The ink is an important issue to be dealt with in their captive maintenance, because they can increase grey colouration and can foul gills13. Nabhitabhata and Nilaphat14 provided sand and gravel to assist the animal in burrowing while no substrate was provided in the present study. The animals did not show a change in their behaviour though there was an absence of substrate.
Rectangular tanks were easy to maintain as in the present experiment. But Boletzky and Hanlon5 stated that round tanks eliminate areas of stagnant circulation and corner crowding while Oestmann et al.,13 have mentioned that the circular tanks are not space efficient. The rectangular tanks solve both the problems because there was no corner crowding and the space was sufficient enough for the culture. If irritated, the cuttlefish shoot backwards by jet propulsion and can eject ink shortly after hatching15. This can result in fin damage as they hit against the wall of the culture tanks. Some of the Paralarvae that hatched out from the wild spawned eggs were released after 10 days of culture from the lab to the sea. They did not exhibit any aggregating behaviour when released in the sea but preferred to be isolated from each other as explained by Hanlon and Messenger16and this confirms with the earlier findings that cuttlefishes prefer a solitary life.
A major limitation in culturing larger number of cephalopods has been providing the proper nutrition. Live feeds are expensive because of the time and equipment required as well as personnel to collect and maintain them17. This problem was not faced in the present study except for the time spent by the lab personnel to collect the mysids from the nearby mangrove area. For a larger scale culture, supply of live feed becomes very difficult unless and until there is a hatchery nearby. There are few reports on
Table 4—Growth rate of Sepia pharaonis paralarvae fed with Artemia and mysis feed
ARTEMIA FEED MYSIS FEED
Day DML Length Day DML Length
(mm) (mm)
% Increase % Increase
0 6 -- -- 0 6 -- --
10 8.8 3.78 2.8 10 8.1 3.5 2.1
20 9.96 2.48 1.16 20 10.9 3.5 2.8
non-living and/or non-marine food items being fed to the cephalopods in captivity, but these alternative foods were usually added as supplements to the normal diet with only qualitative observations on acceptance and growth18. Flesh of fish was accepted while the flesh of crabs was refused in the present study (Table 4). Survival was poor with crabs and no qualified growth data have been published so far18. Zooplankton was also prescribed as feed for Loligo opalescens19. However the inability to grow any cephalopod species on a storable, inexpensive diet has inhibited commercial cephalopod mariculture20.
From the reports of the culture from Thailand for the same species, the size of the hatchlings was 7.7 mm in DML and weighed 0.18 g while in the present study; the same species measured only 6 mm and weighed 0.0985 g. There is a marked difference for the same species from two different regions. The Paralarva of the same species from two different areas showed difference in the body weight and DML (7 mm DML and 0.9 g weight in average for the species from Andaman Sea) as stated by14. This is clear evidence that the size, hatching rate and survival depends on the geographical distribution of Sepia pharaonis and also the parent stock. Graphs 1 and 2 explains the difference between the culture results of present study and in Thailand. At 130 days culture period, the length of animals where to be almost same (84 mm for the present study and 84.1 mm for the Thai culture in average). The weight and length increase for the Thailand culture is higher when compared to the present culture. The Thai researchers had provided a mixture of live feed for the Paralarvae like post larvae of shrimps and mysids. The small size of the animals in the present study may be due to the difference in the nutritional value of the feed provided. Many workers have provided alternate diets to the mysids and brine shrimp like Gambusia sp. or other viviparous freshwater fishes18. All these experiments purely depend on the area they are being
846 INDIAN J MAR.SCI., VOL. 40, NO. 6, DECEMBER 2011
culture and the type of live feed available. The overall view of this experimental culture clearly indicates that a simple Closed Circulation System (CCS) is sufficient to raise the Pharaoh’s cuttlefish. Though mass rearing is possible, for a commercial basis, the escalating costs of live feed have to be taken uder consideration before venturing.
