Rearing of  Mud Crab, Scylla tranquebarica Larvae with Different Stocking Densities

Mud crab (Scylla tranquebarica) is an important aquaculture species, especially in Southeast Asian Countries. However, the larval rearing of this species faces problems resulted in low survival caused not only by intensif canibalism but also by prolonged in larval rearing period. The stocking density during ealy life stages is proposed to influence the crablet production in the larvae rearing tanks. The objective of this research was to evaluate the effect of stocking densities on larval stage development and crablet production of mud crab, S. tranquebarica. Four different initial stocking densities of larvae were tested using 200 L fibre glass tank, namely: A). 30 ind,/L, B). 45 ind./L, C). 60 ind./L and D). 75 ind./L. Rotifer, Brachionus sp, and Artemia nauplii were fed to the larvae with additional commercial diet. Water exchanged in the rearing tank was performed since 7 days post hatching (dph) to 20 dph at a rate of 10 to 40%. Larvae from each experimental tank was sampled periodically (2 to 4 days interval) in order to calculate larvae population, larvae development index (LDI). Megalopa occurences index (MOI), and crablet production were also monitored. The result showed that the highest of LDI and MOI were obtained from treatment B and D which were significantly different (P<0.05) to the other treatments. Furthermore, the highest of crablet production was obtained from treatment D = 495.3+22.48 ind./tank, which was significantly higher (P<0.05) compared to treatment A (48.5+4.94 ind./tank), treatment B (167.5+10.61 ind./tank) and treatment C (218.33+10.41 ind./tank). Therefore, the stocking density of 75 ind./L is optimum for mud crab S. tranquebarica larvae and recommended to be applied for commercial larvae production in hatchery. Keyword: Production, crablet, stocking density, larvae, Scylla tranquebarica

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Optimisation of nursery rearing for megalopa of giant mud crab Scylla serrata (Forskal, 1775)

Indian Journal of Fisheries ◽

10.21077/ijf.2019.66.1.80293-06 ◽

2019 ◽

Vol 66 (1) ◽

Author(s):

Jose Antony ◽

C.P. Balasubramanian ◽

J. Balamurugan ◽

K.P. Sandeep ◽

I.F. Biju ◽

...

Keyword(s):

Body Weight ◽

Survival Rate ◽

Life Stage ◽

Survival Rates ◽

Stocking Density ◽

Scylla Serrata ◽

Larval Rearing ◽

Mud Crab ◽

Gracilaria Tenuistipitata ◽

Crab Larvae

Three nursery rearing trials were conducted to overcome the inconsistent survival of megalopa of the giant mud crab Scylla serrata (Forskal, 1775) during metamorphosis to crab instar. In the first trial, 3-4 days old megalopa (4.73 mg mean body weight) were stocked in hapas erected in outdoor brackishwater ponds and indoor fiberglass (FRP) tanks at densities of 500 nos. m-2 and 1 no. l-1 respectively and reared for 15 days using minced clam meat (Meretrix casta) as feed. Outdoor hapas were provided with seaweed, Gracilaria tenuistipitata as shelter. Mean survival rate of crab instar following three consecutive runs were significantly higher (p<0.05) for megalopa reared in outdoor hapas (57.7±2.7%) over indoor FRP tanks (24.1±2.2%). To ascertain the life stage that yields optimal survival on weaning from indoor hatchery to ponds, zoea 5 (Z5) and megalopa 1-day old (M1), 2-day old (M2), 3-day old (M3) and 4-day old (M4) were reared in hapas for15 days and fed on minced clam meat. Three day and 4-day old megalopa demonstrated significantly higher survival rates (p<0.05) of 62.3±3.08% and 69.6±2.35% respectively to crab instar stage at conclusion of the trial. Megalopa (3-4 days old, 5.05 mg mean body weight) were stocked to 100 l tanks (stocking density - 1 no. 4 l-1) and reared for a period of 8 days using different feeds viz., artemia biomass (T1), minced clam meat (T2), crab larvae (T3) and artemia nauplii (T4) in the third trial to evaluate various production parameters. Crab instar conversion rate (number of crab instars/number of megalopa stocked × 100) was significantly higher (p<0.0001) for megalopa fed using artemia biomass (T1) and minced clam meat (T2) at 74.66±5.81% and 72.00±2.30% respectively. Results of the present study indicate that, high density rearing (500 no. m-2) of megalopa (3-4 days old) in outdoor hapas provided with seaweed refuge for short periods (15 days) would yield higher survival rate to crab stage. Nursery rearing of megalopa in ponds reduces the hatchery phase in mud crab larval rearing and maximise production of crab instars.

