A PRELIMINARY STUDY ON CULTURE OF MANGROVE RED SNAPPER, Lutjanus argentimaculatus (Forsskål, 1775)

Vutthichai Oniam^*, Wasana Arkronrat, Rungtiwa konsantad

Klongwan Fisheries Research Station, Faculty of Fisheries, Kasetsart University, Prachuap Khiri Khan 77000, Thailand

^*Corresponding author:  ffisvco@ku.ac.th

Mangrove red snapper, Lutjanus argentimaculatus is one of most popular fish in the Southeast Asia region, where production is primarily done in Hong Kong, Malaysia, Singapore, Taiwan and Thailand. Meanwhile, the culture of this fish depends on source of seed or juvenile fishes from natural water, and studies on broodstock production under pond conditions are very limited. To cope with this problem, restocking into existing fisheries and developing the aquaculture of L. argentimaculatus are promising solutions. The objectives of this study were to study of water salinities (0, 15 and 30 ppt) on juveniles fish growth and survival, and to summarize fish reared in earthen ponds and the main cause of mortality in fish at during 12 months of the culture period. The results showed that the survival rate and specific growth rate (SGR) of fish reared in water salinity of 0, 15 and 30 ppt were not significantly different (P>0.05). In addition, fish reared in the earthen ponds at 12 months found that mean total length, body weight, survival rate, SGR of body weight and FCR were 39.7 cm, 1,072.3 g, 91.2 %, 0.53 % per day, and 8.2, respectively. Main cause of fish mortality found that occurs virus infection (viral nervous necrosis, VNN) at about 4-5 months after rearing. The rate of fish mortality was between 3.2-8.7 %. Knowledge gained from this study is useful for production and culture development of L. argentimaculatus in the future.

Keywords: Lutjanus argentimaculatus, Mangrove red snapper, Culture

A STUDY ON THE EFFECT OF WATER PARAMETERS ON THE SURVIVAL AND GROWTH RATE OF SEA BASS, LATES CALCARIFER (BLOCH, 1790)

Jue Ko Ko Thet*

Master student, Marine Science Department, Pathein University, Myanmar

*Corresponding author: juekokothet@gmail.com

An investigation on the effects of water quality on the growth and survival rates of sea bass (Lates calcarifer) culture was conducted at the Yuzana Company’s sea bass grow-out farms which is geographically located at Latitude 16°50'50.96"N and Longitude 94°26'29.09"E, Southern Rakhine Coast, Myanmar. Four 7,225 m2 (85m×85m) grow-out cultured earthen ponds were used with the stocking density of 2 pcs/ m2 in each pond and the duration of the research was six months.  The formulated foods manufactured by Htoo Thit and Aller Aqua Co.Ltd were used to feed the cultured fishes and given regular aeration by paddle wheels. The important water parameters, temperature, pH, dissolve oxygen, salinity, alkalinity, nitrite and ammonia were regularly measured both in situ and in laboratory. The growth and survival rates of the cultured sea bass were regularly determined and FCR ratio was also noted. Pond H-6 and H-7 were obtained FCR 1.7 and 1.6 (used Htoo Thit). Pond H-4 and H-5 were obtained FCR 1.8 and 2 (used Aller Aqua). Pond H-6 and H-7 were obtained 32,213.2 kg and 33,981.3 kg. Pond H-4 and H-5 were obtained 30,682.6 kg and 30,484.1 kg. Pond H-6 and H-7 (used Htoo Thit) obtained survival rate 99% and 96%. Pond H-4 and H-5 (used Aller Aqua) obtained survival rate 98 % and 94%. Results showed that the temperature and dissolve oxygen, nitrite and ammonia effect significantly on the growth and survival rates of the cultured fishes.

Keywords: FCR ratio, grow-out culture, Lates calcarifer, sea bass, water quality

ECOLOGICAL CARRYING CAPACITY OF SUSTAINABLE INTENSIVE SHRIMP FARMING IN SANDY COASTAL AREA

Susilo B. Priyono¹*, Rustadi¹, Triyanto¹, Sudarmadji²

¹ Department of Fisheries, Faculty of Agriculture, Gadjah Mada University, Jl Flora, Bulaksumur, Yogyakarta, Indonesia.