หมึกเป็นปัญหาสำคัญจะได้รับการจัดการในการบำรุงรักษาของพวกเขาถูกคุมขัง เนื่องจากพวกเขาสามารถเพิ่ม colouration สีเทา และสามารถสุขภาพ gills13 Nabhitabhata และ Nilaphat14 ที่มีทรายและกรวดเพื่อช่วยสัตว์ในรูในขณะที่พื้นผิวไม่ได้รับในการศึกษาปัจจุบัน สัตว์ไม่ได้แสดงการเปลี่ยนแปลงในพฤติกรรมของตนว่ามีการขาดงานของพื้นผิวรถถังสี่เหลี่ยมได้ง่ายต่อการรักษาเช่นในการทดลองอยู่ แต่ Boletzky และ Hanlon5 ระบุว่า รอบถังกำจัดไหลเวียนนิ่งและมุมสมาชิกขณะ Oestmann et al. 13 ได้กล่าวถึงว่า ถังวงกลมไม่ใช่พื้นที่อย่างมีประสิทธิภาพ ถังสี่เหลี่ยมแก้ปัญหาทั้งสองเนื่องจากมีมุมไม่เบียดเสียด และพื้นที่เพียงพอพอที่วัฒนธรรม ถ้าระคายเคือง ปลาหมึกการถ่ายย้อนหลัง โดยการพ่น และสามารถเลื่อนหมึกหลัง hatching15 นี้สามารถทำความเสียหายของครีบ ตามที่พวกเขาตีกับผนังของถังวัฒนธรรม บางส่วนของ Paralarvae ที่ฟักออกจากไข่สร้างป่าถูกนำออกใช้หลังจากวันที่ 10 ของวัฒนธรรมจากห้องปฏิบัติการไปทะเล พวกเขาไม่ได้แสดงการรวมพฤติกรรมเมื่อออกทะเล แต่ต้องการจะแยกจากกันตามที่อธิบายไว้ โดย Hanlon และ Messenger16and นี้ยืนยัน ด้วยผลการวิจัยก่อนหน้านี้ว่า cuttlefishes ชอบชีวิตโดดเดี่ยวA major limitation in culturing larger number of cephalopods has been providing the proper nutrition. Live feeds are expensive because of the time and equipment required as well as personnel to collect and maintain them17. This problem was not faced in the present study except for the time spent by the lab personnel to collect the mysids from the nearby mangrove area. For a larger scale culture, supply of live feed becomes very difficult unless and until there is a hatchery nearby. There are few reports on Table 4—Growth rate of Sepia pharaonis paralarvae fed with Artemia and mysis feed ARTEMIA FEED MYSIS FEED Day DML Length Day DML Length (mm) (mm) % Increase % Increase 0 6 -- -- 0 6 -- -- 10 8.8 3.78 2.8 10 8.1 3.5 2.1 20 9.96 2.48 1.16 20 10.9 3.5 2.8 non-living and/or non-marine food items being fed to the cephalopods in captivity, but these alternative foods were usually added as supplements to the normal diet with only qualitative observations on acceptance and growth18. Flesh of fish was accepted while the flesh of crabs was refused in the present study (Table 4). Survival was poor with crabs and no qualified growth data have been published so far18. Zooplankton was also prescribed as feed for Loligo opalescens19. However the inability to grow any cephalopod species on a storable, inexpensive diet has inhibited commercial cephalopod mariculture20.From the reports of the culture from Thailand for the same species, the size of the hatchlings was 7.7 mm in DML and weighed 0.18 g while in the present study; the same species measured only 6 mm and weighed 0.0985 g. There is a marked difference for the same species from two different regions. The Paralarva of the same species from two different areas showed difference in the body weight and DML (7 mm DML and 0.9 g weight in average for the species from Andaman Sea) as stated by14. This is clear evidence that the size, hatching rate and survival depends on the geographical distribution of Sepia pharaonis and also the parent stock. Graphs 1 and 2 explains the difference between the culture results of present study and in Thailand. At 130 days culture period, the length of animals where to be almost same (84 mm for the present study and 84.1 mm for the Thai culture in average). The weight and length increase for the Thailand culture is higher when compared to the present culture. The Thai researchers had provided a mixture of live feed for the Paralarvae like post larvae of shrimps and mysids. The small size of the animals in the present study may be due to the difference in the nutritional value of the feed provided. Many workers have provided alternate diets to the mysids and brine shrimp like Gambusia sp. or other viviparous freshwater fishes18. All these experiments purely depend on the area they are being 846 INDIAN J MAR.SCI., VOL. 40, NO. 6, DECEMBER 2011 culture and the type of live feed available. The overall view of this experimental culture clearly indicates that a simple Closed Circulation System (CCS) is sufficient to raise the Pharaoh’s cuttlefish. Though mass rearing is possible, for a commercial basis, the escalating costs of live feed have to be taken uder consideration before venturing.
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