120 day experimental
period. Higher body weight gains and shell length increments were observed in
snails held at water exchange of 15 day intervals, especially when compared with
those held at water exchange of 60 and 0 day intervals (P < 0.05). Water exchange
affected the final survival of B. areolata. At the end of the experiment, final survival rates were 65.47 ± 0.66%, 87.48 ± 0.67%, 86.34 ± 0.92% and 78.50 ± 3.26%

for snails held in the water exchange treatments of 0, 15, 30, and 60 day intervals,
respectively, and those of shell abnormality were 97.65 ± 1.04%, 93.09 ± 2.34%,
97.08 ± 1.18% and 96.71 ± 1.84%, respectively. The present study concluded that
water exchange regimes of the recirculating system influenced growth, survival,
shell normality and water quality of the recirculating culture system for this
species.
Keywords Babylonia areolata Æ Recirculating seawater system Æ Water exchange
regime Æ Growth Æ Survival

S. Kritsanapuntu
Faculty of Technology and Management, Prince of Songkla University (Surat Thani campus),
Surat Thani, Thailand
e-mail: kanutr@hotmail.com
N. Chaitanawisuti (&) Æ W. Santhaweesuk
Aquatic Resources Research institute, Chulalongkorn University, Pathumwan,
Bangkok, Thailand
e-mail: nilnajc1@hotmail.com
S. Y. Natsukari
Faculty of Fisheries, Nagasaki University, Nagasaki, Japan

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Aquacult Int (2006) 14:587–594

Introduction
From an aquaculture point of view, the spotted babylon, B. areolata, had many
biological attributes, production, and market characteristics necessary for a profitable
aquaculture venture, and it was considered a promising new candidate of aquaculture
species for the land-based aquaculture industry in Thailand. Growing public demand
and expanding markets for spotted babylon for a healthy, tasty, and affordable food is
stimulating the ‘‘boom’’ in this industry. A catastrophic decline in wild spotted
babylon populations as a result of overharvesting promoted the culture of
farms—spotted babylon grown in indoor systems (Chaitanawisuti et al. 2002a, b).
Although large-scale rearing of B. areolata in Thailand was technically feasible using
flow-through and static seawater systems in concrete/canvass ponds, the disadvantages of these systems were: they generally require large quantities of water; location
of production systems must be near the sea; stock was vulnerable to external water
supply and quality problems; growth rate was significantly influenced by water flow
(Chaitanawisuti and Kritsanapuntu 1999). Recirculating systems were mechanically
sophisticated and biologically complex and had been used for growing fish and
shellfish for more than three decades. Interest in recirculating systems is due to their
perceived advantages, which include: greatly reduced land and water requirements;
high degree of environmental control allowing productive-cycle growth at optimum
rates; the feasibility of locating areas far from the sea; and a major issue of water
conservation and reuse (Losordo et al. 1998; Masser et al. 1999; Lazur and Britt
1997). Research on recirculating systems may offer an alternative to pond aquaculture technology. It provides major leaps in the intensification and technology of the
culture of spotted babylon. Much of this progress is necessary to maximize profits by
increasing production, lowering costs, and conserving water. However, there is a lack
of studies on growing of juvenile spotted babylon to marketable sizes in recirculating
systems in Thailand. The goal of the present studies was to determine the effects of
water exchange regimes on growth, survival and shell normality of hatchery reared
juvenile spotted babylon, B. areolata, in a recirculating seawater system.

Materials and methods
Experimental animals
Juvenile spotted babylons used in growth and survival experiments were produced
from a private hatchery. Individuals from the same cohort were sorted by size to
prevent possible growth retardation of small spotted babylons when cultured with
larger ones. Initial shell length and whole-body weight of the spotted babylon averaged 1.06 ± 0.16 cm and 0.33 ± 0.02 g, respectively, and did not differ significantly
among treatments [P > 0.05, analysis of variance (ANOVA)]. Juveniles were raised
in tanks as described below at densities of 300 individuals m–2 or 250 snails per tank.
Experimental culture systems
Each 50 l plastic culture tank was an independent recirculating system with air lift
pump and a biological filter tank. The bottom area of the culture tank was 0.78 m2.
The biological filter tank of 20 l capacity contained shell fragments and gravel as

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