² Department of Environmental Geography, Faculty of Geography, Gadjah Mada University, Sekip Utara, Bulaksumur, Yogyakarta, Indonesia.

*Corresponding Author: sbpriyono@ugm.ac.id

Ecological carrying capacity (EEC) is the stocking or farm density which causes unacceptable ecological impacts. This study aims to estimate the ECC of sustainable intensive shrimp farming in sandy coastal area for obtaining a maximum pond area and producing shrimp without negative impact to the aquatic environment. This research was conducted in a commercial scale of intensive shrimp pond located in Bantul Regency, Indonesia. Estimation of ECC is based on modeling of Total Nitrogen (TN) loading originated from shrimp feed which affects nutrient loading in the aquatic environmental. The average of shrimp pond is 3,088 m² with stocking density of 118 post-larva/m². After rearing for 13 weeks (90 days), shrimp production was obtained as much as 4,626 kg or 14.98 tons/ha, with survival rate of 84.75% and a feed conversion ratio (FCR) of 1.41. The results showed that nutrient retention of TN in the shrimp body is 45.03% and the rest of the TN is discharged into the aquatic environment. The total load of TN waste from feed is 179.14 kg, which 53.74 kg of them is effluent. Based on the nutrient loading and the volume of waters receiving waste, the EEC of the area for development of intensive shrimp farming is 382 tons or equivalent to pond area of 83 ha.

Keywords: ecological carrying capacity, sustainable, total nitrogen, whiteleg shrimp

EFFECTS OF MATERNAL EXPERIENCE IN SALINITY CONDITIONS ON OFFSPRING PERFORMANCE OF  BIGHEAD CATFISH (Clarias macrocephalus)

Joachim Raymond Temu^1*, Ngoc-Tran Thi Nguyen², Thuy-Yen Duong²

¹International Master program in Aquaculture, Can Tho University, Can Tho City, Viet Nam

²College of Aquaculture and Fisheries, Can Tho University, Can Tho City, Viet Nam

^*Corresponding author: temujoachim@yahoo.com 

Maternal experiences were reported to have significant attributes to offspring’s ability to cope with environmental extremes. This study investigated the effects of females cultured for one year in three salinities (0, 4, and 8ppt) on offspring performance, at larvae and juvenile stages, under different rearing salinities of bighead catfish. Three female groups were artificially fertilized with the same freshwater source of males. In the larval experiment, 550 larvae were randomly stocked in 50L tanks (three replicates) and reared at 0, 2 and 4 ppt for 20 days. Two-way ANOVA analyses showed that there were no interactions between maternal salinity and larval rearing salinity on the offspring’s growth and survival rate (SR). Growth were not significantly different among three levels of each factor (P>0.05). However, SR increased with the increase of maternal salinity and rearing salinity (P<0.05). In the juvenile stage, 110 fingerlings pooled by treatments from the first experiment were stocked in 50L tanks with three replicates and reared at 0, 3 and 6 ppt. After 40 days, growth and SR were affected by both maternal salinity and rearing salinity (P<0.05) but not their interactions (P>0.05). The growth of juveniles from female groups 0 ppt and 4 ppt were similar (1.57±0.30g and 1.40±0.23g, respectively) and significantly higher than that of juveniles from 8 ppt-females (1.24±0.27g). Fish reared in 0 ppt grew faster than those in 3 and 6 ppt. Moreover, juveniles’ SR from maternal salinity of 0 ppt (46.0%) was significantly higher compared to 4 ppt (40.9%) and 8 ppt (42.4%). Rearing salinity of 3 and 0 ppt also resulted in significantly higher SR (46.5% and 45.9%, respectively) than that of fish reared at 6 ppt (37.5%). In sum, effects of maternal cultured salinity and rearing salinity on offspring’s growth and survival were not consistent at larval and juvenile stages.

Keywords: Catfish, Cultured salinities, Growth performance, Early stages, Maternal effects

GROWTH PERFORMANCE OF MUD CRAB JUVENILES Scylla olivacea AND S. tranquebarica IN THE BRACKISHWATER POND AND THEIR MOLTING INCREMENT FROM IMMATURE TO MATURE STAGES IN CAPTIVITY

Muhammad N. Syafaat^1,2, Khor Waiho¹, Gunarto² and Mhd Ikhwanuddin^1*

¹Institute of Tropical Aquaculture (AKUATROP), Universiti Malaysia Terengganu, Kuala Nerus, Terengganu, Malaysia.

