238
J. Nabhitabhata
of domesticated cultured broodstocks for hatchling production at a certain degree.
However, there would be an unknown and unavoidable risk that culture through
several (more than three) generations could result in some inbreeding effects. Therefore, it would be better to obtain additional broodstocks from different populations
(cultured or wild) in order to avoid a potential decrease of growth due to inbreeding.
From an aquaculture-for-restocking point of view, this matter should be considered
in order to maintain a gene pool and genetic variation of natural populations.
The small final size turns out to be the advantage, being required by the seafood
industry for frozen food product processing and packaging as well as live cuttlefish
products that can also be distributed to the ornamental aquaculture trade, in a similar manner to S� pharaonis (see Chap. 12, this volume).
The main focus of future research is the developing of feed, both live and artificial, for large-scale culture. However, the feasibility is at a higher level due to
the active habit compared to S� pharaonis. The acceptability of the enrichment of
Artemia sp. (Muthuwan et al. 1993) as supplementary and substitute feed for young
cuttlefish in the nursing phase is a promising trend for the solution of the bottleneck
during the nursing phase.
The differences in growth rate probably also depend on the environmental history
of the broodstocks between estuarine and open sea populations. Early maturation,
a smaller final size and a shorter lifespan tend to occur in the estuarine population
due to the effects caused by the diversity of environmental fluctuations in estuaries.
The source for the collection of wild broodstocks has to be known in order to have
a proper management. Nabhitabhata and Polkhan (1983b) reported that the young
S� inermis, offspring of estuarine broodstocks in Thailand, grew faster with a higher
survival in salinity of 28 psu than in 32 psu which is the normal salinity of open waters. The young also demonstrated their preference for the mud substrate to a similar
degree to the sand substrate, in contrast to the obvious preference for sand by S�
pharaonis (Nabhitabhata and Polkhan 1983a; Nabhitabhata and Nilaphat 2000). In
view of maximising the aquaculture production, the differences in the growth rate
and reproductive products among different populations should be identified and
studied in detail to determine whether it is the result of the plasticity of life cycles
in different habitats or the genetic difference. Reid et al. (2005) suggested that S�
inermis is possibly a species complex. Overall, this species has good adaptability to
culture conditions that makes them easy to culture.
13.8 Conclusions
Culture process of S� inermis is comparable to that of other sepiid cuttlefish, which
comprises a collection of broodstocks from the wild, incubation of egg masses,
nursing of the young in the hatchery and growout phase. Egg masses and hatchlings
are nursed in concrete tanks. Water quality is partially controlled in open seawater
systems. The short period of planktonic habit of hatchling requires a directed water
flow in nursing tanks. Density is area oriented due to benthic habit. Initial density
J. Nabhitabhata
of domesticated cultured broodstocks for hatchling production at a certain degree.
However, there would be an unknown and unavoidable risk that culture through
several (more than three) generations could result in some inbreeding effects. Therefore, it would be better to obtain additional broodstocks from different populations
(cultured or wild) in order to avoid a potential decrease of growth due to inbreeding.
From an aquaculture-for-restocking point of view, this matter should be considered
in order to maintain a gene pool and genetic variation of natural populations.
The small final size turns out to be the advantage, being required by the seafood
industry for frozen food product processing and packaging as well as live cuttlefish
products that can also be distributed to the ornamental aquaculture trade, in a similar manner to S� pharaonis (see Chap. 12, this volume).
The main focus of future research is the developing of feed, both live and artificial, for large-scale culture. However, the feasibility is at a higher level due to
the active habit compared to S� pharaonis. The acceptability of the enrichment of
Artemia sp. (Muthuwan et al. 1993) as supplementary and substitute feed for young
cuttlefish in the nursing phase is a promising trend for the solution of the bottleneck
during the nursing phase.
The differences in growth rate probably also depend on the environmental history
of the broodstocks between estuarine and open sea populations. Early maturation,
a smaller final size and a shorter lifespan tend to occur in the estuarine population
due to the effects caused by the diversity of environmental fluctuations in estuaries.
The source for the collection of wild broodstocks has to be known in order to have
a proper management. Nabhitabhata and Polkhan (1983b) reported that the young
S� inermis, offspring of estuarine broodstocks in Thailand, grew faster with a higher
survival in salinity of 28 psu than in 32 psu which is the normal salinity of open waters. The young also demonstrated their preference for the mud substrate to a similar
degree to the sand substrate, in contrast to the obvious preference for sand by S�
pharaonis (Nabhitabhata and Polkhan 1983a; Nabhitabhata and Nilaphat 2000). In
view of maximising the aquaculture production, the differences in the growth rate
and reproductive products among different populations should be identified and
studied in detail to determine whether it is the result of the plasticity of life cycles
in different habitats or the genetic difference. Reid et al. (2005) suggested that S�
inermis is possibly a species complex. Overall, this species has good adaptability to
culture conditions that makes them easy to culture.
13.8 Conclusions
Culture process of S� inermis is comparable to that of other sepiid cuttlefish, which
comprises a collection of broodstocks from the wild, incubation of egg masses,
nursing of the young in the hatchery and growout phase. Egg masses and hatchlings
are nursed in concrete tanks. Water quality is partially controlled in open seawater
systems. The short period of planktonic habit of hatchling requires a directed water
flow in nursing tanks. Density is area oriented due to benthic habit. Initial density