First hatchery bred streaked spinefoot rabbitfish (Siganus javus) in Sabah, Malaysia

The present study aims to expand the market potential of the streaked spinefoot rabbitfish (Siganus javus) in Malaysia and provide consumers more choices of affordable protein source from aquaculture. Spawning hehavior of S.javus was recorded in a week after the new moon in October 2019 and January 2020. Spawning occurred between midnight and early morning, and the eggs hatched about 16 to 18 hours later. Throughout the incubation and larvae rearing period, water temperature was maintained at 30 to 31 °C. Water salinity, pH and DO were 31 to 33 ppt, 7.8 to 8, and 5 to 7 mg/l, respectively. Eggs diameter ranged from 0.550 to 0.603 mm. At 1 day after hatched (d AH), eyes of the larvae were formed but unpigmented and mouth structure was not developed. At 2 d AH, the pigmentation of eyes darkened, digestive tract formed, and anus and mouth opened. At 3 d AH, the lower jaw began to show movement, indicating that the ability of larvae to indulge in feeding. The buds of dorsal and ventral fins started to develop and elongate from 9 d AH and were covered with melanophores. At 25 d AH, the body of the larvae turned brownish and abdominal cavity was deeply pigmented, indicating the onset of metamorphosis. By the age of 30 d AH, the larvae completed development into juvenile stage. At 270 d AH, the juvenile reached maximum size of 21 cm in total length. This study was the first successful attempt at naturally spawning and hatchery rearing of S. javus into juvenile stage in the country. The development of a complete larval rearing protocol for S. javus could provide information of practical importance in hatchery breeding of other rabbitfish species.

The Use of Hematological and Histopathological Biomarkers to Assess the Health of Aquatic Ecosystems in Koh Sichang, Thailand

Koh Sichang area in Thailand is a sink for a wide variety of contaminants such as heavily polluted water from industry and oil spills. This situation may affect the health status of fish living in the area, but such information remains scarce. In this study, we evaluated the health status of java rabbitfish Siganus javus, an important marine fish in Koh Sichang, using hematological and histopathological biomarkers. All fish samples were collected from the Koh Sichang area during December 2017 and January 2018. Although the salinity, pH, and dissolved oxygen levels at sampling points were all within the normal range, abnormal nuclei were observed in erythrocytes (up to ~6% of all erythrocytes) and in some leucocytes (neutrophil, lymphocyte and monocyte). Visceral organs (gill, kidney and liver) were apparently normal in terms of gross morphology, but a wide variety of the histopathological alterations were found at the microscopic level: epithelial hyperplasia and aneurysm in gills; blood congestion and melanomacrophage centers (MMCs) in the liver; renal degeneration, granuloma and MMCs together with unidentified parasites in kidney. Calculation of semi-quantitative parameters [histological alteration index (HAI) and the average value of alteration (AVA)] demonstrated the highest frequency of histopathological alterations in kidney, suggesting that kidney is a sensitive organ. Overall, our observations suggest that S. javus in Koh Sichang is under the pathological state and warrants conservation efforts. Keywords: Erythrocytes, Fish Health, Hematology, Histopathology, Kidney

Short term culture of wild caught juvenile rabbit fishes (Siganus javus) in open sea cages at Palk Bay

Objectives: The main objective of the study was to collect and rear the unmarketable, small sized S.javus which is mostly rejected by the traditional fisherman. During fishing activities, under sized S.javus ranging in sizes from 25 to 40 kg (< 30-40 % of total catch/day) is being captured. Due to very low marketable value these small fishes (<250 g) get rejected. Therefore, we utilized this as an economically viable option for utilization as seeds for rearing until they reach the necessary marketable size. Methods: Undersized juveniles (12-16 cm, 40 -55 g) were collected from nearby Olaikuda village,Rameshwaram using traditional traps made using bamboo and odai tree bark (Acacia planifrons). The collected juveniles were stocked in sea cages and fed with locally formulated plant based feed containing 28-32 % crude protein. Findings: Harvesting was successfully done after 140 days with 90 % survival. The average growth rate achieved was 2.5 g /day with FCR of 2.01. This resulted in an average harvest size of 400 g/fish from its initial stoking size of 50 g with an attracted market value of Rs. 150/kg. Novelty: Till date, no attempts were made to commercialize such harvesting techniques for the species Siganus javus in pilot scale in India (Except James, 1984). Keywords: Rabbit fish; Siganus javus; sea cage culture; rabbit fish culture; Siganidae

Fish Assemblages in Iraqi Marine Waters, North West The Arabian Gulf

The composition of fish assemblages in Iraqi marine water was assessed. 91 species belonging to 71 genes and 47 families of Osteichthyes and 13 species of Conderchthyes were collected during the study period from January to December 2018, using trawl net fishing. Three stations were selected, where two new species (Siganus javus and Gobiopsis sp.) and reclassification of Torpedo panthera where identified and two species of freshwater fish (Oreochromis niloticus and Oreochromis aureus) were first recorded in marine waters. The highest numbers of species were 32 and 42 for the first and second stations, respectively, recorded in October , while 55 species were recorded in the third station during August. Leiognathus bindus was the dominant species in the first and second stations, while Ilisha compressa dominated the third station. Carangidae and Sciaenidae were the dominant families in number of species (7 and 5, respectively), whereas 4 species were recorded for Clupeidae, Sparidae, Mugilidae and Gobidiae.