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Malaysian Homestays: The Need for Standardized Regulation

Built Environment Journal ◽

10.24191/bej.v17i2.8997 ◽

2020 ◽

Vol 17 (2) ◽

pp. 63

Author(s):

ROHASLINDA BINTI RAMELE ◽

YAMAZAKI JUICHI ◽

MD NAJIB IBRAHIM ◽

LILIS SHEREENA SAFIEE

Keyword(s):

Rural Community ◽

Rural Tourism ◽

Asian Countries ◽

Government Organizations ◽

Rural Income ◽

Arts And Culture ◽

The Government ◽

Host Families ◽

Southeast Asian Countries ◽

Management Operation

This study aims to clarify regulations used among each type of registered and unregistered Malaysian homestays and to reveal issues arose regarding the implemented regulations. Selected homestays that are established by the government organizations and individuals were investigated to carry out the comparison on each homestay. Host families and persons in charge of the Ministry of Tourism, Arts and Culture (MOTAC), the Ministry of Agriculture (MOA), and the Ministry of Rural and Regional Development (MRRD) were also interviewed. Findings showed that there is only one guideline used for all types of homestays in Malaysia, which is the Malaysia Homestay Registration Guideline, established by MOTAC. MOTAC has also been selected as a leader of homestays in the Southeast Asian countries by the ASEAN Secretariat; therefore, the ASEAN Homestay Standard is also being referred. However, the implementation of this guideline and standard among other homestays unregistered with MOTAC (homestays established by MOA, MRRD, and individuals) is not compulsory, although encouraged, where they may receive equal benefits in term of facilities and promotion. Some issues arose due to the tax regulated by the local authorities, failure on homestays to be registered with MOTAC, and abandoned homestays. This study recommended that the Malaysia Homestay Registration Guideline to be standardized and regulated to all types of homestays, including individuals and unregistered homestays in Malaysia. This is important in order to reduce issues arose involving the homestay industry, providing safety and comfort to the tourists and, to help to develop rural income among host families and the rural community themselves.Keywords: Rural tourism, homestay, regulation, management, operation

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Factors Affecting Bank Risk-Taking: Evidence from Southeast Asian Countries

Journal of Economic Development ◽

10.24311/jed/2016.23.2.08 ◽

2016 ◽

Vol 23 (2) ◽

pp. 120-136

Author(s):

NGUYEN THANH LIEM ◽

TRAN HUNG SON ◽

HOANG TRUNG NGHIA

Keyword(s):

Risk Taking ◽

Southeast Asian ◽

Bank Risk ◽

Asian Countries ◽

Factors Affecting ◽

Southeast Asian Countries

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Transboundary Haze-Free for Southeast Asian Countries by 2020: A Delusional Vision?

International Journal of Psychosocial Rehabilitation ◽

10.37200/ijpr/v24i2/pr200494 ◽

2020 ◽

Vol 24 (02) ◽

pp. 1923-1929

Author(s):

Nurhidayatuloh ◽

Febrian ◽

Mada Apriandi ◽

Annalisa Y ◽

Helena Primadianti Sulistyaningrum ◽

...