²National Research and Innovation Agency (BRIN), Jakarta, Indonesia

*Corresponding author: ikhwanuddin@umt.edu.my

Scylla olivacea (SO) and S. tranquebarica (ST) are often found living in the same habitat around river estuaries, so both are good candidate species to be cultivated in brackishwater ponds. The results of thepresent study are expected to be the basis for selecting species that are more suitable for rearing in ponds based on their growth performance criteria. This study tried to compare the growth performance of SO and ST crablet (carapace width ±1cm) in the earthen pond and their female molting increment from immature (carapace width of SO and ST namely 94.53mm±5.98 and 100.19mm±5.16 respectively) to the mature stage. The results showed ST had a better growth rate than SO based on the results of growth sampling in the first, second, and third months (P<0.05). The carapace width and average weight obtained in the third month for SO and ST were 82.82mm/103.46g and 90.57mm/131.03g respectively. The averages of the molting increment from immature to mature stages of SO and ST were 15.95% ±.36 and 14.40% ±SD3.11 respectively, and the results were similar (P>0.05). The results can be used in choosing a candidate species of mud crab that has a better growth performance in the brackishwater pond, namely S. tranquebarica. The results also show that the molting increment of both species in the immature phase to the mature phase is the same, although ST can reach a larger size than SO in the wild.

Keywords: Mud crab juvenile, Aquaculture, Brackishwater pond, Molting increment

Micropropagation of eucheumatoids using brown seaweed liquid extracts from Ascophyllum nodosum and Laminaria digitata

Iris Ann Borlongan^1*, Hazel Coleen Gaya¹, Antoniette Lorain Dimaano¹, Franck Hennequart², Alan Critchley³, Anicia Hurtado⁴

¹Institute of Aquaculture, College of Fisheries and Ocean Sciences, University of the Philippines Visayas, 5023 Miagao, Iloilo, Philippines

²Algaia R&D Center  91 rue, Edouard Branly 5000 Laint-Lo France

³Verschuren Centre for Sustainability in Energy and Environment, Cape Breton, Canada

⁴Integrated Services for the Development of Aquaculture and Fisheries (ISDA) Inc., McArthur Highway Tabuc Suba, Jaro, 5000 Iloilo, Philippines

*Corresponding author: igborlongan@up.edu.ph

Eucheuma denticulatum and Kappaphycus alvarezii are two commercially important, cultivated  carrageenophytes in Southeast Asia. Large-scale farming of these seaweeds through repeated vegetative propagation and virtual monocropping has resulted in various phyconomic issues. The efficacy of commercial liquid extracts from the brown seaweeds Ascophyllum nodosum (ANE) and Laminaria digitata (LDE) on the direct formation of axes and survival of  these two eucheumatoids were examined using tissue culture techniques. Seaweed apical sections (3–5 mm long) were cultured for 45 days at different concentrations of ANE and LDE (i.e., 0.01, 0.1, 1.0, 3.0, 5.0 mL 2L^-1), and control (UV-filtered seawater). Results revealed that the effects of the two seaweed liquid extracts were different between species; LDE provided better overall performance to E. denticulatum, while ANE to K. alvarezii in tissue culture. The present study recommends the use of 0.1 mL LDE 2L^-1 for optimum results for the tissue culture of E. denticulatum, given the high percent survival (95.3 ± 0.9%), percent formation of direct axes (95.3 ± 0.9%), and their longest length (10.0 ± 0.3 mm) at the end of a typical 45-day culture period, as well as the highest percentage formation of axes at day 14 (88.0 ± 4.9%). Either 0.01 or 0.1 mL ANE 2L^-1 is recommended in tissue culture of K. alvarezii. Given the effects on survival, direct axes formation and length were different, interpretations should be made with caution after much consideration as to which growth indicators should be given priority. Additional experiments for K. alvarezii are necessary to ensure reproducibility of results in order to confirm the optimum concentration of ANE or LDE that can be applied for mass production of plantlets for out planting purposes. Some of these additional data will be discussed in the presentation.

Keywords: Kappaphycus alvarezii, Eucheuma denticulatum, Ascophyllum nodosum, Laminaria digitata, micropropagation, biostimulant