Heavy metals content (Hg, Cd, Pb, and Cu) in streaked spinefoot Siganus javus (Linnaeus, 1766) in Bojonegara Waters, Banten Bay, Indonesia

Anthropogenic activities contribute to heavy metals so that their concentration in the waters increases and causes accumulation, especially in streaked spinefoot. This study aims to estimate the level accumulation of (Hg, Cd, Pb, and Cu) heavy metals contained in streaked spinefoot (Siganus javus) meat in Bojonegara waters, Banten Bay, Indonesia. A sampling of 30 to 50 grams of fish meat is carried out every month from August to October 2020 and heavy metals analysis in streaked spinefoot meat was carried out in February 2021 using atomic absorption spectrophotometry (AAS). The (Hg, Cd, and Pb) heavy metals contained in the streaked spinefoot meat were undetected by the AAS, while the content of heavy metal Cu on small fish is 0.348 to 1.530 mg kg-1, and large fish is less than 0.015 mg kg-1 to 5.390 mg kg-1. Bioaccumulation Cu metal in small and large streaked spinefoot included low to high accumulation, while it was low for other types of metal. The safe limit for consumption of streaked spinefoot meat for adults (50 kg) is 32.468 kg of meat/week, while for children (15 kg), it is 9.740 kg of meat/week.

First Record of Streaked Rabbitfish Siganus Javus (L., 1766) from the Iraqi Marine Waters, with Re Description of White-Spotted Rabbitfish Siganus Canaliculatus (Park, 1797)

Two Siganid fishes were described in the current study, the first one is Siganus javus (Linnaeus, 1766) as a new record and the other Siganus canaliculatus (Park, 1797), which was collected from the Iraqi marine waters. The samples were collected during December 2018. Streaked rabbitfish S. javus is diagnosed by a deep body, 54.01% in standard length, depth of caudal peduncle, 7.27%, total gill rakers 19 and silvery blue undulating lines on mid and lower sides of the body. Whereas the body depth of White-spotted rabbitfish S. canaliculatus was 39.08-42.66%, Caudal peduncle depth ranged from 5.21 to 5.66%, total gill rakers ranged from 22 to 24 and it is distinguished by a numerous pearly blue to whitish spots on the nape and trunk.

PERBANDINGAN HASIL TANGKAPAN BUBU PADA JENIS TERUMBU BUATAN BAN DAN BAMBU DI PERAIRAN DESA TOISAPU KECAMATAN BAGUALA AMBON

Information about material kinds of artificial reef which effective for marine organism habitat is rare. Based on this fenomena, It is important to conduct a study about bamboo and tire artificial reef. The objective of this study is to find out a catch comparison and species compotition of pot catch on bamboo and tire artificial reef. Alternatif a widely used materials are bamboo and tire with consideration easy to obtain and economis. The result of this study show that the total catch during the study was 170 fishes from 8 species dominated by Siganus javus, Seranidae sp and Carangidae sp. The total catch of the Tire artificial reef was 87 fishes including 48,19 % Siganus sp, 23,53% Seranidae sp and 10,06 % Lethrinidae sp where as Bamboo artificial reef was 83 fishes including 33,34 % Siganus sps,26,3% Seranidae sp and 14,26 % Carangidae sp . The result showed that catch of bamboo artificial reef was significantly difference from the catch of tire artificial reef where the catch of tire artificial reef was higher than that catch of bamboo artificial reef.

POLIKLULTUR IKAN KERAPU LUMPUR (Epinebhelus suillus) DAN BERONANG (Siganus javus) YANG DIBERI PAKAN BERBEDA DALAM HAMPANG DI TAMBAK

Telah dilaklkan penelitian pemberian jenis pakan berbeda dalam polikultur ikan kerapulumpur (E,suillus) dan beronang (S.javus) untuk mengetahui pengaruh jenis pakan terhadap pertumbuhan dan kelangsungan hidupnya. Empat jenis perlakuan yang telah dilakukan yaitu pakan komersial atau pelet untuk ikan bandeng (A), ikan mujair (B), campuran pelet dengan ikan mujair (C) dan tanpa pakan (D).