Keyword(s):

Southeast Asian ◽

Asian Countries ◽

Southeast Asian Countries

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Exchange Rate Pass-Through into Import Prices In Major Southeast Asian Countries

SSRN Electronic Journal ◽

10.2139/ssrn.1295056 ◽

2005 ◽

Cited By ~ 1

Author(s):

Sahminan Sahminan

Keyword(s):

Exchange Rate ◽

Southeast Asian ◽

Asian Countries ◽

Import Prices ◽

Pass Through ◽

Exchange Rate Pass Through ◽

Southeast Asian Countries

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Current Progress and Future Directions in the Double Burden of Malnutrition Among Women in South and Southeast Asian Countries

SSRN Electronic Journal ◽

10.2139/ssrn.3215596 ◽

2018 ◽

Author(s):

Tuhin Biswas ◽

Nick Townsend ◽

R. J. Soares Magalhaes ◽

Md. Saimul Islam ◽

Md. Mehedi Hasan ◽

...

Keyword(s):

Southeast Asian ◽

Asian Countries ◽

Double Burden ◽

Future Directions ◽

Double Burden Of Malnutrition ◽

Southeast Asian Countries

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Quality of clinical practice guidelines for the management of hypertension in six Southeast Asian countries

Clinical and Experimental Hypertension ◽

10.1080/10641963.2021.1925683 ◽

2021 ◽

pp. 1-9

Author(s):

Chia Siang Kow ◽

Syed Shahzad Hasan ◽

Pei Se Wong ◽

Rohit Kumar Verma

Keyword(s):

Clinical Practice ◽

Clinical Practice Guidelines ◽

Practice Guidelines ◽

Southeast Asian ◽

Asian Countries ◽

Southeast Asian Countries

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How do Southeast Asian countries participate in the development of the Arctic

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/625/1/012009 ◽

2021 ◽

Vol 625 ◽

pp. 012009

Author(s):

E E Krasnozhenova ◽

S V Kulik ◽

T Chistalyova ◽

K Yu Eidemiller ◽

P L Karabushenko

Keyword(s):

Southeast Asian ◽

The Arctic ◽

Asian Countries ◽

Southeast Asian Countries

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Description of Echolocation Call Parameters for Urban Bats in Vietnam as a Step Towards a More Integrated Acoustic Monitoring of Urban Wildlife in Southeast Asia

Diversity ◽

10.3390/d13010018 ◽

2021 ◽

Vol 13 (1) ◽

pp. 18

Author(s):

Long Kim Pham ◽

Bang Van Tran ◽

Quy Tan Le ◽

Trung Thanh Nguyen ◽

Christian C. Voigt

Keyword(s):

Discriminant Function ◽

Discriminant Function Analysis ◽

Function Analysis ◽

Quantitative Description ◽

Southeast Asian ◽

Asian Countries ◽

Echolocation Call ◽

Echolocation Calls ◽

Pilot Work ◽

Southeast Asian Countries

This study is the first step towards more systematic monitoring of urban bat fauna in Vietnam and other Southeast Asian countries by collecting bat echolocation call parameters in Ho Chi Minh and Tra Vinh cities. We captured urban bats and then recorded echolocation calls after releasing in a tent. Additional bat’s echolocation calls from the free-flying bats were recorded at the site where we captured bat. We used the obtained echolocation call parameters for a discriminant function analysis to test the accuracy of classifying these species based on their echolocation call parameters. Data from this pilot work revealed a low level of diversity for the studied bat assemblages. Additionally, the discriminant function analysis successfully classified bats to four bat species with an accuracy of >87.4%. On average, species assignments were correct for all calls from Taphozous melanopogon (100% success rate), for 70% of calls from Pipistrellus javanicus, for 80.8% of calls from Myotis hasseltii and 67.3% of calls from Scotophilus kuhlii. Our study comprises the first quantitative description of echolocation call parameters for urban bats of Vietnam. The success in classifying urban bats based on their echolocation call parameters provides a promising baseline for monitoring the effect of urbanization on bat assemblages in Vietnam and potentially also other Southeast Asian countries.

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